Review and Experimental Long Range Forecast for SW England. October 2018.

Published 20 October 2018

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1. Influences.

Changes in sea temperature.

181018sst

The sea temperature around the UK remains well above normal in the south but has shown some cooling in the north. The northern North Atlantic remains below normal as is the Great Lakes area which is a little surprising given the milder than average temperatures in the area over the later month or so. Recent tropical storms do not seem to have material depressed sea temperatures to the S and E of the USA and transition towards El Nino can be seen in the Pacific.

tna_anom_20181001

Met Office plot of tropical North Atlantic sea temperature (above right) seems to have picked out a colder area but in the Pacific there is broad inter-model agreement for an El Nino (Enso 3.4 area) and possibly a longer lasting event than previously forecast.

The dominant IRI statistical predictor for UK rainfall based on the Pacific sea temperature anomalies for the winter season is shown below. Probabilities are for “near normal” precipitation,

elninonormal

The North Atlantic Oscillation index (shown by a 500hPa index in the image below) had been mostly in a positive phase but is forecast to turn sharply negative in a week or so reflecting the cold northerly plunge into UK/Central Europe after the 26th of October rather than increased Atlantic mobility although this may occur in the far North of the Atlantic.

NOA

For background information see the Met Office NAO information.

Recent Climatology

Temperatures during September in SW England were near average following an unusually warm summer. Rainfall in September was near or a little below average and followed a drier than average summer.

HSRA0918

Although there has been some significant rainfall recently, after the preceding drier months soil moisture content remains below normal in the south of UK. The present dry spell looks like reducing the water content further; as shown by the GFS analysis and forecast below.

sm1018

Rover flows in September reflect the longer term drier period being near or below normal for September and more especially the June to September period. Ground water in the east of the region is was near normal. The full Hydrological Summary for September can be viewed here – September 2018 summary PDF 

river

The reservoir levels in the SW of England (14th October) show 51% storage which is a further decrease since last month although recent heavier rain has caused a slight uptick in levels.

res

The experimental product from the Global Flood Awareness System based on early October ECMWF seasonal forecast for October to January. It should be noted that severe flooding due to tropical storms has not been captured this year and it is likely that the system is better suited to persistent broad scale rain types. This month the output does not indicate a preference for below or above normal area rainfall but has local river flow shown as above (blue) or below (orange) normal.

glofas

Atmosphere predictions.

A:  Stratosphere and Upper Troposphere

The N Pole stratosphere is cooling in line with normal variations and the polar vortex has formed as shown by the 30hPa analysis on the 19th October 2018.

30hpa

CFS2 200hPa data (as supplied to NNME data set October 2018) for the December to February 2019 period continues to suggest above normal heights across the UK. for both December and January there are signs of enhanced jets suggesting stormy spells at least for the north of the UK.

z200DJF1018

Winter monthly mean 200hPa height forecast and anomaly

For Spring above normal heights predominate but with a rather more cyclonic pattern for parts of April hinted at in the anomalies.

z200MAM1018

Spring monthly mean 200hPa height forecast and anomaly

B: Lower Troposphere:

Graphics for November available via web link seasonal latest.

Comparing CFS2 NMME and ECMWF model output for the winter months (December January and February). Oranges/red are above “model normal” blues are below.

CFS2e3djf102018

CFS2 E3 10 day mean of output. Top temp anomaly Lower precipitation rate anomaly.

nmmedjf102018

NMME.  Top temperature anomaly Lower precipitation rate indication.

ECDJF102018

There is some agreement for temperature anomalies to become more positive during the winter season but rain rate anomalies are unclear and by February EC has the opposite signal to that of  NMME.

NMME data for Spring (March to May 2019) perhaps indicate a colder start to spring in the SW and a milder end with increased precipitation in April compared to average. There is perhaps an increase snow risk in the southwest in March than average following a decrease in snow in Winter.

nmmemam102018

Full size graphics and a text review of other seasonal models can be viewed at www.weather-info.co.uk/wxsvc/seaslatest.html

2. Forecast.

November 2018

Probably milder and wetter than average. See month ahead forecast  here

Winter 2018/9  (December January and February).

Main consensus is for above average temperatures for the season but perhaps starting off with near normal values in December then trending milder than average later in the winter.

Rainfall likely to be above normal for the season especially in the west with some parts of the east of SW England having near normal precipitation.

Below average snowfall is likely with the highest risk of snow possibly late in the winter and chiefly over the moors.

Winter Climate: 1981-2010 average temperature values for lowland areas 7°C in the West and 5°C in the East. Rainfall; Dec and Jan typically wetter than February. 1981-2010 Autumn average 300-400 mm lowlands but 200-300 mm areas to E of Dartmoor. Snow climatology less than 5 days lying snow over lowland areas 5 to 10 hills, say hills around 200 metre elevation – one in three years have no lying snow.

Spring 2019  (March April May) based on less data.

Possibly a colder than average March then recovering to milder than average temperatures for the season.

March may be drier than average but with increased snow risk. April and May probably wetter than average especially April.

Spring climate: 1981-2010 average mean temperature 9 or 10°C but a few degrees cooler over the moors. Roughly Mar 7 or 8°C Apr 8 or 9°C  May 11 or 12°C. Average 1981 to 2010 rain 200 to 300mm lowest values in E Devon and over parts of Somerset.

Summer 2019  (June July August) based on very limted data.

Another warmer than average summer according to 2 out of 3 available models with above normal rain although early summer may be drier than average.

Summer climate: 1981 to 2010 average daily mean temperature 14 or 15°C in many areas to 16 or 17°C in main urban areas also locally east of the moors and more widely in Somerset. Maximum temperatures average 19 to over 21°C in similar areas. July often warmer than August. Average 1981 to 2010 rain 300mm over the moors, typically 200 to 250mm in many coastal and eastern areas. June often drier than July and July drier than August.

3. Caution.

Experimental Long Range Forecasts do not have a good success rate. The data used for the above forecast summary can be seen at  here.

The attempt at a Regional Forecast for SW England aims to test whether such a forecast of temperature and rainfall variation from average can be made using numerical model data available on the internet. The forecast should not be used for any other purpose. A brief verification summary for the UK and Eire is routinely published at http://www.weather-info.co.uk/wxsvc/Verification.html or Click here for the Teignmouth and Dawlish summary

4. References.

SST anomaly NOAA Remote Sens. 2014, 6(11), 11579-11606; doi:10.3390/rs61111579

IRI statistics: Mason, S.J. and L. Goddard, 2001: Probabilistic precipitation anomalies associated with ENSO. Bull. Amer. Meteor. Soc., 82, 619-638.

