Storm Forecast
Valid: Sun 11 Mar 2012 06:00 to Mon 12 Mar 2012 06:00 UTC
Issued: Sat 10 Mar 2012 21:50
Forecaster: SCHLENCZEK
A level 1 was issued for N and central Norway mainly for damaging wind gusts and tornadoes.
A level 1 was issued for Crete and SW Turkey for excessive precipitaton, severe wind gusts, large hail and tornadoes.
SYNOPSIS
An intense 80 m/s upper jet streak with an embedded shortwave trough further upstream points directly towards C Norway. Between a low pressure system associated with this trough and a high pressure system over the British Isles, a very strong gradient flow with 45 m/s at 700 hPa will establish over Scandinavia.
Another low pressure system is centered over the S-central Mediterranean and will move to the northeast. Strong WAA at lower levels ahead of the low and advection of LL moisture leads to some hundred J/kg CAPE. Severe weather is possible as moderate to strong vertical shear is in place.
DISCUSSION
...N and central Norway...
In the vicintiy of the cold front, some low-end instability is consistently forecast by the past three runs of GFS. Very strong LL shear and deep layer shear as well as strong QG forcing may allow organized linear convection. The main threat will be damaging convective wind gusts but an isolated tornado cannot be ruled out as both SRH and LL shear are very high.
...Aegean Sea, Crete, coastal regions of SW Turkey...
MLCAPE in order of 400 J/kg is created over the S Aegean. The region with instability overlaps well with 20 - 25 m/s deep layer shear. Strong veering is indicated by the model hodographs and revealed by SRH3 in order of 400 - 800 mē/sē. Any convective storm which develops in this environment is likely to evolve into a supercell and may become tornadic. In addition to tornadoes, severe wind gusts and large hail are possible as well. High effective PWAT may also suggest a possibility of excessive convective rainfall.
