weatherwiz

Initial thoughts: Greatest uncertainty is the farther northeast into the state you go. The greatest warm air advection is going to occur well to our southwest, from PA into NJ and likely clipping southwest Fairfield County. Where this occurs is critical because this is where the heaviest banding of snow will occur along with the heaviest rates and highest ratios. I think there is room for some higher totals in southwest CT (possibly in the 6-8" range) but there are questions about drier air advecting in aloft and drying out the DGZ. This could result in a solid 2-3 hour window of moderate-to-heavy snow with snow quickly decreasing in intensity and snow growth become poor. This would also occur as the WAA diminishes. It is also very possible the mesos are throwing us caution flags which need to be considered as many of the mesos essentially have one heavy band, with little outside of this band. That would fit the mold of this setup well as much of the forcing is tied into the strong WAA. Might have time to update this tomorrow. Depends on what I have going on for Christmas after work.

I should add the drier air would probably just hold back accumulation potential. So say if it looked good for 5-6-7"...it may hold it down to more in the 3-5" range. This is BDR. Good solid ~3 hour window for moderate snow then the DGZ goes to crap as drier air works in. I just think this needs to be considered when forecasting the ceiling on this.

well I think its still an encouraging sign for places basically along a line say from Danbury to Bridgeport to Southbury-Oxford-Seymour. But the challenge with this is this will be a nowcast situation because ultimately its how the storm evolves which will dictate where the heaviest banding occurs. I am not as nervous about the dry air anymore...the dry air will work in behind the slug of precipitation and will probably help to enhance rates within the precipitation shield. What I would be most nervous about is where the strongest push of WAA occurrs. Given how far SW models have that it may be difficult to even get more than 2-3" back outside of southwestern Fairfield County. We're going to have to rely on mesos for this one I think and just hope the models can pick up on it

Encouraging to see, but meanwhile Waterbury was not so great...probably 1-2". But this just goes to show that there will be an extreme cutoff with this. A quick look of the euro looks solid for SW CT too. It's basically going to be what the northeast extent of accumulating snow is

12z GFS bufkit looks good for anywhere from 2-4/3-5" for BDR. Decent front end thump before dry air works in aloft.

I wonder if the airmass can be traced back towards Siberia.

Agreed. I haven't dug into ratios yet. I was thinking ratios should be great given how cold we are, but that warming aloft from just above 850 to like 725 might play some sort of factor. But what could help even into central CT is higher ratios to yield potential for an inch. I love these type of storms because there is so much going on in the mesoscale and storm processes that play such a large role. I really wish though the strongest WAA was farther northwest and I also hate how (again) the WAA weakens with time. This is going to net some negative busts somewhere, just a question as to where.

Yeah GFS has not budged much at all which is a great sign and probably is leading the way with this. Going to wait on the Euro then probably put a forecast together. I wouldn't even be surprised to see some thundersnow to our southwest. The ceiling for totals is going to be interesting...going to have to factor in speed and also consider that dry punch. But thinking about it more, I think that dry punch works to enhance snowfall rates and yield potential for thundersnow.

GFS still looks good for SW CT. A solid 2-3 hours of heavy snow probably...actually even a subtle inv trough signature for N NJ, SE NY, and SW CT

You're definitely still in the game but may be right on the edge. You probably go towards Naugatuck/Waterbury and chances drop quite a bit.

Going to be a wild gradient that is for sure. Started getting excited seeing all these QPF maps posted and QPF trends only to get reeled back in looking deeper. I think I would feel cautiously optimistic though if I were in Greenwich or Stamford, New Canaan, Darien...maybe even Norwalk. And I say cautiously optimistic because they should at least get accumulating snow...just a question of whether that's 2-3" or something closer to 5-6" lol.

Actually that probably would be the case and that is exactly what Ryan indicated yesterday.

Yup...I am still hedging southwest CT will get accumulating snow, how much, don't want to jump that gun yet but northwest of Fairfield County into the state...I think its going to be very difficult. I am not putting a lot of emphasis on the NAM into this event right now (until it becomes time to really narrow down where the nest banding will be) but guidance is in good agreement of where the strongest WAA will occur and this is where the heaviest snow and totals will occur.

That's good. I'm not sure what to think of that...I am thinking that the dry air would probably be on the backside of the precip which could could help with some heavier rates. Would see a scenario of where it rips like 1-2" for a few hours then shuts off. Lots of details to iron out today

I wanted too but I guess they're only available on pivotal-plus now and I don't know where else they are available but I would really be curious to see what they look like. When I started looking at soundings I had to double check the time stamps were correct and whether maybe they loaded in error...that's how bad they look lol

I thought maybe it was a cod thing and still some errors with sounding generation but even down into NJ/E PA...those soundings are horrific looking. Thats some serious dry air punching in aloft. I was really shocked seeing the DGZ so high too but makes since because there is a deep warming layer from 850-750. But looking deeper I see why the Winter Storm Watches are where they are. The swath of heaviest snow is going to be tied right into the axis of strongest WAA which is going to be quite a bit away to our southwest. We still should get some light snow into SW CT I think...I was thinking there could be potential for several inches of snow there but may have to rethink to maybe only a couple inches possible.

I like what Ryan said yesterday in that we would probably see a more consolidated band of heaver snow than what is shown. Aloft this kind of looks like crap. Have to fire up bufkit but some of the forecast soundings on the northern side of that precip shield look like crap...even within Fairfield County which I was thinking could have some potential for several inches. But still too much uncertainty to really have any concrete thoughts and that blocking we can't discount. Hopefully we'll get a bit more clarity with the 12z suite.

yup...getting worried its going to turn into what happened last year. Bruins were right in the thick of things right up until about this time of year. Oh well...if they are going to keep losing thankfully they are close enough to the bottom to where they could have a shot for the #1 pick if the lottery balls fall their way.

Ottawa has made them look foolish twice this year

White Christmas and bruins both delivering tonight

Took the dog outside after the first period and it’s like raining snow lol. It sounds like rain but it’s snowing…or more along the lines of sleet/graupel hit ground is coated.

Someone in PA is going to get some significant icing. I don't see much room for this to get any farther north but SW CT may still be in the game for accumulating snow.

Well after today I still need 94.5" to hit 100

its been great seeing positive trends moving closer to the window of interest versus negative trends. Something is going to work in our favor over the next 10-14 days.

Friday is a real day, yes