SACRUS

34 / 34

grass slowly whitening real accumulations by 4:00-5:00 for here then hopeful 1.2-1.5 LE for 10-18 here.

Snow mixing in here now 35/34 so far about 0.10 in the bucket ahead of the change over probably cut through another 0.05 or 0.10 before starting to accumulate.

2PM on the HRR

 Tool

Band locationRadar → HRRR

Snow rates: HRRR

Band confidence: HREF

Temps / p-typeObs → RAP → NAM 3k

CAD statusObs + RAP

6 minutes ago, Nibor said:

It’s a hybrid of sort but there’s always nuances with these storms. 

Miller s Maybe this is a C but i was leaning B

3 minutes ago, Northof78 said:

What are models progging surface temps for tonight? 30/31F or lower or hanging around 33/34F for the main part of the storm? Huge difference there. 

down as low as 28 into nyc mainly hovering 29ish

UKMET

Snow

3 minutes ago, MJO812 said:

Coast still looks good. Banding is tricky to pinpoint.

yup case in point if the gfs was off with this band by 25 - 30 miles - major implications - the storm will do what its gonan and wants to do - no model especially global will hone in in this range with the banding which are paramount in these coastals

1 minute ago, Jersey_Snowhole said:

12z gfs drastically cut totals in the metro.

would rely more on hrrr/rap / nam 3k and rrfs and radar later with the deform band - GFS keeps the heaviest s and east of NYC

Last WPC update QPF for this storm 

The RRFS which is set to replace NAM/ HRRR beefed up / its snow alogrithm is odd

QPF

Snow ratio undetermined

Just now, MJO812 said:

Cranking 

Thats through 3am more to come , maybe half way or more

I added my notes and experience with these miller b type storms systems into cpgt to summarize it:

 

• Miller-B storms are defined by a late coastal transfer, where a secondary low forms near the Delmarva and rapidly takes over from the inland primary, setting the stage for sharp impact gradients.

• The heaviest snow almost always occurs in the deformation band, where strong frontogenesis and mid-level forcing lock in for several hours, producing rates that far exceed model averages.

• Banding typically pivots northwest late, meaning early offshore or marginal solutions can still evolve into significant accumulations closer to the coast.

• Cutoffs are sharper than in Miller-A storms, with 20–30 miles often separating warning-level snow from minor accumulations or mixing.

• Winners are determined by band residence time, not storm totals—locations under a persistent band can double surrounding amounts.

• Losers are often directly south or east of the main band, where dry slotting, subsidence, or warm air intrusion sharply reduces snow despite proximity to the low.

• Small timing errors have outsized impacts, as a 6–12 hour difference in transfer or band pivot can completely flip outcomes for places like CNJ and NYC.

• Thermals and coastal fronts dictate who stays snow, with heavy rates often overcoming marginal surface temperatures in the core of the deformation zone.

• The biggest totals usually exceed early forecasts, because mesoscale banding intensity and persistence are rarely fully captured until the storm is underway.

THis is when (4PM) most goto snow and it should start coming down and accumulating on cars/etc as temps cool and intensity picks up

Coldest temps i see on guidance for NYC at height of the storm around 3AM
29 hours before and after

This is whats lost to rain/mix lesser rates which the nams accounted for

1 minute ago, BoulderWX said:

You can see the western edge moving east on many of the models. Not as expansive of a precip field on the recent Mesos. I’m riding the razors edge here between a significant storm and something more run of the mill

It'll be all about the banding

2/22 NAM 3k 

2/22 12z NAM
 

4 minutes ago, CPcantmeasuresnow said:

There's actually 68, 10 inch or greater snowstorms in NYC since 1870. Did you cut off after a certain date?

It was a top 40 *(most recent)