Seguimento Europa - 2008

Chasing Thunder

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Grande Célula que vai neste momento para o sul de Itália:shocking:



E Segundo o meteoalarm o sul de itália e a ilha de Sardegna estão em alerta laranja devido ás trovoadas e á percipitação forte:eek:.

 


Chasing Thunder

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Para amanhã preve-se que seja um dia de muito vento na inglaterra:(, porque está uma depressão a norte da islandia e que a sua pressão no centro é de 955hpa:surprise::eek:

 

Chasing Thunder

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E aqui fica o Aviso do Estofex para amanhã dia 23 de Outubro na Europa.



SYNOPSIS

Strong cyclogenesis goes on over the Iceland area. An intense surface low will develop over Iceland, while the cold front will cross the British Isles during the period. East of the cold front, strong warm air advection will be present from the Atlantic Ocean to British Isles and further to the North Sea west of Norway. At higher levels, a strong jet streak will curve around the northern Atlantic trough, and geopotential rises at its anticyclonic flank from Bay of Biscay to Germany and southern Scandinavia, where upper ridge moves eastward during the period. Further east, upper trough cuts of over Iberian Peninsula and moves southward, while remaining sharp trough weakens and accelerates over Baltic Sea region. Another trough moves eastward over Turkey.

DISCUSSION

British Isles, North Sea region

A tongue of moist and quite warm air mass that will likely be characterized by neutral lapse rates is advected north-eastwards ahead of the cold front with strong south-westerly winds. Thermodynamic profiles in the warm sector will be characterized by strong 0-1 km SRH in the range of 300 m²/s² underneath a 30 m/s 850hPa jet from British Isles to western Norway. As the axis of the strong mid-level jet remains to the north-west of the cold front, deep instability is not expected along the cold front. However, strong mid-level winds will spread across the warm sector from British Isles to Norway as indicated by latest models, where ageostrophic advection of low-level moisture will likely help to develop instability in the moist air mass. Along the cold front, low-level convergence and lift is forecast, and a shallow convective line is expected. Given strong vertical wind shear, bowing segments will likely develop, with a chance of severe wind gusts. Mesoscale vortices between such bowing segments may be favourable places for isolated tornadoes. Threat is forecast to be relatively low. Lightning is forecast to occur isolated given warm equilibrium level over most places. Best potential seems to exist near Norway, where nose of warm air mass will be quite unstable underneath low geopotential and quite cold mid-levels as indicated by latest model output.

In the wake of the front, maritime air mass will likely be unstable as cold mid-level air mass in the range of the trough centre spreads into northern British Isles. Thunderstorms that form will also have a potential of producing severe wind gusts and isolated tornadoes given strong low-level vertical wind shear.

South-western Mediterranean

An upper cut-off trough moves southward over Iberian Peninsula. A strong mid-level jet streak curving around the troughs base is forecast to spread into west Mediterranean Sea late in the period. At lower levels, easterly winds will advect quite rich low-level moisture. As the upper jet streak approaches, mid-level height falls are likely from northern Morocco to northern Algeria and south-western Mediterranean, and instability is forecast to form. QG forcing and some low-level convergence in the range of the African coast is expected to be sufficient for initiation, and thunderstorms are forecast to develop and spread northwards into Balearic Islands. Given strong vertical wind shear, organized convection is forecast, capable of producing isolated large hail and severe wind gusts. Although low-level vertical wind shear and buoyancy are not too strong, isolated tornadoes are not ruled out.

South Mediterranean Sea

Southerly winds are forecast over the Mediterranean Sea to the south of a convergence line over central Mediterranean dividing quite dry easterly flow to the north from rich low-level moisture. Thunderstorms are forecast to go on in this region. As low-level buoyancy is rather strong and vertical wind shear will be weak, some waterspouts are forecast.
 

