01-08-2019 20:05 | Estofex | m.b.t. 02-08-2019 t/m 03-08-2019
Storm Forecast
Valid: Fri 02 Aug 2019 06:00 to Sat 03 Aug 2019 06:00 UTC
Issued: Thu 01 Aug 2019 20:05
Forecaster: PISTOTNIK
Level 3 areas are issued for small parts of NE Italy, Croatia and Bosnia-Herzegovina mainly for large hail, severe convective wind gusts and to a lesser extent for tornadoes.
A level 1 and level 2 is issued for N Italy, S Austria, SW Hungary, Slovenia, Croatia and Bosnia-Herzegovina, Montenegro, Serbia and W Romania for large hail and severe convective wind gusts (mainly in its S half) and for excessive convective precipitation (mainly in its N half).
A level 1 and level 2 are issued for E Romania mainly for large hail, excessive convective precipitation and to a lesser degree severe convective wind gusts.
A level 1 is issued for the Netherlands and NW Germany for excessive convective precipitation.
SYNOPSIS
The main frontal zone runs on a quite southerly position between 45N and 50N from the Ukraine across the Alpine region to the Bay of Biscay. To its north, low-pressure systems are centered over NW Russia and over the N Atlantic west of Ireland. In-between, a formerly blocking Arctic high slips south towards the British Isles, but gradually flattens without interrupting the main frontal zone too much.
Steep lapse rates and rich low-level moisture overlap to the south of the frontal zone, in particular beneath an elevated mixed layer (EML) that is spreading from NW Africa to Italy and towards the Balkans. Cooler maritime air with adequate moisture but weaker lapse rates is present to its north. Finally, cold and dry air spreads into Scandinavia and NE Europe in the wake of the Russian cyclone.
DISCUSSION
... Netherlands, Germany, Czech Republic, N Austria ...
Some hundred J/kg CAPE form in response to daytime heating on the cool side of the frontal zone. Scattered storms may already be active in the morning over the Netherlands, where a mesoscale cyclone (possibly even with a shallow warm core) moves onshore. Isolated waterspouts are not ruled out near the center of this cyclone or in the German Bight, which may also see morning showers.
In the late morning to afternoon, scattered convection will initiate further inland. Slow storm motion under weak vertical wind shear can promote a few excessive rain events. Towards the south, deep-layer shear increases to 15 m/s and convection over the Bohemian Massif (bordering region of Germany, the Czech Republic and Austria) can organize into multicells and possibly one or two transient supercells. In that case, marginally large hail and isolated severe wind gusts become additional risks.
Convection will mostly decay in the evening.
(alleen de voor NL en aangrenzende gebieden relevante tekstdelen zijn overgenomen, klik hier voor de volledige forecast, red.)
Verwachtingen/waarschuwingen
