December 8-10, 2018 Winter Storm

[wxtylerb]

1 minute ago, ILMRoss said:

Good lord RNK went low on the northern edge of totals


.

I noticed that, too! RLX very low! All models show at least 3" for Beckley up to 8"

[insipidlight]

Hm any reason for this?

[broken024]

Nam 3k is damn close to all rain for north union...

[olafminesaw]

RAH still going with all snow during the daytime Sunday. Seems pretty unlikely at this point.

[JoshWeather]

10 minutes ago, broken024 said:

Looks like northern union county might end up with just cold rain. Happens every time.

Lets hope so.  Anything but zr

[GunBlade]

19z HRRR 

[eyewall]

[burgertime]

Just now, eyewall said:

 

 

 

I think that map looks pretty good Jeremy 

[phil882]

12 hours ago, burgertime said:

Nailbiter as always because that tends to be an on the ground issue. We need @phil882 on the case! 

Ask and you shall receive!

Haven't been here in a while, but I wouldn’t miss a chance to check in with my old friends here. I’m out now on the west coast in a location (Monterey, CA) that never gets snow so now I get to live vicariously through you all.

To keep things on topic, one thing I’d lookout for is the front end precipitation rates (now-midnight). Have a feeling those in the WNC mountains will over preform with snow accumulation in the early going for this system, as the frontogenesis on the front end band is probably being a bit underforecasted given the impressive 40-45 dBz band seen on radar upstream.

For upstate SC, it will depend if the precip rates get high enough to bring the entire 800-sfc column to isothermal. We still have a ways to go for those still in the 40F range, but there is already plenty of mixing for those in the 35-37F range, so once the stronger band moves in, we should see most of the northern upstate (North of I-85) flip over to wet snow before the warm nose comes in.

[WidreMann]

2 minutes ago, eyewall said:

Pretty bold for the Triangle. We will fight mixing and marginal surface temps.

[burgertime]

Here is the HRR snow map... 

 

 

[lilj4425]

Nice to see you Phil. Really enjoy your insight as always.  

[Lookout]

9 minutes ago, broken024 said:

Nam 3k is damn close to all rain for north union...

I'll be honest, i'm having issues with the  3km nam. For starters, it's too warm at the surface. Second, i find it next to impossible to believe there won't be more sleet than it shows over northeast ga where it essentially has none. Never mind it is warmer than even the hrrr at the surface.   Third, it seems too warm aloft compared to the hrrr. Here is the 12z 3km nam 6 hour 850mb temp vs the 0z analyzed hrrr at 18z. So imho, i'd be cautious about it right now imo. 

The hrrr has done well in the past few winter storms here in ga so i'd put more weight on it right now. 

[Steven_1974]

Where is it we find the graphics that show what models like the NAM puts out per location like RDU over a given timeframe? Where it shows how much is Snow, Sleet or Freezing rain. I can't seem to locate it anywhere.

 

Something like this is what I'm talking about:

 

[packfan98]

Just now, burgertime said:

Here is the HRR snow map... 

 

 

Matches pretty well with the Kuchera map from Pivotal:

[burgertime]

1 minute ago, phil882 said:

Ask and you shall receive!

Haven't been here in a while, but I wouldn’t miss a chance to check in with my old friends here. I’m out now on the west coast in a location (Monterey, CA) that never gets snow so now I get to live vicariously through you all.

To keep things on topic, one thing I’d lookout for is the front end precipitation rates (now-midnight). Have a feeling those in the WNC mountains will over preform with snow accumulation in the early going for this system, as the frontogenesis on the front end band is probably being a bit underforecasted given the impressive structure seen on radar to come.

For upstate SC, it will depend if the precip rates get high enough to bring the entire 800-sfc column to isothermal. We still have a ways to go for those still in the 40F range, but there is already plenty of mixing for those in the 35-37F range, so once the stronger band moves in, we should see most of the northern upstate (North of I-85) flip over to wet snow before the warm nose comes in.

6

Thanks as always Phil! Not a bad place to be either in Monterey when it's rain and cold everyone will want to be living vicariously through you. 

[PGAWx]

1 minute ago, packfan98 said:

Matches pretty well with the Kuchera map from Pivotal:

I don’t see the Sandhills (6.3) getting more snow than rdu or gso.  

