CAPE

12z EPS is trying for the late week thing.

A late developing somewhat offshore low is a good way for your area to get snow, as long as the airmass is decently cold.

It's not out of nowhere, but when I looked at the surface depiction after h5 I expected any surface development to be too far offshore.

12z GFS somehow manages to get a little something going along the coast despite multiple pieces of vorticity intertwining within a positively tilted trough while an amplified ridge is bearing down right on top.

Temps do cool some in our source region towards mid month as the Pacific firehose pulls back and the trough finally retrogrades over the Aleutians. If that look is real and holds, we should have more cold available going forward.

Light rain here now and a bit foggy still. Fog was worse earlier. A balmy 49.

Still a signal on the mean though.

Looking even further out, there are hints for something around the 15th, with a more favorable longwave pattern established and somewhat colder air available.

Other than the Friday-Sat deal that looks dead for now, it appears the period around the 12th is realistically the next trackable threat. Using the EPS depiction here, but the signal has generally been there across ens guidance. As the trough out west lifts, a shortwave is ejected eastward with a ridge beginning to develop along the west coast. The wave is approaching the 4 corners in this panel and tracks eastward towards the Gulf coast states. Low pressure develops in the mid south then tracks towards the east coast. At h5 +height anomalies develop near Hudson Bay as low pressure is organizing over the southeast. Not ideal, but this general setup used to work well for a moderate winter storm in the MA. Temps are an issue verbatim- still not much cold available during this period as depicted.

Just for fun the latest CFS extended run at h5 for the period beyond mid month. Not hating it- looks more Nino than Nina, which continues the general idea we have seen thus far.

GEFS has a little something at least. Temps marginal verbatim but places up near the PA line towards Ralph world might see something modest based on the mean.

The GFS gave it a go.

I'm drinking a Founders Backwoods Bastard, a bourbon barrel aged scotch ale, for New Years eve eve HH. Let's see what HH GFS do.

Looks a lot more like the Euro.

Yeah I mentioned the Hudson Bay "block" when this first showed up on guidance I guess almost a week ago now when Weather Will was liking that period due to the snow maps. The GFS/GEFS may be wrong, but it has been steady with the depiction of how this evolves and the features involved, although it has moved it up in time a bit- it was initially more of a Jan 8th deal. It would be an interesting case to test.

It is, but the GFS/GEFS has been doing this for many runs. The timing and position of that vortex needs to be perfect.

To be clear, relative warmth a day or 2 ahead of a storm isn't the same as having a storm underway and waiting for cold to arrive before the precip shuts off. We see that a lot and it is a high probability fail. Plenty of places are typically mild leading up to a snowstorm. Look at Denver. The storm early last January was all snow, so the cold was in place first. The issue with the possible storm for the 6-7th(other than it only exists on the GFS) is the cold coming in behind the mild mid-week storm doesn't look very cold on guidance, so then we have one of our other classic fail modes- energetic low will generate its own cold air!

It does happen. Last Jan was an example, but the main difference is the cold coming in was legit and sharp. Even though temps were 60 leading in, it started off as snow and much of it fell with temps in the low to mid 20s. The way this pattern seems to be evolving on the means, it looks like more of a gradual transition to somewhat colder. That doesn't mean we can't get a similar result.

I did a hike at Tucakhoe late yesterday afternoon, temp was about 50. Walked through an area that is constantly in the shade, and there was still a patch with a little snow on the ground from the flizzard last Friday. Would have been long gone without the frozen ground.

Need the Canadians and Europeans to get onboard. GFS vs the world hasn't worked out lately. They both have a wave but with somewhat different evolutions, and the ridge behind is more amped/breaks over. In a fast flow it just gets swept off the coast with no chance for surface development.

Looking at the individual members on the 6z GEFS, there is quite a mixture. Most are rain or not much of anything, but some imply a second wave or rain ending as snow. There are timing differences too with a few having precip on the 8th. Overall there are a few more members than previous runs that imply frozen for a chunk of the MA in the 6-8th window.

Stronger signal on the 6z GEFS for a winter storm on the 6-7th, but mostly for PA northeastward into central/northern NE.

Speaking of the 12th, 6z GFS goes boom. A bit discombobulated and late developing the coastal low for our area but close to something big lol.

The GFS is pretty persistent with the wave on the 7th producing frozen somewhere in the MA. Not seeing that on other guidance, and the GEFS has not been very supportive of the idea to this point. The stronger signal across the ensembles is for around 11-12th, and at that point if the pattern progresses (favorably), we should have more cold available.

It was zero on the 12z run. So an improvement lol. Not overly enthused about this window esp for the coastal plain. A few days later, maybe.