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III. WIND & WEATHER IN EUROPE METEOROLOGY & OCEANOGRAPHY January April June October benefit from good wind conditions. Summer conditions are a bit calmer topography enhance north-easterly winds in Galicia – if III. Wind & Weather in Europe along the Southern British and other North Sea and Baltic coastlines. The the Atlantic also builds up a nice swell you can expect hile Northern Europe is indulged with consistent westerlies lion’s share probably hits the Dutch and German Frisian Islands, which very clean conditions. Similarly in Portugal; northerly between 40 and 60°N (the Westerly Wind Zone), Southern just brush the southern margins of these northern highs. Northern France winds prevail west of the Iberian heat low and wherever WEurope is broadly effected by the Subtropical Highs. With and Southern England are also pretty well off due to the English Channel’s these are locally enhanced, spots such as Guincho the changing season, the summer sun slowly migrates from the Tropic of ‘Venturi’ jet-effect. Quite frequently though, low-pressure systems also take or Sagres are busy. Morocco and the Canary Islands Cancer in the Northern Hemisphere a southern route during summertime, are especially blessed during the summer. Both are in max. towards its southern winter retreat September 23rd bringing strong winds to Northern the midst of the pressure gradient of the Subtropical equinox at the Tropic of Capricorn. This shift maximum insolation France and North & Baltic Sea High and the Equatorial Low and are treated with of the global weather machinery at the equator coasts. Winds might be easterly if exceptionally stable north-easterly trade winds. Since June 21st changes the general situation in summer solstice you’re north of a low-pressure core, these strengthen along Morocco‘s coastline and between maximum insolation Europe too, meaning weather at the Tropic but persistent easterlies are rare. the Islands, the wind conditions in Morocco and scenarios tangibly differ north and of Cancer That said, a high over Scandinavia particularly on the Canaries are unarguably supreme south of the Alps and Pyrenees. brings reliable easterlies to the European windspeeds knots < 10 - 15 - 20 - 25 - 30 - 35 - 40 - 45 - 50 - 55 - 60 - 65 > between May and September. Baltic Sea. The Azores High retreats out to the Atlantic Ocean Northern Europe Sun The low-pressure racetrack Southern Europe for winter. In doing so, it also moves a few degrees he prevailing westerlies aerate slips south in wintertime, bending he Azores High extends into the Western Mediterranean during the further south and allows troughs of low-pressure from the Westerly Wind the northern coasts of Europe Christmas trees from the North Sea warm season, and at higher altitude it is even effective above the Zone to bully their way into the Mediterranean. They squeeze in via T December 21st T – from Brittany via the British Isles winter solstice to the Spanish coast. Winter storms Eastern Mediterranean. Throughout this region, nice dry IIIweather #4 - Dietherefore wichtigsten the WindsystemeStrait of Gibraltar, im accelerating Mittelmeer the westerly ‘Poniente’ here. During maximum insolation up to Scandinavia – the whole at the Tropic of Capricorn also bring a nice Atlantic Ocean dominates the summer months. Cold fronts will occasionally disturb the wintertime the Mediterranean also produces its own lows that bring rain year around. They’re created by a swell, although the legendary big- Mediterranean, bringing rain and lightning. pressure difference between a pretty- wave spots are only rideable between Ambient summer winds are relatively weak in the March 21st M B much permanent low ranging from Galicia and Brittany or on the British Western Mediterranean, but its topography provides a few o i r equinox s a T t ra r m a T l r maximum insolation on am Southern Greenland via Ireland up and Irish Atlantic facing coast where pleasant surprises: Framed by mountains on nearly all sides, ta n o V at the equator a n a ta r n d to Norway and the subtropical high- the North Atlantic Drift warms the there are precious few narrow gaps between the massifs a a ra te c van M Libeccio Le a G r r in e pressure system in the region between water to tolerable temperatures. through which the wind must make its passage. Each of g Meltemi a l Change of Seasons Levante al e the Azores and South-West Europe. those funnels acts as a jet to accelerate these local winds, Vendev Poniente e h The intensity of sunshine differs in the Capricorn. Therefore the angle of c e e al These pressure zones predominantly pring and autumn provide the also called ‘venturi’ or ‘gap winds’. If the approaching v g e re Northern and Southern Hemispheres. incoming solar radiation differs at L G co