Heisy

12z Ukie gives us breathing room as it focuses WAA thump south. Fine by me at this range

There's also a shot at less than 10:1 too especially near the city at times if we see sneaky warm layers. 

That was a nice shift on the ukie, starting to have some convergence in guidance here. The morning thump should be fun as hell. 

11 minutes ago, Moderately Unstable said:

It is an in house model. It's WSI's (the weather channel's parents') internal convection allowing high resolution model. They're also, fun fact, the one's developing deep thunder (aka graf)--which once operational will use a 15km grid, BUT, will have a 1 way 3 km upscaling in the conus--which they are suggesting will let them do away with convective parameterization (so that they can actually model individual thunderstorm cells). One way because those 3km cells won't then feed back out to the larger domain.  Basically the small cells get initialized by the boundary conditions of the larger domain (15km), then, operate independently. Now, if they're successful--this would be fantastic for mesoscale forecasting because it could (theoretically) enable one to almost predict in advance which cells would have sustained rotation with high accuracy and locational precision (SPC and NSSL toolsets allow for meso tracking already but it's more of a general "idea" than precise here at this time type of data...even though the output simulated radar sorta acts as though that isn't the case). But color me skeptical. They're working with IBM on this--I believe with a machine learning type of approach...in any case from what I've seen of the large domain GRAF so far, looks promising. Neither is available to the public (frankly it isn't even available to everyone in the private sector), and they're EXTREMELY protective of access to it, which is why I don't post the maps here. You can get in some actual trouble doing that. Like any model, it's guidance. But for whatever reason, it really is "worth" WSI's protectiveness...it's good. I've used it to chase individual thunderstorms before by using it to time out to a half hour interval where a particular cell would be and where. For mesoscale enhanced setups like this one, it tends to do a good job. 

 

WRT the || Euro, keeping up to speed on the rapid-fire-changes of the operational and ensemble guidance while checking model verification and current obs, and doing my day job...haven't had time to look at that today haha. Link?

 

Thanks for the info!

 WRT parallel euro, Someone linked it in the mid Atlantic forum earlier today, it had weatherbell graphics but I couldn’t locate it on the site... anyway...

Any idea why the Para GFS, 00z Ukie, and some others have a “snow hole” over Philly? Is it because we miss out on the waa fronto thump and the coastal snows just NW? Maybe the h7 low tracking too far inland? 

1 hour ago, hazwoper said:

0Z NAM clown map paints 12+ Of frozen for SEPA.

Discuss

This storm should (crossing fingers) have a really fun 3-6 hours on the front end. 

10 minutes ago, Moderately Unstable said:

I love a good finale, don't you? 00z RPM keeps the trend of the 18z and 21z runs....corridor mostly snow, gives 12-16 widespread totals. Places like BAL & IAD are modeled at between 20-24" (outside of our domain but notable). Gotta keep watching this though. There's a sweet spot here for the track of the sfc and 850 low centers. The models have hit that place now. My internal sense here is, the whole 12+" thing...we've been down this road many times. Models a couple days out provide clown like totals. I think we're reaching consensus now that impacts are going to be enough here--in the form of snow--to most likely at some point down the road req a WSW for the corridor and areas NW. Exactly what the totals are...probably too soon to say, but I sure do love the 00z runs coming in now. If I were a TV met this is when I'd start talking more substantively about the "potential". 

Is RPM an in house model? Is it available to public? Also what is the deal with the new parallel euro? It was a pretty big hit earlier today.

Winter ain’t dead yet with this look. Lala land but we take that cold air transport setup

54 minutes ago, Thinksnow18 said:

Lightweight stuff for sure. I thought I wasn’t going to see 2”+ snow rates again this year but tonight might bring that again!

I couldn’t make the trip in time so you guys will certainly jackpot. Radar looks good enjoy fellas! 

