Feb 15-16 Possible Mixed Event.

[Cheeznado]

One of the biggest issues is how much precip falls before 18Z Monday. New GFS says not much. By later Monday the surface high is really booking offshore so when the heavier precip arrives the air mass is pretty stale. I have given up on frozen of consequence here, far NE GA still has a shot at some decent but not crippling ice, but then most turn to rain eventually

[franklin NCwx]

One of the biggest issues is how much precip falls before 18Z Monday. New GFS says not much. By later Monday the surface high is really booking offshore so when the heavier precip arrives the air mass is pretty stale. I have given up on frozen of consequence here, far NE GA still has a shot at some decent but not crippling ice, but then most turn to rain eventually

the most amazing thing is the difference between the models So close to an event.

Im talking amped cutter or weak Gfs like solutions.

[arandall]

Very very weak surface low over Athens ga. Snow to ice to rain for folks.

In addition to the main low? In theory a low in that position could hamper warmer air getting pulled in from the south by the main low, right?

[mackerel_sky]

the most amazing thing is the difference between the models So close to an event.

Im talking amped cutter or weak Gfs like solutions.

Shortwaves will be on shore today. Later runs should have full data ingest, for better or worse, more consistancy , hopefully

[superjames1992]

The 06z French Fries looks to have backed away from the warmer, more amped solution it had at 00z. We'll see what the 12z run shows in a couple hours.

I'd like to cash out with the last two RGEM runs, though.

[snowlover91]

Both the NAM 4km and RGEM line up well at hour 48 with HP placement and LP as well. Going with a blend of these two since they'll pick up better on small mesoscale features that will impact the track and strength of the LP as well as the HP positioning.

RGEM hour 48

4km NAM hour 48

[BullCityWx]

Interestingly, the GFS now has measurable precip falling at HKY as soon as 0z tomorrow night.

[BullCityWx]

if I am "hitting the soundings hard" you can make a case this thing kicks off earlier than most models anticipate. 

 

[snowlover91]

if I am "hitting the soundings hard" you can make a case this thing kicks off earlier than most models anticipate. 

 

hkysounding18z.jpg

RGEM has precip starting between 00z Sunday and 03z Monday for your area.

[Lookout]

Seems like less precip , while cold, and not as cold as models were showing a few days ago, is the theme! Today we are seeing the models kick out temps in upper 20s with dp's in the 20s!??

What happened to the 20's/single digit DPs? Air not as cold as thought, less precip, or heaviest falling Monday evening, high booking out faster, equals failed winter storm, for my area atleast and probably , alot more areas

What are you looking at? the nam/rgem are incredibly cold. Hell the rgem has temps in the upper teens in north carolina. rgem and nam.

 

 

One of the biggest issues is how much precip falls before 18Z Monday. New GFS says not much. By later Monday the surface high is really booking offshore so when the heavier precip arrives the air mass is pretty stale. I have given up on frozen of consequence here, far NE GA still has a shot at some decent but not crippling ice, but then most turn to rain eventually

I agree with the bolded. I'm going to make a long post in a while but biggest negative is precip or potentially lack thereof monday. If we have enough to come close to our wetbulbs, i can almost guarantee temps will never go above 32 for the usually prone areas. If however, there isn't enough it could be a problem. However, the degree of warming the gfs is showing upstream over the carolinas is patently absurd. all models show enough precip there falling into an airmass that is already in the low 20s with wetbulbs in the upper teens. Even if there is a break in the precip there in the afternoon, i think it's safe to say it's ludicrous to believe temps go from 18 to 20 to mid 30s 6 hours later.

 

as for the parent high, i wouldn't say it's irrelevant but since the cold is already in place and the initial  airmass is very cold, colder than usual in fact...that's it's less of an issue.  We have had quite a few icestorms or events where the high is progressive and/or has already moved out of place...Which means  what really matters is whether or not there is enough precip to get down to those wetbulb temps or  enough to counter solar insolation and waa. If there is enough, the cold pool would be extremely hard to dislodge or warm up in time.

 

But as you noted, the gfs is pretty light for the most part (save north carolina where they get a good bit by morning). If not for that fact, i would be almost 100% certain this is an all subfreezing event for the usual damming areas in northeast ga. I'm already there really for the carolinas.

[superjames1992]

The 12z GGEM is rolling out now. It looks pretty similar to past runs, though maybe a little further north (judging by the awful Meteociel.fr maps). Matches up well with the RGEM and NAM with a hit from the WAA precip. Big daddy for CADland.

[snowlover91]

I agree with the bolded. I'm going to make a long post in a while but biggest negative is precip or potentially lack thereof monday. If we have enough to come close to our wetbulbs, i can almost guarantee temps will never go above 32 for the usually prone areas. If however, there isn't enough it could be a problem. However, the degree of warming the gfs is showing upstream over the carolinas is patently absurd. all models show enough precip there falling into an airmass that is already in the low 20s with wetbulbs in the upper teens. Even if there is a break in the precip there in the afternoon, i think it's safe to say it's ludicrous to believe temps go from 18 to 20 to mid 30s 6 hours later.

 

as for the parent high, i wouldn't say it's irrelevant but since the cold is already in place and the initial  airmass is very cold, colder than usual in fact...that's it's less of an issue.  We have had quite a few icestorms or events where the high is progressive and/or has already moved out of place...Which means  what really matters is whether or not there is enough precip to get down to those wetbulb temps or  enough to counter solar insolation and waa. If there is enough, the cold pool would be extremely hard to dislodge or warm up in time.