UK climate details see: http://www.metoffice.gov.uk/public/weather/climate/

NMME information:   http://journals.ametsoc.org/doi/abs/10.1175/BAMS-D-12-00050.1

CFS2  info

GLOFAS Acknowledgement: Data were provided by the Global Flood Awareness System – GloFAS (http://www.globalfloods.eu/) of the European Commission Joint Research Centre and the European Centre for Medium-Range Weather Forecasts.
Reference: Alfieri, L., Burek, P., Dutra, E., Krzeminski, B., Muraro, D., Thielen, J., and Pappenberger, F.: GloFAS – global ensemble streamflow forecasting and flood early warning, Hydrol. Earth Syst. Sci., 17, 1161-1175, doi:10.5194/hess-17-1161-2013, 2013.

‘Copernicus Products’  as listed in the C3S or CAMS Service Product Specification or any other items available through an ECMWF Copernicus  http://climate.copernicus.eu

ECMWF seasonal monthly data from weather.us

Stratospheric Diagnostics from Free University Berlin

Climate data from The Met Office UK and NCEP USA.

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Review and Experimental Long Range Forecast for SW England. Sept 2018.

Published 17 September 2018

GDPR statement: Please note that the author of this blog does not set cookies but the host “wordpress.com” sets multiple cookies which are outside of the authors control. You can view their cookie policy here. 

1. Influences.

Changes in sea temperature.

130918sstAnom

The sea temperature around the UK remains well above normal. The colder area in the northern North Atlantic has reduced in extent slightly but recent tropical storms probably resulted in the cooler than normal SST extending from off the coast of Africa towards the USA. Despite this recent cooling the forecast, shown below, remains for a slightly warmer than normal tropical Atlantic but any future storms may need to track a little further south than Florence to benefit from warmer than normal sea temperatures.

tropsst

Cooling can also be seen in the Pacific following recent storms affecting Japan and the Philippines. Progress towards an El Nino state in the Pacific seems to have stalled a little, much like last months ECMWF plume suggested. For the ENSO area 3.4 the ECMWF and UKMO forecast (shown below) is just a little cooler than the CFS2 forecast (above).

tropsst1

The IRI statistical predictor for UK rainfall based on the Pacific sea temperature anomalies is unlikely to be of use until the El Nino has established for the winter. The graphic below shows the probs for normal precipitation this winter during an El Nino.

elninonormal

The North Atlantic Oscillation index (shown by a 500hPa index in the image below) had been mostly in a positive phase but is forecast to turn neutral or negative in the next few weeks suggesting some increased in Atlantic mobility.

naosep2018

For background information see the Met Office NAO information.

Recent Climatology

Temperatures during August in SW England were near or above average with the summer generally above normal making 2018 one of the warmest summers on record. Rainfall in August was more variable and closer to average but for the summer as a whole it was much drier than average as can be seen in the graphics below.

clim09

Following the dry weather water content in the top of the soil remains low is likely to further reduce in most areas. See GFS analysis and forecast below.

09smchange

Rover flows in August reflect the longer term drier period. Ground water in the east of the region is near normal, see the full Hydrological Summary for  August for the full details – August 2018 summary PDF 

08riverflows

The reservoir levels in the SW of England (9th Septemer) show 55% storage which is a further decrease since last month.

resevoir

The experimental product from the Global Flood Awareness System based on ECMWF seasonal forecast for September and August data is shown below. It should be noted that recent severe flooding in North Carolina and also in China due to tropical storms was not captured by this system. It is likely that the system is better suited to persistent broad scale rain types rather than one off events as the data is typically means over a period.

SEP2018glofas

Atmosphere predictions.

A:  Stratosphere and Upper Troposphere

The N Pole stratosphere is cooling more or less along the mean although there have been some colder than normal occasions and the polar vortex is forming as shown by the 30hPa analysis on the 16th.

ecmwf30a12

CFS2 200hPa data (as supplied to NNME data set September 2018) for the December to February 2019 period continues to suggest above normal heights across the UK. By January enhanced jet strength across the Atlantic is indicated suggesting greater storminess for the UK. By February this is perhaps confined to the far NW.

z200DJF0918

CFS2 monthly mean 200hPa contour height (upper row) and anomaly (lower row) 

B: Lower Troposphere:

Graphics for October and November available via web link seasonal latest.

Comparing CFS2 NMME and ECMWF model output for the winter months (December January and February).

E3DJF0918

CFS2 E3 10 day mean of models. Top row temperature anomaly, lower row rain rate anomaly.

NMMEDJF0918

NMME data. Top row temperature anomaly, lower row rain rate indication.

ECDJF092018

ECMWF Top row temperature anomaly. Lower row rain anomaly (blue is below normal)

 

Most models forecast above normal temperatures for the remainder of Autumn and also for winter. ECMWF, however,  suggests below normal temperatures in January 2019 supported only by JAMSTEC although a few also have near normal values rather than milder temperatures.

Rainfall is a more varied picture in the models but some agreement that parts of the UK, probably the south may have above normal rain at least for December and January.

Full size graphics and a text review of other seasonal models can be viewed at www.weather-info.co.uk/wxsvc/seaslatest.html

2. Forecast.

Remainder of Autumn 2018  (October November). 

Milder than average but perhaps for November much milder than normal.

Rainfall starting below normal in October but trending wetter than average for November but uncertainty as to when the change to wetter types will start.

Autumn climate: 1981 to 2010 average mean temperature 11 or 12°C but nearer 10°C in rural areas. Maximum temperatures average 14 to 16°C. November normally colder than October which is colder than September. Average 1981 to 2010 rain 300 to 400mm, 600 to 800mm over the moors but east of the moors and in lowland Somerset more like 200 to 300mm. September often drier than October or November.

Winter 2018/9  (December January and February).

Almost no indication for a colder than normal winter. Main theme is above or well above average temperatures, with just a hint of the temperature only slightly milder than average in wither January or February, the latter being the most likely month.

Rainfall likely to be above normal for the season. There are some indications for drier periods but not much agreement between models in location or timing. May lead to some eastern parts being near average rainfall rather than above and February may be drier than average.

Below average snowfall with the highest risk of snow possibly in January and chiefly over the moors.

