That's nuts Roman - share some of that with us
08Z Update 12th Feb
Subtle changes today, the European vortex which has dominated the headlines over the past day or so has sunk south into the Med (bringing snow to much of France incl the Riviera) and is now producing convection over the Med. The cold pool of air (sub 516dam) has now warmed out somewhat and also slid away towards the SE, although the Upper low and inverted omega block persists over much of Europe.
The upper blocking high has re-orientated overnight and over the next 48hrs will slip slowly NW'wards as developments push it towards Greenland (both warm advection to the west and cold advection west of Svalbard)
A weak thermal zone containing a more maritime airmass has sunk around the high over the last 24hrs and is now covering the UK except the far SE, Outbreaks of rain,sleet still affecting the SE, bits of Snow above 200m, but WBFLs behind climb to around 500-600m meaning that Snow is unlikely from the showers coming into Eastern England exceppt over the Pennines and perhaps the higher parts of the N Yorks Moors.
Sunny this morning in the SW, parts of Wales and N England, but a lot of cloud elsewhere. Clear areas likely to go into Fog tonight - esp towards the north where gradients fall out.
This evening and tonight another shortwave comes SSW from Denmark and the flow across the South veers somewhat and becomes less maritime. 850mb temps and WBFLs fall away again, with negative WBPTs coming back into the SE by 00Z and spreading west across other Southern parts overnight so that a cold end to the night is likely. Into the Weekend and we alsmost have a repeat with less cold trying to come down from the north (more Atlantic Maritime influence and the colder air across the south. Eventually the less cold air wins, but again light rain, sleet and patchy snow comes south across parts leading to a cold and grey weekend for some whilst others see more in the way of sunshine. The NAE is considerably faster with the higher WBPT coming south, the GFS is slower along with the UKMO GM ans the High Res ECM delays until sunday the less cold air moving south and actually re-introduces snow showers to eastern Kent for a time tomorrow. We will see.
Into next week and there is considerable differences in the detail in an increasingly cyclonic pattern across the UK. A Major trough extends SW from the Norwegian Sea as the high withdraws NW towards Greenland and the Davis Straight. The extent and position of the trough and assoc surface depression is however not in agreement between modells. There is more agreement for Monday into Tues as an occluding from comes southeast perhaps turning to snow ahead of it and behind it as warmer air is squeezed out, though this remains highly uncertain. The 00Z Models today having less of a snow signal than some of their predessors. Speed and orientation of the band as it comes SE questionable even at this stage - and needs to be firmed up over the weekend.
Beyond that the models are not in agreement with the postiioning of the trough and low, and there is inter model and intra model disagreement. The GFS has however somewhat consistently preferred the Cog of the low to end up in a more easterly location that the UKMO GM or ECMWF, therefore maintaining a somewhat colder theme across the UK. The ECMWF and UKMO prefer to keep the Cog of the low towards the west with higher WBPT and less in the way of cold air except across the more northern areas over highground. A number of GFS ensembles also keep the low centre further west, hence the weight of evidence suggests the ECM/UKM solution gains most support with the GFS colder scenario maintained as a lower prob solution at this stage - but its all subject to change. The ECM for example had more cold air around on its 12Z Run last night than its 00Z sol today.
The far south and SW look relatively less cold anyway in all solutions.
Paul Blight
UKww Manager - Education/Warnings
Associate Fellow Royal Meteorological Society
