wxsniss

Nice from Box... this is a healthy and slow band, 1-2" / hr incoming for Boston metro folks... this should get everyone into the 15-20" range:

Finally for Fella / SR Airglo / SBosWx and others in Boston metro... it's been like watching paint dry for improvement in flake size for past hour but we are finally tasting the edge of the meat... she's fading but there are solid 30+ dbz returns... at the rate it's moving, this looks healthy for next 1-1.5 hours at least H7 fronto:

And quickly. You can see how quickly roads get covered after they get plowed. Helps that we cooled to upper 20s too.

Agree... just probably more out between 128-495

18z RAP run gave Boston area another 4-6"... that band, though less robust, looks decent and will deliver. Intensity and flakes already improving. When all is said and done Boston area will probably end up 11-15"... nothing to complain about... is great by Sunday's expectations, and only by yesterday's 20"+ runs does it seem like a bust

Remnants of mega band have breached 495 wall... ticking east... I think by 4pm Boston area will be singing a different tune

Probably does not include the Worcester area post-deathband

We lost at least 6"... We'll still pass a foot in Boston... those bands gotta exit somehow

About as sharp winners and losers as you can get... it's coming down in Boston metro but snowgrowth is awful We know these bands must come east, question is in what state and rate

Banding delivered... 8+ hours to go?

I wish we could dissect and explain mechanistically each one of these bands, some awesome processes underway

Boston folks that mega band to our northwest looks to be decaying and maybe reforming over Worcester? We'll get our turn... all that will collapse over us, and in the meantime watch that sharp process to our east incoming...

Jay that very sharp feature is interesting, looks to correlate well with northwest edge of H7 frontogenesis?

Mega band just outside of 128 has signs of expanding east into metro Boston...

Yeah... let's relish this. The season's big one incoming. And trending better the closer we get. This is it, the thrill that keeps us coming back. Wish there was more we could nowcast... timing delay? Surface low location? Diving northern stream? Prolonged duration? I haven't found an obvious parameter to correlate with impact on the various model runs tonight, probably because the stream interaction later this morning is so complex. But regardless, the unambiguous net result in the model output is getting better and better. Gonna force myself to recharge a few hours to enjoy the fireworks. Get some rest folks, gonna be a wild day tomorrow.

Agree, ratios should be > 10:1 as we get into heaviest meat of storm

It's not like Euro to go bonkers all the sudden, but this is a great step supporting the mesos with widespread 2"+ qpf in eastern SNE

Pretty much add 0.2" qpf to 12z Euro run in eastern SNE... maybe barely a hair more compressed in west

~ 0.2" qpf added to 12z Euro run eastern SNE

Huge hit 12z-18z Tuesday... a hair west of 12z run... the west trends (NAM/RGEM/mesos) were real, toss the UK and GFS

Thru initial 12 hours looks slower and a tick west

HRDPS supports that, the band just sits and pivots over us into southeast MA for hours

Maybe... but I don't think it's simply extrapolation of current radar... the entire system retrogrades northwest with northern stream pull later Tuesday morning, and that is gonna be critical for the bigger totals. That critical aspect can't be extrapolated from radar, and that's what I'm trying to see if we can nowcast. Gonna be a thrill of a morning. You staying up all night? I'm thinking of recharging for a few hours.

Honestly hard to find something to grab onto to help us nowcast this in the next few hours Such a complex interaction aloft, and at the surface the exact location of the low does not seem to correlate with impact... at least within the next 6 hours For example by 12z Tuesday morning, the GFS is actually more northwest than the NAM... Which makes another point: GFS qpf distribution is complete garbage. I'm confident in leaning towards NAM/RGEM/HRRR/RAP at this point over GFS. Also easy to get lost because it's infrequent, but Euro steadily ticked up for 3 runs in a row.

And now RGEM Every single piece of guidance is tucking this in to more impactful, very obvious trends tonight. 1-2 feet widespread eastern SNE looking more likely.