Winter Climate: 1981-2010 average temperature values for lowland areas 7°C in the West and 5°C in the East. Rainfall; Dec and Jan typically wetter than February. 1981-2010 Autumn average 300-400 mm lowlands but 200-300 mm areas to E of Dartmoor. Snow climatology less than 5 days lying snow over lowland areas 5 to 10 hills, say hills around 200 metre elevation – one in three years have no lying snow.

Spring 2019  (March April May) based on limited data.

Continuing with milder than average temperatures though some months may be near average. Rainfall below normal at least for one month and probably near or below normal for the season.

Spring climate: 1981-2010 average mean temperature 9 or 10°C but a few degrees cooler over the moors. Roughly Mar 7 or 8°C Apr 8 or 9°C  May 11 or 12°C. Average 1981 to 2010 rain 200 to 300mm lowest values in E Devon and over parts of Somerset.

3. Caution.

Experimental Long Range Forecasts do not have a good success rate. The data used for the above forecast summary can be seen at  here.

The attempt at a Regional Forecast for SW England aims to test whether such a forecast of temperature and rainfall variation from average can be made using numerical model data available on the internet. The forecast should not be used for any other purpose. A brief verification summary for the UK and Eire is routinely published at http://www.weather-info.co.uk/wxsvc/Verification.html or Click here for the Teignmouth and Dawlish summary

4. References.

SST anomaly NOAA Remote Sens. 2014, 6(11), 11579-11606; doi:10.3390/rs61111579

IRI statistics: Mason, S.J. and L. Goddard, 2001: Probabilistic precipitation anomalies associated with ENSO. Bull. Amer. Meteor. Soc., 82, 619-638.

UK climate details see: http://www.metoffice.gov.uk/public/weather/climate/

NMME information:   http://journals.ametsoc.org/doi/abs/10.1175/BAMS-D-12-00050.1

CFS2  info

GLOFAS Acknowledgement: Data were provided by the Global Flood Awareness System – GloFAS (http://www.globalfloods.eu/) of the European Commission Joint Research Centre and the European Centre for Medium-Range Weather Forecasts.
Reference: Alfieri, L., Burek, P., Dutra, E., Krzeminski, B., Muraro, D., Thielen, J., and Pappenberger, F.: GloFAS – global ensemble streamflow forecasting and flood early warning, Hydrol. Earth Syst. Sci., 17, 1161-1175, doi:10.5194/hess-17-1161-2013, 2013.

‘Copernicus Products’  as listed in the C3S or CAMS Service Product Specification or any other items available through an ECMWF Copernicus  http://climate.copernicus.eu

ECMWF seasonal monthly data from weather.us

Stratospheric Diagnostics from Free University Berlin

Climate data from The Met Office UK and NCEP USA.

 

Experimental Long Range Forecast for SW England. March 2018 issue.

Published 20 March 2018. (correction July rainfall 02April)

GDPR statement: Please note that the author of this blog does not set cookies but the host “wordpress.com” sets multiple cookies which are outside of the authors control. You can view their cookie policy here. 

1. Influences.

Changes in sea temperature.

anomnight.3.15.2018

Sea Temperatures have cooled relative to average around the UK and western Europe due to the cold easterly types early and middle March know as the “Beast from the East” and “mini Breast from the East”, resulting partially from the sudden stratospheric warming during February. This is likely to have impact on temperatures across the UK during the remainder of  March and at least for the start of April. Elsewhere the anomalies are not very different to last month with North Atlantic anomalies still above average. Sea temperatures in the tropical Atlantic area have continued to cool and are forecast remain slightly below average for the next few months as shown by the UK Met Office plot below.

tna_anom_20180301

The La Nina in the Pacific is well established (as shown by the sea temperature anomaly chart at the top of the page) with a large area of below normal sea temperatures in the eastern Pacific near the equator. The CFS2 forecast for the La Nina suggests it may continue as a weak feature through summer and autumn, as shown by the graphic below (top right panel). This is not supported by either UKMO or ECMWF forecast which trends to neutral or El Nino conditions. A consensus appears to be more towards the Neutral/El Nino than staying with a weak La Nina.

SST1

A consequence is that the IRI relationship between ENSO and UK rainfall is likely to be unreliable and is not reproduced in this document.

The North Atlantic Oscillation index (shown by a 500hPa index in the image below) went into a negative phase, as suggested by some models, late in February but may well return to a positive phase over the next few weeks.

SST2

For more information see Met Office NAO information.

Changes in the upper atmosphere.

A sudden stratospheric warming (SSW) did develop from about the 12th February leading to a reversal in the stratospheric winds over the UK area and a weakening of the jet stream across the Atlantic. Tokyo issued a STRATALERT EXISTS message and a final END message on the 16th March. ECMWF 30hPa chart for 12Z 11th February and 12Z on the 18th March 2018 shows the effect of the warming on the stratospheric polar vortex which is well on the way to “summer” mode.

SSW

Analysis and Numerical (model) output.

A: Recent Climatology.

recent climat

February was colder and drier than normal but for the winter as a whole temperatures in the south of UK were near average and for the SW rainfall was not far from normal though slightly wetter in the west and drier in parts of the SE of the region. March so far has continued with the cold theme with temperature anomalies over 1 degree below the average. Rainfall (snowmelt) looks to be well above normal in the west but less so in the east.

river River flows for February reflect the drier month but have no doubt made up for it since as can be seen in the recent reservoir levels which indicate above normal storage for the time of year. The  full Hydrological Summary for February is available from this link  –  February 2018 summary PDF 

Looking ahead, the experimental product from the Global Flood Awareness System suggests no enhanced flood risk, compared to the average risk, for the SW of England for the next 4 months. This is based on the early March monthly ECMWF seasonal forecast.

glofas

B: Upper Troposphere

CFS2 forecast for 200hPa suggests above normal heights across the UK and possibly reduced jet strength through Spring  but again hints at increased troughing in summer.

200

C: Lower Troposphere:

Comparing monthly data from the NMME (8th March), NCEP ensemble 10 day mean (15th March) and ECMWF (15th March) seasonal forecasts for summer 2018.

summary

Top row of each set, temperature anomaly (+ oranges). Lower row indication for above or below normal rainfall (reds are above normal in NMME and CFS2 but below normal in EC). The stronger dry signals in EC and NMME dont quite match but are clearly different to the wetter indication in the NCEP E3. There is good agreement for a colder April between NCEP and EC but not in the NMME output which tends to be a bit warm. (Note NCEP is a part of the NMME multi model ensemble).

