Elk gekleurd gebied op de kaart heeft een eigen risiconiveau. Hieronder zie je per gebied waarvoor het niveau is afgegeven.
Niveau 2
Matige kans
Oost-Duitsland, West-Polen
In de middag en avond kunnen zware onweersbuien ontstaan met kans op zware windstoten en geïsoleerde tornado's. De grootste kans op tornado's is in het noordoosten van Duitsland.
Zware windstoten
Tornado's
Niveau 1
Kleine kans
Baltische Staten, Wit-Rusland
Overdag is er een risico op geïsoleerde tornado's in de Baltische Staten en Wit-Rusland. De windschering is zwakker, maar lage wolkenbasis en significante heliciteit verhogen het risico.
Tornado's
Niveau 1
NL
Kleine kans
Oost-Duitsland, West-Polen
In de middag en avond kunnen zware onweersbuien ontstaan met kans op zware windstoten en geïsoleerde tornado's. Er is ook een risico op zware regenval, vooral in het westen van het gebied.
Zware windstoten
Tornado's
Extreme neerslag
Niveau 1
Kleine kans
Denemarken, Zuidelijke Oostzee
In de middag en avond kunnen zware onweersbuien ontstaan met kans op zware windstoten, hagel en geïsoleerde tornado's. De grootste kans op tornado's is aan de kust.
Zware windstoten
Grote hagel
Tornado's
Niveau 1
Kleine kans
Zuidwest-Rusland
In de middag en avond kunnen onweersbuien ontstaan met kans op hagel en zware windstoten. De buien kunnen lokaal intens zijn.
Grote hagel
Zware windstoten
Niveau 1
NL
Kleine kans
Noord-Duitsland, Denemarken
Zware regenval en sterke tot zware windstoten worden verwacht, vooral in Noord-Duitsland en Denemarken. Er is ook een geïsoleerd risico op tornado's, vooral bij convectieve elementen die afwijken van de hoofdshearvector. De grootste dreiging is in de namiddag en avond.
Extreme neerslag
Zware windstoten
Tornado's
Onweer
50% kans op onweer
Noord-Finland, Noordwest-Rusland
Onweer
50% kans op onweer
Letland, Estland, Rusland
Onweer
50% kans op onweer
Noord-Duitsland, Denemarken
Onweer
50% kans op onweer
Zuid-Rusland, Noord-Kaukasus
Onweer
50% kans op onweer
West-Turkije
Onweer
50% kans op onweer
Griekenland
Onweer
50% kans op onweer
Zuid-Rusland, Noord-Kaukasus
Onweer
50% kans op onweer
Wit-Rusland
Onweer
50% kans op onweer
Finland, Rusland
Onweer
50% kans op onweer
Denemarken, Zuid-Zweden
Onweer
50% kans op onweer
Oost-Duitsland, West-Polen
Onweer
50% kans op onweer
Portugal
Onweer
15% kans op onweer
Portugal, Spanje
Onweer
NL
15% kans op onweer
Polen, Wit-Rusland, Baltische Staten
Onweer
15% kans op onweer
Malta, Zuid-Italië
Onweer
15% kans op onweer
Noordwest-Spanje, Noord-Portugal
Onweer
15% kans op onweer
Noord-Finland, Noordwest-Rusland
Onweer
NL
15% kans op onweer
Oekraïne, Polen, Slowakije, Hongarije
Deze samenvatting is automatisch gegenereerd op basis van de originele ESTOFEX-outlook en kan afwijken van de bron. Raadpleeg de volledige outlook voor het volledige beeld.
A level 1 was issued from Belgium to Poland and Denmark for a mix of heavy rain, strong to severe gusts and an isolated tornado risk.
A level 1 was issued for part of the Baltic States to Belarus mainly for an isolated tornado risk.
SYNOPSIS and DISCUSSION
A still highly uncertain risk of organized convection exists with a passing and gradually evolving wave, which crosses N Germany/N Poland E during the daytime hours, before deepening into a closed vortex over the Baltic States during the night.
