Re: Seg. Especial Chuva e Trovoadas de 21 a 25 Fevereiro 2008
Mais um alerta
Storm Forecast
Valid: Sun 24 Feb 2008 06:00 to Mon 25 Feb 2008 06:00 UTC
Issued: Sat 23 Feb 2008 20:01
Forecaster: TUSCHY
SYNOPSIS
A fragile omega pattern over the Mediterranean has established but is in evidence in upper-level streamline maps. Framed by two troughs one over SW Europe and the other over SE Europe, ridging is present over Italy and Germany with unseasonably warm conditions. A belt of strong westerlies covers most parts of N-Europe but only one depression is of interest . This feature moves onshore over N-Norway with a low-end thunderstorm risk.
DISCUSSION
.... Parts of Portugal and Spain ....
Downstream of a decaying upper-level trough just west of Portugal winds at all levels turn on southerly directions during the morning hours, but veer somewhat in the mid-levels during the early afternoon hours onwards. Main reason for this wind shift is the highly positive tilt of upper-level trough, centered over Portugal during the afternoon hours. Main concern for an isolated severe weather risk arises along the Strait of Gibraltar and north / northeastwards. Strongest warming / cap looks like to be displaced to the east and despite limited diabatic heating, surface temperatures in this area should soar into the mid-tens. In addition, current dewpoints are already good and after the end of easterly winds ( e.g. Levante-event in the Strait of Gibraltar ) during the morning hours an onset of southerly winds will push another surge of moist air northwards, increasing dewpoints 1-2°C ( e.g. Granada sounding ). Forecast soundings in this area hint on deep convection, steep LL lapse rates and strong veering at lowest levels. Despite the already uncapped airmass a modest mid-level speed max approaches from the west, placing the area of interest under the left-exit region.
Overall degree of shear is not impressive, but low or slightly lifted LCLs and combination of veering and maximized 0-3km instability release could be enough for an isolated funnel / short-lived tornado and large hail report. We want to highlight this area in such a broad general thunderstorm area and increased probabilities to a low-end level-1. Severe weather / Thunderstorms will diminish after sunset.
Regarding thunderstorm coverage, the main activity will be confined to S-Portugal and extreme SW-Spain. There will be a flash flood risk as steering flow is weak, airmass quite moist and a persistent 15m/s LLJ points to the coast of Portugal for a prolonged period.
isto no Verão vai ser bem melhor ainda andam muitos anticiclones perdidos quando forem todos para cima dos Açores é que vai ser...adoro estas cartas.
é uma questão de tempo para que o clima dê a volta e o AA nos deixe de perseguir 
acho que amanhã de manhã vai haver festa da grossa.