Status:Ongoing analysis Material from: Linus, ..
1. Impact
On 17-21 October a cyclone named Babet caused widespread impact from Portugal up to Denmark/Norway. Among the worst affected areas were Scotland with extreme rainfall causing 7 fatalities. In eastern Denmark record breaking storm surge was observed in the strong easterly wind north of the cyclone.
https://en.wikipedia.org/wiki/Storm_Babet
2. Description of the event
The plots below show analyses of MSLP and 6 hour rainfall from 17 October 00UTC to 22 October 00UTC, every 12th hour.
3. Predictability
3.1 Data assimilation
3.2 HRES
The plots below show 24-hour precipitation (19 October 00UTC - 20 October 00UTC) in observations (first plot) concatenated short forecasts (second plot) and ENS control forecasts with different lead times. The box marks 0.5x0.5 degree centred over Angus, Scotland.
3.3 ENS
The plots below shows EFI and SOT for 1-day precipitation (19 October 00UTC - 20 October 00UTC) from different initial dates.
The plot below shows the forecast evolution plot for 24-hour precipitation (19 October 00UTC - 20 October 00UTC) a 0.5x0.5 box around Angus, Scotland (centred on 56.9N, 2.9W). Concatenated 6-hour forecasts - green dot, ENS control –red, ENS blue box-and-whisker, Model climate – cyan box-and-whisker. Ensemble mean as black diamonds. Triangle marks the maximum in the model climate based on 1600 forecasts. One can see a sharp increase in signal on 14 October.
During 18-20 October large parts of western Europe was covered by extreme rainfall, as seen in the 3-day EFI map below from 18 October. The next forecast evolution plot shows the mean 3-day precipitation over land point inside the box of 35N-60N, 10W-10E. The plot includes concatenated 6-hour forecasts - green dot, ENS control –red, ENS blue box-and-whisker, Model climate – cyan box-and-whisker. Ensemble mean as black diamonds. Triangle marks the maximum in the model climate based on 1800 forecasts. One can see in the shortest forecast that all ensemble members exceeded the maximum value in the model climatology (for this time of the year). The signal was picked up gradually in the from 10 October and onwards.
