Winter Forecast 2014/2015
By Ed O’Toole and Tony Wells.
This forecast is based on certain solar, atmospheric and sea state conditions that are in place prior to the start of this winter. These conditions will be examined in turn, but ultimately they will lead to atmospheric responses that are likely to influence the forthcoming winter pattern.
Overall the key conclusions are that winter will have the following characteristics:
- Slightly colder than average.
- Around average rainfall but conditions favour wetter further south and drier to the north of the UK.
- December likely to be the most unsettled month with the risk of a significant wind event (though less so compared to last year).
- February the most settled and driest month.
- Late December and into January is most likely to herald a significant wintry spell, though other major cold snaps throughout the winter are likely as well.
- Most of the UK likely to see some settling snow at some point.
- Overall Winter CET of 3.5-4°c.
- December CET forecast: 4-4.5°c.
- January CET forecast: 3-3.5°c.
- February CET forecast: 3.5-4.5°c.
These conditions are likely to be caused by:
- A mean negative Arctic Oscillation (AO) throughout winter of around -1. (AO description here.)
- Positive height anomalies to the north leading to significant high latitude blocking.
- A weakened stratospheric vortex with a Sudden Stratospheric Warming (SSW) likely around the turn of the year leading to a very disturbed tropospheric polar vortex and negative NAO around this time.
- A southerly displaced jet stream. (Jet stream tutorial.)
In depth and technical forecast
This is an overview of the full winter forecast, please click below to view the full (technical) version:
Winter Outlook - In Depth