concentrate around Iceland (Icelandic best mix of conditions. Powerful air-masses manage to pass the mountains blocking their roc That’s because the Earth’s axis is any given point across the Earth’s S Sci Scirocco Sc iro Low) and the Azores (Azores High). tilted, and thus the angle between surface. This results in the seasonal lows line-up like a string of pearls way towards the Mediterranean, they often finally blast cc S o ci the plane of the Earth’s orbit around temperature contrast and also ro Locally, low-pressure troughs and over the North Atlantic, and out to sea as a full-force storm. The most famous of these c cirocco co S K h the sun and the plane of the equator affects atmospheric circulation. After a m high-pressure ridges interrupt this frequently supply most coasts from ‘katabatic’ and ‘jet-effect’ winds is the Gulf of Lyon’s s Gh i varies by 23.5° through the year. This Summer Solstice – 21st June in the n ibli general flow of south-west to north- tilt and the Earth’s annual rotation Northern Hemisphere – the point of Northern Spain to Scandinavia with ‘Mistral’. Once its cold and dry air streams down the westerly winds with their subtropical around the sun create the seasonal maximum insolation gradually creeps great winds. Spring and autumn also Rhone Valley, Provence’s tourist beaches transform into or Polar air-masses. Where the cold change between summer and winter. southwards until Winter Solstice on bring plenty of waves as the storms challenging wave-spots in no time. The Mistral winds and warm fronts border, their air- Over the course of a year, the point 21st December. This essentially drives build up a persistent Atlantic swell blow down to Sardinia in the Eastern Mediterranean and of maximum solar irradiation crosses the migration of the global climate Mediterranean wind systems masses meet to produce precipitation the equator twice on its travels machinery complete with it‘s wind to pound the European coastlines. Minorca in the west and can occasionally reach all the way Framed by high mountains and hot landmasses, sandy load suddenly darkens the sky. This at any time of year. Thus Northern between the Tropics of Cancer and and weather phenomena. Strong winds also whip-up North to Sicily, 1000km south. The ‘Tramontana’, Mistral’s little every region in the Mediterranean boasts its wind has many names; insouth-east Spain it’s Europe experiences very fluid Sea and Baltic waters to maximum brother, is confined to the area between Montpellier and the own wind system. Of all Mediterranean winds, called “Leveche”, in Morocco, Algeria, and the ‘Scirocco’ is particularly unusual: This Tunis “Chili”, in Libya “Ghibly”, and in Egypt it’s weather conditions. wave heights. Conveniently, the Spanish border. Both Mistral and Tramontana winds are dusty Northern African desert wind blows known as the “Khamsin”. During summertime, the lows track way up north. Therefore Denmark thermometer reads ‘good to go’ too! While spring may promise warming less common during the summer than the colder months of only 1-5 days a month towards the coasts of A similar phenomenon is witnessed on the and Western Scandinavia in particular, alongside Ireland and Scotland, sunshine, water temperatures are definitely higher during autumn. the year. Southern Europe along a northbound ‘Saharan Canary Islands. Even though driven by entirely Low’. The hot Scirocco picks up increasing different weather conditions, the name and In contrast, the Strait of Gibraltar is a safe bet during the moisture the further it travels across the sea. effect are the same; a Scirocco laden with L summer. This narrow Strait is less than 14km wide and can Coming from the south-west to south-east, its Saharan dust. have nice jet-effect winds. Sometimes for days or even weeks at a time, the easterly ‘Levante’ whistles through between the southern and thunderstorms. These vivid lows repeatedly alternate with friendly L edge of the Azores High and the North African heat low. Southerly winds highs. The Mistral and Tramontana now frequently assault the Gulf of predominate at most other spots along the Spanish Mediterranean coast Lyon, as does the brisk ‘Bora’ – a cold katabatic wind that blows stiffly off due to the summertime land-based heat low. the Dalmatian coast. Overall, the Mediterranean wrestles the “Europe’s Wind conditions differ in the Eastern Mediterranean. From May to Stormiest...” title from the North Sea and the Bay of Biscay. L September the barometric pressure steadily falls between the Azores Ridge Spots on the Canary Islands, Morocco, and the Atlantic side of the L H in the west and the low in the Middle East. This low is not comparable Iberian Peninsula are treated to big wave sets during winter, though the to the cloudy low-pressure systems of the Westerly Wind Zone though.