Monday, October 17th 2011, 2:21 PM EDT
The North South split, in particular the sunny and warmer than normal weather in the South / East of Britain for most of ~12-16 Oct has been well confirmed. 17th Oct also looks like being warmer than normal in Southeast England and the expected change to cooler on 18th in the forecast graph is also coming – to the day.
However the return to warm weather originally expected for 19-20th will have been knocked out by the very active 17-18th Extra Top Red period - the expected brief return of High pressure being too weak.
This means: -
1. The 19-20th will be cold everywhere in Britain & Ireland, not warm.
2. The closer proximity of Low centres to Britain around 19-20th increases confidence of major storm activity being nearer or over N/East Britain in the North Sea storm threat period 21-23 Oct.
This increases the risk of serious attacks to N sea coasts of Denmark, NW Germany & N Holland AND increases danger for East England coasts, although the threat level there remains lower than the pounding the sea will deliver to continental coasts.
Sea defences leakage is likely in EastEngland but the probability of overtopping (the Moon not being helpful this time) is not more than about 25%.
3 Although there will be some snow on High ground in Scotland from ~ 19th this is not really much out of the ordinary for this time of year. WeatherAction’s main expectation for some snow (but still not a major amount) mainly in NorthEast remains as 24th-27th.