Full size graphics and a text review of other models can be seen at www.weather-info.co.uk/wxsvc/seaslatest.html

D: Recent results/comments:

Recent seasonal models that provide month by month data were slow to pick up on the cold spell in February more than a month ahead and certainly not before the start of the winter season.  Verification details can be viewed here

summ2017 The plots above show a score out of three for the following three month forecast. ( Monthly score 0 no signal 1 poor 2 fair  and 3 good leading to a potential max of 36 for year)  This is done for each model/system for the season following the issue month. Temperature continues to be slightly better forecast than rainfall.

2. Forecast.

Remainder of Spring 2018 (April and May):

Temperatures may well start below normal in April but should recover to near normal and then above normal for May. The risk of air frosts continues into April, although probably not very frequent.

Rainfall probably below normal early April but then returning to normal with wetter spells for May especially in the west. Parts of the south and east of the region may well end up below normal for the the two months.  Snow is only likely on the tops of the moors for a time in April.

Spring climate: 1981-2010 average mean temperature 9 or 10°C but a few degrees cooler over the moors. Roughly Mar 7 or 8°C Apr 8 or 9°C  May 11 or 12°C. Average 1981 to 2010 rain 200 to 300mm lowest values in E Devon and over parts of Somerset. April is marginally wetter in western areas than May.

Summer 2018  (June July August). 

The temperature is most likely to be near or only very slightly above normal for the season. July may see larger anomalies than August.

Rainfall for the season is quite uncertain probably near or a little above the long term average but with a chance that July might be a little drier. Summer rainfall is often difficult due to showery nature leading to large variation in totals over the region. There is little agreement between the seasonal models with regards to which months might be wetter or drier.

Summer climate: 1981 to 2010 average daily mean temperature 14 or 15°C in many areas to 16 or 17°C in main urban areas also locally east of the moors and more widely in Somerset. Maximum temperatures average 19 to over 21°C in similar areas. July often warmer than August. Average 1981 to 2010 rain 300mm over the moors, typically 200 to 250mm in many coastal and eastern areas. June often drier than July and July drier than August.

Autumn 2018  (September October November) early indications. 

Temperature likely to be above normal and rainfall mostly above normal for season possibly wettest in October.

Autumn climate: 1981 to 2010 average mean temperature 11 or 12°C but nearer 10°C in rural areas. Maximum temperatures average 14 to 16°C. November normally colder than October which is colder than September. Average 1981 to 2010 rain 300 to 400mm, 600 to 800mm over the moors but east of the moors and in lowland Somerset more like 200 to 300mm . September often drier than October or November.

Winter 2018/9  (December January and February) minimal data. 

Temperature normal or above normal with variable precipitation month to month but probably ending up near normal for the season.

Winter Climate: 1981-2010 average temperature values for lowland areas 7°C in the West and 5°C in the East. Rainfall; Dec and Jan typically wetter than February. 1981-2010 Autumn average 300-400 mm lowlands but 200-300 mm areas to E of Dartmoor. Snow climatology less than 5 days lying snow over lowland areas 5 to 10 hills, say hills around 200 metre elevation – one in three years have no lying snow.

3. Caution.

Experimental Long Range Forecasts do not have a good success rate. The data used for the above forecast summary can be seen at  www.weatherservice.co.uk

The attempt at a Regional Forecast for SW England aims to test whether such a forecast of temperature and rainfall variation from average can be made using numerical model data available on the internet. The forecast should not be used for any other purpose. A brief verification summary for the UK and Eire is routinely published at http://www.weather-info.co.uk/wxsvc/Verification.html or Click here for the Teignmouth and Dawlish summary

4. References.

SST anomaly NOAA Remote Sens. 2014, 6(11), 11579-11606; doi:10.3390/rs61111579

IRI statistics: Mason, S.J. and L. Goddard, 2001: Probabilistic precipitation anomalies associated with ENSO. Bull. Amer. Meteor. Soc., 82, 619-638.

UK climate details see: http://www.metoffice.gov.uk/public/weather/climate/

NMME information:   http://journals.ametsoc.org/doi/abs/10.1175/BAMS-D-12-00050.1

CFS2  info

GLOFAS Acknowledgement: Data were provided by the Global Flood Awareness System – GloFAS (http://www.globalfloods.eu/) of the European Commission Joint Research Centre and the European Centre for Medium-Range Weather Forecasts.
Reference: Alfieri, L., Burek, P., Dutra, E., Krzeminski, B., Muraro, D., Thielen, J., and Pappenberger, F.: GloFAS – global ensemble streamflow forecasting and flood early warning, Hydrol. Earth Syst. Sci., 17, 1161-1175, doi:10.5194/hess-17-1161-2013, 2013.

‘Copernicus Products’  as listed in the C3S or CAMS Service Product Specification or any other items available through an ECMWF Copernicus  http://climate.copernicus.eu

ECMWF seasonal monthly data from weather.us

Stratospheric Diagnostics from Free University Berlin

 

Experimental Long Range Forecast for SW England. February 2018 issue.

Published 18 February 2018.

GDPR statement: Please note that the author of this blog does not set cookies but the host “wordpress.com” sets multiple cookies which are outside of the authors control. You can view their cookie policy here. 

1. Influences.

Changes in sea temperature.

anomnight.2.15.2018

Sea Temperatures have cooled relative to average around the UK and coasts of western Europe probably due to the periods of fairly strong winds from a NW direction. Elsewhere the anomalies are not very different to last month with North Atlantic anomalies still above average. Sea temperatures in the tropical Atlantic area have cooled and are forecast remain slightly below average for the next few months as shown by the UK Met Office plot below.

tropatl0218

The La Nina in the Pacific is well established (as shown by the sea temperature anomaly chart at the top of the page) with a large area of below normal sea temperatures in the eastern Pacific near the equator. The CFS2 forecast for the La Nina suggests it may continue as a week feature through summer and autumn, as shown by the graphic below (right panel). This is supported by UKMO forecast ENSO 3.4 plume but like last month the ECMWF forecast is more like the NMME consensus forecast shown below (left), which warms out the La Nina conditions.

ENSO3.4

IRI published a statistical relationship between La Nina and UK rainfall and this is shown below for March to May. The Summer comparison is not shown due to likely weakening of the La Nina.

laNinaMAMppn

IRI Spring rain probabilities during a La Nina

The plots above suggest that SW England has slightly higher probabilities of Normal to Dry conditions for Spring.

Another statistical relationship which may be playing a part in the early Spring season is the Quasi-Biennial Oscillation (QBO). The QBO is linked to conditions over Western Europe during late autumn and early winter through an influence on the phase of the North Atlantic Oscillation (NAO) at the surface. An easterly phase of the QBO tends to moderately increase the chances of a negative phase of the NAO, which in turn increases the chances of below-average temperatures.

