On Friday, January 3, 2014 10:03:44 PM UTC, Keith (Southend)G wrote:
On Friday, 3 January 2014 21:55:31 UTC, John Hall wrote:





Of course late January is often a favoured time for such a change. One



thinks of 1947, 1956 and 1986. In 1947, if one looks at the chart for as



late as 17th January, it's a classic zonal picture with little hint of



what was to come:







http://www.wetterzentrale.de/pics/ar...0119470117.gif







But by the 22nd high pressure had drifted north over the UK and



established itself over Scandinavia:







http://www.wetterzentrale.de/pics/ar...0119470122.gif







One wonders, if the current computer models were run with the old data



for January 1947, would they have predicted the change. (Of course back



then there wasn't any satellite data, which would handicap the models,



though I suspect that if anything there was better surface data. They



had the ocean weather ships, for one thing.)



--



John Hall "He crams with cans of poisoned meat







Why do we punish ourselves every winter :-)



Keith (Southend)

http://www.southendweather.net

"Weather Home & Abroad"

twitter: @LawnscienceEssx

"We"? Punish"?? Heh! If you must!

For me, it's looking at weather models and seeing when there is consistency and agreement enough to forecast with accuracy at 10 days. It matters not whether it is winter, or summer. However, if you look, for cold and snow in a UK winter, because you like cold and snow and want cold and snow, you will be disappointed much of the time with the model output and that disappointment may well "punish" you, but please don't include me in that masochistic way of looking at things! *))

Some chances of a change at 10 days, in the 00z ECM, but it's a zonal outlook on the 00z gfs. I'm still fairly happy about my forecast for the 12th, but the chances of it achieving outcome have not increased in the last two days.