Winter has actually started not so bad. With snow already in November (actually the end of October), many were satisfied (especially winter sports and snow shovel seller). In particular, the regions along and south of the Alps were a great piece on the Schneekuchen.Von the Ötztal Alps (Obergurgl 160%) over the Alps Gailtaler (K.-M. 200%) to the mountains of Graz (Präbichl 120%) were in November, the rainfall values in some cases significantly above the air target. In December, the flow configuration changed so that up to two Südföhnphasen dominated the northern flow. Two lows Italy provided yet at the Southern Alps for a surplus. The temperatures were - as widely known - especially evident in the northern Alps in the middle. Only in 1996 had a similar cold December.
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| No significant new snow accumulation on the Pitztal glacier since mid-December. The Südföhnphasen (wind striking peaks) at the well peak (3440 m), however, are clearly visible (around 08.12., Before Christmas, and from 05-09.01). |
What about now?
is in the top layers of the Alps since mid-December, no greater amount of snow fell, only the Arlberg region took advantage of their exposure to the west (75%). Bregenz, for example, ended the year with a precipitation increase of 45%, while behind the Arlberg again (dust) was dry: Landeck, 30%, 60% Umhausen Innsbruck after all 90%.
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| The webcam image shows the Krimml pasture at 1600 m more than green, white - no surprise in December there were only about two-thirds of the average precipitation. |
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| More snow is in the west - such as the Arlberg hospice - the snow last night, however, to cover a lot. |
And some speculation ...
The previous days in the new year were of a hairdryer (17 degrees yesterday in Bludenz 09.01.) And high pressure influence marked, the precipitation totals are still in moderate range. The record amount of 18 mm in 10 days on the Galzig is the greatest feeling, many places are so far without precipitation (preferably in the west of a line Nordföhnregionen Julian Alps - Alps Gurktaler - Mur / Mürztal).
What next in January?
The ZAMG has since on 3-month outlook 17.12. (basiererend on ECMWF) made no new outlook. At that time it was said:
"Especially for January is from today's perspective, the possibility of very strong negative deviations." There were already
(date) seasonal forecasts of ECMWF - they remain elect reserved (http://www.ecmwf.int/products/forecasts/d/charts).
worth in this case to look at the freely accessible monthly forecasts of the NCEP (National Centers for Environmental Prediction - NOAA / USA). This weekly recalculated his views and can better address the short-to medium-term changes in the Strömmungskonfiguration of the Atlantic.
The more realistic scenario, namely the large-scale conversion of the weather. This winter so far blocked a massive wedge pressure over the eastern Atlantic, the development of the West Wind Drift, the mean a warmer and wetter weather for central Europe would.
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| prime example of a blocking high over the British Isles. The Azores-depth moves further towards the Mediterranean during Mitteleruopa in the Arctic cold air stays (15 December 2010 00UTC). |
A blocking high is not an abnormal event but one example of the negative anomaly Northern Oscillation Index (NAO) . Iceland Low and Azores High are weaker (negative index), which tends to mean colder and drier conditions often in Central Europe, a below-average cold weather in Scandinavia, warmer temperatures in Greenland and the frontal zone shifted to the south a wet weather period in the Mediterranean.
This weather situation was a persistent (föhnigen) Südwesströmung since 05.01. replaced. The pattern is not tilted back, as was the case in December.
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| flow development to Thursday: The Iceland Deep-shoveled warm, moist Atlantic air to Europe - the cold air is pushed to Skaninavien. |
The NCEP, the transition recorded and therefore not calculated in the legs, which are based on older values (lower panel: top two rows), too cold and dry January, but a damp and medium January temperature in the Alps. That may be on 10 one month no longer be bold prediction, but it points to just two things:
*) to preserve the West Wind Drift
*) is not a throwback to the "blocking high over low" position in December.
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| months of the NCEP forecasts for Europe | | |
country under!
short term, this means the weather and a rapid thaw succession of low pressure through trains. Virtually 24-hour clock Atlantic lows are (Central) would tear Europe and, in addition "changeable" weather always some rain. The situation in the flooded areas (Main, Moselle, Rhine and Danube soon) relaxes not. Special attention is now on the low pressure area that covered the Alps on Wednesday night and also for Austria is interesting.
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| ice cover and snow depth | | | |
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| 96h - Total precipitation JRC - snow line to the 1500 - 2000 m |
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| also the ECMWF it looks like: 96h total precipitation at a SFG between 1500-2000 m |
Both models exist particular for the area of the Northern Alps (Salzkammergut) to the Bavarian Forest and the Fichtelgebirge up to 40 to 60 mm - at these temperatures (5 degrees at 1500 m) in the form of rain. Especially the smaller Danube tributaries (Steyr, Enns, ...) thus threatening towards the weekend to increase the level and thus a slight risk of flooding.
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References:
station during the Pitztal Glacier (1): lawine.tirol.gv.at
Webcam images Krimmler Alm (2) and Hospice Arlberg (3):
bergfex.at various weather maps (4, 5, 7, 8): wetterzentrale.de GFS (NCEP ) 96h precipitation ECMWF (9): bergfex.at
NCEP seasonal forecasts (6): http://www.cpc.ncep.noaa.gov modified by alpen.wetter
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