CAPE

Its just an indication of sinking air adjacent to the strong lift in the fronto banding. The exact location of these features will be fun to track and pin down on the mesos pretty soon. Ofc we all pretty much know where the best banding will set up.

Yes I know, thus why I got "turned on" and posted it. lol.

Probably not. Looks like 33-34 at the surface is as warm as gets.

Who cares what the wonky surface maps look like. This looks interesting.

12z CMC has a more prominent primary than in recent runs.

That hard right turn of the coastal low is critical for eastern areas. Need it to happen a tad sooner/further south, instead of over OC.

The gradient along the R-S line looks to be razor sharp. If I get 4" in my yard a 10 mile drive in either direction may go from zero to 10". All comes down to the deformation band over here. Looks to weaken as it translates E/NE on the GFS.

It will, but for the lowlands it will get scoured out if that low track is tucked in for a time as advertised. At that point its a matter of how much time elapses before the colder air gets back in. A lot of elements in play there depending on one's exact location and developing dynamics. Baltimore will probably warm above freezing but it may be fairly brief compared to areas further SE. Are you in the northern part of the city?

The NAM at range is kinda like a EURO mini-me.

Good synopsis from Mount Holly this morning- 00Z Guidance retains rather impressive run-to-run consistency with respect to timing, track, and associated thermal profiles with the low, and this is perhaps helped by the progressive hemispheric pattern which tends to favor more predictability than amplified blocking patterns. Consequently despite considerable uncertainty regarding the details of this system (more on that below) do have higher than average confidence that at least portions of our area will see potentially significant impacts from this system. The one thing to point out is that the mid-lvl wave associated with this system is still over the Pacific which does favor at least some caution in becoming too confident although modern Data Assimilation is fairly robust even in regions of observational sparsity. Unfortunately (or fortunately if you look at it from my perspective) it is too early to get specific about ptypes and snow amounts, as the low`s track near to the coast will almost certainly result in some ptype transition zone. Furthermore this transition zone will likely ebb and flow as mesoscale lift (e.g. FGEN) results in dynamical cooling. That being said the antecedent airmass does look primed for wintry precipitation, with pre-storm dewpoints likely in the single digits or low- teens which should support some fairly notable wet-bulbing with the first batch of precip. The question then becomes can the intensity of the precipitation and associated dynamical cooling become enough to offset the increasing warm advection associated with the low? The next question is how robust will precipitation be on the back side of the low Wednesday night as it pulls away from the area, and cold advection begins? We should have more answers to these questions in the next couple days we enter the Mesoscale model window.

The CAD will look good at the beginning, but one thing you learn living here is how quickly it can be overcome with marine warmth when there is an easterly fetch. If we had a true blocking pattern with an ideal slow moving/quasi stationary 50-50 low, the cold would stay more locked in here, and it would probably just sleet for a time rather than rain.

Gotta have some backside love over here. Did I just send out an RR signal?

This is what eastern areas need to get some decent snow from this event.

Disagree all you want, but verbatim surface temps are mid to upper 30s along/east of I-95 for several hours.

Those surface maps are not accurate, for the umteenth time. The 6z GFS is a classic NW of fall line snowstorm, with some mixing on the SE edge. For DC to BWI points east, the surface gets toasty for a good part of Wed, and 925 mb temps are also problematic. 850s actually look ok this run. I-95 and east will need some serious dynamical cooling during the day Wed to overcome the warming lower levels, and then hope the backside delivers at night as the low pulls away from the coast.

Yeah I cant recall why that band rapidly weakened as it moved east. Kind of unusual for the big storms around here. 1996 had an incredible CCB after the sleety period. I ended up with 15" before the dry slot hit, but it sucked because I wanted the 20+ I was promised.

Not over here. It shriveled to nothing as it moved east. We dry slotted and never got more than a dusting after that.

Oh it happens in pretty much all the biggies.(excluding the 2016 debacle).This one will be on the move and mostly to the NE, so it would likely be pretty brief.

I used to be there, many years ago now...lol. Our winter storms are often not your winter storms, and vice versa. Climo snow avg here beats DC at least

Yup thats what I have been expecting all along. I am hoping for the back end thump with the deform band per the 12z op run.. Anything at the front end will be washed away most likely.

18z EPS is a touch colder at 850 and surface overall- the duration of above 0 850 temps is shorter compared to 12z. My yard only gets to a max of 41at the surface compared to 43 at 12z lol. Trending!

I thought it looked a tad weaker too. Not sure what it means later. Might be noise. Overall everything looked the same.

There really should be no "bar", or threshold for disappointment, when most of us did not even crack an inch last winter.

Looked almost the same as the Euro op to me.

Yours is coming in Jan. Its become a Nina tradition. We just need to get rid of this silly fake Nino-ish pattern. I will be chasing, as always.