[SnowDawg]

10 minutes ago, insipidlight said:

Hm any reason for this?

Really think they are far too low in the furthest NE county there in GA. Already at 32.4 with snow on the ground that leaves a long burst of heavy snow at the minimum before we have any warm nose concerns. 4 inches seems really low.

[CAD_Wedge_NC]

Just now, PGAWx said:

I don’t see the Sandhills (6.3) getting more snow than rdu or gso.  

That model is only for 18 hours out

[Poimen]

Got an mPing of snow in Clemmons (near Winston). I'm not expecting it, but it would be nice if we could get things started earlier than ~1am here. 

[lilj4425]

5 minutes ago, packfan98 said:

Matches pretty well with the Kuchera map from Pivotal:

Does this factor in sleet and ZR? 12 inches seems awfully high for my area and very unlikely. Gotta be careful with these clown maps as they are usually deceiving. 

[olafminesaw]

1 minute ago, Poimen said:

Got an mPing of snow in Clemmons (near Winston). I'm not expecting it, but it would be nice if we could get things started earlier than ~1am here. 

I saw that too, a tad suspicious. But wouldn't surprise me to get a steady, very light snow starting at around 10 pm. It would be nice to see a dusting before I try to get some sleep.

[donsutherland1]

At 3:30 pm, light snow was falling at Asheville. Light rain was also being reported at Wilmington, NC where 2018's annual precipitation record was extended to 95.96". Meanwhile, heavy rain had moved into Pensacola.

Overall, the major storm that had been the focus of the computer guidance for more than a week is getting underway. Parts of North Carolina and extreme southwestern Virginia will likely pick up a significant early-season snowfall, even when sleet, freezing rain, and even rain are considered.

My final snowfall estimates for select cities are below:

[packfan98]

3 minutes ago, lilj4425 said:

Does this factor in sleet and ZR? 12 inches seems awfully high for my area and very unlikely. Gotta be careful with these clown maps as they are usually deceiving. 

There’s a separate map for freezing rain but not sleet. I would imagine cutting the totals on the map in half would be closer to reality. 

[ajr]

49 minutes ago, burgertime said:

RDU per the Hi-Res NAM would get around a foot of snow before changing over to sleet just based on QPF and p-type maps. 

Where are you seeing that? To me this looks like a rain sounding?

 

[Lookout]

22 minutes ago, broken024 said:

Nam 3k is damn close to all rain for north union...

hmm..not sure why but my last post went missing so here it is again. 

I'll be honest, i'm having issues with the 3km nam. For starters, it's too warm at the surface. Second, i find it next to impossible to believe there won't be more sleet than it shows over northeast ga where it essentially has none. Never mind it is warmer than even the hrrr at the surface. Third, it seems too warm aloft compared to the hrrr. Here is the 12z 3km nam 6 hour 850mb temp vs the 0z analyzed hrrr at 18z...

[GunBlade]

1 minute ago, donsutherland1 said:

At 3:30 pm, light snow was falling at Asheville. Light rain was also being reported at Wilmington, NC where 2018's annual precipitation record was extended to 95.96". Meanwhile, heavy rain had moved into Pensacola.

Overall, the major storm that had been the focus of the computer guidance for more than a week is getting underway. Parts of North Carolina and extreme southwestern Virginia will likely pick up a significant early-season snowfall, even when sleet, freezing rain, and even rain are considered.

My final snowfall estimates for select cities are below:

Outside of Roanoke impressive to see your intitial and final estimates lining up.  Just shows how well in general this has been modeled.  As long as the storm continues as advertised. 

[burgertime]

1 minute ago, ajr said:

Where are you seeing that? To me this looks like a rain sounding?

 

1

Like I said in the post, I was just basing this off of p-type maps and QPF totals between the hours P-type was snow. On those maps RDU gets an inch of QPF while P-type is snow. 

[ajr]

 

[donsutherland1]

3 minutes ago, GunBlade said:

Outside of Roanoke impressive to see your intitial and final estimates lining up.  Just shows how well in general this has been modeled.  As long as the storm continues as advertised. 

The guidance for the most part has been remarkably consistent. I didn’t run numbers for Roanoke earlier, so I don’t know whether much would have changed had I made an estimate for there yesterday.