What bears watching is the highly anomalous nature of the parameter space, which converges along the wave's path.
Impressive energy transfer/zonal wave flux occurs over N Europe into a Scandinavian trough with anomalous low heights from Scandinavia to Scotland. This energy transfer meets an anomalous intense subtropical ridge, which runs from Spain to S France. In-between, an impressive 2-3 sigma deviation of mid/upper level winds is forecast with jet core winds in excess of 140 kt at H25/3. This deep/polward sloped frontal zone also offers H7 winds in excess of 50 kt, which creates anomalies in excess of 2 sigma to the background climatology.
This dynamic regime meets an IVT maximum in excess of 1300 kg/m/s, which highlights not only very effective moisture advection, but also an impressive magnitude of moisture with TPWs in the 35-45 mm range, spreading over Benelux/N Germany E. In fact, this moisture plume could be accompanied by a diabatic Rossby wave (DRW), which then turns into our progressive wave.
Right now the only missing ingredient seems to be enough upper dynamics in form of a sharp IPV maximum. The shown scenario favors a broad and gradually sharpening trough during the forecast period, sparking BL vortex development late in this forecast over N Poland into the Baltic States. A more rapid positive PV imprint in the BL is still possible however and is shown in some GEFS/IFS members. This evolving depression seems to be a complex interaction of a lee cyclone E of Norway with the leftover of the DRW. IFS-ENS also reveals an ongoing spread with a broad member cloud of MSLP minima in the 1000-1010 hPa range at 12Z over N Germany to the S Baltic Sea.
Details dictate how much instability build-up will occur along the wave's path. Meager mid-level lapse rates occur (due to the tropical background of this potential DRW and tropospheric airmass), but robust moisture advection increases probabilities for at least skinny CAPE profiles.
We most likely see some heavy rain issues along the wave's tip, as 55kt at H85 feed anomalous moisture into elevated (probably non-thundery) convection. This risk increases if we see a passing wave and is currently maximized somewhere over N Germany in NWP guidance.
Otherwise, the gust risk over Belgium/the Netherlands to Germany will be the main issue, also highlighted by the EFI gust forecast with values in the 0.9-1 range, including a positive SOT over N Germany. Any convective component could induce a severe gust threat especially for convective elements, which deviate more from the 20-30 m/s 3km shear vector, which is out from the west. This is possible N of the wave's tip with cooling mid-levels but also if we get a closed vortex/warm sector, which bends the cold front more SW-NE. A broken LEWP along the leading edge of the wave is forecast right now with strong to severe gust. Line segments/breaks will be prone to isolated tornado activity in extreme shear, as point source soundings show skinny CAPE with 22 m/s LL shear, 30 m/s 0-3km shear and SRH 1 and 3km in excess of 350-400 m2/s2. If we get only somewhat better CAPE in this shear setup, we would also need to add an isolated strong tornado risk.
Right now we just added a broad level 1 area to highlight a general augmented risk. Major discrepancies of the wave's path and development stage could decrease overall severe risk but also push it locally into a significant stage, especially in case of a more aggressive LL vortex spin up (which seems less likely right now due to the mentioned delayed upper IPV approach and which is supported by a current weakening trend f.ex. in latest ICON runs). In the end, we could also see a rather inactive wave passage with a severe corridor to its N, covering N Germany into Denmark.
This event bears close monitoring in further runs and a regional upgrade/downgrade will be possible.
Another level 1 was added for the Baltic States into Belarus for a lead wave, which affects this area during the daytime hours. Shear is weaker, but low LCLs and some noteworthy SRH induce an isolated tornado risk.
Portugal and SW Spain could see a nocturnal risk of a few elevated thunderstorms in response to an approaching upper trough. Some hail would be the main issue next to a few gusts. Right now, EPS data only reveals some signals in EPS maxima, so not much confidence for CI right now (although NWP guidance has problems with elevated CI and overall pattern could favor more aggressive CI during the night).
TUSCHY / ESTOFEX
