SnowGoose69

Given this is pretty weak if it did produce decent QPF there would likely be an extended period of snow. No question you'd have to watch the mid levels but this is not an event where you'd torch the mid levels after only a 1-2-3 hour period of snow

The question is if the overrunning aspect can produce when it bumps into the high. You can see on most guidance and ensembles there is a period where the disturbance produces less QPF over OH/PA then invigorates again. That is somewhat suspect unless we see that invigoration as a result of overrunning because the disturbance itself is not much to love. One thing to like is the Euro likes this system and has been running hot lately.

The Euro seems to love it and its been on fire so far this season so that is somewhat comforting for now but timing when these things pulse is nearly impossible. One of the CIPS analogs was 1/6/89 which had some similarities to this. It blew the doors off over the Midwest then sheared out and weakened over the OH Valley but when it slammed into the high that was over the west Atlantic and SE Canada the overrunning produced "big" snows across NE and down into NYC.

Not in this case. This thing is strung out and weak. I'm more concerned with QPF amounts than I am mid level WAA. This is one that if we had a stronger disturbance could have dropped solid snow amounts. But I am skeptical at the moment this may trend drier and drier.

This thing is too sheared. It does seem as if it goes into a period Sun night/early AM where it dampens somewhat then without much reinvigorating of the disturbance it spits out bigger QPf amounts again. Maybe a product of overrunning but I could see this thing just going to chit as we progress.

I think someone sees a nice period of snow with this because the initial surge is coming from a pretty strung out disturbance. I would be more worried at this point that we see QPF drop off then a warming trend because some of the guidance really shows this as a sheared mess.

All it really can do is prevent a massive SER from developing so you probably won’t see a 570dm ridge with a high of 75 as you might see if the AO and NAO were strongly positive

This is one of those events that ends up pissing people off have better snow climo and see someone south of them get pounded wherever that WAA axis sets up. You can see right now someone will get slammed by a fronto band somewhere in southern PA or central NJ while NYC up to BOS gets 1 inch

It’s not a La Niña so I don’t know why so many forecasts had a doom and gloom winter from NYC-DCA. Considering December was supposed to be the worst month and NYC could still get out of it with above normal snowfall (I think they only need 3 more inches to do that). I think many of the forecasts at least for them might bust. PHL/DCA remains to be seen

The Pac has to be extraordinarily bad for a -NAO/AO combo to not at least give you some chances. Generally as long as there isn’t a death vortex in the GOA a bad Pac can be cancelled out enough by the Atlantic. The Pac basically sucked in 10-11 even in December and January but it didn’t matter with the -NAO. We still did well. I should add also the Pac influence becomes less and less against an NAO/AO the later you get. We saw this in December 96 and I believe December 2012. Bad Pac was able to beat out the good AO, NAO or both but if you have the same thing going on in later January the Pac will lose more frequently

It’ll be a solid event if the system is weak and not too amped. Could see a 3-6 inch event before the turnover in that case

This one has to be weak because the high positioning and area which the storm approaches from aren’t ideal for a significant from end snow here outside of NW areas

The GFS is horrendous with SWFEs beyond 84-90. It sometimes might have the general track idea right but it usually has everyone south of BDL raining for the entire storm or snow for 1 hour. Once inside that range it’ll usually start showing the front end snows

Most of these events involve either a massive wave of low pressure riding up behind the front or they occur a day or two after the front clears like the 98 event or the 2/2/96 storm. The only case I can think of that didn’t involve a strong wave and the snow came right behind the front was December 1993 and that was about a 40 mile wide area of snow

12/24/98 is now the top analog for this event. I think someone mentioned it a couple of days ago here

It’s been ticking SE but it’s now in its range and it’s NW of the Euro and NAM. The RGEM runs sort of like an MLB team’s bullpen. It’s either hot or cold winter by winter and it takes you 2-3 storms to see its tendency. It has performed well so far IMO going back to mid November though it had a few localized busts on the storm last week. It was 100% useless last winter

I’m not sure if that LE was correct though. It is pretty darn accurate today at Central Park but I don’t believe there was an ASOS there yet then they were using some sort of old school home weather system for readings from October 1993 til July 1996 when I think the ASOS was put in so very possible that reading was erroneous

12KM NAM through 15 hours has like triple the QPF across PA and down into MD//WV from prior runs. We will see how that translates over next 12-18 hours

The only question I have is if the whole thing ticks NW. Regardless I think there will be isolated 5-6 inch amounts with this though the majority will only see 1-2 and there will be a screw zone, possibly in between 2 areas that do better

Back after that Euro upgrade in 2014 or so this was an auto shift 50 miles west. It was terrible the first 2 years or so off that upgrade being too dry and flat with anything that wasn’t a heavily amped system but after the latest update it seems to be about as good as it has ever been. I haven’t even been seeing it’s 90-120 overamped tendency the last 6-8 months.

These things always end up west the last few years because of the tendency of any degree of ridging in the western Atlantic to be stronger than modeled, even at 24 hours you usually are good for a tick west

The RGEM was way too far west at 12Z and it tends to have an amped bias beyond 30-36 so I expected a tick SE over the course of the next few runs

You have to be wary here with their technically being a “WAR” right now. Anytime the last couple of years we have a system or boundary that we have concern could push too far off to the east that ridging is stronger than expected and we get a further west or more juiced system

There was some pretty nasty dry slotting from about NYC to Nassau for a time. Quite a few places there saw only 16-22 inches or so. I want to say BDR only reported 17-18. We’ve definitely had some oddball measurements over the years at the airports and NYC. That Newark measurement on 2/11/94 I think most agree was wrong. NYC’s measurement on 1/22/87 I had an NWS Met tell me 18-20 years ago they KNOW was wrong. Recently we obviously have some real awful ones but even before 2000 we saw occasional sloppy reporting

I’m not a big Bastardi “agreeer” but he’s probably right in this case. The Euro in events like this will tend to be too flat or dry. I’m definitely thinking more NAM/RGem is more likely. The NAM May have sucked at 12Z in regards to QPF but that was probably a blip as it still looked okay otherwise