QBO0218

QBO monitoring data (shown above) indicates that the easterly (negative) phase of the QBO has extended towards the 50hPa level and may be extending to lower levels.

The North Atlantic Oscillation index (shown by a 500hPa index in the image below) has been in the positive phase for some time but recent predictions suggest that a negative phase may develop soon.

NAO0218

For more information see Met Office NAO information.

Changes in the upper atmosphere.

The next relationship to consider is the development of sudden stratospheric warming. A major stratospheric warming episode has started and is likely to lead to a reversal of the stratospheric winds over the East Atlantic/Europe.

30hpaEC0218

30hPa ECMWF 16/1200UTC and foecast for 26/1200UTC

What is not yet clear is whether this will lead to the complete warming out of the polar vortex ending the winter mode. Forecast models do suggest that an extended anticyclonic period over parts of Northern Europe now seems more likely with impacts on temperatures across the UK.

The temperature rise at 30hPa over the N Pole is quite dramatic but the plot for 50hPa zonal mean is not outside the extremes of previous events.

Analysis and Numerical (model) output.

A: Recent Climatology.

recentclimate0218

Temperatures across the SW of England have been slightly above normal in the period November 2017 to January 2018 and it was looking as if Spring would be early. Up to mid February however, temperatures have been running at around 0.8C below the long term average.

Rainfall in parts of the region has been above normal but large areas of Devon recorded values closer to the 30 year average in the November 2017 to January 2018 period. The number of days with over 1mm was well above normal.

Recent reservoir levels indicate above normal storage for the time of year and river flows in the region also show above average values.

riverflow

The  full summary is available from the Hydrological Summary  –  January 2018 summary PDF 

An experimental product from the Global Flood Awareness System suggests no enhanced flood risk, compared to the average risk, for the SW of England for the next 4 months. This is based on the early February monthly ECMWF seasonal forecast.

0218glofas

B: Upper Troposphere

CFS2 forecast for 200hPa suggests very slightly above normal heights across the UK but and possibly reduced jet strength in Spring and perhaps hints at increased troughing in summer.

200hPa0218

C: Lower Troposphere:

Comparing monthly data from the NMME (7th Feb), NCEP ensemble 10 day mean (14th Feb) and ECMWF (12th Feb) seasonal forecasts for Spring 2018.

Top row of each set, temperature anomaly. Lower row indication for above or below normal rainfall (reds are above normal in NMME and CFS2 but in EC indicates below normal).

NMMEMAM0218

March April May 2018  NMME

NCEPMAM0218

March April May 2018 NCEP mean

ECMAM0218

There is a marked lack of agreement between the forecasting systems for Spring or Summer. Graphics for the summer months and a text review of other models can be seen at www.weather-info.co.uk/wxsvc/seaslatest.html

D: Recent results/comments:

Seasonal models were slow to pick up a trend to colder temperatures for February and possibly March 2018, despite some at least being able to resolve the atmosphere into the stratosphere. A short assessment for the November 2017 to January 2018 period of seasonal forecasts available in October 2017 can be seen at www.weather-info.co.uk/wxsvc/VerifNDJ2017.html

2. Forecast.

Spring 2018 (March April and May):

Temperature for the season is likely to be near the long term average due to a milder May despite a colder than average March and near normal values in April. The risk of air frosts continues into April, although probably not very frequent.

Rainfall probably near normal or below normal early in the season but above normal later especially in western areas. Parts of the south and east of the region may well end up below normal for the season. There is a chance of a longer drier period early in March before the weather turns more changeable either later in March or in April. Month to month detail lacks consistency between models and is often unreliable.

Some snowfall may occur early in March, chiefly over the hills and moors. The timing of the end of colder than normal temperatures is uncertain and could be as early as the first week in March limiting the snow risk.

Spring climate: 1981-2010 average mean temperature 9 or 10°C but a few degrees cooler over the moors. Roughly Mar 7 or 8°C Apr 8 or 9°C  May 11 or 12°C. Average 1981 to 2010 rain 200 to 300mm lowest values in E Devon and over parts of Somerset.

Summer 2018  (June July August). Limited model data:

The temperature is most likely to be near or only very slightly above normal for the season. August looks to have the best chance of above average temperatures.

Rainfall for the season probably near or a little above the long term average but with a chance that July might be a little drier and August wetter. Summer rainfall is often difficult due to showery nature leading to large variation in totals over the region. There is little agreement between the seasonal models with regards to which months might be wetter or drier.

Summer climate: 1981 to 2010 average daily mean temperature 14 or 15°C in many areas to 16 or 17°C in main urban areas also locally east of the moors and more widely in Somerset. Maximum temperatures average 19 to over 21°C in similar areas. July often warmer than August. Average 1981 to 2010 rain 300mm over the moors, typically 200 to 250mm in many coastal and eastern areas. June often drier than July and July drier than August.

3. Caution.

Experimental Long Range Forecasts do not have a good success rate. The data used for the above forecast summary can be seen at  www.weatherservice.co.uk

The attempt at a Regional Forecast for SW England aims to test whether such a forecast of temperature and rainfall variation from average can be made using numerical model data available on the internet. The forecast should not be used for any other purpose. A brief verification summary for the UK and Eire is routinely published at http://www.weather-info.co.uk/wxsvc/Verification.html or Click here for the Teignmouth and Dawlish summary

4. References.

SST anomaly NOAA Remote Sens. 2014, 6(11), 11579-11606; doi:10.3390/rs61111579

IRI statistics: Mason, S.J. and L. Goddard, 2001: Probabilistic precipitation anomalies associated with ENSO. Bull. Amer. Meteor. Soc., 82, 619-638.

UK climate details see: http://www.metoffice.gov.uk/public/weather/climate/

NMME information:   http://journals.ametsoc.org/doi/abs/10.1175/BAMS-D-12-00050.1

CFS2  info

GLOFAS Acknowledgement: Data were provided by the Global Flood Awareness System – GloFAS (http://www.globalfloods.eu/) of the European Commission Joint Research Centre and the European Centre for Medium-Range Weather Forecasts.
Reference: Alfieri, L., Burek, P., Dutra, E., Krzeminski, B., Muraro, D., Thielen, J., and Pappenberger, F.: GloFAS – global ensemble streamflow forecasting and flood early warning, Hydrol. Earth Syst. Sci., 17, 1161-1175, doi:10.5194/hess-17-1161-2013, 2013.

