December 8-10, 2018 Winter Storm

[Brick Tamland]

13 minutes ago, wxdawg10 said:

looks like Allan Huffman is going all in on this.  RAH still on an island

What did he say?

[PackWxMan]

This is an ice storm. Not a snow storm.

[tarheelwx]

06 NAM had precip barely getting into GSO by 1 pm Sunday.  Will be interesting to see if it speeds things up a bit as most other models are a good 6 hours faster. 

TW

[magpiemaniac]

RAH’s uncertainty line has moved west overnight.

4:00 PM graphic on Wednesday

5:00 AM graphic on Thursday

[BretWx]

52 minutes ago, Orangeburgwx said:

Heh, I just vented to the NWS CAE office in a private messege on Facebook for not acknowledging the threat as it stands.

Yikes.... 

[tarheelwx]

3 minutes ago, Brick Tamland said:

What did he say?

Allan said:

Major winter storm with heaviest wintry precip over western/central NC, s VA, n SC, ne GA, with epicenter for heaviest snows in NC mountains, foothills/western-central piedmont.  Will post first call map later today.

TW

[27596WXNUT]

6 minutes ago, Brick Tamland said:

What did he say?

@Brick Tamland somebody asked him about accumulations for Raleigh in response to the Tweet Tarheel posted and his response was “significant”.  That what I’m guessing the other poster is referring to.  

[PackWxMan]

8 minutes ago, magpiemaniac said:

RAH’s uncertainty line has moved west overnight.

4:00 PM graphic on Wednesday

5:00 AM graphic on Thursday

Let’s not overreact here

[Brick Tamland]

4 minutes ago, magpiemaniac said:

RAH’s uncertainty line has moved west overnight.

4:00 PM graphic on Wednesday

5:00 AM graphic on Thursday

Yet, all the models went farther east with snow. I would really like to know why they think it will be different.

[magpiemaniac]

1 minute ago, PackWxMan said:

Let’s not overreact here

Not sure how you took that as an overreaction.  Just pointing out RAH observations folks might have missed overnight.

[BullCityWx]

1 hour ago, Poimen said:

One disturbing thing is that the GFS soundings are consistently showing less than full saturation in the snow growth region early Sunday morning, which coincides with the heaviest precip and coldest portion of the storm through the column. I'm not sure what to make of that, but I'd like to see full saturation up there. 

Also slightly concerned about that.

[BullCityWx]

KUCHERA Ratio maps on PivotalWeather showing 10:1 ratios on the NAM at 84. 

[Orangeburgwx]

Something has me baffled...

 

I'm trying to figure out how one plume of the GEFS came up with 7.17" QDF and 19" of snow for CAE... I get the ensembles are variables, but that run had to be smoking crack.

[PackWxMan]

I think I speak for the wx gods when I say, CAE is frz rain and sleet at best. No snow. 

[BullCityWx]

Looks like steady as she goes on the off hour euro. 

[WxJordan]

The models still show a major and historic winter storm for parts of the Carolinas. The rain/snow line is still in question, and will be for a while, but it appears north of I-85 will see major accumulations. The limiting factor could be a warm nose, which changes the snow to sleet across parts of the piedmont and foothills. Mountains will more than likely remain snow for most of the storm.

[BullCityWx]

Just now, PackWxMan said:

I think I speak for the wx gods when I say, CAE is frz rain and sleet at best. No snow. 

Agreed. I'm warning my Cola friends that this could be a lights go out ice event. 

[burrel2]

NWS GSP update... too low on the ice accumulations, imo.

[jjwxman]

28 minutes ago, magpiemaniac said:

RAH’s uncertainty line has moved west overnight.

4:00 PM graphic on Wednesday

5:00 AM graphic on Thursday

 

 

19 minutes ago, PackWxMan said:

Let’s not overreact here

This is a very complex storm system and many players are involved as we all know. When there are uncertainties involved, RAH always errs heavily on the conservative side of caution.   With that said, I think that if the models hold through 12z today or 00z Friday you will see them change there wording to a more serious tone.  RAH does a great job, they will jump on board soon. 

[Rankin5150]

Here is a zone forecast from GSP for Gaston County. You can see where they show mixing with ZR during a time when the heaviest precip is moving through on Sunday. It will be flipping back and forth, so this would have a huge effect on totals. Also, there will be mixing on and off throughout. I am also hoping the models are not trending with the HP being weaker, like I have seen on the past 2 runs. Plenty of time, but I thought I would throw that out there. I guess beggars cannot be choosers though. This is EARLY December. This is awesome, based on our climo: 

Saturday Night

Cloudy. A chance of snow in the evening, then snow likely after midnight. Heavy snow accumulation possible. Breezy with lows around 30. Chance of snow 70 percent.

Sunday

Freezing rain. Snow. Additional heavy snow accumulation. Brisk. Near steady temperatures in the lower 30s. Chance of precipitation 90 percent.

Sunday Night

Snow. Sleet likely after midnight. Additional moderate snow accumulation. Near steady temperatures in the lower 30s. Chance of precipitation 90 percent.

Monday

Sleet likely in the morning. Snow and rain likely. Additional light snow accumulation possible. Highs in the mid 30s. Chance of precipitation 70 percent.

Monday Night

Mostly cloudy. A chance of snow or rain in the evening, then a chance of snow after midnight. Lows in the upper 20s. Chance of precipitation 40 percent

[burgertime]

Unless we see some drastic changes we just have trust what conventional wisdom tells us in these situations. Obviously north of I-40 is in the best spot for all snow, but no need to do any cliff jumping. Again even if you cut these totals in half that still a big snowstorm for EARLY december. 

