IDO

GFS still stalling on cold but it is surely only a matter of time till the whole UK gets colder. Next week, with the origin of the jetstream coming from Northern Canada there should be, comparatively, a lot colder weather for Scotland, and possibly a little further south. However this is still zonal weather and we need to lose this to get more interesting stuff. With the AO/NAO both forecast to be moving towards neutral, the delayed effect of stratospheric warming, the coldest part of the winter, these are all positive signs of a change. The best call is for the change in 3-4 weeks but ECM are a bit more presumptuous, so any change could start to show up in FI quickly. How much cold, and for how long is the the big question?

i'm dreaming of..., on 25 December 2011 - 13:30 , said: All this about stratospheric warming is a misnomer. The higher stratosphere has warmed but made nominal impact lower down. It has now been forecast to return to normal at the higher level. Not by the 3rd Jan but it is on its way down. The forecast for 30th December is T (90N-60N) = 11.52 and compare this to the 3rd Jan = 6.04 (at 1hPa).

The plethora of statements saying real cold is on the cards needs some clarification. "LOOK AT THE NH CHARTS GFS AND GEFS POST T300 !!!!!!!!!!!!!!!"...bluearmy I have had a look and cannot see any change to real cold; yes a lowering of temps from the mild at the moment but nothing that is statistically relevant for nearly mid Jan. GFS & GEFS all have average to cool for Birmingham & London. Even the CFS ensembles have the mean temps around average till Jan 19th; slightly colder from around the 12th for Scotland (& the North?). From the 19th I suspect that colder weather will move down further south, but it is likely to be settled cold rather than anything wintry. From very late Jan we will need the stratospheric warming to have dug into the models otherwise the continuation of a very average winter?

All this about stratospheric warming is a misnomer. The higher stratosphere has warmed but made nominal impact lower down. It has now been forecast to return to normal at the higher level. Out in FI there is a suggestion of another warming episode but that is then and we are now talking about the current output. There is likely to be no effect from warming in the next 3-4 weeks. So if there is a change due please be more specific as I am unable to see where from. It looks like cold zonal up north and cool zonal down south till the end of FI (Jan 10th). A glance at the last FI in GFS has the Jetstream above the Orkneys with no clear blocking patterns. Scanning the professional forecasters none of them are predicting any cold spell in January. The plethora of statements saying real cold is on the cards needs some clarification. "Cheese Rice" Thanks for posting the ensembles for Aberdeenshire, very helpful for about 0.5% of the population. The same graph, for the same period, has max temps, for London, between 2-7C; pretty much average to cool.

Certainly FI is looking more interesting but I don't see any fundamental change yet. It looks like there is more emphasis on cold zonality and as we are heading for mid January this is not a surprise! I suspect there will be snow for the usual suspects. Whats to stop the HP toppling over the UK as the GFS run extends; bringing the Jetstream back north of the UK? I don't see that being blocked off. Anyway all this could change, good or bad in the next week and clearly, all caveats aside, at the worst this will generate some interest.

The latest Weatheronline forecast, that goes to the last week of January (issued yesterday) has HP still dominating our weather; ends on the 24th. Maybe "some fog & frost", hardly what patrons expect when you suggest "cold". Can you post models that show cold weather for mid Jan through Feb please? Or is it a hunch? The Law of Probability? Tea Leaves? I would say there is no greater chance of seeing cold this Feb than any other year; if anything I would lobby contrary to your statement: the CET for 2011 is likely to be the second highest ever thus suggesting a pattern of warmer temps. If it is based on stratospheric warming then this is unlikely to happen till Feb, as the models are now downgrading the current indications, and the next alternative is mid-Jan...and of course that maybe downgraded. Then, we have to hope the warming goes to the lower levels, which may take 2/3 shots. Then we have to hope the block(s) build in the right place and by then we are near Springtime. Now I am not precluding a snow event in the second half of winter, but this is a model thread and nothing in the models are indicating a juxtaposition of the current synoptics, and relying on a possible warming event should be judged if and when it happens. The previous statement is meant in good nature and may stray off topic. Although they are strongly worded they reflect the nature of my writing and are not meant to damn or incense any member. They are my thoughts and may or may not be judged as the ramblings of a mad man when we have the benefit of hindsight. A Merry Christmas to all.