‘Copernicus Products’  as listed in the C3S or CAMS Service Product Specification or any other items available through an ECMWF Copernicus  http://climate.copernicus.eu

ECMWF seasonal monthly data from weather.us

Stratospheric Diagnostics from Free University Berlin

 

Experimental Long Range Forecast for SW England. Update to January 2018 issue.

Published 4 February 2018.

Update.

Expected changes in the stratosphere illustrated by the ECMWF 30hPa sequence shown below may lead to an extension of “Winter” into early March due to increased chance of blocking and colder surface winds from an Easterly point.

030218SSW30hpa

This change may have been predicted by UKMO contingency forecast for February which suggested a colder and drier than normal February. Cansips (issued 31st Jan) hints at normal and locally colder temperatures for February. CFSv2 suggests colder and drier weather types for February and these may extend into the first half of March.

temprainseasonal

Forecast update.

The chance of a colder and drier February and start March for SW England is more likely than previously.

Caution.

Experimental Long Range Forecasts do not have a good success rate. The data used for the above forecast summary and brief verification of previous Long Range Forecast summaries can be seen at   http://www.weatherservice.co.uk

The attempt at a Regional Forecast for SW England aims to test whether such a forecast of temperature and rainfall variation from average can be made using numerical model data available on the internet. The forecast should not be used for any other purpose. A brief verification summary for the UK and Eire is routinely published at http://www.weather-info.co.uk/wxsvc/Verification.html or Click here for the Teignmouth and Dawlish summary

References.

CFS2  info

Stratospheric Diagnostics from Free University Berlin

 

Experimental Long Range Forecast for SW England. January 2018 issue.

Published 17 January 2018.

1. Influences.

Changes in sea temperature.

SSTanom150118

Sea Temperatures are slightly cooler than average around the UK and coasts of western Europe but elsewhere the anomalies are similar to last month with Atlantic anomalies still above normal. Sea temperatures in the tropical Atlantic area are forecast to remain slightly above normal, as shown in the UK Met Office plot below.

160118tropnatl

The La Nina in the Pacific is well established, with a large area of below normal sea temperatures in the eastern Pacific, south of the equator. The CFS2 forecast for the La Nina suggests it may continue as a week feature through summer and autumn, as shown by the graphic below (left). This is supported by UKMO forecast ENSO plume but ECMWF is similar to the NMME consensus forecast shown below (right), which warms out the La Nina condithions.

nino160118

IRI published a statistical relationship between La Nina and UK rainfall and this is shown below for March to May. The Summer comparison is not shown due to likely weakening of the La Nina.

laNinaMAMppn

Probability for Dry/Normal/Wet based on a La Nina being active

The plots above suggest that SW England has slightly higher probabilities of Normal to Dry conditions for Spring.

Another statistical relationship which may play a part in the remainder of the Winter and for the Spring season is the Quasi-Biennial Oscillation (QBO). The QBO is linked to conditions over Western Europe during late autumn and early winter through an influence on the phase of the North Atlantic Oscillation (NAO) at the surface. An easterly phase of the QBO tends to moderately increase the chances of a negative phase of the NAO, which in turn increases the chances of below-average temperatures.”

QBO

QBO monitoring data (shown above) indicates that the easterly (negative) phase of the QBO remains above 50hPa and has had little impact this winter.

The North Atlantic Oscillation index (shown by a 500hPa index in the image below) has been in the positive phase for some time and ensemble predictions suggest that a weak positive phase will continue, maintaining the signal for a  milder/wetter remainder of winter.

160118NAO

For more information see Met Office NAO information.

The next relationship to consider is the potential for the development of a sudden stratospheric warming. Should this occur there can be an impact on the Jet stream causing it to weaken and allowing High pressure to develop over Europe. This could bring colder temperatures further west and possibly into the UK. To date there has been periods of warming over the N Pacific and into northern Canada. The stratospheric polar vortex was displaced eastwards but then redeveloped further west resulting in a drop in North Pole 30hPa temperatures (shown below).

30hpa

Over recent weeks there have been a series of minor warming event across the N Pacific and into Canada with some model runs splitting the polar vortex, which might have been a prelude to a change away from the mobile westerly types currently affecting western Europe/Uk area. More recent ECMWF model runs have moved away from this idea and maintained a strong vortex although again being displaced further east away from the pole.

ecmwf30a12

ECMWF 30hPa T+00 +120 and +240 hours from 16th Jan 2018

Stratospheric temperatures in the North Polar vortex have been low enough for the formation of Polar Stratospheric clouds which are implicated in Ozone destruction. Should the vortex be maintained this could become an item of interest this Spring.

50hpa

Left Total Ozone. Right 50hPa minimum temperature plot.

 

Analysis and Numerical (model) output.

A: Recent Climatology.

temp

Temperatures across the SW of England have been slightly above normal and for many areas the last four months have been slightly drier, despite a wetter December.  January in SW England so far is running slightly milder than average, wetter in the west but drier in the east (based on limited data).

Recent reservoir levels remain above normal for the time of year and river flows in the region have returned to near average values.

Decriver

The  full summary is available from the Hydrological Summary  –  December 2017 summary PDF 

An experimental product from the Global Flood Awareness System suggests the flood risk areas for the next 4 months based on January ECMWF seasonal forecast.Glofass

For the SW of England the river flood risk does not appear to be elevated compared to normal with the main risk areas across Eire/N Ireland and N England/S Scotland.

B: Upper Troposphere:

z200

CFS2 forecast for 200hPa suggest above normal heights across the UK but still with a signal for enhanced jet across the Atlantic for a time in Spring.

C: Lower Troposphere:

Comparing the CFS2 mean of 10 days forecasts and the NMME output for Spring 2018. Top row of each pair, temperature anomaly. Lower row indication for above or below normal rainfall (reds are above).

mamcomp

NMME forecast for Summer 2018.jjacomp

The forecasts tend to be a little warm and the rainfall output is often poor with month to month detail. The below average rainfall in the S of UK does fit to some extent with the IRI probabilities when experiencing a La Nina in the Pacific.

D: Subjective model scores for temperature and rainfall for the seasonal forecasts issued December 2016 to September 2017 valid for the following three months. (e.g. September forecast valid for Oct Nov Dec). Left hand column is total of all months where there is a potential max score of 30. Scores for rainfall show only a few good forecasts.

verif

2. Forecast.

Remainder of Winter ( 2018 February) :

There are strong indications for a milder than average February in the SW of England.  This does not rule out some colder spells, probably with North or NW winds rather than easterly, but suggests that the cold spells will be short lived.

