December 8/9 wave

[RVAman]

2 minutes ago, Cobalt said:

It would be tough to top 8" for Richmond at most. The first issue is that it's not too cold and the ground won't be too cold. That'll shave off at least 1" of snow. Ratios also won't be 10:1 (which is the ratio of snow per inch of liquid). Temps should be 33/34. Since Richmond is an urban area, it should be slightly harder to get accumulating snow. I'd say 5-8" is for sure a possibility, and maybe a bit more if heavier snow bands can cool down surface temps

I don't think it's out of the realm of possibility but living in Richmond my entire life I've grown to get used to things called dry slots that always appear in storms like this. My biggest fear is that this thing actually follows earlier guidance and pushes more South than expected. All in all I do expect to 100% see the first flakes of the season, the biggest question is; will it be a "thing". Everyone in Richmond always hypes up snow, way more than they should. I'm hoping for a lucky 2 inches if this thing plays right. We'll see how fast it moves as well, I've noticed it has slowed down a ton when it comes to leaving the South. 

[yoda]

3 minutes ago, Cobalt said:

How many show 1" or more? 1" for DC is the benchmark for at least a not terrible snowfall

41 of the 51 ensemble members

[RVAman]

While I'm here, does anyone happen to have a satellite image of the Jan 2015 storm that dumped 15 inches in Richmond from the commahead snow? 

[WxUSAF]

18 minutes ago, yoda said:

Could you explain this a little?  Does this mean that there is good dendritic growth?

Yeah, exactly.  MNTransplant posted that skew-t earlier and while it was comfortably below freezing everywhere, the temps aloft didn't look great for dendrite growth.  That GFS profile looks MUCH better.  It's certainly not the best I've ever seen, but we've certainly had far worse. 

[WxUSAF]

15 minutes ago, supernovasky said:

Updated snow map for the area.

 

 

Good luck with that.  

[BTRWx's Thanks Giving]

1 minute ago, WxUSAF said:

Good luck with that.  

I thought you tend to favor the 3km NAM nest?

[RVAman]

Just now, WxWatcher007 said:

He can explain better than I can but yes, that's what I saw with the plot. TT makes it easy by adding the section on the left that has the DGZ. The entire column is saturated. I think generally you want that spot to have 80% or higher RH. You do even better when you have vertical ascent, but I'm not sure how (if at all) you can see that on the plot. Immediately when I saw the sounding I thought it was very nice. 

DT knows his stuff despite his abrasive nature. Not sure about the other guy, but anyone leading by blending in the NAM most for winter storms isn't someone I'd trust. Like many of us up here, we're excited about the potential but if you've lived down there a long time you know bust potential is never zero over until the last snowflake falls (or not).  

DT can definitely be stubborn, he busts quite a bit too in the past year. Yeah, in 2015 no one expected it to snow in Richmond for 48 hours. It stopped for 8 hours and random commahead pounded us.

 

[WxUSAF]

Just now, BTRWx's Thanks Giving said:

I thought you tend to favor the 3km NAM nest?

Me?  No.  I think High Risk has spoken favorably about it for some scenarios.  

I don't think the NAM family does very well at all with winter storms but it sure can be fun to look at.  

[BTRWx's Thanks Giving]

Just now, WxUSAF said:

Me?  No.  I think High Risk has spoken favorably about it for some scenarios.  

I don't think the NAM family does very well at all with winter storms but it sure can be fun to look at.  

Too many red tags for me to keep up. 

[Ger]

Yesterday I felt a comeback gathering like a storm in my bones; I was ridiculed for it. Today, I believe a bigger and better system is developing for Fri-Sat. I won't throw out 3-7" metrowide just yet. But I will 24 hours hence.

[olafminesaw]

3 minutes ago, WxUSAF said:

Me?  No.  I think High Risk has spoken favorably about it for some scenarios.  

I don't think the NAM family does very well at all with winter storms but it sure can be fun to look at.  

I've found it does very well at finding warm layers, and probably CAD events as well. It also is nice to look at when there's banding to see if a changeover could occur.

[WxUSAF]

4 minutes ago, WxWatcher007 said:

For temps we want between -12 and -20 and for RH we want 80% or higher, right? How do you see vertical ascent on a skew-t?

Yeah, more or less.  -10C - - 20C.  The "Omega" plot on the left of that skewT shows vertical motion.  Negative is upward.  

[RVAman]

Just now, WxWatcher007 said:

Yeah. We joke that he likes to hug the Euro. We're all capable of busting..

 

Anyone can bust, absolutely. It's all a bluff until the actual show. Models are keeping precip from RVA until late Saturday, I could see this thing shooting up faster than that into early Friday afternoon. Would it start as rain? Probably. 

[Bob Chill]

6 minutes ago, BTRWx's Thanks Giving said:

I thought you tend to favor the 3km NAM nest?

The 3k nam is fine. Using snowmaps as an expression of reality is the problem. Especially with temps hovering a few degrees above freezing. 

[WxUSAF]

Just now, olafminesaw said:

I've found it does very well at finding warm layers, and probably CAD events as well. It also is nice to look at when there's banding to see if a changeover could occur.

Yeah, it has its useful points.  48hrs out from an event is about the earliest I'd give it any weight, but we are in that window now.  I'd still give it the least weight. 

[birdsofprey02]

12 minutes ago, RVAman said:

DT can definitely be stubborn, he busts quite a bit too in the past year. Yeah, in 2015 no one expected it to snow in Richmond for 48 hours. It stopped for 8 hours and random commahead pounded us.

 

Welcome!  

 

He’s still around here, was chirping a bit during the presidential campaign last year.  His profile says he was signed in last week.

