Storm Forecast
Valid: Fri 31 Jan 2020 06:00 to Sat 01 Feb 2020 06:00 UTC
Issued: Fri 31 Jan 2020 00:22
Forecaster: PISTOTNIK
A level 1 is issued for SE Turkey, Syria and Iraq for severe convective wind gusts, excessive convective precipitation and to a lesser extent for tornadoes.
SYNOPSIS
A polar trough filled with cold air has amplified from Finland to Turkey and moves east. In its wake, a shallow ridge travels eastward across central Europe before a very strong W-erly flow establishes again from the British Isles to Poland. In the warm sectors of two storm cyclones over the Norwegian Sea and the North Atlantic, very mild and moist maritime air overspreads central Europe and the British Isles, respectively.
High pressure with quiet weather dominates over most of the Mediterranean Sea.
DISCUSSION
... SE Turkey, Syria, Iraq ...
A pronounced cold front moves east along with the main trough axis. Fed by Mediterranean moisture, a tongue with a few hundred J/Kg CAPE is advected far inland. Under 0-3 km shear up to 20 m/s, severe wind gusts are possible in case of linear storm mode (more likely), whereas one or two tornadoes cannot be discounted in case more discrete storms form. Flash floods (or excessive snowfalls in the Turkish mountains) become another risk under strong synoptic and orographic lift. Activity will move east and gradually weaken around and after sunset.
Scattered, probably non-severe postfrontal storms are also still possible off the Syrian coast until the early afternoon.
... Poland ...
A subtle vorticity maximum overspreads the mild and moist air. Its lift and weak diurnal heating steepen the lapse rates enough to allow neutral profiles across the lower troposphere. Low-topped, multicellular convection is possible especially in the 08 to 14 UTC time frame. It will probably struggle to become deep enough for lightning. If it does, isolated severe wind gusts or tornadoes are not ruled out under very strong shear and helicity, but the risk appears too low for a level 1.
... British Isles ...
Wind gusts of 25-30 m/s will become more widespread as the second storm cyclone approaches, but a notable convective contribution is not expected.
