ghoneym

Evidence of increasing skill score from the ECM and GFS 0000 UTC forecasts as shown by trends in the Anomaly Correlation Coefficient associated with forecasts of 500 hPa height over the Northern and Southern Hemispheres generated 5 days in advance, and verified against 500 hPa height analyses from the originating centres

The cold we tap into comes from much further north. They can keep their warmth while we bathe in cold swathes of ice days

Easterly wind direction with nice cold uppers moving in, nice one ECMWF.

Scotland obliterated by the Chinese model last few days of 2017

Tuesday & Wednesday next week will bring some strong winds but nothing to get too excited about. Typical UK winter low pressure systems bringing blustery to "hod on tae yer bunnet conditions. Friday looks a bit more interesting but a wee tad too far out for me to speculate as to whether anything interesting will come from it. @Bring Back1962-63 keep the posts coming, love your input Cheers

The Azores high Bermuda high in image) is an ever present as can be seen from the image, as is the Iceland low. The jet stream pushes and pulls these systems giving us the blocking patterns we either desire or don't. If you read up on Hadley cells @offerman you should find the answers you are looking for. Incidentally the rise in mean global temperatures will give rise to a 2 deg latitude rise in the AH, so essentially moving poleward very slowly, this brings more precipitation to the regions on the edges of the Azores high systems. What I want to know is if we are under the influence of High pressure over the UK for a prolonged period how would a SSW effect this pattern and how long would the effects take to show? Maybe a bit off topic for the MOD thread but thought I'd sneak it in here While it is relatively quiet

Fair point BA, as was mentioned in the thread earlier still 11 runs to go. I personally think the jet stream is being overhyped by the GFS, they have it ramping up big time from now to Sunday from the US eastern sea board across the Atlantic towards the uk and I believe they have a tendency to overdo it. the vorticity effect on the slider will, in part, be determined by the jets speed and track and that being the case, if it is being modelled too strongly then would the slider low meander eastward or stay on a south / south west track?

12z GFS ensemble mean for Sunday doesn't have the track as far south for the white stuff. Sorry guys n gals

12z GFS ensemble mean has the snow bang over that area I'm talking about.

For what its worth I think the GFS is overdoing the jetstream strength and thats causing the track of the slider to veer southward more on the 12z run. IMO the operational run is wrong and the track of the low and snow will be borders / central Scotland as high as Perthshire.

never noticed this before! Hahaha

Some current netatmo temps for Scotland, dosnt look cold enough for snow anywhere! tbf most of these things arn't calibrated correctly Well maybe Inverness but certainly not Aberdeen! Weird

Be as well posting a snow accumulation chart from ECM seeing as they are being used over on the MOD. For my Fife friends we will see some of the white stuff according to the latest run

My assumption based on his usual dialog being bias towards the USA (obviously as he is a yank) is that the "coldest temperatures over Europe" are at 10 hpa, and the downward propagation to the trop "suggests" favourable cold pattern for the USA. Thats how I read it anyway.

Unequivocal means leaving no doubt, unambiguous so of course there are signals there. All Ali is doing is stating the obvious. No rumour, and highly doubtful the reason IF doesn't post here anymore. Question for experienced posters. Do the models take strat data as an input for starting conditions for their various runs? i.e 500hpa + SLP charts. Could the model confusion post 120 be caused by variations in the strat? Thanks

Couple of GEFS ensembles to keep the coldies happy.....to be honest the ensembles don't look that bad, slack easterlies galore.

From what I have read regarding HIRLAM, it is highly respected along side ECM with regards high resolution for wind data. (If I can find the link I will share) watching the precip charts from HIRLAM over the past few months I'm not overly impressed tbh. Arpege high resolution seems to do OK, for what it is worth tonights charts from ARPEGE & HIRLAM some difference in regards to precip events country wide. Lets see what happens.....

Im just missing the twitter feed.... Hee Haw snaw here but wasnt expecting any TBH. HIRLAM has an interesting feature tonight around 20:00 across central scotland however.

For me it shows that from Monday onwards the main cluster of ensembles starts to trend below zero Deg C. This could indicate a potential Easterly for the south of Englanshire. The easterly will drag across cold air from the eastern block across the north sea towards the south of the UK bringing with it those cold temps.

Great website for live wind data for the north sea, access to most of the Oil rig platform weather data. Every one of those rigs in the firing line from very strong winds. Sorry mods off topic http://mmweather.net/page/maps

There you are

Svalbard for a sun holiday?

Ah ok igloo, wasn't aware of this thanks.

Gem not far away at + 144 looking very cold and that precip on the west coast moving east to hit the cold would be a pretty decent event.

Further to Jo's post if anybody would like to be an administrator for my Netatmo site drop me your twitter handle or email address and I will invite you. Similair data, maybe more graphs and has current temp and rain data that you can trend back a year on some. Cheers