Mobile westerly patterns look like continuing to dominate the weather leading to above normal  rainfall especially in Cornwall and in areas to the west of the Moors. Elsewhere near normal or slightly above normal rain totals are most likely. The snow risk remains reduced compared to average with little if any snow for lower ground but some snow for the moors.

February Climate: 1981-2010 Temperature; average temperature values for lowland areas 5 or 6°C but over 6°C in West Cornwall. Rainfall;  February. 1981-2010 average 80-100mm mm lowlands but 60-80mm in areas to E of Dartmoor and 40-80mm East of Exmoor. Over the Moors 100-250mm. 

Spring 2018 (March April and May):

Temperature for the season is likely to be near or a little above the long term average. There are, however, hints of a colder spell which is more likely in April than the other months. Risk of air frost continues into April though not very frequent.

Rainfall probably near normal but in the south and east of the region rain totals may well be below normal. Although a mostly unsettled theme is likely there is a chance of a longer drier period sometime later in March or in April. Month to month detail lacks consistency between models and is often unreliable.

Spring climate: 1981-2010 average mean temperature 9 or 10°C but a few degrees cooler over the moors. Roughly Mar 7 or 8°C Apr 8 or 9°C  May 11 or 12°C. Average 1981 to 2010 rain 200 to 300mm lowest values in E Devon and over parts of Somerset.

Summer 2018  (June July August). Limited model data:

The average temperature is most likely to be near or only slightly above normal for the season. During August there is the best chance of above average temperatures.

Rainfall for the season probably below the long term average (in terms of number of wet days, if not actual rain totals) but with a chance that August could see above normal rainfall. Summer rainfall is often difficult due to showery nature leading to large variation in totals over the region.

 

Summer climate: 1981 to 2010 average daily mean temperature 14 or 15°C in many areas to 16 or 17°C in main urban areas also locally east of the moors and more widely in Somerset. Maximum temperatures average 19 to over 21°C in similar areas. July often warmer than August. Average 1981 to 2010 rain 300mm over the moors, typically 200 to 250mm in many coastal and eastern areas. June often drier than July and July drier than August.

3. Caution.

Experimental Long Range Forecasts do not have a good success rate. The data used for the above forecast summary and brief verification of previous Long Range Forecast summaries can be seen at   http://www.weatherservice.co.uk

The attempt at a Regional Forecast for SW England aims to test whether such a forecast of temperature and rainfall variation from average can be made using numerical model data available on the internet. The forecast should not be used for any other purpose. A brief verification summary for the UK and Eire is routinely published at http://www.weather-info.co.uk/wxsvc/Verification.html or Click here for the Teignmouth and Dawlish summary

4. References.

SST anomaly NOAA Remote Sens. 2014, 6(11), 11579-11606; doi:10.3390/rs61111579

IRI statistics: Mason, S.J. and L. Goddard, 2001: Probabilistic precipitation anomalies associated with ENSO. Bull. Amer. Meteor. Soc., 82, 619-638.

UK climate details see: http://www.metoffice.gov.uk/public/weather/climate/

NMME information:   http://journals.ametsoc.org/doi/abs/10.1175/BAMS-D-12-00050.1

CFS2  info

GLOFAS Acknowledgement: Data were provided by the Global Flood Awareness System – GloFAS (http://www.globalfloods.eu/) of the European Commission Joint Research Centre and the European Centre for Medium-Range Weather Forecasts.
Reference: Alfieri, L., Burek, P., Dutra, E., Krzeminski, B., Muraro, D., Thielen, J., and Pappenberger, F.: GloFAS – global ensemble streamflow forecasting and flood early warning, Hydrol. Earth Syst. Sci., 17, 1161-1175, doi:10.5194/hess-17-1161-2013, 2013.

‘Copernicus Products’  as listed in the C3S or CAMS Service Product Specification or any other items available through an ECMWF Copernicus  http://climate.copernicus.eu

Stratospheric Diagnostics from Free University Berlin

 

Experimental Long Range Forecast for SW England. December 2017 issue.

Published 18 December 2017.

1. Influences.

Changes in sea temperature.

sstanom141217

Apart from a little cooling, relative to “normal”, near the North of Scotland Atlantic anomalies continue to be above normal. The tropical area is forecast to remain slightly above normal as shown in the UK Met Office plot below (right). The La Nina in the Pacific is well established, with a large area of below normal sea temperatures in the eastern Pacific south of the equator. The La Nina is forecast to slowly decline during the Spring and early Summer as shown by the NMME plot below (left).

tropsst1

IRI published a statistical relationship between La Nina and UK rainfall and this is shown below for January to May, however, as the La Nina becomes weak so the statistical relationship may decline.

JFMMAMlaNinprobs

IRI probabilities of Wet /Normal /Dry seasons based on possible links to La Nina

The plots above suggest that SW England has slightly higher probabilities of Normal to Dry conditions as we move into Spring.

Another statistical relationship which may play a part in the remainder of the Winter and Spring seasons is the Quasi-Biennial Oscillation (QBO). The QBO is linked to conditions over Western Europe during late autumn and early winter through an influence on the phase of the North Atlantic Oscillation (NAO) at the surface. An easterly phase of the QBO tends to moderately increase the chances of a negative phase of the NAO, which in turn increases the chances of below-average temperatures.”

qbo

QBO monitoring data (shown above) indicates that the easterly (negative) phase of the QBO remains above 50hPa.

The North Atlantic Oscillation index (shown by a 500hPa index in the image below) continues to oscillate between positive and negative phases with ensemble predictions of remaining in a positive phase through to the end of December. This maintains a signal for a  milder/wetter winter season to develop.

nao181217

The North Atlantic Oscillation can also be affected by the Madden-Julian Oscillation. In an early issue of the contingency forecast (15 December 2017), the Met Office states that “the Madden-Julian Oscillation is an area of enhanced thundery activity that moves eastwards through the tropics over a period of several weeks. It has recently been active and is currently in a location that frequently leads to a negative phase of the North Atlantic Oscillation about 10 days later. The negative phase of the NAO brings colder-than average conditions to the UK, implying an increased chance of colder than-average temperatures in early January.” For more information see Met Office NAO information.

The next statistical relationship to consider is the development of a sudden stratospheric warming. Should this occur there can be an impact on the Jet stream causing it to weaken and allowing High pressure to develop over Europe. This could bring colder temperatures further west and possibly into the UK.

