wxsniss

GFS caved hard

That kink (green arrow)... this (0z left) is a definite improvement over 18z NAM (right), and 12z NAM was garbage:

At hr 33 look at that upstream kink at H5, wasn't there on 18z... I think gonna be a better run What's for sure, 12z NAM was an outlier

18z GFS showing signs of caving, and even so still could be better given that vorticity strength/placement but it struggles with low placement and conveyor mechanics because of that lead convection. Consensus is growing, and I still think there is potential for more NW trends.

For fun, from 3kNAM Boston area Friday morning... would be heaviest we've seen since last year:

The big holdouts we need to see cave are GFS and 12k NAM, which at the moment are in good agreement with each other but nothing else. What I see as continuing discordance between strength/placement of that vorticity and SLP on the 18z 12k NAM make me think we'll see trends for better this evening.

Given that NAM/GFS were the worst at 12z, this is a definite positive step. Still think the strength of this vorticity (now that it's held with overnight sampling) brings potential for better trends.

Yeah I take this as a positive, better H5 evolution (stronger, more consolidated further west), even though surface is a head scratcher

I think this comes in better than 12z Through 36h, vort is more consolidated, looks more similar to 12z RGEM than 12z NAM

Blend of 12z NAM/RGEM/EC/UK/CMC supports 3-6/4-8 for eastern SNE I like the Box map and think they hold steady this afternoon

Oh I understand, that was my concern as well, and why the 6z/12z meso runs today are reassuring. 12z Euro almost identical to 0z, a hair less than 6z.

Just missed you in the overnight shift, now tuning in for Euro... yeah I posted that the site going down last night was a mercy kill for all the overreacting over 1/5 0z NAM. Haven't wavered from thoughts since weekend: 3-6/4-8 for eastern SNE as a start, and now that we've survived ingest of shortwave sampling in Pac NW, I still anticipate this could trend NW in final 48 hours with potential for higher totals.

Box not weighing GFS much, looks reasonable blend of EC and mesos, widespread 3-6/4-8 for eastern SNE

Yeah 6z Rgem actually looks like it ticked a hair NW with surface track Can’t take any of these verbatim but bottomline there was no rug pulled with new data ingested at 0z

Site's back... apparently a mercy kill to minimize fretting over 0z GFS/NAM 0z EC ticked west and 6z NAM12k/3k a huge hit, 6-12" much of SNE Just missed you Jerry! We appropriately did not overreact to the 0z NAM, and while we can't take 6z NAM verbatim, it at least does not support the concern of improved sampling at 0z. Differences I see at 6z include a slightly stronger shortwave entering Pac NW and better downstream ridging / less of that scooter streak.

Just catching up to 0z stuff Yeah agree I’d dismiss NAM in a heartbeat at this time range especially vs EPS, but can’t rule out that this is reflecting better sampling of a weaker shortwave. The differences were apparent already when it was up in the Pacific Northwest. Still too early to nail the coffin.

Yep... we posted about this earlier, both from perspective of surface low position and disrupted conveyor mechanics. Majority of EPS members are west of mean, and the median is probably more informative. If the convection is not in play, the true mean is significantly more west. Watch models jump within next 2-3 cycles.

Yeah, maybe it's real and we will have a disjointed system... otherwise that 18z RGEM would have been a much bigger hit with that track. From current guidance (again heavily weighing that median on EPS which looks to be over/west of BM... and given the receding NAO and other synoptics discussed), I'm anticipating a trend northwest on op guidance in the next 24 hours. Might even see an abrupt jump with sampling tonight. 3-6/4-8 kind of range for eSNE is probably a good place to start... at some point, we'd need to see the bigger hits actually depicted on the trusted models to go higher.

All theoretical and specific to this out-of-range guidance, but that 18z RGEM could have been a much bigger hit than depicted verbatim... the convection further east is probably interfering with conveyor belt

vs. 0z: Slightly better digging shortwave... this is not so bad, probably a better hit for eSNE than 0z

EPS 0z: 12z:

Agree Frankly, any slightly outside BM tracks today make me more comfortable for our area Not wavering from my thoughts over the weekend, and still heavily weighing EPS: synoptically this is more likely to trend northwest than OTS as we get closer, especially if this shortwave is undersampled

0z Euro and GFS stepped toward each other, maybe even a little do si do Like GFS, would not take QPF verbatim especially in eSNE

Even just through hr 66 can see shortwave is digging less over Missouri... this run will not hug

Been a while (last winter) since we've had consensus for a big one... and guidance that is steady (strong signal since before NYE, 7 days) Current model weight and receding NAO make me think hugger is more likely than ots GFS today was a significant outlier EPS members: