bradymk

Quick question to anyone, does anyone know when the new hi-res GEFS is going to be made live to go along with the new GFS?

Plenty of snow chances next week even if Wednesday's slider low doesn't end up in a favourable place. Friday January 18th 2013 was when we had widespread snowfall from a slider low in Wales. If you want to know what to look for in the charts for this low to be more favourable then you want the low pressure to be more elongated and further south and west, rather than an oval shape. This was from ECM yesterday You can see the oval shape to the low here, no snow likely for most of Wales This is the 18th January 2013 You can see then the low to the west is more negatively tilted, the isobars face SE-NW, rather than NE-SW like they usually would on a low pressure coming in from the atlantic. This means that we get a south easterly continental flow instead of south westerly flow, which means much colder air and on this case gave a dumping to many. There was a red warning in the valleys if you can remember. This low aside that Steve mentioned in the model thread, what happens after that looks likely to bring snow chances to all anyway, so we will just have to wait and see. The low for next week tues/wed already better on the 18z GFS with a wedge of heights to the north. hopefully more improvements to come than downgrades.

ECM 168 chart from yesterday ECM 144 chart from today Low further west and more trough disruption, and we all know it will probably end up even further west by +0

yes, think colder air starting to get entrenched now again as temps had risen from earlier but should start to drop away now until daylight, icy start probably whether you have snow or not â„ï¸ Are you on higher ground?

Sleet, wet snow, now light rain again in Cardiff, wet not white. But temperatures have actually risen last hour or two, but forecast to drop again now so we will see, plenty of shower activity heading this way.

yes same, temperatures on the rise at the moment but temperatures will be much lower too 3-6am 0c/1c for many according to latest run. Wish I could stay up and find out.There's a very heavy shower south of swansea at the moment, looks like heading for here so may stay up for that one.

Euro 4 18z showing the current lull we are in with showers but it still shows heavy precipitation early hours of the morning. These showers can be seen now to the west of wales that are building up nicely. If you're up early for work, you will probably see some falling snow at least.

If you're on the south wales coast, the showers to the south west of Pembrokeshire should continue to develop as they moves eastwards, look the next main ones, bit of a lull until then but they could be good!! Hope the temperature continues to drop... The shower i am on about, if it carries on same trajectory, probably around 00:00 cardiff area.

ye back up to 3c here too. Might have to wait until the lower temperatures look to kick in after midnight and towards early morning. Big area of precip showing between 3-6am for South East Wales so we will see what 18z euro4 shows.

Showers coming more west'ly now than earlier. Started again in cardiff. Rain/Hail still.

yes exactly, doesn't seem to be melting either, bring on the next shower

1.6c after that shower brrrrrr, everything white, hopefully the hail stays on the ground, may help with any potential settling snow later.

Big shower in cardiff. Mainly hail, everything white from it though, should have dragged the temp down that little bit further for later showers

Temperatures forecast to be lowest early hours. Still think for where i am, looking at euro4, between 03:00 and 06:00 looks the best time for snow in lower levels of south east Wales. Big lightning flash as i type.

temps starting to fall more quickly, down to 2.4c here in centre of Cardiff now, keep going, next heavy shower hopefully more wintry than the last!

Temperature 3.5c here now. Just need more of a drop. Rain has turned more sleety but probably going to have to wait for the temperatures to drop further (expected) before falling snow here.

4c in Cardiff still, need more of a drop, temperature should drop in showers too mind. But may have to wait a bit longer until these showers fall as snow, in the middle of Cardiff anyway.

If you're in cardiff area, 19:45/19:50 looks the time for a decent shower, hopefully temp and dew point has dropped enough for it to be white not wet!!

bit annoying, sat in Cardiff as in uni at the moment whereas at home (where it rarely ever snows), i am having texts and videos from family in Pembrokeshire where it is currently thundersnow!! typical, but the best time for precipitation in Cardiff looks favoured to be 3am and later when showers look like merging for a longer spell of precipitation for SE Wales and SW Eng. Plenty of come before then mind.

Metoffice snow/ice warning just issued for most of Wales. Accumulations likely only 100+ metres however

Think some maybe underestimating the depth of just how cold this incoming PM air could be. a PM west/north west flow rarely delivers for snow unless you are on higher ground but I think the period Tuesday/ tues night may deliver snow for a lot. Dew points below freezing for all of wales by the evening with low uppers and thickness too. It could all change and it is quite marginal but good chance of seeing some falling snow Tuesday night and also Thursday night/Friday. It is not the cold setup we all want but it could deliver some falling snow at least for a time. Keep an eye, met office issuing any warnings tomorrow.

impressive!! Shows why the clusters are generally the best tool to use most of the time and also why the ECM is still the number one model.

GFS parallel keeping it settled and cold with surface cold past the new year with a new ridge building in. Wonder if we can hold onto the high into Jan until we see further possibilities due to the start further into Jan? Personally much rather the MLB over us than a cool cyclonic pattern. Not sure the high will shift as quickly as the models shows as it comes closer to the timeframe but we'll see. ECM mean for days 11-15 isn't great though.

Just a last on the model data issue. "ECMWF DATA 24/12 18Z = 177831 total obs. ECMWF DATA 25/12 12z = 49240 total obs." This should clear up the topic, whether it vastly affects the runs I do not know, but clearly a lot less data on today's 12z compared to yesterday.

http://old.ecmwf.int/products/forecasts/d/charts/monitoring/coverage/dcover!aircraft!06!pop!od!mixed!w_coverage!latest!/ take a look at this, much less observations today but not sure if it is enough to cause a big difference for the run.