psuhoffman

I could do a shorter one as 0z Gfs rolls in tonight if people want.

We better switch to geico…

Last comp. It’s hard to compare because the Gfs is much faster but if you take the Gfs when it had the h5 and surface low where the euro does at 90 hrs the euro is significant colder and south. Which is pretty amazing given the Gfs was at that point 12 hours sooner with less time to scour the fresh cold airmass.

One last positive and something I keep coming back too. It’s COLD in front. This has the best antecedent airmass of all the analogs we’re throwing around. That might make a big difference.

Where 18z EC it ends at 90 it’s hard to say. You would think it looks great just from this… The positives…the surface low is SE of 12z at 90 hrs. So is the h5 low. Slightly more confluence and suppressive flow over the northeast. Negatives… the h5 is more amplified, there is slightly more ridging to the north of the low and as the tpv lobe exits to our north that’s a problem. Unknowns…how the phasing is going to occur Overall I think this is a slight improvement over 12z. This is going to turn north but getting it faster and further southeast before that happens is our best bet Imo.

The differences I described above continue through 78 hours.

Through 66 it is (good). SW slightly east of 12z and less ridging and lower heights in front of it. High is slightly south. Slight improvements from what I can see. Obviously though we don’t know about the most important part which is the phase that happens later.

Of course he does it’s State Colleges biggest snowstorm ever. Lol. But it is a good analog but so is an early Jan 94 storm and Jan 12 96 and Feb 14 and there was a storm in December 2012 somewhat similar and they all had slightly different end results. He chooses the one that gave him 28” of course lol.

The ensembles look closer to what I think the op should have looked like post 96 hours lol.

Guys remember the old 5 day business planner in the 90s sponsored by Juan Valdez and Days Inn? Today the storm would have been on the very last day of that forecast. How seriously did anyone take the day 5 of that thing? Would we have dreamed of discussing the meso scale details we are right now? Yes maybe this should temper our enthusiasm some but my real point is to be amazed and how far we’ve come!

To be fair over the last 36 hours all the solutions among the more reliable globals have been between a coastal hugger and an inside runner. They all track the low somewhere through central or eastern NC and at our latitude between the Delmarva and Dulles. For 120 hours away that’s remarkably narrow goalposts imo. It’s just that we’re on a razors edge between a significant snowstorm or something less impactful. But 30 years ago we likely would be looking at goalposts between Indiana and Bermuda for the track at 5 days out! We’re now talking about details at day 5 we couldn’t imagine at day 2 when I first got into this game.

History of similar synoptic situations says something like this is more likely

That’s the track I expected too.

See my post above

Wrt the NW track. It can happen and I do expect a pretty sharp N turn when it gets captured and phases but that on the 18z Gfs is overdone Imo. But before even getting into that it was a better run. Look at 96 hours v 12z I’ll take that improvement at 96 v the wonky stuff it does later. The question is was that pretty radical NW jump from va beach to Hagerstown correct. I’d bet against it. Something like SE VA up the Chesapeake is more believable and that would have an enormous impact on the ground results in DC and Baltimore. Much less low level warm air surging in and provably would hold into snow a couple more hours which can mean 2-3 more inches. Plus sleet and dry slot v driving rain after. That’s not just a wag it’s based on the analogs to this setup where the upper low tracked similar to this and the surface low got into SE VA. The turn north was never that radical. The two 1994 storms for example, started in a similar spot and never got that far west. Both tracked up the bay or just east of it. Btw the first 94 storm had a much worse antecedent airmass so a similar track would yield better results. I think this has better antecedent conditions than the second 94 storm also. If that 96 hour Gfs plot is right I’d bet on a track through southeast VA then up the southern bay across northern DE and near Philly. That’s still west of ideal but that would avoid the spike into the 40s with heavy rain in the cities. Despite a slightly worse airmass that didn’t happen with the second 94 storm either. I got about 6” in western Fairfax county with a lot of sleet then a dryslot and temps stayed in the 30s. Didn’t lose any snow really.

Except the kicker phases and tugs the now NNW. How often is a low that tracks over Mertle Beach and Wilmington NC “too far west”. I’m starting to really rethink the order of what’s most important. Honestly it’s like 90% the phasing with the enegy behind. If the storms going to cut NNW due to that it really doesn’t matter what’s going on before that. Although the further SE start does give us a few more hours in the cold sector which matters when it’s snowing 1-2”/hr. Plus makes for an earlier occlusion which will limit the warm air intrusion west of the track. But to get a “clean” storm and a track east of the bay we really need a delayed phase or slower phase with the backside energy.

I thought he went out to Elko Nevada. Maybe I’m thinking of someone else.

I usually don’t like to do these early model observations since you look stupid when they take a left turn after but at 72 Gfs again trended east with the SW. 2nd run it reversed its early NW trend with that. Also less ridging in front of it. Positive trends there. Slightly less suppressive up over New England but as I’ve said I think that’s not the biggest factor here. Things have changed due to the timing and the energy diving in behind that wasn’t seen before. The trough is going to amplify and sharpen and this is going to pull north. Nothing going on to the northeast will stop that. It’s all about getting this SW as far east as we can before that happens. So the 2 things I’m watching are strength and location/speed of that SW. faster/east/weaker is better. And the interaction of the energy behind. Slower and later phase better there.

NAM is better. Rgem probably ends similar to the euro. NAM was the only look I’ve seen recently that made me think it could possibly get far enough southeast to track up further east.

He probably got them here http://www.raymondcmartinjr.com/weather/

Have you had a conversation with it? Maybe you can work it out.

There are a lot of similarities with the evolution but that 96 example started to amplify and got captured much later then guidance suggests here which is what saved the DC area relative to the cities further north. That’s why I said the weaker and further east we can get the initial SW before it gets captured and lifts the better. These can end well for DC but only if we can get the storm to the SE coast before it starts to lift north.

It wasn’t supposed to be when it was 100 hours away though.

I was looking at that analog this morning. 2 notable differences I found (one good one bad) 2011 had a much worse antecedent airmass in front of it (good here) but there is a lot more energy diving in behind this time which should mean a sharper trough and potentially more northward latitude gain. But I’ve not given up on a less amplified and corresponding more southeast solution yet.