bradymk

haha i know. Amazing when you see that chart, the pattern was outstanding. This is completely different to then so anyone expecting anything like 17th December 2010 is going to be upset. BUT the latest ECM run is an absolute great run and even if you dont see snow thursday, you shouldnt have a long wait, prolongs the cold the most and the best run yet going forward. Also for Thursday, coldest air is over Wales midday, but on euro4 there is no precipitation at this time. Uppers are -8c, dew points below freezing, that should be snow if the model is right and anything does fall from the sky. More runs needed, to see what happens with that precipitation in the south west. Less cold Friday, snow unlikely, before the coldest air yet comes back sunday with a straight northerly. PS. the wet bulb level (good for seeing if snow or not), is 300 metres for most of Wales on Thursday, dropping to 200 metres for a time. This is a bit marginal for snow but possible, in comparison, the wet bulb level for Sunday is 0 metres. Snow CAN fall below the wet bulb level if precipitation is heavy enough. Of course i am talking about low levels here, if you're on high ground, you should be good.

Trough disruption and energy going under....

http://www.netweather.tv/index.cgi?action=radar;sess= this and then click weather type on. The chart and uppers for that day The chart and uppers for Thursday, warmer uppers, more stable too.

If you're in West Wales (wish i was), sunday looks almost the perfect dangler setup, probably one of the best places to see snow on the weekend is the usual snowless pembrokeshire.

The NW wind direction would suggest the fetch over the irish sea is not enough yes and that it is shadowing the precipitation, hence no showers over Wales on euro4. However euro4 not always great at picking up showers plus December 2010 was a north west wind similar direction to thursdays but the air may not be as unstable as then.

Latest euro4 for +48, can see the precipitation over SW eng.

typical I'm in cardiff on the one weekend I want to be home in pembrokeshire!!

They are usually issued around 11:00 in the day, i expect tomorrow will be the day if they are going to issue anything for Wednesday night/thursday night. They expect most of the disruption northern england northwards which is why a warning already issued for there. Probably waiting until further runs from the high res models before issuing a warning further south.

That shortwave south of Greenland at 144 UKMO is on ECM 144 too. Shortwave drops southwards to our west at 168.

ahh yes i see, read it wrong at first, just letting people know when it is out rather than an update to the model itself, never mind, cheers

Anyone know what this tweet is about? Ryan Maue â€@RyanMaue 1m1 minute ago New European global model arrives in 15-20 minutes (1 pm EST) Good upgrades so far this afternoon with a potent northerly early next week on GFS. UKMO good too, but would like to see the +168 chart with the shortwave south of greenland at 144 which isn't there on the GFS.

We will know more when it comes into euro4 high res model range, later tonight/tomorrow morning.

Maybe not the end of the week woody, but the end of the weekend and start of new week looks much better, perhaps a good dangler setting up and everything points to supportive to snow too, especially monday, tuesday. Something to watch but still too far out for now. An upgrade so far from this afternoons runs.

The GFS weather type/snow risk/snow level charts are all just a bit of fun and almost always turn out to be inaccurate as the time comes closer, be that for increasing or decreasing chances of snow. Better to look at a combination of other charts such as wet bulb level, dew points and the upper temperatures. Uppers for early Thursday, -7/-8c across Wales (as a rare guide from this type of situation, -5/-6 uppers can be sufficient) The wet-bulb is the lowest temperature to which air can be cooled by evaporation, often important in determining whether it will rain or snow at or near the surface. For Thursday am, this down to below 200 metres for all of Wales also suggesting snowfall even to lower levels. Dew points are below freezing for all, also supporting snowfall to low levels. Thickness also supportive of snowfall,ideally you want it light blue or darker for a good chance of seeing snow. So don't get too hung up on snow chances end of the week yet. North and west Wales will most likely see the most precipitation and therefore the highest risk of snow. Thursday will come under high resolution euro4 tomorrow morning so we will have a better idea then. If you want to check out what 12z GFS has for these charts above, check here http://www.weatheronline.co.uk/cgi-bin/expertcharts?LANG=en&MENU=0000000000&CONT=ukuk&MODELL=gfs&MODELLTYP=1&BASE=201501261200&VAR=taup&HH=6&ARCHIV=0&ZOOM=1&PERIOD=&WMO=

Maybe, but many would argue the opposite and say for that our part of the world, global warming may lead to an increase of colder winters. This aside, colder winters do tend to come and go in patterns. The late 70's were cold winters but then the mid to late 80s were some of the mildest on record. It seems after 2009 we reentered a cold winter period but now possibly we are entering a milder period again. Who knows but global warming may actually cause an increase in colder winters and warmer summers for our latitude

I was inside and thought it was raining but come outside now and it's actually still bone dry here, hasn't rained or snowed so it may well of snowed here too if we had some of the main precipitation. Hopefully you'll have plenty more opportunities to to try the tyres over the next few weeks!

haha typical! Bloody urban heat island, although probably minimal in Cardiff, it is still probably making a difference as you say between rain/snow. Areas around cardiff slightly higher too which helps, plus the wind is from the south east and the city centre is closer to the estuary. May have to take a drive at lunch!Ps. It is not actually doing anything in cardiff mind, main precipitation looks slightly further west

Rain here in cardiff city centre at the moment. But doesn't look like much falling at all.

The reason why the radar shows precipitation when there is nothing falling from the sky is because of the air. The precipitation is only light and moving into very cold dry air and this is preventing the precipitation from actually reaching the ground as it evaporates before reaching ground level. You need heavier precipitation for the droplets to reach the ground when the precipitation is moving into a dry cold airmass like today. Ps. If I was around the Wrexham area, id be excited for tomorrow, looks like it will be a decent event for areas around there.

Attached is the 18z Euro 4 model for midnight tonight and it's predicted snowfall for the precipitation moving east over Ireland. The other image is the live radar image over Ireland. Many areas are seeing snow, more areas than shown were predicted snow. Maybe an encouraging sign, who knows. The front looks dead.

18z euro 4 showing good signal for snow in parts of the south east at 6am, could be a surprise for some.

yes precip coming in early morning, temperatures will rise with it though but ground will be frozen by then, so whether it is rain or snow that falls, ice likely a big issue. MO going with settling snow 200m+ so will have to wait and see.

GEM decides to just add to the uncertainty Ian F said earlier that some EC ENS members had us in a north westerly come friday, and that is what the UKMO +144 chart is now showing. Huge shift east at that timeframe though and probably just one of the many options possible for tuesday/wednesday.

You can see on the JMA, the further east and deeper the low The better the easterly feed as the troughing moves more into Europe and fills here and holds the ridge up better to the north east

GEM looks possibly good for SE Sunday night, been consistent with that low crossing the channel. Thoughts? Possible snow southern then south east counties, not sure The slider to the west looking good too PS. Just been sent some photos from family back home in haverfordwest pembrokeshire, (W Wales) where they had a remarkable hailstorm Tuesday night Look at the size of these