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The EFI values were above 90% more than 3 days in advance. High values of the EFI and SOT show pretty well the potential of extreme rainfall in the affected areas. For the ENS the extreme rainfall values were lower compared to HRES.
The plot below show EFI and SOT for precipitation on 5 December in forecasts from 3- days before the event.
3.4 Monthly forecasts
Verification of the monthly forecast valid the week 30 November - 6 December. The forecast from two weeks before the event had a wet signal for the northern British Isles and southern Norway. The early signal was connected to the prediction of a positive NAO phase, as seen in the MSLP anomalies below.
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