The stratospheric polar vortex has been displaced eastwards over recent weeks by a series of warming events across the N Pacific and into Canada, as can be seen in the temperature plot for the North Pole.

pole30_nh

It is not clear whether there will be a full disruption of the polar vortex, though this remains a risk, possibly leading to an upset in the model forecasts. Several of the seasonal models are able to handle changes in the stratosphere.

30hpa

ECMWF 30hPa chart 17 December and forecast for 27 December 2017

Analysis and Numerical (model) output.

A: Recent Climatology.

tandr181217Nov

Temperatures across the SW of England have been near normal and for many areas it has been a fairly dry period. Recent reservoir levels remain above normal for the time of year, but further dry weather may impact the storage levels for the winter as a whole.  River flows in the region for the Autumn season show western areas above normal and eastern areas below, although November data shows reduced river flow in more areas.

riverflowsNov2017

The  full summary is available from the Hydrological Summary  –  November 2017 summary PDF 

An experimental product from the Global Flood Awareness System suggests the flood risk areas for the next 4 months based on ECMWF seasonal forecast.

181217riverflow

Hint at below normal river flows in Somerset and high flows in the Exe estuary, the latter looking odd. Compared to the previous forecast there is a lower probability of flooding in some Wales and N England.

B: Upper Troposphere:

z200JFM1117

CFS2  200hPa monthly mean Jan Feb March 2017 and anomalies (lower)

z200MAM1217

CFS2 200hPa monthly mean contour March April May 2017 and (lower) anomalies

CFS2 forecast for 200hPa suggest above normal heights across the UK but still with a signal for enhanced jet across the Atlantic in February.

C: Lower Troposphere:

Comparing the CFS2 mean of 10 days forecasts (top row of each pair temperature anomaly, lower row indication for above or below normal rainfall (reds are above).

cfandnmmjfm2017

Jan Feb March 2017 temperature and precipitation anomalies

cfandnmmmam2017

March April May Temperature and rainfall anomalies

The main theme from the above is for above normal temperatures and a wet period early in 2018 but a drier Spring with temperatures nearer normal, for at least some of the months.

D: Comment:  Seasonal temperature and rainfall forecast data for the Autumn have tended to over forecast above normal temperature and rainfall. There has been some indications of below normal rain in southern areas but these have not been consistent. Forecasts of below normal temperature seem to be rare in the model output. So far in December temperatures have been near or slightly below average and the rainfall about half of the total for a normal month but this can easily change. Verification summary.

2. Forecast.

Remainder of Winter ( 2018  January and February) :

There remains a strong indication for a milder than average January and February in the SW of England  This does not rule out some colder spells, probably with North or NW winds rather than easterly, but suggests that the cold spells will be short lived.

Rainfall is uncertain month to month but the suggestion that mobile westerly patterns will come to dominate the weather patterns suggests above normal  rainfall especially in Cornwall and to the west of the moors. Elsewhere near normal or even slightly below normal rainfall seems possible, perhaps with January being the wetter month. The snow risk is reduced compared to average with little if any snow for lower ground but some snow for the moors.

Due to the statistical relationships, outlined in part 1, there is a moderate risk that colder and drier weather may develop making this forecast summary uncertain.

Winter Climate: 1981-2010 average temperature values for lowland areas 7°C in the West and 5°C in the East. Rainfall;  January typically wetter than February. 1981-2010 Autumn average 300-400 mm lowlands but 200-300 mm areas to E of Dartmoor. Snow climatology less than 5 days lying snow over lowland areas 5 to 10 hills, say hills around 200 metre elevation – one in three years have no lying snow.

Spring 2018 (March April and May):

Temperature probably slightly above normal for the season but possible colder periods in March and again in May. Rainfall near normal in the west, elsewhere drier than average.

Spring climate: 1981-2010 average mean temperature 9 or 10°C but a few degrees cooler over the moors. Roughly Mar 7 or 8°C Apr 8 or 9°C  May 11 or 12°C. Average 1981 to 2010 rain 200 to 300mm lowest values in E Devon and over parts of Somerset.

Summer 2018  (June July August). Limited model data:

Temperatures near normal, perhaps a cooler start and a warmer end to summer compared to average. Uncertain rainfall but perhaps above normal in June and near normal later.

Summer climate: 1981 to 2010 average daily mean temperature 14 or 15°C in many areas to 16 or 17°C in main urban areas also locally east of the moors and more widely in Somerset. Maximum temperatures average 19 to over 21°C in similar areas. July often warmer than August. Average 1981 to 2010 rain 300mm over the moors, typically 200 to 250mm in many coastal and eastern areas. June often drier than July and July drier than August.

3. Caution.

Experimental Long Range Forecasts do not have a good success rate. The data used for the above forecast summary and brief verification of previous Long Range Forecast summaries can be seen at   http://www.weatherservice.co.uk

The attempt at a Regional Forecast for SW England aims to test whether such a forecast of temperature and rainfall variation from average can be made using numerical model data available on the internet. The forecast should not be used for any other purpose. A brief verification summary for the UK and Eire is routinely published at http://www.weather-info.co.uk/wxsvc/Verification.html or Click here for the Teignmouth and Dawlish summary

4. References.

SST anomaly NOAA Remote Sens. 2014, 6(11), 11579-11606; doi:10.3390/rs61111579

IRI statistics: Mason, S.J. and L. Goddard, 2001: Probabilistic precipitation anomalies associated with ENSO. Bull. Amer. Meteor. Soc., 82, 619-638.

UK climate details see: http://www.metoffice.gov.uk/public/weather/climate/

NMME information:   http://journals.ametsoc.org/doi/abs/10.1175/BAMS-D-12-00050.1

CFS2  info

GLOFAS Acknowledgement: Data were provided by the Global Flood Awareness System – GloFAS (http://www.globalfloods.eu/) of the European Commission Joint Research Centre and the European Centre for Medium-Range Weather Forecasts.
Reference: Alfieri, L., Burek, P., Dutra, E., Krzeminski, B., Muraro, D., Thielen, J., and Pappenberger, F.: GloFAS – global ensemble streamflow forecasting and flood early warning, Hydrol. Earth Syst. Sci., 17, 1161-1175, doi:10.5194/hess-17-1161-2013, 2013.

‘Copernicus Products’  as listed in the C3S or CAMS Service Product Specification or any other items available through an ECMWF Copernicus  http://climate.copernicus.eu

Stratospheric Diagnostics from Free University Berlin