Deep in the southwest of Europe
Deep in southwest Europe , also Spain low or low in front of / over the Iberian Peninsula, is a comparatively rare general weather situation in Europe.
The term “ Tief im Südwest Europa” (TSW) is one of the general weather conditions categories commonly used in Austrian meteorology.
Low pressure areas over south-western Europe are comparatively rare forms of Atlantic lows with a mid-Atlantic (subtropical) influence, which cause unusual weather phenomena. The west wind drift that drives Atlantic lows over Europe is usually much further north, as the Azores high pushes them past at around 45–60 ° latitude . Lows off the Iberian Peninsula occur only when the Azores high is very weak, abnormally far to the west, or at all in the far north ( high-over-low position ). Since the north latitude of the west wind drift fluctuates with the position of the sun , this location of the action center is typical for the winter half-year .
A low in south-west Europe pumps warm air masses over Europe on its front, which is why foehn-like south-westerly high-altitude currents or real (north) foehn form over the Alps . At the same time, the dust pollution of the atmosphere increases, and in isolated cases Saharan dust phenomena can occur. On the Iberian Peninsula , meanwhile, there is bad weather, often with intense rain or snow, at the rear, polar cold air can flow deep south, up to cold waves and snowfall on the western African north coast (Algeria, Morocco; Atlas Mountains ).
Depths arriving from the Atlantic or forming off the Spanish-Portuguese coast converge on the Pyrenees and, if they do not disintegrate, usually take two routes:
- North over the Bay of Biscay , then one also speaks of low above the Biscay . These hit land in France and can either pass north of the Alps ( Central Europe Low ) or immigrate south-east into the Mediterranean
- South past over northern Spain ( Spanientief i. E. S.), and then into the Mediterranean
In the latter two cases, one speaks as a result of depression over the western Mediterranean (TWM, Genoa depth ) . These lows can lead to heavy rain on the Italian peninsula and in the southern Alpine region.
Individual evidence
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↑ a b c Example low Monika December 2010: A mighty Atlantic low pulls 4th , 5th , 6th in front of the Iberian Peninsula, an accompanying low (Monika) gains 7th on the northwestern tip of Spain and 8th power over the Bay of Biscay, and then pulls quickly along the Alps via Poland on the 9th to the Baltic on the 10th ; explicit TSW weather situation is only on the 8th, before that there was influence of a low over the Baltic States ( liana , weather situation TK ); 6./7. ( Nikolo / Samichlaus ) with a front from the north, but then a warm front from the south, first a lot of snow, then heavy rain (floods in Switzerland), then 7./8. intensive foehn (Bludenz 17.6 ° C, absolute monthly maximum), in the night of 8/9 goes through an "almost textbook-like" cold front; The snowfall line rises in one day from less than 1000 m to 2500 m and back again.
all maps analysis maps , met.fu-berlin.de; Weather conditions and weather cited from monthly review December 2010 , zamg.ac.at and weather archive: December 6, 2010 ( Memento of the original from December 15, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. ff, meteo.srf.ch (with satellite map) -
↑ a b c Example low Yvan March 2011: A low near the British Isles (Xander) on the 12th produces a marginal low in its extensive cold front 13th / 14th , the 15th being a mighty low pressure complex over Spain, and consequently from the west Mediterranean ( 16th ) moves against the Alps ( 17th ); explicit TSW weather situation is only on the 15th, on the 14th a retreating continental low still dominates ; 14./15. There is sunshine in the Alpine region "apart from the immediate southern reservoir regions, and it is extremely mild (up to 21 °, 1st day over 20 ° of the year), heavy rain falls in the Carnic Alps and the Karawanken", 16. – 19. “Intense precipitation, the snow line sinks into many valleys; in Bregenz almost all of the monthly precipitation falls within 24 hours with around 90 mm, in the Maggia valley 60–80 cm fresh snow ”. all maps analysis maps , met.fu-berlin.de; Weather conditions and weather cited from monthly review March 2011 , zamg.ac.at and weather archive: March 13, 2011 ( Memento of the original from December 15, 2013 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. ff, meteo.srf.ch (with satellite map)
- ↑ so also hurricane Lothar December 1999
- ↑ flyway Va according Bebber ; so also hurricane Klaus January 2009
High above Western and Central Europe (H) • Intermediate high (h) • Zonal high pressure bridge (Hz) • High with core over Fennoscandia (HF) • High with core over Eastern Europe (HE) • North (N) • North-west (NW) • West (W) • Southwest facing (SW) • South facing (S) • Gradient weak position (G) • Deep south of the Alps (TS) • Deep above the western Mediterranean (TwM) • Deep in Southwest Europe (TSW) • Deep near the British Isles (TB) • Meridional low pressure channel (TR) • Continental low (Tk) • Low on the Adriatic - Poland train route (Vb)