CAPE

The subsidence adjacent to these bands can suck. Kinda stuck in between 2.

6z GEFS suggests a favorable track for frozen for much of the region, and would be a good outcome for eastern areas. EPS is a bit more of a coastal hugger that would be more rainy/mixy for the lowlands and favor the fall line and NW. CMC ens is somewhere in between.

32 with steady light snow here. Getting fringed by the nice band just to my north.

Timing is always big. We don't need or even want a super positive PNA though for a big snowstorm. The more important trifecta is the one that produces +heights straight across the HL region to our north.

Just a note about the teleconnections currently: -AO, -NAO, and yes a -PNA. WPO is also significantly negative. Southward displaced TPV lobe underneath that HL block. Pretty classic h5 look for a MA winter storm, with lots of red up top.

33 with moderate snow.

Nice discussion from Mount Holly. Mention of blizzard conditions for coastal DE. Spectacular satellite imagery over the East this morning as a strong area of low pressure comes together to our southwest. Just a classic eastern US winter storm presentation. A blossoming shield of precipitation is now overspreading the local area. A major winter storm will affect southern portions of the area over the next 18 hours. The main change to the forecast overnight was an increase in QPF, and by association, snowfall, for areas previously within and that were just north of the previous Winter Storm Warning. The QPF increase is almost unanimously supported by the last two cycles of global and hi res guidance, and translates to an increase in snow totals. The most difficult portion of the forecast remains the northward extent of precipitation shield. Even many of the recent model runs which increased QPF across the south generally didn`t move the precipitation shield north much. The latest blend does bring amounts up somewhat in the I-95 corridor. However, there is likely to be an exceptionally sharp northern cutoff to accumulating snow, probably even sharper than the latest forecast, which as it is has a much sharper than normal gradient. Even across, for example, Philadelphia County, it would not be surprising to see a significant difference in totals. And for northern portions of the area, it will simply be a cloudy and cold day with perhaps some flurries. Confidence in snowfall is much greater for southern areas. It is clear now that a swath of heavy precipitation will overspread the region. Extreme frontogenetic forcing is allowing precipitation to expand in coverage and intensity to our southwest, and this will only continue today. While precipitation is beginning as rain in some places, temperatures are continuing to cool behind yesterday`s front, and a flip to snow will occur. One possible exception is far southeast Delaware, where rain or mix could hold on for longer. Amounts were reduced a bit there. Otherwise, a large stripe of 8 to 12 inches of snow is now forecast, and can`t rule out some localized amounts a little over 12 inches. Snowfall to our southwest has generally been over-performing, and this trend could continue into our area. Snowfall rates could easily exceed 1 inch per hour at times this morning, perhaps 2 inches per hour. While snow ratios overall will be less than 10:1, these rates will quickly overwhelm the warm ground conditions left by recent near record warmth. These snowfall rates could persist for several hours this morning and early afternoon. Banding features are certainly possible within the heavy snow shield, leading to some local variations. Eventually, precipitation will end from west to east late this afternoon and this evening as the area of low pressure moves out to sea. Northeast winds will become strong near the coast today, gusting in the 30 to 40 mph range for several hours. With heavy snow occurring through this period, a period of near blizzard conditions is possible for areas such as Sussex County DE and portions of Cape May and Atlantic Counties. A Blizzard Warning was contemplated, but am not confident enough in criteria being met for more than brief periods.

Updated forecast here is 8-12" with a mention of locally higher amounts.

34 with a light coating of wet snow at 430 am.

47

Have you hit 100 posts about the HRRR NW trend yet today? So odd the modeled heavy snow area hasn't reached Erie yet.

Quite a bit of dirty talk in the WPC Heavy Snow Discussion- The guidance this aftn have continued to trend stronger, a little slower, and more NW with this system. The exception is the NAM, but this model seems to be initializing a bit too far south compared to reality and is not preferred. This trend suggests another uptick in snowfall potential which is reflected in both WSE mean/NBM 50th percentile, as well as the high end potential of the 90th percentiles of these same ensemble clusters. While antecedent conditions are quite warm, and many places may start as rain before changing over, rapid CAA behind the cold front will quickly transition rain to snow in many areas. This CAA will be aided via impressive ascent within a pivoting deformation axis to drive intense dynamic cooling of the column. Although SLRs will vary greatly, starting very low and then increasing with time as the column cools, notable overlap of -EPV* and ThetaE lapse rates near or below 0 suggest CSI or even upright convection (thunder snow) within the best deformation. This could produce snowfall rates of 2+"/hr, which is reflected both by HREF snow probabilities and the WPC snowband prototype tool, with the highest chances across VA, MD, DE, into southern NJ. It is these rates that will help overcome the low-level warmth and hostile antecedent conditions to produce heavy snowfall.

Not on the 18z run friend. And wrong thread.

Just because I happened to be looking at it at this exact moment, here ya go.

Good stuff. CC is not bad, and it's right down the street from the park. I like the UFO NE DIPA.

Been out enjoying the Spring-like day. Lots of people out at Terrapin. Stopped and had a flight at Cult Classic. So what did I miss? Obsessions over bumps north? south? Snow-eating mud concerns? Forecast here is 4-8". Seems about right. 58 here. Defo feels like snow.

GFS has locked in on the big storm idea for 4 straight runs now, each incrementally better. Gotta go with it.

Have not seen much concern for that yet, other than at the beginning. Once the column cools, given the somewhat suppressed/offshore track of the low, it should remain all snow. Best fgen still progged there, so even with more marginal surface temps for at least part of the event, a longer duration of moderate/heavy snow in those areas should get it done. I might have placed the heaviest snow area slightly further north.

Looks reasonable to me considering the antecedent conditions and the progressive nature of the pattern. You really buy those pretty WB clown maps?

This is about the time where I quietly sneak out of the main thread lol. The 'model analysis' just gets more unbearable from here. So much talk of bumps here and bumps there. Ravens94 and the goddamn HRRR.

This should be fun for you in your new and improved snow climo locale.

I did see that. The enhancement due to terrain is a thing. And Mount PSU will have high ratio snow start to finish, so he is good for at least a half foot of fluff even if on the northern edge.

You're right in general, but not sure this is one is going to be able to climb the coast enough to place it in the usual spot.

++WDI