pdiddy

Spells of snow are likely to continue in some areas overnight. The snow will tend to become lighter and patchier later in the night, but may continue in some places during Wednesday morning. Most of the snow will be in areas above 100-200 m with accumulations of 2-5 cm are expected above around 150 m. Meanwhile, close to 10 cm could fall above 300 m over southern Scotland. Icy stretches are also possible for some, mainly over northern parts of the warning area. just changed the yellow warning 10 mins ago for Edinburgh to include the above... after-timers!!

interesting that the forecast didn't really call out snow tonight... let's hope they extend the MetO warning area to more of Scotland later!

settling on the grass in South Edinburgh now

Even within Edinburgh the conditions can vary considerably. The last event was mainly freezing rain/slushy ice for me, but a mile up Comiston Road and there was 3 inches of snow. I rather suspect a similar outcome Weds/Thurs, even though the BBC has it more like snow on their forecast.

Quite a range of options available for Zonal winds!

Off topic, but be careful when punting... Some bookies use different sites to get their evidence (mainly football grounds or airports). Betfair refused to pay out 2 years ago for Edinburgh when there was sleet and snow at 11.30pm because it was not recorded by the met office.

Christmas Eve view!

Woken up by Thundersnow! that's a first for me!

To be fair, that's just an update from him, rather than his winter forecast; more of a "based on what the models are saying at this point"

Not an outlier for Aberdeen,so possibly a "scaling" issue for Norway! That said, perhaps the Scandi high being shown on the 12z meant very localised conditions!

Split of options shows very well in the Nuuk ensembles...

Not sure I can recall such a tightly packed bunch across the GFS ens at this time of year before. Nothing looking like breaching the -10 line either... At least the signal is drier for the last 10 days of the month (at this stage!)

brave call that on the first!

The mean in FI is fairly meaningless though as it simply blends all scenarios. I'm more positive in the mid to longer term about the lack of PV in Greenland and Canada.

Must admit I don't understand some of the posts here. Doesn't look zonal to me and the pattern remains of great interest. Certainly wet for the foreseeable as lows remain slow moving with the potential for more rain. Heights over Scandi remain and this is where I am focusing attention.

i will be very (and pleasantly) surprised if Edinburgh gets much snow in this set up.

I think the cold will stay another day, E17.

http://www.meteociel.fr/cartes_obs/gens_display.php?ext=1&lat=55.9533&lon=-3.1883&ville=Londres I'm not in any pain with this at all.

Just waiting to see what happens to the jet next. How much energy going in each direction as it splits in the Atlantic...

The GSFP has been reasonably consistent in showing colder conditions from mid-month, which is still 2 weeks away. Had the MetO been absolutely spot in in their forecasts previously, I might pay more attention. As it is, mid-month is not without interest and those writing off cold until Feb are being a little hasty IMO.

Happy to be corrected if you have evidence to support, but not true according to the Met Office: What impact does this have on the UK? We normally expect our weather to come in from the west - with a flow of relatively mild air coming in off the Atlantic. When an SSW brings easterly winds this tends to alter our weather patterns slightly, weakening areas of low pressure and moving our jet stream further south. This leads to high pressure over the North Atlantic, 'blocking' that flow of mild Atlantic air and dragging in cold air from the continent to the east. Exactly how cold it might be depends on the details of where the air comes from. SSWs don't always result in this outcome - but a cold snap follows more often than not, so the SSW greatly increases the risk of wintry weather. https://www.metoffice.gov.uk/learning/wind/sudden-stratospheric-warming

GEFs showing milder uppers next week or so with a trend to colder on/around the 7th: http://www.meteociel.fr/modeles/gefs_table.php?ext=1&x=306&y=141&ville=Londres I find this table format helpful to assess ensembles...

Meanwhile, back at the GFS Ranch and it's all change again on the 6z. Problem seems to be how to deal with the cold plunge in to the US and downstream impacts on the jet to me... http://www.meteociel.fr/modeles/gfse_cartes.php?ech=6&code=0&mode=1&carte=1 http://www.meteociel.fr/modeles/gfse_cartes.php?ech=6&code=0&mode=5&carte=1

18z going for an Easterly here?

I can't agree with those bemoaning the lack of fantasy output showing cold. It was always most likely that December would finish with a HP close by especially given the signal for precipitation: Thereafter, chance of cold increases because of the strat situation. It's not nailed on by any means but the chance nevertheless increases. We also know from experience how hard the models find it in this scenario. I'm sure someone can post the verification stats from last Feb to prove my point. I have the 10th of Jan in mind for a change to cold, based on a week to ten days after the split/displacement, with the former seemingly most likely. Hence I'm expecting to see some ensembles starting to show cold (and we have seen these for a few days now) and over time expect to see more of this.