psuhoffman

Yes which is why giving up now is silly

Yea but aren’t we comparing this to the previous euro not the Gfs? This was the 0z euro. It was never showing the h5 west of us like the Gfs. So if your bar for this was the Gfs ya it’s better. But I was comparing it to previous euro runs.

Temps crashing under the h5 low

Euro also has more phasing with the energy on the backside. That’s probably the worst part. As others have said if you look at 84 hours and only at what’s happening in the southeast and northeast it looks great. What really goes wrong after is what happens up over the Midwest with that energy diving in and phasing. That’s why this suddenly pulls due north v taking a more typical northeast trajectory.

It’s too early to pin details but if this takes a track like the consensus now Oakland should get hit pretty good. Places west of the Allegheny Ridges could get warm if the primary holds too long. I’ve seen that drive a warm layer up into SW PA. But typically the upslope (pretty much any wind direction is upslope along the Allegheny front) saves the higher elevations from that.

I think we’re still in the game for a very significant storm but I don’t think this has HECS 20”+ potential for 95. I don’t think anyone is expecting that. We have a -NAO but not a true block. 95 really does need a classic block usually to get those storms. Also what’s going on across Canada isn’t ideal for those hecs storms. The trough amplifying there will pull this north. To get a hecs we typically want the storm cut off from the NS there and higher pressure over the top. That’s when we get a storm to crawl to off the Delmarva then slide ENE. This is going to lift north pretty sharply. This will be a storm that runs the coast. Kinda old school, these used to be way more common than recently. And they can be pretty good but not 20” good in DC usually. The key will be how far southeast we can get the H5 before it gets captured and lifts north and how much resistance the cold can make to get a really nice WAA thump. Any deform is bonus. The 2014 storm was this type. One of the 1987 storms was and worked out to like 10” in DC. There was a similar storm to this evolution in 66 that was good in DC. There are also examples where this can go wrong if the h5 gets captured too soon. That’s why faster is better. Get it into the southeast before the trough amplified and it lifts. There were 2 storms in 1994 that remind me of this also. Early January and one in early March. Those were more ehh with like 2-4 in DC and a lot more west. This has a lot of cold on top and in front of it and that makes it a lot easier to get a better result. Giving up on this now is silly.

The pattern still looks great through day 15 on all guidance. We are just focused on a discreet event and there is nothing to add. Everything that needs to be said about the coming pattern has been said. We look to have a prolonged favorable longwave pattern that probably lasts into early February. Unless something changes, and it hasn't, now its about waiting until the waves get into range for us to discuss the details.

I was looking between hours 72 and 90. After that the storm lifts due north which is obviously not what we want and looks pretty identical to the previous run. But before that I did see some improvements. If I see something better at hour 72 or 90 I take that as a positive even if things go sideways after that. IMO the very minor improvements weren't enough this run to have much impact later on, but if that were to continue eventually it would. If we can get that upper low slightly less amplified and further southeast before it starts to feel the influence of the energy diving in behind which sharpens the trough and it starts to lift north we will be in better shape.

I was mainly focused on seeing the trend towards a slower, further west, and stronger h5 SW in the Tenn Valley stop and it did. This was the first run where that trended back towards what we want...not far enough but at least a halt in a trend that wasn't going to end well if it continued. The flow up top was a little better in front but again of the 3 factors here I think that is the least influential. If I had to rank what is most going to determine the outcome with this its 1) the strength and speed of the SW. Faster and a little weaker is better. 2) the energy diving in behind and how much it phases and or tugs the system to the NW and 3) the flow ahead of it with the departing ocean storm and TPV lobe to our northeast. At hour 90 I did see improvement from factors 1 and 3. 1 needs to continue to improve though, the GFS still has it amplifying and a bit too slow so that it can lift north a bit before we want but at least it didnt continue to get worse like the last 5 runs did progressively each time. Of course if the energy diving in behind continues to trend worse it will offset any minor favorable trends in other areas and it wont matter. Just my 2 cents.

regardless of what happens after its better at 90 than 6z was. Lower heights in front, slightly less amplified SW and slightly further southeast. The biggest thing is the NW trend of that feature has finally stopped after 6 straight runs of a steady consistent NW and more amplified trend each run we finally got a run that went the other way, if even slightly, with that feature. Again still to soon to know what that 3rd piece of this puzzle does but parts 1 and 2 trended better on this run.

