Terpeast

Low end map from LWX

Fwiw 3k has the sleet line a tick south at hr 34.

I usually don’t report sleet on top of snow. This time I will, but I’ll take separate measurements to get the snow accum right when it flips, and then get the sleet accum just to differentiate the two when reporting the total. Also given that sleet is counted, the bullish nws forecasts make a little more sense.

RGEM mixes us at the same time/hour as the Euro does. Gives us 10" areawide before mixing. I'll take it!

Here's my first call on what I think is going to happen in our forum. More confidence in a 30 mile corridor along DC/Balt and NW. Less confidence in the SW quadrant of this map (so please don't hammer me if you live somewhere like Roanoke or Cville.

Busy times ahead!

Yep. This is the kind of storm I've often seen when I was a kid. PA gets the most snow while we mix. I was jealous of State College then. But they've had a terrible, terrible run at snowfall in recent years. Like, worse than us.

Sorry, meant 25%. iow, use 75% of gfs values

Just catching up. So the gfs didn’t fully cave, but pretty much all guidance met in the middle. I’d cut gfs accums by 75% though to account for ip/zr. That gets us to 6-10 for dc/balt metros, with a foot being in play for NW suburbs (1-2 counties off from I-95 and north of 50)

Thanks for pointing that out. The 12k and 3k might as well be two different models. May sound like a weenie, but I’d lean more on the 3k within 48 hours of onset.

From the POV of NWS, their mission is to protect life and property. Given a difficult call between forecasting a few inches of plowable snow/sleet and a devastating ice storm, where it could really go either way or have both in the same region, I think they would rather warn people of the worst case scenario. Because if they don’t, and the ice storm happened, that would be a mission failure on their part, and it may cost people lives and property. Yes, there is also risk of a busted ice storm forecast in the eyes of the public, but that would be preferable over the former scenario.

So that’s 4z-12z or 8 hours of snowfall before the flip.

When JB posted that, he just guaranteed the bullish gfs scenario isn’t gonna happen. Thanks a lot JB!

That would be welcome news for S VA if its mostly sleet instead of zr.

Looks realistic tbh, can’t say I have anything to pick at against

Minimum 12 hours of snow for DCA before flip, with progressively increasing intensity.

I was hoping to see some more consensus with either gfs caving to other guidance, or both sides meeting in the middle. But they could not be further apart. We may have to wait until 0z tonight to see where this is heading.

They may be going with a blend of the Euro and GFS. Which isn't entirely unreasonable, just not something we would run with ourselves.

I’m right on the navy blue line just NW of IAD, and 7-12” is consistent with what I was thinking.

10” would be fantastic!

Also think of it this way… we’re finally getting a classic N&W storm

If I can beat my 7.6” in last year’s storm, I’m good.

I think a blend gets us to 6-10" DC metro, 8-12" NW, 12"+ out up in WV panhandle through PA SE of DC 4-8" with lots of sleet, and south of EZF start to see icing (subject to change ofc)

It was awesome. Started out raining briefly, then flipped hard and the rates - oh man. I stayed up the whole night. Worth the sleep sacrifice.

We've got another busy week coming up on the heels of this upcoming winter storm!