Developments high up in the stratosphere can impact on our weather.
In the winter months a Sudden Stratospheric Warming (SSW) increases the chance of cold weather in mid-latitude locations such as the UK.
The stratosphere temperature and zonal wind forecast charts help show whether an SSW is forecast or is happening.
These charts show a flattened view of the northern hemipshere with the north pole in the centre.
The purple donut shape indicates the Stratosperic Polar Vortex (SPV). If an SSW takes place and the SPV is disrupted or destroyed the chance of cold weather in the UK is increased.
GFS 10hPa wind forecast for t+180 hours. Using GFS 00z run.
GFS 10hPa wind forecast for t+384 hours. Using GFS 00z run.
View for all time steps
GEFS is an ensemble model which means it is run many times to help account for uncertainty.
Each line on the charts represents the forecast from one of the GEFS runs for the next 16 days.
The GFS run (which the above charts are produced from) is also shown and is labelled "OPERATIONAL"
If an SSW is forecast the zonal wind speeds will fall sharply and may become negative.
GEFS 10hPa zonal wind forecast at 60° north for the next 16 days.
GEFS 10hPa zonal wind forecast at 60° north for the next 35 days.
GEFS 10hPa zonal wind forecast at 70° north for the next 16 days.
If an SSW is forecast the temperatures will rise rapidly. They can increase by as much as 60C in a few days.
GEFS 10hPa mean temperature forecast at 60° north for the next 16 days.
GEFS 10hPa mean temperature forecast at 60° north for the next 35 days.
GEFS 10hPa mean temperature forecast at 70° north for the next 16 days.
Glastonbury Festival 2023 weather
Download Festival 2023 weather
Summer 2023 second update
Stay ahead of the weather this summer
Voice control available
Daily weather by email
14 day outlook
A huge range of charts and data is freely available.
Models include UK Met Office UKV and MOGREPS-G, ECMWF, NCEP GFS, Meteo France Arpege and Arome.