Zonality for sometime now and for the foreseeable future. As it implies there may be some wintry stuff on the back edge and yes it may slip a little bit further south, but overall, for many of us (down south) it is rather uninspiring. However there appears to be a trend to lower the latitude of the jetstream and for it to cool, so the synoptics may improve for the final half of Winter; though this is tempered by the final frame of the GFS (9th Jan), that doesn't promise a lot in the short term. "Patience is the companion of wisdom"

The latest FI in GFS is Fait Accompli as far as I am concerned. The models are consistently a derivative of a carousel of mediocrity. Each output mimics the other, with the delivery of, say "The Lion, the Witch & the Wardrobe" without that wardrobe. When we find it, then Narnia beckons, but until then, we can only hope... "To travel hopefully is a better thing than to arrive."

Two major SSW in the last 30 odd years, 1979 and 1984. The event tends to affect North America. It takes approximately six weeks from the start of the SSW to effect the USA. The 1979 event was of little influence on the UK weather and although in 1984 the UK experienced a cold January 1985, from what was an Omega Block, this may or may not have been a direct result of the SSW. I would not pin too much hope on an SSW being our Nirvana. Of course it will effect the Jetstream, cooler flow, and I would agree that it is a better setup than the current status quo, however that is still 4-6 weeks away and the models will not cover this till the New Year.

Of course you are not going to complain, I see where you live! Only 11% of the UK population live in Scotland so to base the Winter on what you achieve is really not a good background. The CET is going to be above the long term mean this December, so average at best but compared to recent winters a return to a boring outlook masquerading as a Winter. Based on the FI (as that is all we have) there is very little hope up till mid January. Banality (sorry zonality) to the North and HP to the south of the UK. A bit of frost if we are lucky! Members will say "stop moaning" that's only half of the winter gone. I remember the same people lambasting us for saying the same thing in early November, telling us "it is not even winter yet"! I think the cards have been on the table for a while and no matter how you look at them they are a busted flush. You can keep bluffing but at the end of the day this winter is gonna be a slight for Cold (to the majority of us). I don't mind members drinking from the glass half full mug and I agree there is still six weeks to go (post FI) but every day the FI ticks off another winter's day, with another denunciation for cold, I do wonder if it is telling us something, and maybe many of us are not listening hard enough. "Veritas vos liberabit"

You think? No, that is just zonal, we get 48 hours of cool/cold as a low slips by. This will probably be downgraded as we close in. What follows is a reset to a high that will give us average/mild temps. That will concentrate us for a week before more zonal? Then we are in the last two weeks of January. This is when there will be a change if there is going to be one. That's when the cold pool will reach North America, a result of the stratospheric warming. If things don't pan out and the blocking fails then, I will resign myself to the fact that this Winter will be average.

"The Lord giveth and then taketh away" The last two GFS were a surprise but 06Z is back on track with HP influenced weather and any attempts for the cold sinking south sent packing.

Well if anyone can be upbeat about FI in GFS I want what they are on. Dross for the next 21 days. Lets not beat about the bush, its awful. With little hope further into January we are facing mild-armagedeon ad nauseam. Bring on Winter 2012/13. Wheres my sun lotion? Missing you already...see you next November.

Since September the AO has been positive for over 90% of the time. This is a strong pattern and this will dictate an average winter the majority of times. I have seen little evidence in the medium term that the AO will turn negative, other than fleetingly. ECM predicted the blocking in the last two years but they have not forecast it this year. Although there is warming in the higher stratosphere this has not percolated down to the lower end so the PV looks like remaining strong.Therefore Northern Blocking looks an outside bet for the next four weeks. Currently to our East temps are mild compared to the last few years. Any Easterly feed from a Northern based HP is likely to reflect this and we are unlikely to experience any real cold. The current setup precludes any prolonged cold and that is what I have commented on. When we have an improvement in the synoptics it is then we can post as to the likelihood they will lead to cold.