Mário Barros

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Itália: Tempestade faz 4 mortos na Sardenha

Quatro pessoas morreram hoje na Sardenha, afogadas na sua casa ou em viaturas arrastadas por torrentes de água e lama, na sequência da violenta tempestade que se abateu sobre esta ilha a ocidente de Itália, revelaram os bombeiros.
A tempestade, que foi acompanhada de chuvas diluvianas, atingiu a capital regional, Cagliari, e a sua região, no Sul da ilha, às primeiras horas do dia.

As vítimas são uma mulher de 85 anos, afogada na cave da sua casa invadida pelas águas, uma outra mulher encontrada morta perto de um campo de ténis e outras duas pessoas que circulavam em dois automóveis diferentes, levados por uma torrente de água.

Em Capoterra, a cerca de 15 quilómetros de Cagliari, um milhar de habitantes ficou isolado pelas águas durante várias horas e os bombeiros tiveram de esvaziar preventivamente uma barragem que ameaçava ceder.

As estradas e as linhas de electricidade sofreram danos na região de Cagliari e as autoridades recorreram a helicópteros e viaturas do exército para retirar os habitantes das áreas inundadas.

O mau tempo afectou também as ligações aéreas entre Cagliari e a Península.

Ena pá :surprise::surprise:
 

Chasing Thunder

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Para hoje em Inglaterra são esperadas rajádas de vento que atingem os 120 kmh:eek:

Só por curiosidade em Capel Curig já houve uma rajáda de 105kmh
 

Mário Barros

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Para hoje em Inglaterra são esperadas rajádas de vento que atingem os 120 kmh:eek:

Só por curiosidade em Capel Curig já houve uma rajáda de 105kmh

Nada, de anormal para o tipico inglês, aliás seria mais anormal não terem situações dessas.
 

Chasing Thunder

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Aviso do estofex para amanhã dia 24 de Outobro na Europa



SYNOPSIS

Major large-scale modifications of the streamline pattern are underway with a transition from a more zonal to a strongly blocked pattern from North-America to Europe during the upcoming week. Strong upper trough, currently situated over extreme NE-North-America/SE-Canada shifts eastwards during the following 2-3 days, gaining strength over the N-Atlantic, while increasing its amplitude. Its span of life won't be remarkable high, but still it is worthwhile to watch its evolution as its finaly placement/strength and duration of decay will be crucial for the exact evolution over Europe next week.

Over the NE Atlantic, 12Z-CMC analysis has a strong and very well structured cold-core low over Iceland (04018 has the tropopause well below 5km) and numerous smaller-scale depressions, rotating around the main vortex. Intense CAA upstream of this vortex is underway but as SSTs gradually increase to 9-10°C S/SE of Iceland, rapid modification of the lower column of the atmosphere should occur. Not so at mid-levels, where temperatures reach -35 to-40°C at 500hPa S/SE and E of Iceland, so an extensive area will see steep lapse rates with modest instability release between Iceland - Scotland and NW-Europe. Wind field at lower levels increases over this area in response to an intensifying surface depression (EZMWF 941hPa, CMC 10hPa higher, which is in line with GFS) NE of Iceland, so we have to discuss this area regarding organized thunderstorm potential.

Finally, another depression forms during the night hours west of Ireland, moving rapidly to the east/northeast, producing an intense wind field, which could affect the extreme NW part of the forecast area. As seen in the past few weeks, the position and strength of the strong high pressure area over the Azores assists upper troughs/cut-off lows to dig very far to the south, such as tomorrow, when a weakening upper trough will be placed over far NW-Africa. This feature will be well to the south of our area of responsibility, but embedded in this channel of low geopotential heights, a small cold-core low drops southwards over Spain, resulting in unsettled conditions over SW-Europe. The rest of Europe has high surface pressure with numerous upper disturbances over SE/E-Europe...the overall set-up is alike the Fri 10 Oct 2008 one.

DISCUSSION

... NW/N-Ireland (03Z onwards) ...

