wxsniss

I'd love for that to happen... but gun to head, I'm still not confident enough of that. WV looks good but lots of guidance has that current energy tugging east or remaining really scattered. Awesome nowcast event.

My thoughts... tough forecast, we're watching a vorticity mosh pit try to clarify in a dominant direction... next 6 hours of nowcast will tell all... and with H7 closing I went more bullish NW compared to most guidance...

High bust potential with this either way. This is a nowcast event if there ever was one. A big driver of the event is buckshot small pieces of vorticity, and everything depends on how these consolidate and track overnight. IMO (and I've been staring at this on off since Jimmy's post this morning), nothing glaring in current water vapor to indicate which way yet, but the next few hours are critical. There's no obvious intense convection far east (purple circle below), and most of the activity is over NC/VA which is good (2 black circles below). But it's really the next 8 hours that are critical. In the big hits last night, activity in the left black circle dominated and the right black circle kind of diminished or circled north. In the more east hits, activity in the right black circle persists and tracks further east.

Can't see H7 Verbatim qpf (to compare to 12z, ticked less further NW but more southeast MA to Cape): 6"-12" just south of Boston to RI border to canal 12"+ canal and northern Cape

18z Euro about same as 12z, ramped up for coastal areas / Cape

I think at this point we would like to see less organized activity off of NC in favor of the energy inland emerging from TN... the activity currently off NC is what would tug this east Our main show surface low develops of VA/NC around 4z-5z tonight

Funny I've intermittently been doing the same... and trying to decipher upstream signs that this is gonna go one way or another. James gets bashed alot (often appropriately), but I'll give him credit for reminding me to look earlier this morning. I totally agree... mesos have been emphasizing the stuff emerging from NC, but the stuff over Tennessee valley looks much more robust. Critical water vapor window I think might be ~ 5z-6z Saturday to get a better idea of where this is going. If the best activity is just off of Delaware, we are in business. If it's way off the coast, we get tugged more east.

QPF may not have improved much, but vorticity is more consolidated, better kink at H5, and closes off at H7 Take home: the trend towards an eastern fade on some 6z-12z guidance has stopped

12z Euro / GFS actually pretty close Consensus for 6-12 northeast MA down to CT/RI border, 4-8 Worcester east and most of CT

Euro / GFS blend ftw? Lends credence to the meso's /hi-res models getting a little confused by the buckshot diffuse vorticity

Not even looking at qpf... vorticity is more consolidated and tucked... this is a better look for sure

Yeah I posted his sub Wankum's 11pm forecast... 1-3 / 3-6 straddling Boston. Looked like a very conservative forecast after the 18z-0z party, but maybe he'll get the last laugh. This is not an easy one.

This is a really tough forecast. A ramp up or a Messenger-fade both seem possible, and I'm really not confident in one way or the other. Vorticity is buckshot diffuse and models are not handling it well. Overall H5 setup kind of favors Messenger-style fade, but we do have a digging kink. I think 4-8" Boston southeast / 3-6" northwest is a good starting point.

Sorry, a more amped version like he alluded to Basically 4-8 eastern 1/3 of SNE, as a starting point

We need to over-react less to each model run... and I should not have used the descriptor "huge", that was a mistake. Jerry's right RGEM has been terrible this year, so I wouldn't over-react to that alone. I like Ray's map as a starting point. It has good support from Euro which has been steady outside of the 18z pan-model jail break. I still could see this amping more... just needs vorticity to consolidate better rather than shunting east, something that the models don't seem to have a good handle on and will come down to nowcasting later today.

I never took the 6z RGEM run seriously, totally coked out starting point 12z RGEM settled on a 4-8" across most of eastern SNE, still a big hit and consistent with Euro

Don't have totals yet but I'm eyeballing 4-8" for eastern SNE Question is does this trend continue, and I don't think that's unrealistic... the vorticity is kind of buckshot diffuse, and I think alot of this will come down to nowcasting this evening

12z RGEM definitely not as coked out as 6z, but still a big hit (i.e., warning) for eastern SNE... 12z on right Trend so far at 12z has been to tug this further east...

12z RGEM a little toned down from 6z, tugged further east, but still a huge hit

Agree, and there is definitely a little chicken-egg feedback going on as you commented. 3k 12z NAM also has a buckshot diffuse vorticity. Jimmy's shortwave image is actually useful in favor of a more consolidated vortmax, so despite what guidance is showing, that would argue for a more consolidated and tucked low.

Don't think it's just chasing the convective blob here... you can see differences already by 14 hrs, vorticity is spread out more east and so later does not wrap in Not an unrealistic solution, eSNE widespread 4-8" instead of 8-12"+

Definitely a less amped 12z NAM run... you can see as early as 18hrs (6z Sat) the vorticity shifted a little further east, and H5 is slightly flatter and less kinked

Thanks Will That's actually more consolidated than some of the earlier runs that had a separate vorticity lobe further out (like the on the Meh vs. Good GFS comparison I posted last night) As for the upstream indicators of Meh vs. Good...? It seems on the Meh runs, the energy out of the N Gulf emerges further south and shoots more east after it exits Carolinas, whereas on the good runs it tracks more north and curls into the shortwave on the Good runs. This is around 6z Saturday. And further upstream? Hard to identify a consistent difference. Box AFD was commenting that the N Gulf energy was slightly faster than 0z guidance initialized so they preferred Meh, but that was before all the 6z guidance.

Where do people get 6z/18z Euro H5 vorticity? Can’t find it on weathermodels.com I like the 12k/3k 6z NAM. Somewhat more ramped up than 0z/6z Euro, not as coked up as RGEM. I’m surprised there are no watches. Even the worst guidance brings warning SEMA. There’s a good kink in the flow... too much weight on seasonal progressive shred.

For sure, just putting up the verbatim qpf for easiest run to run comparisons This is a good system for deformation banding, maybe roughly northeast MA to between Worcester and 495, obviously will depend on where this tracks I'm still puzzling over the 18z jump, can't be coincidence. And not characteristic of Euro to make such a big jump. I would've expected the progression of Euro solutions to be more like 12z --> 0z --> 18z Still think we end up warning+ most of eastern SNE