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The plot below shows the warnings on Meteoalarm from 5 October, with a red warning for wind gusts over northern Germany.



2.2 Mesoscale

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Satellite and radar sequences around the time that the maximum gusts hit Berlin both suggest, via filamentation in the cloud head region, that the gusts could well have been due to the "Sting Jet" phenomena. The fact that the gusts inland were so high is also believed to be a characteristic of sting jets, because of the top-down destabilisation mechanism that is believed to be involved (as on the "3D visualisation" poster below).

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The following plots place short range max gust predictions from HRES into the context of the vertical profiles of wind, T and Td. 13UTC was chosen from this run as the time with the maximum over-land gusts. Although this time does not coincide exactly with the time of maximum gusts over Berlin, the data are believed to be indicative of the atmospheric characteristics over Berlin (and indeed other areas in N Germany) when the peak gusts were occurring. Correctly pinpointing details in these finely balanced situations is always difficult for models.


Maximum instantaneous gusts in short range HRES run, at T+13=VT 13Z on 5 October 2017, right panel has HRES Tephigram locations added

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