When you see a icon pic of Bill Murray in ghostbusters pop up, that’s him.  

Appreciate fellow lurkers, but one recommendation is to post general comments in the banter thread and keep this thread clean for analysis and reports. 

If this storm does keep ramping up, mods will eventually put this in “storm mode” and moderate messages that lack analysis/forecast.

welcome aboard!

[clskinsfan]

1 hour ago, WxWatcher007 said:

Beat me to it. The trend is our friend right now. Hope we can keep seeing the tick down in surface temps too. 

The GFS would literally be the biggest screw job in my life. Every square inch of VA gets some snow except the 1/4 of Frederick County I live in

[clskinsfan]

Just now, WxWatcher007 said:

If snow gets out there to you it means mby is getting into the heavier stuff. I'm pulling for you. 

If it came true you might have to break out the sickle

[RVAman]

5 minutes ago, birdsofprey02 said:

Welcome!  

 

He’s still around here, was chirping a bit during the presidential campaign last year.  His profile says he was signed in last week.

When you see a icon pic of Bill Murray in ghostbusters pop up, that’s him.  

Appreciate fellow lurkers, but one recommendation is to post general comments in the banter thread and keep this thread clean for analysis and reports. 

If this storm does keep ramping up, mods will eventually put this in “storm mode” and moderate messages that lack analysis/forecast.

welcome aboard!

Gotcha. Well if that's the case, does anyone believe the GFS will push further west, and if so will it bring warm air with it? 

[Bob Chill]

4 minutes ago, clskinsfan said:

The GFS would literally be the biggest screw job in my life. Every square inch of VA gets some snow except the 1/4 of Frederick County I live in

You have 4 model suites to go before declaring that. My guess is the chances of blanking out are pretty slim. The BR doesn't do your area any favors with events like this but once we get a short range trend to push everything NW, it usually keeps going beyond your yard into WV. 

[Cobalt]

2 minutes ago, RVAman said:

Gotcha. Well if that's the case, does anyone believe the GFS will push further west, and if so will it bring warm air with it? 

It surely has potential to, especially if full on phasing occurs. I think whatever the final models show, the actual storm will be slightly easy of, since that's occasionally the case. Not sure if it has to do with dry air, and if so, I'm not sure how dry the air is now. Any push West would bring warm air in, but it would take a large push West for you folks in Richmond to see all rain

[WVclimo]

10 minutes ago, clskinsfan said:

The GFS would literally be the biggest screw job in my life. Every square inch of VA gets some snow except the 1/4 of Frederick County I live in

This one was worse because (1) it was harder for it to miss us (look at how intense the 5H was) and (2) it came at the end of a horrid winter:

http://www.raymondcmartinjr.com/weather/2009/02-Mar-09.html

[Jebman]

NWS just upped Woodbridge VA point and click forecast to categorical levels for snow on Sat.

However, not buying it just yet.

[midatlanticweather]

Just now, Bob Chill said:

You have 4 model suites to go before declaring that. My guess is the chances of blanking out are pretty slim. The BR doesn't do your area any favors with events like this but once we get a short range trend to push everything NW, it usually keeps going beyond your yard into WV. 

Kind of what I was thinking as well. Not that I am shoveling anything significant, but flakes are flying and there is a chance of a sloppy inch or, if lucky, 2, for Eastern Loudoun.  I believe flakes to a coating and car topper - at least a mulch whitener and maybe a few deck photos. I could be happily surprised by more.. and if the system did the head fake today, a total whiff is not out of the question! But I think at least snow showers seems possible now!  If the trending is not done, I will go to sleep happy tonight!

 

[SnowLover22]

18z GEFS really good

[Thanatos_I_Am]

4 minutes ago, Philadelphia Snow said:

18z GEFS really good

How do the individual members look? Good consensus?

[Scraff]

5 minutes ago, Philadelphia Snow said:

18z GEFS really good

Nice!  A broom might not be enough.

[BristowWx]

6 minutes ago, Jebman said:

NWS just upped Woodbridge VA point and click forecast to categorical levels for snow on Sat.

However, not buying it just yet.

Good move Jeb...you’ve been around this egg timer too long...but I will be hitting you up in the obs thread asking you to send the snow my way

[SnowLover22]

How do the individual members look? Good consensus?

I would say so

[Bob Chill]

1 minute ago, midatlanticweather said:

Kind of what I was thinking as well. Not that I am shoveling anything significant, but flakes are flying and there is a chance of a sloppy inch or, if lucky, 2, for Eastern Loudoun.  I believe flakes to a coating and car topper - at least a mulch whitener and maybe a few deck photos. I could be happily surprised by more.. and if the system did the head fake today, a total whiff is not out of the question! But I think at least snow showers seems possible now!  If the trending is not done, I will go to sleep happy tonight!

 

The thing that gives me the most confidence is where in the model runs the nw trend is happening. You can literally start seeing it at hour 6. Lol. Models are catching up to the atmosphere in real time it seems. That's not really that common honeslty. It's one of the reasons the EPS made a very large shift at short range.  That's not common either. 

 

I suppose we can say the ukie saw the potential first but it backed right off at 0z last night so I don't think any model has done well with the evolution of the southern wave. When you see notable shifts in heights at 6-12 hour leads it's pretty clear that this event is unfolding at unusually short leads and models probably aren't done shifting. 

The way it's gone today, I don't think the nw trend is done but big shifts are probably over. The short story of my long post is that your yard will do well enough to be happy. This has always been a SE jackpot setup. Thankfully us folks to the north and west don't have any ptype worries. Everything that falls will be snow. If I lived in southern VA I would be hating the trends though. I know how it feels watching the danger zone approaching and it sucks.