 

But as you noted, the gfs is pretty light for the most part (save north carolina where they get a good bit by morning). If not for that fact, i would be almost 100% certain this is an all subfreezing event for the usual damming areas in northeast ga. I'm already there really for the carolinas.

Excellent post! The RGEM and NAM seem to have a better onset of precip in the CAD regions of NC and parts of SC also. If this indeed occurs before 12z on Monday it will lock the cold air in much better than models indicate. More of them are trending towards a weaker and further south LP also, the only two still amped are Euro and UK. I expect the Uk at least to go closer to what GFS and CMC show. Inside 48 hours the RGEM is top model for precip and transition zones so I would give that one extra weight at this range. It's performed extremely well for the past few threats here in NC.

[jburns]

But as you noted, the gfs is pretty light for the most part (save north carolina where they get a good bit by morning). If not for that fact, i would be almost 100% certain this is an all subfreezing event for the usual damming areas in northeast ga. I'm already there really for the carolinas.

NWS Raleigh has me all rain from 4pm Monday.

[Snowless in Carrollton]

I just don't see how NE GA stays below freezing all day while ATL is in the 50s on Monday.

[Lookout]

NWS Raleigh has me all rain from 4pm Monday.

how does your location normally do in cad situations? In particular those that are more focused toward the foothills?

[jburns]

how does your location normally do in cad situations? In particular those that are more focused toward the foothills?

It hangs on pretty good here. I'm just a few miles SW of Greensboro.

 

Washington's Birthday

Snow, freezing rain, and sleet likely before 3pm, then rain or freezing rain likely between 3pm and 4pm, then rain likely after 4pm. Cloudy, with a high near 34. East wind 3 to 7 mph. Chance of precipitation is 70%. New snow and sleet accumulation of 1 to 2 inches possible.

[JoshM]

One thing that bodes well for early precip is this coastal low the 4k NAM is showing. It gets precip in here early Monday and helps lock in the in-situ wedge. IMO, that's a big part of keeping our cold locked.

 

EDIT: Not even a low really, more of a moisture fetch.

[SN_Lover]

Parties over for those who still stuck around. CMC moved north and joined its friends. 

[burrel2]

I just don't see how NE GA stays below freezing all day while ATL is in the 50s on Monday.

What makes you think Atlanta sees 50 degree's on Monday? I'll be surprised if they break 40 on Monday.

[superjames1992]

Parties over for those who still stuck around. CMC moved north and joined its friends.

Somewhat, yeah, but it's still a major storm somewhat in line with the NAM/RGEM. It is still quite cold for the prime CAD regions of NC, upstate SC, and NE GA. Starts out temps around 20 here, which would take awhile to dislodge.

I have to think MBY and a lot of the best CAD regions, at least, will get warning criteria something at this point, even if it gets washed away by rain later.

[BIG FROSTY]

Parties over for those who still stuck around. CMC moved north and joined its friends. 

Ok see you next storm! It did warm some not as much Ice shown! Still looks like a wintry mess for a good bit of the storm for CAD areas. 

 

[Lookout]

I just don't see how NE GA stays below freezing all day while ATL is in the 50s on Monday.

that's because they probably won't be at 50. If there is enough precip monday to maintain the cold pool, temps will be a far cry from that. Regardless of actual freezing temps, the overall handling of temps period is just awful..especially the gfs. .the 12z nam for example is as much as 12 degrees colder at the same time on the 12z run vs the 06z run for much of north ga..taking areas like atlanta from 50 to 38 or 39. Indeed the nam has temps staying subfreezing now in the far northeast corner.

[MichaelJ]

This close to the event,  I still think I would stick with the NAM and it's track and temp depictions. Precip wise it is probably wise to cut it back from what the NAM shows. I would not rely much on the GFS or CMC or RGEM at this point

[PackGrad05]

Based on the models I've seen this was never going to be a huge snowstorm for anyone south of 40.  Wintry mix at the beginning will create travel issues all across NC...but by mid-day, the rain will wash stuff away and it'll be a flood potential through Tuesday.

[Blue_Ridge_Escarpment]

Ok see you next storm! It did warm some not as much Ice shown! Still looks like a wintry mess for a good bit of the storm for CAD areas.

3-5 inches of snow followed by .85 of freezing rain per the Canadian here. Hope it's dead wrong.

[franklin NCwx]

Ukmet has a 998 over Spartanburg.

[snowlover91]

This close to the event, I still think I would stick with the NAM and it's track and temp depictions. Precip wise it is probably wise to cut it back from what the NAM shows. I would not rely much on the GFS or CMC or RGEM at this point

RGEM is better inside 48 hours than NAM most of the time, at least this year for my area the RGEM has been much better. Either way the RGEM and NAM are much colder than other models and are picking up the CAD better.

[oconeexman]

I just don't see how NE GA stays below freezing all day while ATL is in the 50s on Monday.

Have seen it many times. A true wedge is a weather wonder.

[Bsudweather]

Bingo. Cmc has its own biases perfect for weenies. With the HP sliding out so fast I doubt we trend to an all snow solution, even in CAD areas. The snow at onset should be fun, though. Glass half full?

Was there ever many on here thinking this was gonna be an all snow event? If so they crazy 95% of this board that has common sense knows this is a thump of snow to Ice storm to backside rain. I'm speaking of the CAD areas

[BIG FROSTY]

3-5 inches of snow followed by .85 of freezing rain per the Canadian here. Hope it's dead wrong.

Yup! It is amazing how consistent this model has been  for the last few days, even though it may be consistently wrong? it has stayed the course for the most part.. So I don't see how you just toss it when it's been the most consistent? JMO