Slightly lower heights in front. Actually the last few runs that has been trending better. But again I think it’s what’s happening upstream that’s the problem. Slower more amplified SW then more energy diving in behind to pull it NW. So far at 66 the slower more amped trend seems to have stopped but no improvement that I see. Still too soon to know what that last piece will do. At least on what I’m seeing. By the time I type in this I’m sure someone will already know what happens.

But that’s good. We dry slot. Any precip falling during that period would have been rain anyways.

FWIW, probably not much, the ICON is most similar to the NAM at 84 hours.

I’m sure they will be ok. Anyone who lives a place that has a median snow of 5” can’t care about it THAT much! And anyone who gets that upset when something that only happens like once every 10 years doesn’t happen has bigger problems. keep in mind the New England sub thinks this way about us! I’ve been saying the bigger factor in what was changing was happening to our west not to our northeast.

The blue seems suspect so close to the storm track but german engineering I know this is way late but my mornings are early and crazy so I actually sleep at night now. But on that icon run (and it’s something to watch for in general) is a fully matured cyclone with a surface low vertically stacked under the mid and upper level lows. That’s why the WAA cuts off to the west of the track and the rain/snow line is so close to the low. The down side to that is often a storm will start to develop nasty dry slots in the cold sector since that also cuts off the deep moisture transport and so the banding becomes mostly lift and dynamics induced.

I expect if they can somehow use AI to incorporate analog methodology and bias correction to the classic simulations we will see a huge leap. Not sure how far off that is yet. Over the years I’ve found a lot of success using cips analogs to hedge the nwp guidance.

I suppose there is a possibility it’s just random chance. I tend to think there is some causality here but it’s not impossible it’s just a fluke that all 3 operational ended up western outliers. Unlikely but not impossible and given enough chances even unlikely eventually happens.

I can’t remember a time all 3 had this stark a difference in the same way across all 3.

When is the gefs getting the upgrade. They still waiting until the short range fv3 system is ready?

It’s intriguing. It’s possible that the resolution is the culprit on the eps and geps but the issue for the Gfs is more to do with the outdated gefs. It is weird that the same phenomenon is showing on all 3 global systems. @high risk: do you know since the upgrade how the ensembles score at this range compared to the op? I think we’re still at a range the eps is slightly better than the euro op.

That minor a change is noise at that range on an op. But go back 36 hours when I think the storm was as it’s southern most point on models and look at how much the SW has slowed. I agree there has been some weakening of the flow up top but I think the slower progression is the larger influencer. Say morning the SW is over western KS when 36 hours ago guidance already has it entering the Ohio valley bumping into that confluence and getting squashed. The SW has also trended stronger and is digging much further west. That change seems a lot more significant than the relatively minor relaxation to the NE. Let’s put it this way, if that SW was as weak as models had it 4-5 runs ago and positively tilted over Indiana instead of cutting off over Kansas Sat morning I am pretty sure it would still be a non event even with the slightly less confluent flow.

It’s more than the storm is slowing down so that by the time it gets to the east the flow relaxes. There has been a slight relaxation the last 2 runs but it’s more the change in timing.

I would argue that storm happened during a transition between patterns. It was a trailing wave on a front with an initial storm that cut well NW of us. The next storm was the same situation with a cutter followed by a wave that took advantage of perfect spacing. We can get lucky with those even in just a mediocre pattern so long as there is cold lurking around, and this year we have that. The pacific driving pattern didnt really set in until this week following the cold front yesterday imo.

I don't think the ggem and GFS have the necessary resolution or physics to accurately depict the likely banding associated with the h5 low if that's what you mean.

Seeing 2/2014 high on the list doesn't shock me...I kept mentioning it because the synoptic setup very much reminded me of that.