Storm Forecast
Valid: Mon 02 Nov 2009 06:00 to Tue 03 Nov 2009 06:00 UTC
Issued: Sun 01 Nov 2009 21:35
Forecaster: DAHL

No threat levels have been issued.

SYNOPSIS

An intense upper trough will rapidly be moving across the Alpine regions into the Ionian-Sea region during the period. Its progression into the N Mediterranean will be accompanied by rather intense cyclogenesis over the Gulf of Genoa, moving into the central Adriatic. Otherwise, an extensive SFC low complex persists over the N Atlantic and the North Sea, with an equally large SFC high covering eastern parts of Europe and Russia.


DISCUSSION

... central Mediterranean ...

Weak and rather shallow instability is expected to develop along and ahead of the cold front of the developing N Mediterranean SFC low. It seems that an appreciable chance of lightning will not develop until the system reaches the Ionian region late Monday night / early Tuesday morning. Deep shear is simulated to weaken in the region of deepening CAPE, so it does not seem that much of a severe weather threat exists. However, there may temporarily be enough shear marginally supportive of isolated severe evolution, possibly materializing as linear segments or low-topped supercells. Main threat will likely be severe wind gusts, and possibly a tornado or two along the coastal regions where LLS should be enhanced. However, allover probabilities are too low for a LVL1 area.

... France ...

In the thermal-trough region over France, some instability is expected during the first half of the day. Over S France, shear will be quite intense (30 m/s in the lowest 6 km), so that some threat of at least brief linear organization and storm-scale rotation exists. This suggests that an isolated severe wind gusts and / or tornado or two cannot be ruled out. However, given the small time window and an allover marginal setup, it seems that a LVL one is not necessary.