psuhoffman

Yea but with a primary unto Pittsburgh and a secondary near Annapolis it wouldn’t matter. But the exact track at day 10 doesn’t matter either. The ingredients we need are all there. We just need them to come togterget properly.

But do you know how rare what you just described is??? Ok so in the last 30 years there were only 18 storms of 6" or more at DCA. That is an average of 3 every 5 years...we have had 2 in the last 5 years so we are only 1 storm short of "normal". But the truth is those storms come in chunks during rare winters where the pattern is great. 4 times in the last 30 years DCA had multiple 6" snowstorms in a single year. 3 times in 1996, 3 times in 2002-3, 4 times in 2009-10, and 2 times in 2013-14. In the other 26 winters DCA had 6 total. So basically once or twice a decade we get a super rare great snowy winter where we are likely to get multiple 6" snowstorms....and the rest of the time we are very likely not to have any at all and if we get one its just a fluke, and only happens once every few years. Again...the problem is everytime we get a winter like the 26/30 crap years where we either get one lonely big snow or none you call it an anomaly when in reality that is just our normal. Our normal is crap. BTW if you eliminate the 6" storms that happened in March or were barely 6" followed by rain or an immediate warm up that melted it all within 24 hours DC only had 13 of those storms in 30 years... And if we take out 1996, 2003, 2010, and 2014 as the 4 "fluke" snowy years...only 3 such storms in the other 26 years. Basically, to summarize...every 7 years or so we get a fluke winter like 1996 or 2010 where its cold and snowy and we have results more typical of New England than DC...and in those years we tend to get multiple snowstorms like you describe. The other 80% of the time... we go several years between such storms...and when they do happen they are often flawed with a warmup right after or happen in March. What you are describing is a very rare thing in DC.

@RevWarReenactor with it being a holiday weekend if the resorts areas are booked you can still easily drive up from Rutland area. 20-30 mins. They keep the roads good. And there is stuff to do up at Killington. Some hopping bars with live music.

@RevWarReenactor keep an eye on today’s trends but based on recent runs VT might be your best bet to see a lot of snow otg and not worry about mixing. This total includes a 3-6” storm the next 48 hours but still. Im using the op because the kuchera shows the ratios in VT will be good. The 10–1 maps show they get 3-5” from the weekend storm but it’s more likely to be 4-8” or more plus they have snow on the ground already. And there are lodging options near the ski resorts. It’s only another 1-2 hours from Albany. Check out lodging near Killington, Okemo, Stratton. Stay out of the valleys like Rutland, they get a nasty shadow effect. I’ve been there when Killington gets 20” and Rutland had 4-5”. That snow south of Albany is mixed with ice and subject to further cuts if this keeps trending north. And those places have no snow currently either. Just my 2 cents. Good luck!

places in Vermont just had some snow, and are getting 2-4" before this event...then will get more. So if you are going just for snow...going another couple hours to see a LOT more snow makes sense imo.

When I said Quebec I meant QUEBEC...yall thought I was kidding.

Here is how the look for around day 10-12 has shifted on the GEFS (EPS is similar). Now this time we are comparing a day 15 look to day 10..(last time it was day 10 to 7) so the shifts are going to be a bit more drastic...but still the large scale longwave pattern wasn't awful. GEFS from a few days ago This was a very cold look, big EPO ridge with cross polar flow directed right into the eastern US. But it's also a dry one, and I mentioned that a few days ago when this look was being tossed out. This was likely to be very cold but very dry. The other 2 major features were the PV situated across the NAO domain across the pole into the Kara region, eastern trough, trough in the Pac NE of Hawaii. This is how it has shifted So again it was too far west with the pac trough...this shift pressed the epo ridge into more of a Hudson Bay ridge. It was correct with its NAM depiction and the trough in the east. Now this has a positive and a negative. It cuts off the cross polar flow, so this is a much less cold look. But this is also much more likely to get something to amplify into the southeastern US. That blocking ridge across Canada will cut off arctic cold but there is a shot of cold into the east ahead of this...and so long as that is trapped under the block and not scoured out that usually is good enough in January. Ideally I would like a 50/50...that could end up being the big issue here if too much ridging in the northeast allows the system to cut... but this still has potential imo. This is a composite of 16 warning level snowfalls at BWI with a Hudson Bay centered ridge. The obvious thing missing is the 50/50 low. But that is a composite, not ALL 16 of those had a 50/50, but most hence the mean. But at this range a feature like that could be missed, perhaps an unseen vort next week, Ralphs clipper, can bomb out into the 50/50 space, or perhaps the day 11 storm does cut but becomes the 50/50 for the day 14 threat. Either way, this look is way closer to a big snow look than the one a few days ago. It's not nearly as cold...and it could end up a rain look also...but you have to play with fire to have a nice BBQ! If you did want a week of frigid cold dry weather...I apologize, things are not moving in the right direction for that.

