Unusually stable and warm pattern persisted over much of Europe during the last weeks, with much above average temperatures and much below average precipitation. This is slowly becoming a serious threat for the agricultures as drought is just around the corner if we don’t receive some rain soon. This year’s water balance (the difference between total rainfall and total evapotranspiration – pETO) across Slovenia and southern Alpine region is already between -50 and -100mm and it is just getting worse with expected sunny/warm conditions in the next two weeks. Such sunny/windy days like this week have daily pETO around 5mm, so one can imagine how fast this is worsening.
With persisting ridging over Europe there is also a lack of convective activity this year where no serious activity have been seen this season yet. However, there were only two cold frontal activities where the last front about a week ago was quite interesting. Please refer to the previous blog post for some photos or click here to see images in my gallery: First lightning strikes of the season (Prosecco, Italy) – 12/04/2011.
As mentioned earlier, stable weather is on schedule for the following week as a large omega-like block pattern persists over S-CNTRL Europe. However, there is some activity expected in SW corner of Europe where an upper low is wobbling west of Iberia. Here is the forecast for today I made at ESTOFEX…
At ESTOFEX, a level 1 was issued for mostly Alpine region, read more details below:
Valid: Tue 19 Apr 2011 06:00 to Wed 20 Apr 2011 06:00 UTC
Issued: Mon 18 Apr 2011 19:56
No threat levels have been issued.
SYNOPSIS / DISCUSSION
The dominant feature on Tuesday is the moderate ridging over much of south central Europe. On its edges, two upper lows will be the focus for convective activity. One remaining quasi stationary over eastern Aegean sea / western Turkey where only marginal diurnal activity is expected in non-sheared environment.
Another developing potent upper low NW of Iberia and moving southwards will be the main focus for convection over Iberian peninsula. A surface cold front will set west of peninsula. SW flow ahead of the this cold front will continue advecting warm airmass northwards across the peninsula, resulting in unstable airmass. Several hundreds of MLCAPE will result but given the rather limited deep layer shear, severe storms are unlikely. A lack of large scale ascent will also limit the activity. But however, the complex topography should trigger convection over parts of Spain and Portugal as a result of strong daytime heating. Slightly better shear is located over southern Iberia where the strongest cells could become briefly organized with threat for some marginally large hail but not reaching severe criteria. Activity will be mostly diurnal driven and should diminish after sunset.
Source: ESTOFEX outlook from April 19th 06z until April 20th 06z 2011
Stay tuned for future updates!