RU848789

So Mt. Holly updated their CWA map, but not the better map showing neighboring areas - anyone seen that yet (not on FB/Twitter/NWS pages)...

Blizzard and Winter Storm Warnings Expanded The blizzard warnings were extended about a county inland by the NWS (counties in orange) and those watches for counties in NEPA were converted to warnings (pink), as the NWS clearly has more confidence in more snowfall making it that far inland so they upped snowfall for everyone especially west of 95. Below is a bulleted summary of the blizzard/winter storm warnings which is easier to digest than those long text strings the NWS puts out. Hopefully we'll see a new NWS map soon, as snowfall amounts have been increased, as per these warning amounts. Specifically, the warning for Somerset/Middlesex/Mercer is for 16-20" of snow and the map had us at 12-16" (and this goes for everyone). The links below have the full text for all of the warnings. Blizzard Warnings from the NWS-Philly and NYC Blizzard Warning for Atlantic-Cape May Counties for blizzard conditions with total snow accumulations between 12 and 20 inches and winds gusting as high as 50 mph. Blizzard Warning for Gloucester-Camden-NW Burlington-Cumberland-Counties for blizzard conditions with total snow accumulations between 14 and 20 inches and winds gusting as high as 45 mph. Blizzard Warning for Monmouth-Ocean-SE Burlington Counties for blizzard conditions with total snow accumulations between 15 and 20 inches and winds gusting as high as 50 mph. Blizzard Warning for Morris-Somerset-Middlesex-Mercer Counties for blizzard conditions with total snow accumulations between 16 and 20 inches and winds gusting as high as 45 mph. Blizzard Warning for Passaic-Hudson-Bergen-Essex-Union Counties for blizzard conditions with total snow accumulations between 12 and 18 inches and winds gusting as high as 50 mph Blizzard Warning for Westchester-Manhattan-Bronx-Staten Island-Brooklyn-Suffolk-Queens-Nassau Counties for blizzard conditions with total snow accumulations between 15 and 20 inches and winds gusting as high as 55-60 mph Blizzard Warning for N Westchester-Rockland Counties for blizzard conditions with total snow accumulations between 11 and 15 inches and winds gusting as high as 45 mph Note: blizzard warnings are also up for Delaware and Connecticut, as well as Rhode Island/Mass (not including those details) Winter Storm Warnings from the NWS-Philly and NYC (very close to blizzard conditions, looking at the winds) Winter Storm Warning for Carbon-Monroe-Berks-Lehigh-Northampton Counties for total snow accumulations between 8 and 16 inches and winds gusting as high as 45 mph Winter Storm Warning for Delaware-Philadelphia-Chester-Montgomery-Bucks Counties for total snow accumulations between 14 and 18inches and winds gusting as high as 40 mph Winter Storm Warning for Sussex-Warren-Hunterdon Counties for total snow accumulations between 13 and 18 inches and winds gusting as high as 45 mph Winter Storm Warning for Salem County for total snow accumulations between 14 and 18 inches and winds gusting as high as 40 mph https://forecast.weather.gov/wwamap/wwatxtget.php?cwa=PHI&wwa=blizzard warning https://forecast.weather.gov/wwamap/wwatxtget.php?cwa=PHI&wwa=winter storm warning

Ok, time to up those accumulations - the King is on board! Best Euro run yet.

A few commnts on the NBM. Some think the high amounts are all due to the GFS/NAM being part of the blend and that's partly true, but snow ratios are also part of it as can be seen by just looking at the QPF vs. snowfall maps, as there's nowhere with >2.4" of QPF, but many locations getting >24" of snow even along the coast and inland with maybe 1.5" of QPF. The NBM table above says they use a combo of max temp aloft (Kuchera, I assume) and the Cobb method for generating ratios. So those 10:1 maps are likely underestimates.

Personally I'm good with the NWS going with the "average" model camp (8-12" NW of 95, 12-16" near/along 95 and 16-20" for the coast) from a public safety/trust perspective, since going with the low end model average and having something near the high end verify would have people not quite ready for an historic storm. They can easily bump down from the average camp if things trend that way before the storm starts and easily bump up towards something historic (the 10% high case) if the low end models bump up significantly. I am a bit surprised their 10% low end case is so low - that implies they still think there's a worst credible case for the system to go back to the Euro 2 days ago. That would kind of suck.

Nothing is tougher to remove than sleet, especially when it falls at 15F and freezes solid if people didn't remove it soon enough (I did, but many friends didn't). This won't be a picnic though, either.

AIGFS 18Z snow map? TIA. And has there been a WN2 lately?

We still have 2-3" of heavy snow/sleet on our entire property (over 1" since 1/17), although it's no longer topped off with a hard frozen sleetcrete layer anymore as that has softened up from the rain/warmth. Should still be >1" on Sunday and then boom!

They updated that but not the main map yet - actually they just did update, but it's only through 7 am Monday - was wondering why the numbers looked low. I wish they'd only ever issue maps for full events - these partial maps are misleading.

That's an HECS like the GFS. Wow! Thanks for posting the AIGFS/Weathernext models which TT/Pivotal don't have.

Thanks. Ignore the point and click when they're at odds with the issued snowfall maps. They'll update soon. Also if you go in to the hourly weather graphic it shows 4.3" of snow for Perth Amboy.

More pretty pictures...

As I mentioned earlier, the NWS said in their AFDs that they were closely following the NBM, so given that the NBM has taken a decent bump upwards (maybe included the NAM already) at 07Z, I'd expect watches to go up for anywhere that is at at least 6" on that map, which includes this entire subforum basically and the Philly subforum too (note that this map includes previous snow from the Catskills northward).

Yes, we've been NAM-ed. Huge to see even if it's a bit out of its range (the important changes were mostly earlier).

That's incorrect. NWS forecast for NB through NYC is 4-6" through 7 am Monday, which would be 5-7" through the end of the storm at 1 pm Monday, assuming use of the NBM (which they said they followed closely). See my other post with the maps and such.