WxMan1

Yes. The 06Z GFS has that more classic Miller A track, which would equate to a more climo snowfall distribution. In other words, MBY here near Rte 50 east of 95 would more likely have some mixing potential than be in the max snow zone this time around.

That's a hint of the Feb 9-11, 1973 storm that brought 23" of snow to Sumter SC. Too bad I was only 2 1/2 and don't remember a thing about it. (My Dad was stationed at Shaw AFB at the time).

That 12Z GFS is straight-up meteorological porn.

Measured 3.75" in Crofton, which along with the 10.25" on Monday 1/3, brings my seasonal total up to an even 14 inches.

What sucks is when you have an operational shift on site.

What a glorious 4-5 day period that was. In West Springfield I had 11.5" on Thursday 1/22/87, then another 11" the day and night of Super Bowl Sunday, 1/25 into the early morning hours of 1/26. Fond memories.

Low was 10.2 here in Crofton. 10-10.5" of snow yesterday, compacted closer to 8" now.

I remember that one. Jan 2-3, 2002. We did very well in south-central VA (I was working at AKQ at the time). That was a clean, all snow event for all of southern VA -- a rarity!

Do you happen to know offhand how the west-NW end did? Short Pump, Glen Allen, Midlo?

The last hurrah. 10.5" in Crofton with clumping flakes now along that last def band. Just an incredible event.

The GFS led the way with this system, let us not forget. I even recall it had *something* at times for Jan 3-4 10-14 days out. In the near term, NAM3 did well, as did the HRRR and RGEM (generally). The sharp deformation and S-N gradient was nailed.

9.5" as of noon here in Crofton, central AA County. 5.5" since 9 am. Just 1/2 inch more please!

Here in Crofton, central AA County... 4" at 9 am... 6.5" at 10 am... 8.0" at 11 am. 4 glorious inches in the past 2 hours. Picking up the pace again. God forbid we go down to *only* 1"/hr! ❄️☃️

Here in Crofton... 4.0" as of 9 am... 6.5" as of 10 am Still pouring snow. ☃️❄️

Absolutely! This is heaven!

4" even on the deck here in Crofton. 32F. Coming down at a good pace.

You're not kidding with the 06Z NAM. We're gonna be right on the edge of that jackpot here in the Crofton-Bowie area.

Steady snow snow in Crofton/central AA County, 32.2F. Pasty 0.5" accumulation.

04Z continues the string of crush jobs across the sub forum from the HRRR. Not concerned about absolute values here with the snow totals (I'd be happy with 75% TBH), but the location (and trends) with the max snow axes. HRRR continues to be not as far south. 04Z HRRR snow thorough 17Z, and still snowing.

It just tells me that it's all about the rates. Convective banding would only add to the disparity of the haves and have nots. You're either getting light snow or mixed precip or ripping fatties, with little in between.

I always thought, when ptype would be an issue, that the 3KM NAM Ferrier SLR would be a good sanity check. Even in this case, when the warm layer is mainly (entirely) surface based instead of aloft. I would look at these totals as the lower percentiles or "expect at least this much". I know this map isn't comforting for most of us, including me with MBY in central AA County. But we are going to need those rippin' rates.

I haven't looked at it yet... But I was just PMd to not look at the 18Z HRRR.

Um...yes please!

I think the cooling due to conduction, i.e. with cold rain at the outset, does a great deal pretty quickly. We often see road surface temps fall into the 30s pretty quickly. But you're absolutely correct -- that first layer would be slush, and overall, the depth of snow on the roads in this setup would be less than that over non-paved surfaces. Would be a mess to drive on. Like you all have said, it's a "rates" storm. We absolutely need that or it's essentially a non-event. Much like November 11th 1987. When it happens, it's a think of beauty. A pasty wet snowfall -- my favorite -- with clumping aggregate flakes. A low probability event to be sure, but we've got the setup going for us, as well as a consensus among most models now within 24 hrs of the event.

The 'warm ground' theory has been debunked numerous times, most notably out west (CO front range, temps in the 70s one day, blizzard the next), but even here in the mid Atlantic as well. Especially along the coast (see Norfolk with the March 1980 snowstorm). Your point about the rates is spot on. Best case scenario I see is we crash to 32 with ripping fat flakes. There is certainly some instability, or very weak stability, to work with within the dendritic growth zone.