The Iceman

I'm hugging the NAM idgaf

Euro is better than 00z, at least most of the area sees some snowflakes. Just need a 50 mile jog north and most of us would have a solid advisory event, it's doable right?

Yep writing was on the wall last week, but it was far enough out in guidance time that it could have reversed... not the case unfortunately as all guidance now progresses the MJO through 4-6 and by the time we get to 7, winter is over and there will be no cold air left to recover. I'm going to actually LOL though if we get a great coastal track in this time period that is all rain because the cold air has left the continent. Kind of like what the GFS shows long range.. Just one final shot in the nuts as Winter 21-22 progresses into spring. This winter definitely could have been worse down our way though. Not too many 2nd year mod-strong nina's even have 1 warning level event so we at least lucked out there unlike further N. And the SNJ/DE folks actually had a good winter snow wise when they are usually on the short end of things typically. Hope you are right wrt it being a Modoki Nino next year. I'll take active SS with seasonable cold and take our chances. Seems like we are well overdue for a winter of sustained Atlantic blocking as well and not just a couple weeks followed by endless +AO/+NAO.

12z ICON is a 15-18 hour storm, snows all day on Sunday into sunday night, haven't seen the snow total maps but it's got to be 6-10" from upper bucks/montco S and E. Only problem is that it's the ICON showing this...blind squirrel has got to find a nut once in awhile right??

At the very least, I think most of the forum will see a period of light snow this weekend even if it likely won't amount to much or anything. Enjoy it, because it very well could be the last snow we see until next winter. GEFS and CFS weeklies are ugly with a strong PV until around mid march. By mid march, you really need a potent system and a lot of luck to produce a decent snowstorm.

What's crazy is that it honestly looked closer to the CMC than GFS through 84 or so imo but the northern vort pushes the SS out to sea instead of phasing it. Just a real delicate set up. Nightmare to forecast. I wouldn't be confident on any solution until we are 48 hours in or we see some kind of consensus between the globals. I mean really, every single global model has a different solution. Yes some are the same outcome wise, but how the storm develops is different on all 5 globals. With so many vorts zooming around with no blocking, I just don't see the models having a good grasp on this storm until we get much closer. I think because of the lack of blocking and lack of spacing, a sheared out E solution is favored at this time though but as the CMC and even GFS has shown at 12z, small changes at H5 are going to have a big effect on the final outcome. We could certainly still get lucky. Seasonal trend definitely favors a Euro/UKMET like solution though at this time.

Spread-shot so far at 12z that really shows how delicate this threat is. The UKMET is well east, CMC is an inland runner, GFS kind of splits the goalposts with a lean east. Pretty big spread on the ensembles still... We are no closer to getting clarity on this event than we were 12 hours ago. I think the CMC solution is the most unlikely though and would be shocked if things went down like that... it also moved like 200-300 miles northwest in one cycle. UKMET gave most of us 8-10" at 00z then this run has us only getting in on the northern vort 1-2" and being well offshore. GFS is the only kind of model with any sense of consistency so far but even that has been bouncing around 50-100 miles each way the last 3 runs. Hopefully the Euro brings a little bit of clarity. If it sticks with the 12z UKMET like solution, I have to think the eastern solutions would be favored at this time. But still lots of room for things to change as subtle changes at H5 are having big implications due to the spacing and timing of the vorts.

12z GFS is a bit more progressive with the SS wave and as a result it's a bit further east with the coastal. SNJ wins again However, still far from a finished product here. Such a delicate set up, I expect we see pretty decent shifts in all directions these next 24-36 hours. I would be happy with 3.5" though, can't say the Lehigh Valley folks would be happy though lol

12z NWS blend of models is more bullish than it was at 6z or 00z on snowfall totals.

doesn't look too far off to me at hour 90, some slight timing differences and as you said less vort interaction but nothing jumps out as massively different. With how fast the flow is right now, I doubt either model has a great read on this event yet. Next 24 hours are going to be crucial as by then all pieces should be well sampled. Euro GFS

last night's UK is also on team GFS/ICON Still so much time left though and I'm not confident until we see multiple runs of the same thing but it was good that 06z GFS improved upon 00z.

I'm not giving up on Sun night/Monday yet. ICON is a shitty model yes, but it shows how we can potentially win with this system. You look at 500 MB and the globals are all over the place with timing of both the NS and SS energy. This could be one that sneaks up inside 4 days as data is better sampled. Need that NS system to dig more like the ICON and the CMC to an extent. And need the SS to not hang back like the ICON. It's a fragile set up as Ralph would say because there is no blocking but there is still room for a snowy outcome. At the very least, may be able to score 1-2" on the N stream energy alone.

This vs This Will determine our fate late month. Neither is particularly a classic look but we could still score something with the GEFS due to the cold air lurking nearby. If that gets dumped into the west like the other ensembles it's a shut the blinds look until March.

There's really 2 camps for where that cold air wants to be dumped on the ensembles. The GEFS keeps the pac ridge along or just off the pacific coast through late month which would funnel it over the midwest into our area keeping us in the game but just needing some luck. GEPS/EPS/CMC-E all retrograde that ridge off the coast of the pacific and funnel the cold air into the west in which case means SE ridge for our area and early spring. GEFS has done pretty well long term this year but it's hard not to be pessimistic when all of the other guidance is pointing in the wrong direction. All going to depend on who is right with the MJO progression. A shift into 4 pretty much closes the blinds late month though it get's a little less hostile come March. Hope you're right that we get one more trackable event. Those of us in SE PA are really only 1 warning level event away from touching normal, I hope we can get there. A 2nd year Moderate-borderline strong Nina, that finishes with >20" of snow would pretty be abnormal. Honestly heading into the winter I said if I get into double digits, I'd be pretty content. We got there plus saw a warning level event and a high end advisory event so things definitely could be much worse like up in the Lehigh Valley.

