[Blog] Alps Weather Blog 21st December 2012

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<strong class='bbc'>Alps / Europe Past week </strong><br /><br />The forecast last week suggested a rather variable week with fluctuating freezing levels and snow conditions. <a href='http://www.snow-forecast.com/overviews/tips_full' class='bbc_url' title='External link' rel='nofollow external'>http://www.snow-fore...views/tips_full</a> as usual gives the latest conditions, and by midweek much of Europe had seen fresh snow, especially on higher slopes, however this have deteriorated further west as milder weather has started to push back in.<br /><br /><strong class='bbc'>This week for the Alps in Summary - </strong>The trend towards milder weather increasing for the start of the forecast period, and with 850HPA temps of over +10c at times, no surprise that it will be very mild or even warm for a time. However it is set to turn much colder on Christmas Day and at this stage fresh snowfalls are expected in many areas. Thereafter quite cool weather with further precipitation, this largely falling as snow on higher slopes, perhaps rain at some resort levels.<br /><br /><strong class='bbc'>Synoptic Analysis</strong><br /><br />Starting with today's chart for a base point.<br /><br /><br /><strong class='bbc'>Sat 22 December -</strong><br />The seemingly omnipresent Russian High is still in place (1044mb), this gives very cold weather for Russia Scandinavia and Eastern Europe, not quite so cold as you move further west. there is low pressure over Svalbard (988mb), with a surface High Pressure over Greenland (1036mb). There is High pressure over the western half of the Atlantic. Over the main part of the Atlantic there is a deep area of Low Pressure (980mb). Finally the Azores High is over Iberia and much of Southern Europe. This means a very mild flow into much of Western Europe, Due to the very mild air, this gives further very heavy rainfall for the UK. The Alps not for the first time in-between the weather systems, mild for western areas, cold further east but turning milder across the Alps.<br /><br /><br /><br /><strong class='bbc'>Sun 23 December -</strong><br />Since Saturday the whole pattern moves further east by around by several hundred miles. The Russian High Pressure a bit further east (1036mb) so still very cold over Russia and Scandinavia, deepening low pressure over Svalbard, with High Pressure building further over Greenland, the High Pressure block slight further east than yesterday. Still low pressure over the Atlantic, 980mb over Northern Scotland another centre 984mb over the Mid Atlantic. Not quite as unsettled over the UK, W/SW winds over the UK and Northern Mainland Europe. generally mild over the UK, very mild over much of Northern and Western Europe, including the Western Alps, while mild over Eastern Alps and generally much of Eastern Europe. The Azores High ridges into Iberia and gives some warm air here (+10 850Hpa)<br /><br /><br /><br /><strong class='bbc'>Mon 24 December -</strong> The Russian High continuing to edge east, with the very cold air continuing to edge Northwards and Eastwards. Low Pressure over the UK (980mb), cool/mild here, with extremely cold Northerly winds to the North west of the UK with High Pressure over Greenland. To The South East of the UK, South West winds over much of Europe, with very mild or mild winds for most of mainland Europe including the Alps.<br /><br /><br /><br /><strong class='bbc'>Tue 25 December -</strong> A continuation of the South eastward movement of the pattern. Surface High Pressure (1052mb) over Greenland, Deep low pressure over Svalbard through the UK and Scandinavia, pushes down some extremely cold air southwards. North West winds over the UK and North West Europe, cold over Northern UK, cool for much of the UK, mild over of Northern Europe. the very mild air in the far South East of the UK.<br /><br /><br /><strong class='bbc'>Wed 26 December -</strong> The Russian High for the first time in ages, largely out of picture. again very cold over Svalbard, but with more a zonal west to east flow further south, so the very cold air never reaching the UK. A generally flat pattern over much of Europe as well, with the Azores high in place. Very cold over Scandinavia, cold over Northern Europe, cool over much of Europe.<br /><br /><br /><br /><strong class='bbc'>Towards Weekend -</strong> A bit of uncertainty at the moment, a  Greenland High seems likely as does very cold unsettled air over the Svalbard areas, possibly again it looks as if the coldest air remains trapped over High latitudes.<br /><br />The Current guidance is for. Low pressure over the Atlantic, with the UK on the South Eastern edge, as for much of Europe so mild SW winds with a Bartlettesque High Generally the further east you go, the colder it is, especially into Scandinavia and NW Russia<br /><br /><br /><br /><strong class='bbc'>Alps Detail</strong><br /> <br /><br /><strong class='bbc'>Sat 22 December -</strong>  Rather day to start mostly but some moderate precipitation for the early hours for NE Austria, however more general precipitation pushing from the North West into the evening into French Alps, much of Switzerland and W Germany. Freezing Levels 1800m-2100m (west). 1500m-1800m (central), 900-1200m (Austria inc A], however turning milder during the evening, 2400-2700m (west), Snow level for evening precipitation 2200-2500m.<br /><br /><br /><br /><strong class='bbc'>Sun 23 December -</strong> Precipitation moving Eastwards for Northern parts of the Alps during the morning, with 6 hours of precipitation for most areas, and bring over Austria by noon. Freezing Levels 3000m-3500m (west). 2500m-3000m (central and West Austria inc A), 2000-2500m (East Austria), Unfortunately the very mild air, means snow will be reserved for the highest slopes. The Precipitation will continue in Austria only slowly away for Eastern Austria later.) Also it could be warm in places with the foehn effect.<br /><br /><br /><br /><strong class='bbc'>Mon 24 December -</strong> A largely dry day, with only some light showers under High Pressure, probably not amounting to that much. Freezing Levels 3000m-3400m (generally inc A). Locally a bit lower aorund 2500m. Also mild overnight as well.<br /><br /><br /><br /><strong class='bbc'>Tue 25 December -</strong> A cold front edges in from the North West during the morning, reaching Switzerland. Western Austria, SW Germany, and the France Alps by noon, with the heaviest precipitation to the eastern end of this, Freezing levels, falling from the west, North and West 1200m-1500m, further SE, 1500-1800mm [inc A], to South East parts of the Alps 1800-2400m , slightly higher to the far East of Austria.The precipitation edging further east during the evening, into Austria and as it turns colder from the NW, snow levels down to around 1000m. Further showers into France and Western Switzerland<br />So in summary a mild start to the day, but turning much colder, with fresh snow for much of the Alps by the end of Christmas day.<br /><br /><br /><br /><strong class='bbc'>Wed 26 December -</strong> A bit more unsettled with some showers or more general periods of precipitation during the day. Perhaps more in the way of frontal precipitation in western areas again later, Freezing levels, North and West 1100m-1400m [inc A], 1400-1600mm for more central areas, 1600-1800m , for parts of Austria.<br /><br /><br /><br /><strong class='bbc'>Towards Weekend -</strong> Looking generally unsettled with further periods of precipitation, more especially toward the western half of the Alps, Freezing levels 1400-1800m generally on Thursday, at this stage on Friday colder towards the North east, Freezing levels 800-1200m, closer to 1600-2000m in South West.<br /><br /><br /><br /><strong class='bbc'>Outlook - </strong>At this stage a South west wind setting up under a Bartlett high, soi Freezing levels rising once more.

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