O prognoza a unuia dintre "guru" de pe theweatheroutlook.com, numitul Gavin P. Se refera in primul rand la UK, dar are descriere sinoptica:
Winter 2011/2012 Forecast
This forecast is based on the following points:
1. Extended, weak solar activity and still below normal, but increasing sunspot activity.
2. Weak La Nina persisting into the middle of winter, before fading back towards neutral by spring.
3. Cold PDO/Warm AMO combination similar to 1950's (this is a wild card because it looks like the AMO is becoming neutral or cold, which tends to favour troughiness over us, particularly when combined with La Nina)
4. October rainfall coming out at 94% of the average for England and Wales.
5. Active hurricane season.
6. Above average, but rather late snow cover across Siberia.
Most of the pointers I look at to compile a winter forecast are telling me the winter of 2011/2012 should be colder than average.
It would be very unusual to get a fourth colder than average winter on the bounce, however, I cannot ignore my methodology. So this forecast is going to predict a colder than average winter.
I'm thinking at least two of the three winter months will be colder than average.
DECEMBER:
I'm expecting December to be rather disturbed in the first half of the month, with quite deep areas of low pressure moving into the country producing wind storms,heavy rain and possibly snow. We should see big temperature variations during this period
Sometime around mid December I think we'll get a spell of high pressure, initially producing a mild, dry spell, but tending to become colder as the high becomes located over the country.
Christmas itself could be dry, cold and frosty with very little if any snow lying.
Between Christmas and New Year I expect a cold snap to develop, probably from the north, with wintry weather for many.
CET Temperature 0.5c above normal. Precipitation 100% of the average.
JANUARY
January might see cold and mild weather waxing and waning, but as we go into the later part of the month the emphasis will increasingly shift towards cold.
The New Year period should be cold and wintry, but then I'd expect a thaw as the weather becomes more Atlantic dominated for a time.
Mid month onwards we're at risk of increasingly cold and snowy conditions, though milder Atlantic air should push in for a time, once again.
The end of the month may turn very cold as a big area of high pressure develops over Scandinavia and brings winds around the east.
Temperature 1.0c below average. Precipitation 100% of the average.
FEBRUARY
February looks potentially the coldest month of the winter with high pressure dominating over Scandinavia and possibly Greenland also. The NAO/AO may go extremely negative, locking us into a prolonged and very cold spell of weather.
The first half of February may be the sevierest spell of the winter, with maxima staying around freezing all day and lots of snow and severe frosts as well.
The second half of the month should find low pressure attacking from the south-west as the blocking highs slowly lose their influence. So gradually it should turn milder with snow turning more to rain, though this could be a pretty slow process.
I think we end the month on a milder and unsettled note with snow confined to upland northern regions.
*I think there is a small, but not insignificant risk of February being a severe month on a par with Februaries of 1956 and 1986. At this stage I would rate this chance as around 25%. What goes against that risk is that I think the Atlantic will be attacking from time to time later in the month. This increases the risk of snow, but perversely also stops the cold from becoming too severe for an extended period.*
Temperature 2.0c below average. Precipitation 100% of the average.
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