Despite the agreement of the occurrence of a developing depression west of Ireland during the night hours, the rate of intensification remains uncertain. Models like the EZWMF, CMC and GFS all show a very tight baroclinic zone which evolves over the NE-Atlantic and also mid-/upper wind field gains strength, so regarding dynamic affects, conditions for rapid cyclogenesis are fine. The main focus for thunderstorms will be the SE-quadrant of the depression, as strong dry slot works its way to the east, overspreading a warm/moist warm sector, while an intense UVV field overspreads the area of interest from the WSW. Some potential instability could be released, resulting in showers/isolated thunderstorms. Wind field in this area is breathtaking with readings of 40m/s at 850hPa and depending on the intensification rate and the timing of the dry slot, the evolution of a sting jet looks possible, which could even augment wind speeds. For now, a level-1 was issued as most of the activity will stay out of the forecast area until 06Z. A thunder area may be needed, if convective activity will be stronger than anticipated.

... NW-Europe...

The environmental condition was already described in the synopsis. In the aftermath of the active cold front, which crossed the area the night before, strong CAA will be on its way to the east. The airmass is moist and global models show various convergence zones / small-scale vortices, which are embedded in this CAA-regime. Both, parcel layer depth and LL convergence signals are exceptionally strong for this area, so combined with modest SBCAPE and very cold mid-/upper levels, deep convection will be a distinct possibility. Current thinking is that main shower/thunderstorm activity will be confined to the passages of those convergence zones and 20-30m/s winds at 850hPa could result in widespread strong to severe wind gusts. Another focus for enhanced convective activity will be the potential evolution of polar lows, as pattern will be quite favorable for their development, although there remain some negative points (e.g. large-scale, weak WAA downstream of an eastward racing trough...see next paragraph). Latest IR animation (16Z) already had an area of very cold cloud tops SE of Iceland with a cyclonic loop.

Finally, an eastward shifting trough approaches SW-Norway after 18Z and winds at 850hPa should increase to well above 30m/s (40m/s at 700hPa) , which should also enhance the severe wind gust risk along the coastal areas of Norway. All those features combined should justify a level-1 area for severe-damaging wind gusts and isolated tornadoes as a result of deep convection.


... SW-Mediterranean...

Beneath the weakening upper trough, conditions for thunderstorms remain favorable. Wind shear, strong during the morning to afternoon hours, diminishes betimes, while instability release increases during the night hours, as mid-levels cool down. Quite warm LL temperatures should limit LL CAPE release, but GFS still has a belt of enhanced 0-3km CAPE release just south of the Balearic Islands during the evening and night hours. The expected reports should be mainly large hail during the morning / afternoon hours, while the risk of an isolated tornado should increase during the early evening hours, mainly over the level area.

Despite a gradual weakening trend of the SW-flow over N-Algeria, subsidence/weak foehn effects just N of the coast should prevent thunderstorm evolution.
 

Minho

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Deliciem-se com estas fotos tiraradas hoje em Pallars Sobirà nos Pirenéus Catalães

img39352205854ac3.jpg

(C)Silver @meteored

Reportagem completa
 

nimboestrato

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Entretanto a Islândia,até há um mês atrás florescente economia ,agora com profundas dificuldades de sobrevivência,está a ser afectada por dias de Inverno arrasador: uma profunda depressão a cruzar a ilha.
A sua capital , a sudoeste,estava à meia-noite de hoje com 957 hPa,ventos com rajadas próximas dos 100 Km/h e 1º celsius, com aguaceiros de neve e agua-neve...
Imaginem estas condições cá no burgo...
Claro que a Islândia sobreviverá a estes temporais extremos , uns e outros,
ou não fosse o país do planeta que mais lê e menos vê TV.
 

stormy

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Impressionante a Baixa (937 hPa) a norte da Islândia.

Muitos F3 ou até F4, não atingem tão baixa pressão.
o que é q tornados teem a ver com depressoes????ainda q dissesses q
muitos furacoes nao atingem tao baixa pressao..( nao confundas a escala de saffir-simpson com a de fujita;))