Astronomy, Photography and Weather
April 23, 2017, 08:55:38 am
Welcome, Guest. Please login or register.

Login with username, password and session length
News: IAA lecture programme continues alternate Wednesdays from September - an excellent programme of lectures- Queens University Belfast - Bell Lecture Theatre. Also keep an eye out for the Summer Events
 
  Home Help Search Gallery Staff List Login Register  

Netweather Winter Forecast 2010/2011

Pages: [1] 2
  Print  
Author Topic: Netweather Winter Forecast 2010/2011  (Read 8211 times)
martinastro
Martin Mc Kenna
Global Moderator
Hero Member
*****
Posts: 5182


Maghera, N. Ireland


View Profile WWW
« on: October 18, 2010, 04:23:29 pm »

Netweather.tv have just issued their long term Winter forecast for UK/Ireland 2010/2011, here are the details...

http://www.netweather.tv/index.cgi?action=other;type=winter-forecast;sess=

Winter Forecast 2010/11
This forecast issued on the 18th October 2010 and written by our long range expert Stewart Ranmping is a technical and in depth seasonal forecast for Winter 2010/11. Usually only available to commercial clients of Netweather.tv, it is being made freely available this year in addition to the usual long range forecasts and features that are available on the site.

Following back to back cold winters for much of the UK, there is a lot of focus whether this year will follow suit. However, with temperatures forecast to be close to or slightly below average, we believe the most significant aspect of this winter will be the very much below average winter rainfall following on the back of a largely dry summer for parts of the UK and very likely dry spring to follow.

Headline Summary:
Anomalously cold ocean temperatures in the Tropical Pacific or ‘La Nina’ conditions have become well established. There is a high probability that these conditions will intensify over the coming months and become one of the strongest La Ninas on record.
With a strong coupling between the atmosphere and ocean signal, global weather patterns are very likely to be ‘forced’ by a strong La Nina with dominant high pressure centres in the northern Pacific and in the North Atlantic.
La Nina winters have a variable influence on the weather in Europe although we anticipate no sustained extremes of cold and the emphasis on dry, settled weather. Some wintry weather is however expected, particularly during mid to late December an early January.
Temperatures are likely to be close to or slightly below average with the coldest weather (relative to long term averages) centred over France and Iberia, the south-east of the UK closest to this cold. Compared to many winters of the last two decades, this coming winter would probably be regarded as cold although not of the same degree as last year or 2008/9.

Background to this forecast:
This forecast is based upon the likely influences of La Nina in the Tropical Pacific, atmospheric signals and air temperatures high up in the atmosphere over the Arctic which are seen as key variables, many of which are dissimilar to last winter.
However, the last twelve months (probably thirteen months after October’s data) have seen a negative or cold phase of the North Atlantic Oscillation (a key measure of the difference in pressure between Iceland and the Azores). This is unprecedented since the index was first compiled in 1950 and reflects a reversal in the normal pressure patterns which played a significant part in last winter’s weather.
This forecast based upon an understanding of the dynamical processes involving the world’s oceans and atmosphere, the use of historical-based analogues and Netweather.tv’s customised seasonal predictive model based upon the Climate Forecast System (National Centre for Environmental Prediction).

Record strength La Nina
Sea temperatures are widely below normal across much of the Tropical Pacific and these colder waters extend to several hundred metres below the surface in the central and eastern Pacific Ocean. This is characteristic of a La Nina event of medium strength magnitude.
The pattern of surface winds and cloudiness across the Tropics is very typical of La Nina event and model forecasts continue to suggest the sub-surface anomalously cold waters will work their way to the surface over the next 2-3 months further strengthening La Nina to ‘strong’ category event, potentially the strongest La Nina of the last 60 years given the large volume of below average waters with temperatures up to six degrees below normal.
Since July, global weather patterns have been very consistent with La Nina. The European weather patterns associated with La Nina in winter are somewhat variable. Most were dry and mild although there were some colder events in 1955/56 and 1964/5.



Atmospheric indicators fully backing La Nina
One of the keys to understanding La Ninas and their warm counterpart El Ninos is how the atmospheric variables react to the temperatures of the ocean and whether or not the atmosphere is ‘going along’ with these changes.
Most atmospheric variables are also exhibiting extreme La Nina like behaviour. Overall levels of storm activity in the Northern Hemisphere is at a 30 year low despite an active Atlantic hurricane season whilst forward intertia in the atmosphere was the third lowest in 60 years during July and August. The pressure differentials measured in the Southern Hemisphere, which usually indicate the future trends of La Nina have been advertising a strong event in the making.
Of the strong La Nina events, these atmospheric indicators suggest we are historically much further advanced at this time. Given feedback loops, atmosphere reinforcing La Nina, La Nina reinforcing the atmospheric variables, it is very likely that an exceptionally strong La Nina event will take place this winter with a probable peak in December or early January.

Temperatures in the stratosphere
One of the key elements of last winter’s cold weather was above average temperatures in the upper atmosphere high over the Arctic which promoted ‘blocking’ highs displacing polar air into Europe.
This year we expect the combination of low solar activity and a westerly wind over the Tropics to be less conducive to blocking highs with colder than normal atmosphere over the Arctic driving polar westerlies which tend to favour blocking highs further south around the UK.

