Interesting tidbits from Mount Holly AFD-
The ultimate evolution of the first southern-stream perturbation will be what is responsible for our winter weather late tonight and Thursday. A strong anticyclonic upper-level jet streak will combine with midlevel differential cyclonic vorticity advection to aid in intensifying surface low pressure from the northern Gulf of Mexico tonight to the Mid-Atlantic coast Thursday afternoon. Intense warm advection atop a low-level baroclinic zone will aid in widespread precipitation to the north and northeast of the developing low. Meanwhile, a strong surface high will remain in southeast Canada, providing cold onshore flow for the northern Mid-Atlantic preceding the storm. Models are, as usual, too moist with the predecessor boundary-layer environment, with dew points a good 6-10+ degrees lower than model consensus today. This will be important in two ways. First, it is likely that low-level saturation requirements will delay precipitation onset in our CWA, with snow not likely to get going in earnest until near or just after daybreak. Second, models are likely too warm at the surface, especially during the main "thump" of precipitation during the morning hours. Sided with colder guidance here.
With models trending slightly northward with the warm-nose influence on precipitation type on Thursday, our inclination was to be a little less aggressive than consensus in this regard. No question that the strength of warm advection will be intense, likely leading to a veritable sleet storm in a good chunk of the area as the event unfolds during the day. However, there has been a tendency for higher-res guidance to be a little too aggressive in shunting the warm nose to the north this season. Of course, there has also been a tendency for northwest shifts in the snow/sleet/freezing rain geographical distributions within 24 hours of the event (playing out once again with today`s guidance). It will be quite interesting to see how the 00z solutions play out, as run-to-run variability has been diminishing confidence in the forecast for this event considerably.