[Rainforrest]

2 minutes ago, burrel2 said:

NWS GSP update... too low on the ice accumulations, imo.

Looks about right for my location. Hoping for more though. 

[burrel2]

One thing I'm concerned about for the upstate storm potential. I've noticed over the years, while CAD is always underdone on the models, an arriving CAD is usually a few hours later than models show. They usually arrive later, but hold out longer.

In the upstate, we are relying on the CAD arriving during precip late Saturday night. If it builds in a few hours later than expected, we will waste all the front side precip to rain. Something to keep an eye on.

I do fully expect the entire upstate to drop in to the upper 20's when the CAD entrenches though, and seemingly we still have quite a bit of precip left to go through Sunday evening. So even without the front end thump it should be significant. (I will say that the coverage of precip is more unpredictable after the initial band goes through, so it's possible we don't get the modelled qpf after Sunday morning). But even if we just get a few tenths it would be bad from an impact stand point with temps in the upper 20's.

For the upstate, I think the later precip arrives the better as it gives more time for CAD to build in.  If we get in on the finger of precip streaking out ahead of the storm early Saturday... probably not good for us. (But great for franklinweather since he'll be snow then).

[Amos83]

3 minutes ago, burrel2 said:

NWS GSP update... too low on the ice accumulations, imo.

interesting, based off this graphic looks like their thinking is that the it is basically all snow from around UNCC and points north and west

[burgertime]

Just now, Rankin5150 said:

Here is a zone forecast from GSP for Gaston County. You can see where they show mixing with ZR during a time when the heaviest precip is moving through on Sunday. It will be flipping back and forth, so this would have a huge effect on totals. Also, there will be mixing on and off throughout. I am also hoping the models are not trending with the HP being weaker, like I have seen on the past 2 runs. Plenty of time, but I thought I would throw that out there. I guess beggars cannot be choosers though. This is EARLY December. This is awesome, based on our climo: 

Saturday Night

Cloudy. A chance of snow in the evening, then snow likely after midnight. Heavy snow accumulation possible. Breezy with lows around 30. Chance of snow 70 percent.

Sunday

Freezing rain. Snow. Additional heavy snow accumulation. Brisk. Near steady temperatures in the lower 30s. Chance of precipitation 90 percent.

Sunday Night

Snow. Sleet likely after midnight. Additional moderate snow accumulation. Near steady temperatures in the lower 30s. Chance of precipitation 90 percent.

Monday

Sleet likely in the morning. Snow and rain likely. Additional light snow accumulation possible. Highs in the mid 30s. Chance of precipitation 70 percent.

Monday Night

Mostly cloudy. A chance of snow or rain in the evening, then a chance of snow after midnight. Lows in the upper 20s. Chance of precipitation 40 percent

Fixed that for you

[mackerel_sky]

Love waking up to 3 pages of new posts and 2 3/4 of the pages , are AFDs and some of the same ones 3-4 times! 

[Poimen]

GEFS 6Z exceeds 2" qpf up to the Triad. It's good to see those beefy totals continue. It's crazy because normally we're talking about .25-.75 qpf. This one factor makes this event far different from most others in recent memory. 

[Rainforrest]

1 minute ago, burrel2 said:

One thing I'm concerned about for the upstate storm potential. I've noticed over the years, while CAD is always underdone on the models, an arriving CAD is usually a few hours later than models show. They usually arrive later, but hold out longer.

In the upstate, we are relying on the CAD arriving during precip late Saturday night. If it builds in a few hours later than expected, we will waste all the front side precip to rain. Something to keep an eye on.

I do fully expect the entire upstate to drop in to the upper 20's when the CAD entrenches though, and seemingly we still have quite a bit of precip left to go through Sunday evening. So even without the front end thump it should be significant. (I will say that the coverage of precip is more unpredictable after the initial band goes through, so it's possible we don't get the modelled qpf after Sunday morning). But even if we just get a few tenths it would be bad from an impact stand point with temps in the upper 20's.

Hey Burrell you gonna make the trip up 178 to the in laws place?

[frazdaddy]

3 minutes ago, burgertime said:

Unless we see some drastic changes we just have trust what conventional wisdom tells us in these situations. Obviously north of I-40 is in the best spot for all snow, but no need to do any cliff jumping. Again even if you cut these totals in half that is still a big snowstorm for EARLY december. 

You can remove the word big and still make headlines with that statement.

[mackerel_sky]

2 minutes ago, burrel2 said:

One thing I'm concerned about for the upstate storm potential. I've noticed over the years, while CAD is always underdone on the models, an arriving CAD is usually a few hours later than models show. They usually arrive later, but hold out longer.

In the upstate, we are relying on the CAD arriving during precip late Saturday night. If it builds in a few hours later than expected, we will waste all the front side precip to rain. Something to keep an eye on.

I do fully expect the entire upstate to drop in to the upper 20's when the CAD entrenches though, and seemingly we still have quite a bit of precip left to go through Sunday evening. So even without the front end thump it should be significant. (I will say that the coverage of precip is more unpredictable after the initial band goes through, so it's possible we don't get the modelled qpf after Sunday morning). But even if we just get a few tenths it would be bad from an impact stand point with temps in the upper 20's.

Yeah, you are 1000% correct! Seen enough storms to also be leery of the highs on Friday, as we warm ahead of the front! Forecast high of 53 here, can easily see getting to 56-57 degrees! Then precip comes in early Saturday, before CAD sets up!