Seasonal Model Guidance (Climate Forecast System)
Model guidance is for high pressure close to or north and west of the UK for the majority of the winter with a slight tendency to shift further away to the west during February.
Model sees average or slightly colder than average temperatures for the UK, coldest in the south-east and mildest in the north with central Europe slightly below average.
Model sees rainfall below average.
Good consistency between model updates and output appears to be consistent with historical analogue guidance adding confidence to forecast.

Winter Forecast details

December
High pressure likely to be centred to the north-west of the UK with winds from the north-west with northerly interludes.
Temperatures likely to be below average, the largest departure of the three months compared to long term averages with the coldest temperatures in the south-east.
Rainfall likely to be much below average.

January
Large area of high pressure in the central Atlantic gradually edging towards the UK although an unsettled phase likely with potential for snow, particularly in western areas.
Likely to be cold to start with fog and frost persistent.
Rainfall below average.

February
High pressure centred over the UK with a lot of settled weather.
Temperatures likely to be slightly above average although surface temperatures may be depressed by fog and cloud.
Rainfall likely to be much below average.
Forecaster: Stewart Rampling for Netweather.tv Issued: 18/10/10



Report Spam   Logged

Social Buttons

markt
Hero Member
*****
Posts: 1416

West Midlands, UK


View Profile
« Reply #1 on: October 19, 2010, 08:35:18 pm »

I do like the netweather winter forecast I have to say - lots of reasoned detail!

I think the thing that interests me the most is the possibility of snow forecast in western regions.  Here in Brierley Hill we had very little snow last year, couple of inches max at any one time, and this forecast - if correct, does favour a bit more of the white stuff in my end of town...  I hope!
Report Spam   Logged

markt
Hero Member
*****
Posts: 1416

West Midlands, UK


View Profile
« Reply #2 on: October 20, 2010, 05:56:28 pm »

Just to add - this is Jo Bastardis blog today from Accuweather...

TUESDAY 11 P.M.
THE WINTER OUTLOOK FOR EUROPE

EUROPE

In 2003, the fierce heat wave centered in France was replaced by a chilly October, and when winter came, much of Europe was warmer than normal. However., the area that was near normal to a bit below was close to where that heat wave was then eastward through southern and southeastern Europe.

This year's August heat wave, like 2003, coming off an El Nino winter the year before, was over Russia and into central Europe. October has been cold in much of this area, and guess what, the winter will be most fierce from Euro-Russia into the Alps. Russian temps as much as 3C below normal for the winter are possible, 1-2 C below normal westward into the Alps. THIS INCLUDES THE BALKANS INTO NORTHWESTERN TURKEY, SORRY TO MY FAN CLUB THERE (I love all of you!!) But I should have been better in my description. I like above-normal snow in much of this area. Most of northwestern Europe will be near to a little below normal (up to 1C below normal) while northern and central Scandinavia, Scotland and Ireland are near or a bit above normal.

Snowfall will be above normal across much of Europe with heaviest in the Alps into Russia, perhaps a bit below normal in northern areas.

To sum up, a severe winter looks to be on table from the Alps into Russia, but winter in Great Britain and Ireland will not be as severe as last year.

Globally. Opposite of last year, the globe will be cooling considerably and temps by spring should be running near or below normal. This trend will probably make 2011 the coolest year since the late 1990s. Arctic sea ice will continue to recover from the 2007 lows, with the summer ice melt season next year probably returning ice to pre-2006 levels.

Report Spam   Logged

markt
Hero Member
*****
Posts: 1416

West Midlands, UK


View Profile
« Reply #3 on: October 25, 2010, 08:18:39 pm »

Here's a video for the winter forecast...

http://www.accuweather.com/video/646598930001/the-euro-winter-lets-not-get-too-carried-away.asp?channel=vbbastaj

Hmmm  Sad
Report Spam   Logged

markt
Hero Member
*****
Posts: 1416

West Midlands, UK


View Profile
« Reply #4 on: November 06, 2010, 10:13:23 am »

Netweathers latest long range update covering early winter...

http://www.netweather.tv/index.cgi?action=longrange;sess=
Report Spam   Logged

martinastro
Martin Mc Kenna
Global Moderator
Hero Member
*****
Posts: 5182


Maghera, N. Ireland


View Profile WWW
« Reply #5 on: November 06, 2010, 02:55:17 pm »

Not a very exciting forecast at all  Cry - not great for snow lovers but maybe good for freezing nights, fog, ice etc...the closer we get to this Winter the less I'm liking it, doubt we will get anything like last year...but we shall see  Smiley
Report Spam   Logged

markt
Hero Member
*****
Posts: 1416

West Midlands, UK


View Profile
« Reply #6 on: November 16, 2010, 04:25:38 pm »

It doesn't get anymore exciting for us either reading Joe bastardis latest blog entry either Sad

.....


