MAG5035

That's a classic 18z NAM job if i've ever seen one lol. 10"+ roughly southeast half of PA on the 10:1, and Kuchera coming out to be pretty close to the 10:1 in that stripe. DC and surrounding has 2-4" of sleet.

0z Euro and Euro ensemble check out for Thursday's event. Mostly all snow for everyone in here. Also while I"m at it might as well throw on the 0z WPC guidance blend. That only goes out to 72hr, so probably more snow to be had in the Sus Valley. 0z Euro ensemble 0z WPC guidance (50th percentile snowfall)

Starting to notice the ice on the trees some now. P-type is mainly freezing rain with temp floating 32ish. Do have a fairly stiff SSE breeze now, which may help mix temps up a degree or two (KAOO at 34ºF). The wind probably won't help matters on the ridges though, where the bigger ice accumulations likely will be.

The || GFS does as well. Both are mostly snow with a bit of late mix in the LSV on regular GFS while the Para-GFS never gets mix line above the mason-dixon.

Pretty much all guidance except the NAM (until 0z tonight) have been showing good front snows with varying degrees of mixing later in the event (Euro pretty much an all snow event back in our area). The new 0z NAM now joining the party with the bigger front end thump. So def not a fluke or anything, but a little early to be including accums like that in the grid forecasts considering how rapidly this current one went sideways the last few days.

Might as well put up a pic of the “ice board”. A little over a half inch of ice encased sleet. Ice accrual on trees isn’t too notable yet.

Pinging away here as well. Pretty much all sleet falling moderately.

0z NAM def coming in colder vs 18 and 12z with the mixing portion of the Thursday storm. Very intense front end thump of snow as well.

No sleet at all?

Screaming southerly winds showing on velocity near the 850mb level, >60knots showing up. Basically the reason why this has WAA aloft and associated mixed precip driving further and further north has been so robust. With the lowest 0.5º tilt you can make out the general wind direction near the radar site as well, which is out of the ESE. That easterly component at the surface is going to keep temps from going much of anywhere.

Hopefully we can stay more sleet for a good bit of this event. Looking at the dual pol products on the radar with the higher tilts it looks like the mixing layer is still pretty high up.. roughly about the 4,000ft level (up closer to the 850mb level). So that gives a good bit of time for droplets to refreeze thru the colder 925mb level to the surface.

Ugh. At least on the bright side being caught up in the traffic behind the wreck is always better than being caught in the actual wreck itself.

Looks like a pretty heavy area of precip about ready to get to your neck of the woods within the next 30 min.

On a lighter note, CTP point and click FTW apparently with the 6-12" 48+ hrs out just thru Thursday daytime. Boy if only... lol.

29ºF and moderate mixed precip. Call it maybe a 60/40 sleet to freezing rain blend with a little bit of glazed-in sleet accumulation on untreated stuff already. Tonight's gonna suck.

Yea it's def attainable in the warning area. The main consequences of the models trending NW the last several runs are aloft, with much more robust warming at the 850mb and 925mb level, especially looking at today's runs. Surface CAD is still about the same which will maintain freezing rain, and I know it's above freezing in some spots right now but dew points are mostly in the 20s and this is coming overnight as well. I'm hoping more sleet is able to nose down and knock freezing rain down some here. This is my point and click for tonight, then 12ºF for a low tomorrow night, ugh.

The positives I see for Thursday are a better positioned high pressure to the north and the fact that this is coming pretty quickly on the heels of tonight's system...which about the only thing that's gonna be good for other than ice tonight is finally moving the gradient some as we do have some half decent cold that will come in behind. That aforementioned high actually builds overhead before shifting north of us as this next system approached. So I think we can at least get widespread front end snow if this stronger high holds in. That's part of what sunk us with the current one, which I've mentioned a couple times. Problems I see are that the overall mean trough axis is still going to be similarly positioned to where it is now (a bit too far west for my liking) and that's going to present the opportunity for this to track like the current system, potentially sending the surface low up the west side of the apps to an eventual transfer to the coast. Southern tier is pretty vulnerable to mixing in this setup IMO. Looking at mid-level features, even the Euro is a bit left of my liking with the 850mb low (roughly taking that overhead). The GFS and || GFS had a more focused 850mb low that went west and drew a stronger southerly flow and more mix. The stronger surface high to the north is extremely important for front end snow and maybe getting this low pressure under us, although I"m somewhat pessimistic of that happening without at least some surface low reflection carrying up west of the Apps up to at least the Ohio River. Probably don't want this to slow down at all either. The faster on the heels of the current system, the better chance it has at staying under us.

Can't help but marvel at the craziness of this weather event down in Texas. San Antonio socked in with heavy snow and FOURTEEN DEGREES. Brownsville, TX sitting colder than MDT right now at 32ºF and reporting light snow. The Brownsville NWS was saying in their discussion their ASOS sites aren't even equipped with freezing rain sensors bc well, guess that stuff never happens down there lol.

New 0z HREF showing support for upgrading that swath of watches to what would likely be an ice storm warning. This is the accrual algorithm. 24 hr snowfall:

Yea it's not going to get that far over, it's too cold there lol. However, pretty much all guidance has moved to running this surface low up the west side of the Apps basically up to SW PA before it shows any signs of jumping to the coast. That's not going to cut it, we need this to stay under PA. Really the only difference this makes for central PA is it just makes thing's icier (more freezing rain) since there is enough of a CAD setup to hang in surface temps near or below freezing over all the area for a good portion of the event before maybe spiking above freezing into the LSV below the turnpike right at the end. This is going to affect the northern tier's snow accumulation's some as the mixing is likely going to drive pretty far into northern PA now with a track like that. Still should be a half decent snowfall up there though. A stripe somewhere in the central counties is probably going to see a decent sleet accumulation (1-2") where somewhat deeper cold likes to stay anchored. The silver lining? The majority of the main wave of precip associated with the surface low Monday night is out of the area in about 10hrs or so. Then we can focus in on the next incoming mess Thursday.

Speaking of AFD updates haha.

Yup lol just saw. It does make sense since there's still time to review more guidance tonight ahead of this. Saw Mount Holly go right to warnings for half their CWA and figured CTP was about to do the same. So watches on a swath of south-central PA for the heightened ice concern (possible areas of .25"+). Some of the central/north central watch counties plus the non watch counties to advisory for more mixing eating into snow totals and likely more of a sleet event over ZR for the mix type. Also, I understand the LSV folks kind of tuning this out for the Thursday one but this next one starting well, tomorrow is still going to get everyone in here with at least a fairly high impact advisory level winter storm.

Ice storm warnings up for bordering counties over in Mount Holly CWA all the way down to Lancaster. This going to be another event CTP goes straight to warnings for a bunch of counties?

Probably never. That is a gigantic expanse of the southern US under winter storm warnings. And those wind chill warnings that cover pretty much the entire north central US also are including a large portion of those winter storm warned counties. Def a historic and wide reaching arctic air outbreak.

Only real big difference is the more robust high pressure progged to our north and NE for Thursday (and overall in the rest of the CONUS. That was the kind of high pressure models had north of us for Mon/Tues a few days ago whenever it was looking mostly snowy in PA. Helps deflect the surface low to the coast in time and at worst anchors a CAD wedge if the low tries to work up the other side of the Apps. Going to be extremely important to maintain that, because Thursday's storm could easily do the same thing the next one up seems destined to do, especially in the LSV. Mon/Tues storm arrival: Thursday storm arrival: