Avisos, Alertas e Previsões oficiais - Setembro 2014

david 6

Super Célula
Registo
22 Jan 2013
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8,883
Local
Fajarda - Coruche(57m)
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According to both satellite image loops and NWP output, cut-off low, centered over the Baltic Sea as of Wednesday 06 UTC, will continue moving southwards, its base reaching N Italy by Thursday morning. This cut-off will move on the forward flank of the ridge stretching over British Isles. A trough is also to forecast to affect W Iberia during the day. Most of Southeastern and Eastern Europe will remain in lower geopotentials.
 
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Duarte Sousa

Staff
Registo
8 Mar 2011
Mensagens
5,994
Local
Loures
Storm Forecast
Valid: Fri 12 Sep 2014 06:00 to Sat 13 Sep 2014 06:00 UTC
Issued: Thu 11 Sep 2014 16:59
Forecaster: TUSCHY
A level 1 was issued for parts of Portugal and NW Spain mainly for an isolated large hail event and excessive rain.

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DISCUSSION

... Portugal and NW Spain ...

Subtropical air advects onshore but weak mid-layer lapse rates keep MLCAPE in the 500-800 J/kg range. Until sunset no distinct lift mechanism is seen in model fields but the left exit of a subtropical jet streak and weak upper divergence support a few thunderstorms over N-Portugal and extreme NW Spain. DLS oscillates around 15 m/s, so a few large hail events and heavy rain will be the main risk.

During the night, the mid/upper flow turns more cyclonic ahead of a strengthening disturbance, which approaches the W-Iberian Peninsula during the end of the forecast. The flow becomes more diffluent and weakens, so DLS drops to 10-15 m/s. However, N-ward spreading EML atop the marine air mass pushes onshore CAPE to 1 kJ/kg and offshore CAPE to values in excess of 1.5 kJ/kg. A few storms continue to fire and large hail/heavy rain remain the main hazard.

http://estofex.org/
 
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rubenpires93

Cumulus
Registo
13 Abr 2010
Mensagens
251
Local
Castelo Branco (400)
Estofex Forecast 14/09:

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Storm Forecast
Valid: Sun 14 Sep 2014 06:00 to Mon 15 Sep 2014 06:00 UTC
Issued: Sun 14 Sep 2014 08:05
Forecaster: VAN DER VELDE

A level 2 was issued for northeastern Spain mainly for large hail.

A level 1 was issued for northern Spain for large hail and severe wind gusts.

SYNOPSIS

An extensive blocking high pressure system is situated between Ireland and Russia, centered over Scandinavia. An Atlantic low lies in front of Portugal, with a thermal low over the Iberian Peninsula. Three upper cut-off lows are found near Denmark, Croatia and Russia.

...Iberian Peninsula...

Very moist Mediterranean air (13-14 g/kg) accumulates along the east coast. With diurnal heating the thermal low activates and moist air gets advected inland mainly through the Ebro Valley. In mid and upper levels a cold front passes from the southwest, crossing northeastern Spain during afternoon and evening, helping destabilize the mid levels where soundings indicated some inversions. A SW-NE oriented PV gradient is advected parallel to the flow which can add upward destabilizing motions. MLCAPE will range from 1000 to 1500, maybe locally up to 2000 J/kg. Vertical wind shear is enhanced to double the values present last week: around 20 m/s 0-6 km vectors and 30 m/s BL-8 km vectors. These should support supercells as the main mode, but low-level end of the hodographs in GFS do not show much curvature, in fact 0-1 km shear is weak and streamwise vorticity (storm-relative helicity) remains below 100 m²/s². Some split-cell behaviour will likely be observed. The storms will easily produce large to very large hail (5 cm or larger), helped by broad updrafts with cloud bases at 1500-2500m. Isolated severe wind gusts also are likely.
As CAPE should decrease toward the north of Spain, but low-level hodographs improve, the level 2 spans also this area where supercellular storms can occur. To the east, parts of Catalonia will remain capped. Northern Aragon may see an MCS developing during evening into the night with continued chances of large hail and severe wind gusts.
 