HELLO, EUROPE... NO CHANGE IN WINTER IDEAS ON THE THREAT OF BRUTAL COLD ALPS INTO SOUTHERN RUSSIA.
By the way, you can follow me on Twitter (I am @BigJoeBastardi). I occasionally tweet there on Europe when I don't have time for monster posts. In fact, I tweeted today.

I see nothing to back away on the idea that the core of the worst of the winter is in southern Europe into southern Russia this year. Most of the "continent" is cold and it's Ireland, northern and central Great Britain and Scandinavia that has the shot at warmer than normal. It will be a tussle in Brussels, but once south to Vienna and Berne, it's the cold that will turn people into non-believers (if they have not had enough already) that may be warm, warm, warm is not the way to go. I also think the winter is cold from Italy to Turkey. The threat of cold is no bull in Istanbul.

Having my way with words here.

In fact, I am so impressed that I think my relatives all the way to Bari, Italy, are going to see it snow this year.

For my amigos in Madrid... look out, a cold Spanish winter is on the way. In Greece and Cyprus, colder than normal. In fact, from about the 50th latitude south, this looks nasty, but centered between 40 and 45.

If you like winter cold... you'll love what's coming.

Ciao for now.

****

Report Spam   Logged

markt
Hero Member
*****
Posts: 1416

West Midlands, UK


View Profile
« Reply #7 on: November 16, 2010, 04:32:25 pm »

Sorry to double post...

Here's Joes latest video blog

http://www.accuweather.com/video/677466324001/hey-europe-the-arctic-hound-is-getting-ready-to-howl.asp?channel=vbbastaj

Maybe we have an arctic blast coming sooner than we expected?  Would be nice to see some snow as we head into december.  Fingers crossed!!!  Roll Eyes

Report Spam   Logged

martinastro
Martin Mc Kenna
Global Moderator
Hero Member
*****
Posts: 5182


Maghera, N. Ireland


View Profile WWW
« Reply #8 on: November 16, 2010, 07:49:26 pm »

Thanks very much for the link Mark, really enjoyed the video update from Joe - by the sound of things we are not going to get an exceptional Winter so far which is rather disappointing, however I am interested in this next cold plunge in the near future, Dec snow can be very interesting. Worth keeping an eye on that  Smiley
Report Spam   Logged

JohnC
Hero Member
*****
Posts: 1631

Gloucester : UK


View Profile
« Reply #9 on: November 16, 2010, 08:07:47 pm »

 Maybe We could come back to these forecasts as events unfold soon with a winter chill here by the end of next week being forecast by Joe B-I assume he means 25th.-28th In this last video he says he doesn't agree with the current US models showing  that a  very cold winter will be over Scandinavia and the UK as well as the rest of Europe so there's a fault line from the outset. I've seen these seasonal forecasts fall flat on their faces  often enough ,I just take it as it comes, unfortunately business relies on forecasters to either increase or decrease production, so which forecasters do they listen to ?
Report Spam   Logged
brianb
Hero Member
*****
Posts: 1228



View Profile
« Reply #10 on: November 16, 2010, 10:28:35 pm »

Quote
I've seen these seasonal forecasts fall flat on their faces  often enough
Yup. Total waste of time IMHO.

Even if they're right and the seasonal average temp is 1C higher or lower than usual, you're unlikely to notice. It's the "three sigma" events that catch your attention, and you can get an exceptional cold blast in a warm winter or vice versa.
Report Spam   Logged
markt
Hero Member
*****
Posts: 1416

West Midlands, UK


View Profile
« Reply #11 on: November 17, 2010, 07:41:53 am »

I always take these things with a meterological pinch of salt too, however it is interesting to see how the forecast develops with time - could be right, could be wrong I know.  I think the thread is useful to be able to have all these ideas in one place - if anyone else has any alternative forecast sites / links please post them up so we can see how they compare.  Tis' all good fun!  Roll Eyes


Lets see if Joe is right about the end of the month - i hope so!  Wink
Report Spam   Logged

martinastro
Martin Mc Kenna
Global Moderator
Hero Member
*****
Posts: 5182


Maghera, N. Ireland


View Profile WWW
« Reply #12 on: November 19, 2010, 12:44:19 am »

Next week looks stunning for a deep cold spell and snow showers  Smiley
Report Spam   Logged

paulster78
Hero Member
*****
Posts: 752


Omagh, N. Ireland


View Profile WWW
« Reply #13 on: November 19, 2010, 12:54:34 am »

Indeed Martin, mouth watering actually!  Smiley
Report Spam   Logged

martinastro
Martin Mc Kenna
Global Moderator
Hero Member
*****
Posts: 5182


Maghera, N. Ireland


View Profile WWW
« Reply #14 on: November 23, 2010, 04:11:44 pm »

Updated Winter forecast from NW....

http://www.netweather.tv/index.cgi?action=other;type=winter-forecast;sess=

Still sounds wishy washy to me and so unspecififc that it's quite useless
Report Spam   Logged



Pages: [1] 2
  Print  
 
Jump to:  

Powered by EzPortal
Bookmark this site! | Upgrade This Forum
SMF For Free - Create your own Forum | Buy traffic for your forum/website

Powered by SMF | SMF © 2016, Simple Machines