Sorry, that's all I had to go on. At this time I was just commenting on the FI by GFS and as there was close to 100% confidence by the ensembles at Day 8 I therefore extrapolated that, confidence at +384 would be of relative significance.

There is little in the way of cold, maybe transitional cool in Scotland. The ensembles (GFS) have 100% confidence that by the 30th we will have a HP to our SW and be influenced by relatively mild weather. A week later the HP is slightly further East with above average temps. The end of GFS has no short term route to cold. In fact with the Jetstream way to our North, quite the opposite; aided by two HP's moving in to the picture from the SW and South. (I usually am skeptical of FI but in the current setup the confidence is quite high). It looks like above average temps for the first half of Jan 2012. Something need to change in the next two weeks or the second half will also be a write off for cold. So effectively six weeks of Winter left...

Members are knocking other members comments that relate to the current GFS model (and others). They clearly point to a HP near or close to us with Southerly or SW winds till the end of FI. The Jetstream is pushed to high latitude and as of end December we are stuck with this long term scenario. Now of course things can change, etc,etc...However the models have been very good since November barring the specifics of lows axis (and you can't knock them for that). Its the pattern that we go to the models for, and they are now pointing to a powerful Azores High being reinforced by highs from the west. Exactly the problem we had in October/November. “ If it looks like a duck, swims like a duck, and quacks like a duck, then it probably is a duck. â€

I think the next 36 hours are being forecast with higher confidence now. As for the next few weeks FI has been consistent with a HP to our SW giving average to mild nothingness. There must be very high confidence in this now despite the cool outliers that keep propping up the interest of the glass half full coldies. From the end of FI ( end 2012) it looks like we are weeks away from any cold. Lots of forecasters have been saying we will have to wait for mid Jan till we get some cold and this does now look the earliest opportunity.

GFS in FI now defaulting its Op run to what many of us have been suspecting: a high in the SW giving average/mild weather till after Christmas, after we get over this transitional cold over the weekend. This is the most likely scenario, so no surprises. It is always fun to look for cold but it just does not look like its going to happen this December.

Keeling Block: http://www.weatherweb.net/wxwebtv2.php

...its transitional blocking as HP washes over the UK by the 20th. This is on a SW/NE track. Taking us through to Christmas with above average temps. Looks like zonal in the build up to the New Year. Back to square one for 2012.

GFS so close to the Keeling Blocking next weekend. Giving a snow event next Saturday for Scotland. And the front pushes down into the Midlands Sunday; cold enough to snow here. The ridge is still very close by Sunday afternoon allowing snow to reach the South.Interesting as we enter FI.....

Yellow is weather advisory. It is one step away from a warning (orange). I suspect you will not see the worst of the storm.

GFS in FI not interested in any blocking (again does tease us but I suspect the current synoptic setup bias' the model to reject that scenario). Brings HP in from the SW giving us a relatively mild pre-Christmas week. Another HP from the SW follows by Christmas day influencing the South, with cool zonal deja vu for the north. By the end of the run it is rather messy with the two aforementioned HP's joining forces, settled over most of Europe with the zonal line, Midlands Northwards. From that position little hope of any change till the New Year. This probably has reasonable confidence even though the axis of next week's LP's could influence the upstream patterns; as even with subtle changes to the hit zone I cannot see anything but transitional blocking at best (based on the GFS models), and bearing in mind relative agreement within the models, blocking looks unlikely in the medium term. The zonal flow looks like its going to be as dominant as the HP was in October/November. As for the two LP's next week I believe the Met Office will push its warnings to North of the M4 corridor. so the South should escape the worst again. As for Friday, too early to say, but again based on the recent three LPs, the nearer the time, the further North they tend to be centered.

I think it is relatively easy over the last two months to predict the FI. The models have been very good. The set up in November was easy as it was HP all the way and December has been easy; cool or mild zonal. Again looking into FI of GFS has been a worthwhile exercise. Obviously the finer points like where the lows track are harder to get right but most of us understand that and are just looking for a general outlook. The Met Office appear to be quite confident that we will be in mild zonal till mid jan. I see nothing to doubt this forecast. Christmas day 12c on GFS.