PedroMAR

Cumulus
Registo
13 Nov 2011
Mensagens
214
Local
S. Miguel de Machede, Évora
_____________________________________________________________________
MINISTÉRIO DA AGRICULTURA E DO MAR
INSTITUTO PORTUGUÊS DO MAR E DA ATMOSFERA,I.P.
Departamento de Meteorologia e Geofísica
Divisão de Previsão Meteorológica, Vigilância e Serviços Espaciais ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
Aviso Meteorológico - CONTINENTE
_____________________________________________________________________
COMUNICADO Nº. 192/2014
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Devido a uma depressão centrada a oeste da Península, com um sistema frontal associado, em fase de oclusão emite-se:
__________________
- AVISOS AMARELO -
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ »»» PRECIPITAÇÃO ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ Nos distritos de VIANA DO CASTELO, BRAGA, PORTO, VILA REAL, BRAGANÇA
e VISEU, GUARDA, CASTELO BRANCO, AVEIRO, COIMBRA
e LEIRIA, LISBOA, SETÚBAL, SANTARÉM, PORTALEGRE
e ÉVORA, BEJA e FARO
Desde as 19:00UTC de 15.09.14
até as 21:00UTC de 15.09.14
Aguaceiros, por vezes fortes e condições favoráveis à ocorrência de trovoada.

Nos distritos de LEIRIA, LISBOA, SETÚBAL, SANTARÉM, BEJA e FARO Desde as 03:00UTC de 16.09.14
até as 00:00UTC de 17.09.14
Aguaceiros, por vezes forte e condições favoráveis à ocorrência de trovoada.

Nos distritos de CASTELO BRANCO, COIMBRA, PORTALEGRE e ÉVORA Desde as 06:00UTC de 16.09.14
até as 03:00UTC de 17.09.14
Aguaceiros, por vezes forte e condições favoráveis à ocorrência de trovoada.

Nos distritos de VIANA DO CASTELO, BRAGA, PORTO, VISEU, GUARDA
e AVEIRO
Desde as 08:00UTC de 16.09.14
até as 03:00UTC de 17.09.14
Aguaceiros, por vezes forte e condições favoráveis à ocorrência de trovoada.

Nos distritos de VILA REAL e BRAGANÇA
Desde as 12:00UTC de 16.09.14
até as 00:00UTC de 17.09.14
Aguaceiros, por vezes forte e condições favoráveis à ocorrência de trovoada.

»»» VENTO - RAJADA MÁXIMA
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
Nos distritos de SETÚBAL, BEJA e FARO
Desde as 06:00UTC de 16.09.14
até as 21:00UTC de 16.09.14
No LITORAL: Vento forte com rajadas da ordem dos 70 km/h.

Nos distritos de VIANA DO CASTELO, BRAGA, PORTO, VILA REAL, BRAGANÇA
e VISEU, GUARDA, CASTELO BRANCO, AVEIRO, COIMBRA
e LEIRIA e PORTALEGRE
Desde as 03:00UTC de 16.09.14
até as 06:00UTC de 17.09.14
Nas TERRAS ALTAS: Vento forte com rajadas da ordem dos 90 km/h.

Nos distritos de LISBOA, SETÚBAL, BEJA e FARO Desde as 03:00UTC de 16.09.14
até as 00:00UTC de 17.09.14
Nas TERRAS ALTAS: Vento forte com rajadas da ordem dos 80 km/h.

Nos distritos de VIANA DO CASTELO, BRAGA, PORTO, AVEIRO, COIMBRA
e LEIRIA e LISBOA
Desde as 06:00UTC de 16.09.14
até as 06:00UTC de 17.09.14
No LITORAL: Vento forte com rajadas da ordem dos 70 km/h.


