Status: Finalised Material from: Linus, Tim
Picture
1. Impact
A Channel cyclone referenced named "Egon" by the Free University of Berlin, delivered some snow disruption across SE England on the evening of 12 January, with areas S of London apparently most affected, and also, more significantly, some extreme winds in the English Channel, over NE France, and to a lesser extent further east. 330,00 homes were left without power in France.
2. Description of the event
If one classifies storm severity by max 6h deepenig, it is clear that this storm ranks alongside some of the most severe of the last 30 years. Most storms had more extreme winds associated, although peak gusts over N France exceeded 70kts inland, locally, in the path of what appears to have been a sting jet that developed late yesterday afternoon and continued into the evening (though this presumption is based only a brief investigation).
Met Office analysis chart for 12Z and Met Office analysis chart for 18Z
IR sequence. Note fingers of cold top cloud projecting forward from the tip of the cloud head, near to 50N, which is commonly a symptom of a sting jet.
Radar sequence at 25min intervals for mid afternoon. Low is in the Channel moving east, with cold air on the N flank. Red dot is ECMWF.
Some French warnings on meteoalarm were updated from amber to red mid afternoon. It looks as though there were previously no wind warnings in operation in NE France, but this is wrong and is due to a 'bug' in the meteoalarm map display.
3. Predictability
3.1 Data assimilation
3.2 HRES
The plots below shows 24-hour maximum wind gusts from 12 January 12z to 13 January 12z from observations (first plots) and HRES forecasts from different initial times.
3.3 ENS
The plots below shows cyclone feature product for maximum wind speed within 300 km radius valid 13 January 00z.
3.4 Monthly forecasts
3.5 Comparison with other centres
4. Experience from general performance/other cases
5. Good and bad aspects of the forecasts for the event
6. Additional material
Status:Ongoing analysis Material from: Linus, Tim
Picture
1. Impact
A Channel cyclone referenced named "Egon" by the Free University of Berlin, delivered some snow disruption across SE England on the evening of 12 January, with areas S of London apparently most affected, and also, more significantly, some extreme winds in the English Channel, over NE France, and to a lesser extent further east. 330,00 homes were left without power in France.
2. Description of the event
If one classifies storm severity by max 6h deepenig, it is clear that this storm ranks alongside some of the most severe of the last 30 years. Most storms had more extreme winds associated, although peak gusts over N France exceeded 70kts inland, locally, in the path of what appears to have been a sting jet that developed late yesterday afternoon and continued into the evening (though this presumption is based only a brief investigation).
Met Office analysis chart for 12Z and Met Office analysis chart for 18Z
IR sequence. Note fingers of cold top cloud projecting forward from the tip of the cloud head, near to 50N, which is commonly a symptom of a sting jet.
Radar sequence at 25min intervals for mid afternoon. Low is in the Channel moving east, with cold air on the N flank. Red dot is ECMWF.
Some French warnings on meteoalarm were updated from amber to red mid afternoon. It looks as though there were previously no wind warnings in operation in NE France, but this is wrong and is due to a 'bug' in the meteoalarm map display.
3. Predictability
3.1 Data assimilation
3.2 HRES
The plots below shows 24-hour maximum wind gusts from 12 January 12z to 13 January 12z from observations (first plots) and HRES forecasts from different initial times.
3.3 ENS
The plots below shows cyclone feature product for maximum wind speed within 300 km radius valid 13 January 00z.
1 Comment
Thomas Schumann
Well done
Thomas