For the city it is going to come down to where that initial fronto banding sets up. This storm won’t be able to give us snow from the coastal since the upper levels are t great. Think of PD2 where that initial fronto crushed DC and that area. I’d rather be north right now of where GFS has it so no complaints yet. That is a way we could get “screwed” though where initial waa banding is south thru Md line. Then mid levels toast for the coastal part. Places to the NW of city may be able to hold Onto snow longer from The coastal. It’s why you see the snow hole over us on the 18z para gfs

@Ji pretty wild DCs biggest snow of the year might come from a storm which was originally pegged to be practically a cutter in the medium-long range by the GFS. You almost never see those types of storms trend this way lol. This winter is goofy

I love your guys location for this one. With the exit side of thr trough trending more progressive the initial fronto aimed right at you. Should make for a fun morning. Usually big wide open gulf events like this you’d expect NAM to be N. It should cave soon 

14 hours ago, snowwors2 said:

 

Too much volatility...

Another wait and see (but much waffling in between)!

Last night on 11pm NBC10, Steve Sasna said we had caught a break for Monday Tuesday because the models had warmed...NOW look where we are less than 24 hours later (and it may/will change again by tomorrow evening)!

This widespread deep snowpack has A LOT of staying power that no models will forecast accurately...Seen it many times over many years!!

Are you mixing up the events? Tonight is a no go. This event is Thursday that has the chance for legit snowfall. 
 

Was thinking about starting my first thread for the event since were under 4 days, but idk haha

3 minutes ago, psuhoffman said:

It’s early but I can already tell the NAM is going to be way NW of all the globals. Way more amped up and it’s directing the lead wave of energy to our NW 

3km is a good shift SE of 12km With heights so that’s a positive

Edit: well maybe slightly better. Gonna need a lot more though. 

Just now, psuhoffman said:

You all can pretend it doesn’t matter but it Sure would be nice to get the NAM on board here soon!

It’s been really good hinting at progression this winter. I agree. Probably because I’m a paranoid baby though. 

Better map

Snow comes in like a wall. Good stuff

kuchera for comp.

10:1, kuchera is less I guess because of temps? 

12 minutes ago, LP08 said:

I suppose the one thing that's consistent so far on guidance is the surface is frigid.  Don't need rates to overcome 33-35 at the surface.  I would take a 6hr dynamic system of all types of precip at 28-30 degrees.  1-5" of snow/sleet would be fun.

Yep, comes in at a good time too. Early morning. Wake up drink some coffee and watch the radar light up with some fronto banding. Nothing better. Let’s gooo

1 minute ago, psuhoffman said:

Cmc has some very heavy banding aimed right at DC then too. It’s very questionable if it’s snow/sleet. Flips back and forth for a few hours in the precip type plots.  Nothing else updated yet. 

Yea on stormvista plots I have no clue what ptype either. 

1 minute ago, TugHillMatt said:

Far, far, faaaaaaar away from me.

That's my best advice.

Haha, so you know the tale of the Heisy curse. I kind of broke it though on my recent chase to Dover NJ, finally didn’t get screwed

Hey fellas if I decide to come chase where do you think I set up shop? Roc? 

3 minutes ago, caviman2201 said:

Doesn't it tend to run warm too?

We have a met on Philly forum that has done some stat verifications on it. It runs too cold. Overall it’s done a decent job this winter imo. Bottom line is you want it to be showing snow if there’s a chance. Just another piece of guidance though. 

4 minutes ago, SnowenOutThere said:

Does the 18z Euro look better, the same or worse than the 12z

I’d say both heh. Heavier precip on lead edge. Stronger HP but Thicknesses a touch N since main wave is slightly stronger.Here was 1hr snow on last period. This was some heavy stuff 

This looks like one of those 6 hour thumps. So it’s how much snow you can squeeze in that time period. You’re usually looking at 6-7” tops. Hopefully we can pull off a 3-6

1 minute ago, stormtracker said:

4".  I'll take it.

Maybe I should re-word that

Best part is it comes in hot and heavy

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