Lisboa, 15 de Setembro de 2014 às 18:45 UTC O Meteorologista: Joana Sanches
 

rubenpires93

Cumulus
Registo
13 Abr 2010
Mensagens
251
Local
Castelo Branco (400)
Upgrade dos avisos por parte do IPMA:
upyERby.png


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Honestamente, acho que vêm um bocado tarde.

Tal como tinha dito, tal vem nos mencionado nos avisos ..
Sim de facto este update para laranja deveria ser feito quanto muito ao início da manhã .. Mas prontos, prefiro que o IPMA os emita correctamente e mais tarde do que não o fazer ou emitir em excesso ou por escassez!
(Eles irão ser sempre criticados por todos e com razão, mas já sabemos com o que contactos com aquele organismo português mas há que mencionar que às vezes as criticas são demasiado exageradas por parte de muitos membros e aficionados quer aqui como em outros espaços e até mesmo o leigo do povo refere isto..)

Independentemente se quarta é mais forte do que amanhã, sugiro antes que sigam assim: "Nas próximas 48h/72h as condições meteorológicas sofreram agravamento e estão previstas chuvas/aguaceiros moderados/forte e granizo; ventos moderados/fortes; ocorrência de trovoada; perigo de inundações rápidas; chances (ainda que baixas) de fenómenos localizados de vento excessivo com downburst e mais prováveis a ocorrer junto da costa litoral, vento moderado a forte nas terras altas inclusivé."

3ª 16/09 - Vento será mais forte que 4ª 17/09
4ª 17/09 - A chuva/aguaceiros terá mais acumulados que 3ª 16/09

(Deverá ser por aqui que estará as intensidades)
 
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Duarte Sousa

Staff
Registo
8 Mar 2011
Mensagens
5,994
Local
Loures
Storm Forecast
Valid: Wed 17 Sep 2014 06:00 to Thu 18 Sep 2014 06:00 UTC
Issued: Tue 16 Sep 2014 18:25
Forecaster: BEYER

A level 1 was issued for Portugal and Western Spain mainly for large hail and severe wind gusts.

zR45eGQ.png


Portugal and Western Spain...

...with a southwesterly to southerly flow BL humidity is advected into the western parts of the Iberian Peninsula. It is highest near the coast with mixing ratios that increase until around 12 g/kg throughout the day. The values are smaller going more inland. Rather cool mid-level temperatures in combination with diurnal heating lead to a steepening of the lapse rates. Thus CAPE values of 500 to 1000 J/kg should develop in the afternoon hours with the highest values near the coastline.

Deep layer shear is about 15 m/s, in the late afternoon also values of up to 20 m/s can be found. Therefore better organized convection is possible that can bring strong to severe wind gusts as well as large hail. Since ppws are only between 25 to locally 30 mm and storm motion is forecasted to be quite high (W500: 30 to 40 kn) the excessive rain threat is limited. Only along the coast with several storms moving over the same area a local event cannot fully be ruled out.

First storms should occur even in the forenoon hours. Highest activity is forecasted in the noon and afternoon hours when an IPV maximum enters the region of interest and provides the needed lift ingredient. In the afternoon this maximum travels northward. In combination with the diurnal cooling of the BL, storm activity is forecasted to decrease.
 

Miguel96

Cumulonimbus
Registo
13 Fev 2011
Mensagens
3,128
Local
Espinho, distrito de Aveiro
Aviso válido para o dia 17/09/2014

20140916_day1.png


A SLGT risk has been issued for surrounding areas of HIGH/MDT risk including the N-W Iberia, NW Mediterranean, S France and NW Italy with threat for excessive rainfall and lesser extent for severe winds, large hail and tornado threat.

Em português:

Um risco slight (leve) foi emitido para as áreas de alto /moderado risco incluindo o NW da Ibéria, NW do Mediterrâneo, Sul de França e NW de Itália com possibilidade de ocorrência de grandes quantidades de chuva e em menor grau rajadas severas de vento, queda granizo e possibilidade de tornados.