I think they'll be changing from run to run, too. As you say there is questions marks over the reliability of those sorts of forecasts 

Anyway, his moan is in the wrong thread 

no but frost is very normal even in week winter northerly's down here thanks to the usually clear skies.

Come on GFS, why do you keep throwing out a crazy MJO forecast that causes way too much momentum to be added from an early stage in your output?

We really are seeing hectic times with the models but none more so than that one.

 

However, the shortwave drama with respect to the U.S. trough is worth talking about.

GFS is keen to have that feature linger right in the way of the mid-Atlantic ridge as it tries to rebuild in 4-5 days time, adding to the Atlantic steamroller effect already occurring in response to that dodgy MJO outlook.

Yet ECM has been insisting that it will be quickly absorbed back into the U.S. trough, meaning a slower pushing aside of the ridge - and no toppling, it must be noted. It just relocates in the vicinity of the UK and then looks to build north - not a bad outcome really, seasonal at the surface after an increasingly wintry working week.

 

Now to make things even less clear, we have UKMO and GEM transferring that shortwave across to the UK trough and allowing the ridge to build in behind it. This could be the best outcome as it adds another precip maker into the mix - provided that low follows the right track of course. It may also help to get more of a S-N jet alignment west of the ridge with greater poleward extension possible before it shifts east. That improves the potential for a fast transition to a Scandi ridge while the UK trough departs into central Europe.

 

Eyes on ECM to see if it goes with that idea, sticks to it's 00z solution, or - and this really would suck - sides with GFS with respect to that shortwave.

GFS aside, I'm still seeing a lot of scope for the cold to hang on through next weekend, even if it becomes dry and clear. Perhaps some hard frosts and ice to experience following the wintry precip Thu-Fri? With luck some places could have lying snow to add to that effect.

 

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J F F

P1 gives us a Channel Low lol

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those do change from run to run and are reflective of the corresponding model run even if they are automatic rather then human. So whether you like the moan or not it's still as relevant as those ramping up cold. 

And for what it's worth they have not shown a single frost yet to date. 

Just for fun but looks like it's lucky 7 from the GFS tonight:

This is one of a handful that follow UKMO with the shortwave behaviour earlier on. 

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GFS 12Z is a mild outliar

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From an IMBY perspective I want to see the cold arrive down here first then worry about how long it lasts.
The models are throwing up messy solutions that are not making it easy to forecast beyond a few days with any real confidence in my opinion.

Some of you lot make me laugh- output like today's prior to 2010 would have had this forum in meltdown.
It's turning colder and there is precipitation in the mix. Relax, enjoy and who knows, you may be watching the lamp posts a couple of times next week?

I knew it. Deliberately misleading.

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This week the models have been rather at sea.For the next three weeks I shall be at sea myself.Unfortunately for a dedicated snowy/cold ,this means missing the first cold spell of the winter.I do hope that it delivers some snow as well as colder temperatures.Three may be other cold snaps before the end of the month or indeed a continuation of the current one.I always look carefully for signs of ridging to Scandinavia around the 19-22nd of Jan ,as this was he route to the bitter February 1947(no ramping intended).
Overall however I think January will on average be another NAO + month.
Which brings me to February.In the last 25 years there have only been three below 3C - 1991,1996 and 2010.The met office have been pretty good with their broad forecasting so far this winter.They are still talking about February being the best month for a more blocked circulation.I hope they are right and look forward to returning to a Britain under lying snow.

Well, after a fun day with the wolves (tip: if you're around a wolf, avoid wearing Lynx Africa as it seems to excite them), I've been able to look at the control run from the ECM this morning.

From 144 to 204 it shows high pressure to the west, with a couple of lows running southwards over the North Sea - this leads to a messy mix of rain, sleet and snow for the SE quarter of England.

The high then moves over the UK, with the cold air aloft slowly mixing out. By 300 it builds to the north, drawing NE'lies and easterlies over the UK. Thicknesses have risen to over 540dam in NE Scotland by this stage and they're above 528 across the UK.

High pressure then remains over the UK all the way to 360, with thicknesses falling very slowly.

The low temperatures on the control were thus the result of snow on the ground followed by high pressure - an ideal recipe for some noteworthy low temperatures at this time of year.

 

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9 and 17 are also very good others as well so it will be interesting to see where the Op and Con sit

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Cheers Roger......Enjoy your trip and hope you come back to a Winter Wonderland

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Simply fascinating output at the moment. The models are really struggling to get to grips with the synoptics and just about anything could come from this, including an elusive easterly. The likelihood of the Atlantic simply pushing back through early next week in the south appears to be deminishing run by run. UKMO still looks half decent at T144 and GEM toys with a brief easterly. GEFS 12z shorts are also an improvement on the 6z which in itself was better than the 0z! Still plenty to play for me thinks in the south, whilst the north is going to get some far more seasonal weather for the next week at least. 😀❄️

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GEFS12z update:

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hmm, i would say that although the op is still on the mild side - but not as rapidly mild as the previous runs.  Still a fair grouping staying cold.

 

Overal milder than say 3 days ago, but probably on the colder side of whats been pumping out the past few days - but only just.

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Exactly the same here! I posted in another thread that the south and southwest costal areas could possibly not see a frost all winter. It looks like average or slightly below at best for a couple of days this coming week.

Looking at GFS I'm not convinced with snow potential for next week for this part of the world. 

Obviously lots of room for change, and surface parameters aren't overly reliable that far out. Just for context though, when the bulk of the precipitation moves in on Wednesday night, dewpoints are shown to be above freezing across the whole of England. 

A lot of caution required that's for sure. 

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ECM 12z rolling and looking good at T+96 and better at T+120

http://www.meteociel.fr/modeles/ecmwf.php?ech=72&mode=1&map=3&type=0&archive=0

http://www.meteociel.fr/modeles/ecmwf.php?ech=72&mode=1&map=3&type=0&archive=0

 

Definitely cold enough for snow on that 120 chart - and there's been a recurring theme for LP in cold air next Thursday.

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ECM at 120......I'd take this NOW

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The BBC 5.58pm weather forecaster   dvised that colder air will sweep south during Thursday o the following weekend will be much colder than of late with the potential for snow showers countrywide if I interpreted him correctly.

at 144 ECM has us in a Northerly flow and cold

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ECM168 keeps it cold into next weekend.

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At 168 it looks as though it is going for a reload of the Greenie High:

http://www.meteociel.fr/modeles/ecmwf.php?ech=168&mode=1&map=1&type=0&archive=0

 

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