01-10-2016 | Estofex | m.b.t. 02-10-2016 t/m 03-10-2016
A level 1 was issued for parts of the North Sea and the near coastal areas of the Netherlands as well as the East and West Frisian Islands, mainly for tornadoes.
Storm Forecast
Valid: Sun 02 Oct 2016 06:00 to Mon 03 Oct 2016 06:00 UTC
Issued: Sat 01 Oct 2016 17:34
Forecaster: BEYER
A level 1 was issued for parts of the North Sea and the near coastal areas of the Netherlands as well as the East and West Frisian Islands, mainly for tornadoes.
SYNOPSIS
A trough is active over most parts of Central and North Europe. Its southernmost part detaches during the forecast period and forms an upper level low centered over Northern Germany and Denmark. Cold upper level airmasses lead to an unstable environment.
Western and Northwestern Europe are mainly under the influence of a well amplified ridge on the forward flank of a new long wave trough over the Eastern North Atlantic. Stable and warm airmasses are increasingly advected with a southerly component.
Apart from the Aegean Sea most regions of the Mediterranean still have to struggle with an unstable environment. The trough on the southern flank of the addressed upper level low over Northern Germany influences Southern Europa. Its main axis travels from Sardinia at the beginning of the forecast period to the Eastern Balkan Peninsula at its end. However, it is not easy to anticipate a strict axis since the general flow is rather zonal showing several short wave features.
In the second half of the forecast time Southwestern Europa and the Western Mediterranean are getting under the influence of a shallow ridge and thus under stable conditions.
DISCUSSION
...North Sea and the near coastal areas of the Netherlands and the Frisian islands...
Under the center of the upper level low quite weak mid and upper level winds are present. With the available cold airmasses quite steep mid and low level lapse rates are present whereas the latter is mainly due to the warm ocean and daytime heating over land, respectively.
This finally leads to robust LL CAPE values of more than 100 J/kg that enhance significantly the threat for waterspouts. The risk area is mainly coupled to the time of the day and the sea breeze front. During night the waterspouts should mainly be active over sea, however during the day also the coastal areas of the Netherlands and the Frisian islands are under the threat level, when the sea breeze front moves inland.
The overall threat travels with the upper level low slowly eastward during the forecast period.
(alleen de voor NL en direct aangrenzende gebieden relevante tekstdelen overgenomen, klik hier voor de volledige forecast, red.)
Tornado/hoosverschijnsel(en) | Verwachtingen/waarschuwingen