MAG5035

Had another 0.3” from a squall when I was out cleaning up earlier, so bump the total up to 5.5”. Gauge is melting down now so I’ll see if I can get a ratio. Winds are kicking up.

It’s possible, that area would’ve been right in line with the bigger totals further east. There were also 10+ totals reported all the way back in eastern Ohio with a stripe of warning totals just below the Pittsburgh metro.

Last event was my worst, or at least certainly the worst I’ve had anytime recently the way one that busted in the true central and north central. I got close to technically verifying a warning but was within the forecast range of 4-7”. Even up here roads took awhile to get snow covered and they never were super terrible at any point. Road crews were also really on this event as well.

5.2” is the final total here. Temp has fallen back to 23.5ºF My snow forecast looked like it did okay mostly. Obviously that impressive FGEN band really overachieved in a narrow stripe that carried all the way to the east and to the south in the LSV below Harrisburg it underachieved. I basically expected a general 3-5” and highlighted that dashed area to cover the expected area that narrow band was going to set up somewhere within, so I caught some of it and was a bit south overall and didn’t stretch it enough. And then came up short in a corridor just below the band in the southern tier. Dynamics and temps aloft were as advertised as evidenced by the fluff bomb that ensued within the band but didn’t expect surface temps to be the issue that they ended up being. Also didn’t realize that LWX had upped their totals to 5-8” in a large swath of their northern CWA yesterday prior to the event starting. That’s a brutal bust for them down there.

There’s been some half decent back building on PBZ radar. Starting to have a more NW-SE component to its movement. Have to see how well that translates over the mountains to the Sus Valley.

At about 4.5” here, with light to moderate rate. Temp down to 28ºF

Wow, it was about 2 hrs ago or so you posted that you were working on your first inch.

The 511 cams on US 322/22 on both sides of the Duncannon bridge look like they’re getting pounded too, as well as the rest of that stretch down to I-81.

Well I dunno where exactly in Harrisburg everyone there lives but it seems like it’s snowing everywhere in/around town there now looking at 511 cams. The 700mb FGEN band is setup overhead as well. This should pile up pretty fast.

Steadier stuff should be working into York/Lancaster here pretty directly by the looks of LWX radar.

Just got home here, was out for the evening. Nice event ongoing with 3.5” down and a nice moderately heavy rate currently. 29/28ºF

3:40 after nooners. 37º/16ºF light wind and cirrus overcast. Max wind gust of 38mph occurred around 4:30 this morning.

My bad haha I didn’t realize they divided up the warnings up that much.

Here’s some of the western part of that, CTP went warnings all southern tier and bumped up the advisories in the next tier to warnings. Western southern tier (Bedord/Fulton/Franklin) is 5-7 and Laurels is 6-8.

Looks pretty reasonable. I wonder why his northern fringe goes to infinity at the PA/NY border.

This is the kind of event our area overachieves on if the good precip and forcing are north enough.

Haha I didn’t know everyone was putting their snow maps out while I was working on my post. The snow map game is strong in here today.

My map for this. Tried to make a compromise in blends but perhaps on the bolder side. I anticipate CTP needing another tier or so of advisories in the central and upping at least the western half of the watches to warnings. 3-5” amounts should be common in the main swath. Big question is in or near the area I hashed. I was going to get cute and try to highlight two distinct areas but I’d probably need a bigger map. Any rate I feel the hashed area has the best chance to see an embedded swath of 5-6”+ and/or local totals of 6+. Best 700mb forcing is in there coupled with 700mb temps in the low minus teens. The fluff bomb potential is high with that. The southern Laurels will have that plus the benefit of some extra upslope forcing and colder surface temps.. hence the distinct 5-8” I anticipate there. The other snowfall max is probably somewhere in the northern Mid-Atl (northern VA/northern MD, where better 850mb forcing will be. That won’t yield the bigger ratios like the 700mb dynamics that should be residing in southern PA.

Yea that is true, and they honestly looked really good by the end of Sunday when things shifted south a bit. They upgraded high confidence counties to warnings and kept the watches that reached into the Sus Valley. The big shift south Monday at <24hrs til go time really sent the forecast sideways. Then they never downgraded the warning they had for here last event either when it was abundantly clear AOO-UNV wasn’t getting 6+. Even JB said just prior to the event they needed to get rid of the warnings for the State College area haha. They just turned it into a 2-4” winter storm warning, which I’ve never seen before. Then of course the high confidence counties above I-80 that were originally warned didn’t even see any snow in the end. What happened with the Tuesday event was brutal, and I don’t know if there was much to be done with that kind of a shift in guidance. I don’t expect anything drastic to happen with this system. Precip shield should have much less of a northern gradient than Tuesday and big thing for our area is determining how much of southern PA to put in advisories IMO. Wagons north seems to be the theme of happy hour so far (need the Euro yet).

To be fair, LWX’s watch statement is for most likely outcome of 2-4” with isolated 6” amounts in heavier bands. That’s a bit of a stretch for a region that needs widespread 5” or more to verify a warning, technically. Both ends of the spectrum between CTP and LWX haha.

Certainly there’s support for the southern Laurel’s to have one. You’d think a coordination with LWX/PBZ having watches in Garrett/Western Alleghany in western MD (LWX) and Eastern Preston in WV (PBZ) would possibly warrant a watch up into Somerset. Those high elevations are probably going to be low-mid 20s during the height of the event. Temps aloft are supportive of a higher ratio event and couple that with some upsloping and I believe some of those short range models are onto something having 6”+ up in those areas. I dunno about watches east of that yet. Like I said a bit ago, probably don’t need to rush the advisories. I’d wait to see 0z and then go from there. I’m surprised there hasn’t been a mention in the HWO about any accumulating snow or prospects of it at all, though. I dunno, I doubt it but maybe getting burned on models bailing south 100 miles in the 24 hr lead up to Tuesday mornings event made for some cold feet.

Weird take, the only thing that represents what CTP is talking about in their AFD was the 12z GFS op. Everything else supports advisories in at least the first tier or two of counties in southern PA currently. No need to jump the gun issuing them just yet but I’m not sure what guidance they’re basing the current take on. Also weird, the snow here has transitioned to graupel

Snowing here now.

Got dark in a hurry down here. Waiting for the precip to reach the ground. At 39 with a 26ºF dewpoint so probably can manage some flakes out of this.

You’ve done it now, I’m using math haha. Trying to see how Pivotal calculates it’s Kuchera vs WB. So, basically it applies an equation that uses the max temp in the lowest 500mb. In this instance the warmest temp is the surface temp.. which according to the NAM holds at 31ºF for the event. Applying that equation using the surface temp (31ºF = 272.594K) yields a 9.13 to 1 ratio via Kuchera. Right around its output and also <10:1. WeatherBell’s output is greater than 10:1 so something different is being calculated, whether they don’t use temps right at the surface or maybe they’re applying the bottom equation for all temps, which technically would be wrong. To simplify, the bottom equation is used for the max temp being less than or equal to -2ºC. Plugging that same temp for MDT (about -0.5ºC) into would give about a 10.5 to 1 ratio. Interesting, maybe the codes cracked on that. That would definitely make a difference in map output with marginal temps.