@Ji @Ralph Wiggum Was going to post this earlier this morning then got distracted with work. But this is an example of how the overall long range guidance was right...but discreet features within the longwave pattern that are not discernible at long range will determine snow/no. For next week...the period Monday to Thursday...from long range it looked promising Ridge bridge across the top, western ridge, eastern trough...this look could definitely work The overall longwave pattern was pretty close but some details have shifted this to an unfavorable (for us) look Still have the ridge bridge over the top and eastern trough but the system crashing into the Pac NW is shifting the western ridge too far east and that shifts the eastern trough too far southeast...this is now a good look for a possible snow for places in the southeast, maybe the outer banks. Doesn't mean they get snow...but they have a chance which is super rare in itself. The slight error on a specific feature that will not be resolved at day 10-15 shifted this from a very good look for snow to a cold/dry one for us. The guidance wasn't wrong or bad...we just can't see the details that will determine our fate wrt snow from that range. Only the general longwave pattern. Even in a good pattern we need luck with the discreet features. Only a relatively narrow area will actually get snow in any given (short) time period. The coverage of snow with a storm isnt that large typically. Or the difference between a wave amplifying or getting squashed isnt that big on a hemispheric pattern scale. Too many people assume if we get the good pattern it means we get snow. Not the case.

There is "slightly" too much ridging to the northeast, the h5 trough amplifies slightly too far west, the airmass is slightly too warm... a lot of very small imperfections combine to ruin it on this specific op run, but like I said yesterday this setup continues to be a "Ohio cow's fart in the right direction" from being a big snowstorm for us. There have been plenty of similar situations where at LONG leads the guidance thought what ended up a big snowstorm was a cold rain event. I will take my chances on this setup. It's the best one we have had yet this winter.

Thank you! I just wish I spent more time explaining why it was going to snow instead of why it wasn't...

That precip you are looking at isn't the main result of the primary low back in Wisconsin though. It's the result of the WAA , which is primarily driven by the low and mid level winds ahead of the trough into the cold air. This was the last really good run of the GFS from 6z yesterday and look at where the mid level winds were directed.... now look at the primary low location Now look at last nights crap awful run....the primary low is much further southeast...but it doesn't matter Because look where the mid level winds that will be the main culprit for any WAA precip have shifted The flow that was directed right into us on the guidance that showed a healthy WAA thump of snow is now directed well to our northwest and that is because of the increase in the ridging and sharper trough alignment not the primary low. The precip from the primary low is irrelevant to us, by the time that gets here we will have lost the mid levels and likely the surface. Whatever snow we get will be from WAA out ahead of the primary system. But the winds that would cause that are being directed away from us by the ridge/trough alignment. We would need a radical shift in the primary low track for that to due us any good...yea if it did track through central Indiana into northern Ohio that would likely redirect those winds towards us as it would indicate a radical shift south of all the features, including the mid level wind flow. But it would be the shift if that wind flow not the primary that would help. And that is a HUGE shift...were talking like 150-200 miles in only 3-4 days. Not sure how likely that is. Seeing the mid level winds shift back to a more favorable configuration is more likely...but only slightly. So a shift south of the primary if it is associated with a weaker ridge and flatter solution would be good...but a shift in the mslp absent the improvements we need at the mid levels ahead of the system would do us no good really unless its a 250 mile shift in track.

the TT snowfall maps count "ice" as snow. It's a known thing...so its kinda annoying when people post that map and say "haha look at how stupid this is showing 15" of snow when its going to be like 2". The model is NOT showing that. Those maps have a major flaw. That's why we call them "clown" maps.

Wernt the Models recently showing a big nao in the 6-10 day window? Briefly and it’s still there next week but it’s a wasted window (probably) because the trough axis is too Far East. Was about to post on that. Looks like a great chance for the southeast coast though.

What is frustrating is we keep cycling between the PAC and ATL taking turns crapping on us. The pac looks to get pretty good for the next 2 weeks but the scandanavian ridge suddenly flips to a trough which allows more ridging to shift across into a position that could muck things up. It's still not a bad look...but "one thing" keeps going wrong. The thing is..that is normal. Because to get snow we need so many more things to go right than wrong...that more often than not one thing will muck it up. Kinda like a golf swing.

