It's right on the edge. If the warm layer is 0 to +1C, flakes will partial melt then refreeze lower down, staying as snow. If warm layer is +1 to +3C, more melting will occur and then it would refreeze lower down as sleet
Yep, GFS was delayed about a day and a half compared to the previous run with dropping the TPV down...fine with that as long as it actually drops down at some point lol...that's the bigger question in my mind
It's a tough forecast for sure. burrell and others have been on this, but if it will come in hot and heavy on the leading edge of the frontogenesis band that is propagating north, it will want to drop the sfc temps to 33-34 for some wet snow accumulations while the sun is down (which helps). 18z GFS sounding in the upstate at 10pm
Yeah it's a different ballgame if we can just get the cold TPV to drop down. Large area of -20 deg C temperatures at 850mb (pink contour) in bottom right image...with -30 deg C contour as well (purple)...on GFS at day 6-7.
Was going to say the same thing lol but want to see if the Euro follows up last night’s run. In fairness, the UKMet doesn’t go out into the long range as you know
I just want to see the cold vortex in Canada drop down. Euro/EPS from last night never dropped it down because it loses the NE PAC ridging, so that’s the close the curtains scenario. UKMet and GFS/GEFS look similar at 144 today where they both want to swing it down out of Canada.
Happy hour GFS has a light snow storm on day 10 and major wintry mix storm on day 12. Yeah I know that's crazy being so far out, but whatever. Honestly, I can't recall ever seeing a model run that held good high pressure in place for so long like this one.
The wave dampens out, but it has light snow across the south and into the Carolinas. GFS actually has a really good looking pattern (lol) after that high drops down as it just holds the cold high over the upper Midwest with an active southern stream
Happy hour GFS may try to deliver actually, let's see. It's later of course. The window simply isn't going to open, obviously, until that TPV in Canada (and sfc high) drops down into the conus. Wave in the 4 corners at hr216 with lots of cold out front
CMC is crazy looking at the end...it has the entire coast from Brownsville to south of New Orleans below freezing with warm advection precip from the gulf being thrown up into the cold air (wintry mix)
12z GFS/CMC/UKMet all have that look of late week rain storm, then cold (UKMet only out to 144 shows the rainstorm setup, don't know afterward)...let's see what the Ensembles and Euro show
Yeah, long way out, but at the moment, the setup would favor modest surface low pressure strength, so naturally, weak to moderate winds instead of heavy