Euro folds to the rest of guidance on the Super Bowl threat for now as expected. Other than that though, nothing really to watch other than the temps rising to slightly above normal and a taste of early spring on Saturday for those of us around 95 and NJ with temps in the mid-upper 50's.

Euro has some snow for super bowl sunday. Temps in the mid 50's on saturday then snowing in the 20's on Sunday. Ensembles aren't enthused at all though and the GFS/CMC are both well SE and out to sea. It's a shame that the Atlantic is such a dumpster fire as the collapse of the west coast ridge continues to get punted down the line which is just plain unusual in a Feb nina so cold should be lurking nearby but without any Atlantic blocking we need really need just dumb luck. Euro is just a best case solution for the 13/14th imo. If that low amps too soon it cuts west of us and we rain and if it doesn't amp in time it slides out to sea. Dancing a fine line, I wouldn't be surprised at all if it's gone at 12z. Not really enthused for any time period after that either despite the ridge in the west hanging on for the same reasons. If it's going to snow significantly(warning level event) in February, it's going to be just a stupid lucky system. If we can hang on to that pac ridge come March though, as wavelength's shorten, could make for some fun times if the cold air continues to hang around due to that. We don't depend as much on blocking come March but we do need cold air lurking nearby for a system to tap into.

Had a dusting of snow this morning, which turned to freezing rain. No accretion though on any roadways due to how treated they already are. Looked like a light glaze on plants, couldn’t really tell. 30 F.

Didn’t even get pity flakes at the end, pity sleet shower rolling through now roads are still really wet though, even though temps are only sitting at 31 right now, if it drops into the mid 20s the next few hours, I expect black ice to be a pretty big issue overnight. Lots of ponding on the roads at least where I am.

Despite the impressive drop, looking at obs, the freezing line has barely budged southeast in the last hour+ so appears the truly arctic air is getting hung up in the Appalachians.

Damn temp dropped 10+ degrees in 10 mins down from 58 to 46.

Currently 56F and light drizzle, that warm tongue was definitely stronger than progged and I kind of expected that last night as I heard some wind gusts outside. Euro verifying actually pretty well right now wrt ice. GFS was way overdone with the progression of cold air. Pretty crazy gradient going on right now though, looks like close to a 20 degree drop 30 miles away.

Ok lets throw out the current modeling because it “sucks” so let’s talk climatology since that’s basically Ralph’s main reason for not giving up hope since it’s “climatologically our snowiest month”. Of the top 25 largest Feb snowstorms that have occurred in Philadelphia history since 1950(since that’s all ENSO data goes back) how many of them occurred in a 2nd year moderate-borderline strong Nina? 0. What was the largest individual snowstorm in Philadelphia in those said years? 3.6”. All of those years were below normal average February in snowfall. Saying “oh feb isn’t over basically only because it is Feb. 3rd and it’s climatologically our snowiest month” is disingenuous without factoring in ENSO. Hey I like snow, hope we see a good threat come into the picture and that the models are wrong and the +PNA/-EPO stays around all month plus we get the transient blocking required for our huge snowstorms… but I don’t know why I’m getting sass for basically stating what historically happens in a 2nd year medium-strong Nina’s and the models now showing those very outcomes short and long term. Every threat will be “fragile” as Ralph says because we have no blocking. We know how “fragile” set up’s work 9 times out of 10 in these parts. It isn’t a close the blinds look because of the cold lurking nearby(for now), but it also isn’t an ideal pattern for warning level events by any stretch of the imagination and the pattern as currently modeled only degrades as we head into mid month which is typical of Nina climatology, especially in 2nd year Nina’s. As I said above, an advisory level event wouldn’t surprise me, but odds are against a warning level February snowstorm for the Philadelphia metro area and average monthly snowfall as it looks right now. Hopefully the models do a 180 and we see some blocking show up and I’m wrong and everyone ends up above average on the month. It’s a weather board meant for discussing long term prospects, sorry for sharing my opinion.

MJO heads out of the cod and into phase 4 by mid month, good luck getting snow with that. There aren’t any real true threats up through mid month on the ensembles with the AO and NAO firmly positive despite the cold air delivery source from the -EPO and western ridge. Anything that amplifies will cut west and anything weaker will be shunted and sheared out south. Maybe we get lucky and one of these shortwaves in the southern and northern streams time together just right like the tues/weds “threat” but Nina February’s are historically warm and snowless for a reason. Once we lose the western ridge as the MJO heads into phase 4, I expect we are above normal the 2nd half of the month. Maybe punt was the wrong word as I suppose we could score a surprise advisory level snow from a northern stream dominant system while we have the -EPO/+PNA but I do not see anything worth honking about right now and the pattern is only going to get worse as the month progresses. If you see a time frame that you like, feel free to shout it out, outside of maybe a flukey advisory level system, I don’t see diddly but cold and dry until the western ridge breaks down and temps warm up. We really needed at least transient AO/NAO help the first half of the month and right now I’m not seeing it. Give me some reasons to have hope Ralph.

For some reason I just have very little memory of that storm. 13-14 was one of my favorite winters in my lifetime too, there were so many events to track and we seemed to get lucky every time with them working out. But looking at the storm reports, we had a .25" of ice on top of likely a 6-10" snowpack, I can see how there were some issues.

Either need that northern vort to speed up so we can get it to phase or slow down to allow the southern stream to move further northwest via the SE ridge. It's all timing. Some blocking definitely would help in this situation but if the ridge out west can sharpen a bit, that can also do the trick. Still some time for things to improve on it, but I do think it's a long shot as a flush hit.