Before I start a weenie stampede I should clarify that this setup does not have the upside those other storms I referenced did. I was purely using the airmass similarities. Without Atlantic blocking this storm would be more progressive. If it rides the coast it would likely blast up the coast not stall and dump on the mid Atlantic. But those can still be very good snowstorms. Just usually not 2 foot HECS ones. And it would have a higher chance of cutting. And if it did stale cold won’t work. I was simply saying if we get a 990 low up the coast with a perfect track I do not buy the rain scenario.

I will say this...if we do get a miller a storm with a perfect track (barring bad luck with a NS vort like the HH gfs run) I don’t buy the rain idea. I said the same thing when the Jan 2016 storm first showed up around day 12 and was warm on guidance. Euro was showing a perfect track gulf low rain storm when it first came into day 10 range. And I said BS. If it goes down like that in January stale cold will be good enough. Feb 5 2010 also was warm at really long range. Same reason. Same result. History/climo says stale cold stuck under a Canadian ridge is good enough with a good storm track in January and February. Climo for an advertised pattern beats nwp output range most times. We need the nwp to help with pattern recognition but I’ll take what history says should happen with the details.

Good luck analyzing a clipper at 150 hours. The day 10 stj thing is what I’m talking about. You’re right about discreet things not showing until inside 4/5 days...but the problem is it’s hard to spend a lot of time analyzing something that hasn’t shown itself yet. Could an unseen vort pop up in the cold window next week? Sure. It’s a pretty suppressive flow though. But maybe that relaxes some. Problem is that’s all pure speculation with no meat to analyze.

Go back on TT and cycle through the gfs and euro runs the last 72 hours and compare the “snowy vs not” runs. The strength and track of the primary have no correlation to our snow with this setup. The runs that had less ridging and this a more elongated trough to the east of the low to direct the winds ahead of the system more east into the mid Atlantic (hence WAA) were good. Regardless of the primary low location. The runs with more ridge and sharper trough were bad, regardless of the low. Now if you adjusted the low far enough south it would matter. But that would have to be a huge adjustment. Moving it 50 or 100 miles won’t matter when it’s cutting through Wisconsin. An adjustment from Green Bay to Milwaukee won’t help.

I thought that too (and there is some of that) but even some of the members with 990 lows off the coast that bomb us with precip are just rain. You see anything under 240 worth focusing on?

I am legitimately perplexed by the lack of hits day 10-15 on the eps and gefs given the h5 look. Even when you examine the mslp and precip...it’s a coastal track. Not cutters. And it’s not warm. Not really cold but below normal the whole period. It looks great. Then you look at the individual member output and it’s a bunch of 36 degree rainstorms from a perfect track miller A storm! Now I see the “wart”. The ridging in Canada gets centered too Far East which cuts off the cross polar flow so we end up with stale cold across the conus after the initial dump next week. But that setup (ridge bear or just west of Hudson Bay) has been a staple of mid winter snows here. In my study it was the second most frequent feature to an NAO block to signal snow. Like an NAO pattern it’s not an arctic cold look but it’s January. Prime climo. Stale cold air should be good enough. It was in Feb 2010. That was the same general airmass, leftover cold from the dump late January that was cut off under blocking across Canada. It was a garbage airmass by Feb 5. Would have been 45-50 degrees if it was sunny with no snowcover. But it worked with storms tracking under us. I know I’m ranting but my god that pattern should work. Maybe it will and guidance is off by a few degrees at range. I hate to bring you know what up with you know who around but seeing a pattern that has been bread and butter for us in the past look “just a couple degrees too warm” in prime climo (literally this is the coldest/snowiest part of the year) really is frustrating.

The longwave pattern still looks as advertised. Problems are with details that cannot be seen in long range.

@frd still no idea what he meant wrt the IO standing wave in 2/3. That’s a cold look in February.

The primary is south but that hadn’t mattered at all on past runs. It has no WAA surge to the east. Precip is nowhere near us at 12z. That run won’t end well imo.

@Bob Chill looking at h5, slp anomalies, precip, temps, I expected to see a lot of hits on 18z gefs...but no. A couple but when I saw the lackluster snow mean I checked out the members. A lot of coastal scrapers or OTS. A couple hits. But the majority that come up are perfect track rain storms according to the members. Odd. I guess a 36 degree rainstorm would still show up as a “below normal day” becauss we suck that much. Just not the profile of a rainstorm. Seriously this is a rain look now...I have a hard time buying that

Strengthen the western ridge or shift it east some...weaken or shift the eastern one west, and you end up with the upper low where we want it. Not a big change at day 12.