DDweatherman

I can see the isobars still looking favorable for us, NE winds and flow at 850 isn’t off the ocean just yet.

Embiggening is a new one. Visibility creeping down here off 140 in Westminster. 26.6 degrees, little over 1/2”

<1/4mi lol

I should also note winds still out of the NNE/NE at the moment. You can even tell with the slightest bit of subsidence as the good returns move over us with them taking their time.

I think we can really pile it up the next 5-6 hours and I’m willing to bet our column holds. There’s going to be 1-2” an hour rates with some places even besting that through 6PM.

I’m thinking somewhere in between. The heavy rates are overcoming the warm nose at the moment all the way into ROA. Mesoanalysis running right on tap it not a bit colder than predicted at the mid levels, with surface temps running a degree or two below.

Starting to stack up outside Westminster. Like Joe said, pay attention to the 700-850mb fronto page on SPC meso. If that verifies some of the maps Millville was talking about, it’ll be an electrifying afternoon for rates in a lot of spots.

Lots of folks gotta love the HRRR for this afternoon. Basically 1-2” an hour rates north of the beltway into C MD and NW. fronto is increasing in the area and the low is starting to deepen off the NC/SC coast.

I like where you are, especially with current trends on the nowcast/meso side. Primed for 10-15” there

Snowing pretty good in Westminster, most things covered. 140 wasn’t too bad moments ago, side roads mainly covered already so could be a little slick. 27 degrees

Here you go, correlation coefficient.

I mean no denying the short term trends. That RGEM depiction is markedly different than even 6z

That’s money Jay.

I actually like the meso obs from SPC right now. Checking the various levels of temps and coupling that with obs in forum make me believe the HRRR won’t be completely out to lunch. The NAM, on the other hand, looks like it was off by quite a bit.

Where’s @MillvilleWx, I’ll repost what he said overnight for us folks in the northern counties: “I'm gonna say it now. Someone north of I-70 between 20-00z is gonna see some absolutely insane snowfall. The 85H frontogen is beyond incredible for that area during that timeframe. This reminds me of some of the surprise overperformers in recent past with front end thumps.”

And max-ing out the DGZ. Might even be at 12:1+ in that band with no defined warm nose.

Light snow in Westminster has begun. 28 degrees

I like where the high is located (1038) just N of NY. It’s hanging in there pretty tough and has been running a few mb stronger than progged. You can see with the bending of the isobars it’s still leaking the cold air to our north into the area on some NNE/NE winds at the moment.

Final Forecast for Posterity (Most likely in parentheses) BWI: 2-4” (3”) DC: 2-3” (2”) IAD up to leesburg 4-6” (leaning 4“) FDK: 6-10” (8”) Westminster: 5-8 (6”) HGR as well as OKV (Winchester): 10-15, closer to 10 at HGR, closer to 12 near Winchester Thinking a decent WAA slug and do like the short term trends on early arrivals on mesos. Our dews/obs as well as the current 850 scheme look respectable. Overall, I’m not bullish on backside love, but it’s gotten a lot more respect and the 0z GFS brings it very close to the M/D folk. There could be serious sleet with some actual accums thanks to the warm layer at the 750-800mb level N/W of 695 out on the 70 corridor (namely Hunt Valley to Eldersburg to Westminster to Frederick). These folks are going to stay below 32 (likely sub 30) most of the storm and the warm nose is elevated enough the low level cold will make Sleet much more a threat than any possible ZR. These are also the places most likely to get 1-2” on the backside with the potential for more if the chips fall correctly. Mix lane stops just shy of Winchester and HGR.

24.8/18 out here by McDaniel in Westminster.

HRRR looks solid at 0z for a lot of folks in the CMD/DC metro to get thumped at least with some snow initially. 6-8” across the folks north of 70 East to 83 in the “Hereford zone”.

Well PSU, we're down to the HRRR then huh?

Well from a high level it scoots out east from our latitude. You've seen on some models it crashes the column even for us, along with the mid-levels closing off. If the low trekked up over NYC, you wouldn't see the same results there.

Which is bogus of course. But that also leaves the door open...one of the models has to be wrong with where they are putting the low, and there is signficiant discrepancy amongst Op's at the moment and even their ensembles. If the track of the GFS or even the NAM at 18z are correct but the euro has the thermal scheme correct, a lot of folks would be surprised at the outcome. The airmass is a lot more formidable than some have given it credit to this pt.

To be honest, there has to come a time where you take a look at the consensus track for the LP center and the h5, steering, and the flow in a nowcast. That coupled together still makes it really hard to expect a low to go over Baltimore. Models seem to be struggling with the double barrel look and where the true MSLP is going to end up. As Wwxluvr said, this is a really sensitive set up, and I think that is reflected with regards to low positoning more than anything. The euro is showing some of the biggest "snow maps," but has the low the furthest west. That's after the NAM & GFS moved it SE @ 18z. I'm more focused on some of the short term indicators/mesoanalysis to see where our low pops and how the ML's react in response to that positioning.