bristolri_wx

Those GDPS/GFS maps are getting better... and still have two more cycles to do so... and you can assume 10-1 won't cut it, as every single met has said there will be higher rates, more like 12-1 to 15-1... maybe more... so more interested in QPF maps than snow maps with low ratios at this point...

Let's keep in mind that the 10-1 maps are not gonna be accurate for this thing. Neither is the Kuchera's, but somewhere in the middle is where we end up for ratios.

FYC

All the high-res 12z models are inching westward and upward from their previous runs. Feeling better about that even as we have other models wobble a little back and forth... the 3K NAM looks awesome as well, once you assume ratios in many places will be higher than 10-1.

I think you're being conservative. It won't take much for us to get 12-18" out of this one. No p-type issues on any model for us. Considering someone somewhere is gonna get 24-30" to the NE of us figuring we get half of that isn't outlandish. Even the RI snow holes are over a foot on most of the guidance.

I mean at this point if the Euro stays on point at 12z, then you just start mostly ignoring the other output unless you see really see drastic changes at 500mb and 700mb. @Ginx snewx has stressed this and I believe this too. It's just so UNUSUAL for this type of disagreement this close in, but then again, this is an very anomalous setup, so maybe resolution isn't on your side in this scenario... also, anything that NCEP is running with an FV3 core doesn't seem to be getting a good handle on this. Something for them study after the storm if the Euro/NAM solution holds up.

No more Blizzard Watch. They still have warnings.

There’s a lot of Irish pubs out there that make a great Shepard’s Pie, though home made is often the best.

Nope not saying that at all. The high-res models are just preventing me from being confident. More times than not the high res and the euro are in agreement at this range. It definitely could be an overly complex situation that’s causing divergence. The fact that the Euro has been solid for several runs in a row is a reason to stick with it for sure.

The Euro and the NAM seem to be on their own with the heavy precip and westward extent. Some of the other hi-res models aren’t as bullish for central and western New England. Wish this felt like a slam dunk for everyone but waking up still feel like there’s still some details to sort out today that will affect this board. Only consensus is for 12” or more east of 95/495… that’s about it and we are 18 hours from go… weird…

So no concern with the Hi-Res models being farther east with this thing?

It was posted somewhere in this thread near/during the 18z catastrophe yesterday…

Yeah looking over records now usually just short of 24".

I'm not discounting your theory it may end up being less in the locations you mentioned, but I'm sure that all of the locations you have mentioned have seen two feet of snow on a few occasions in the last 25 years. But yes, very rare, and almost never a jackpot location in this setup.

Yeah looking at that now. Also more noticeable on the surface after HR 54...

GFS doesn't seem that far west or improved on the Pivotal surface maps. I'm not looking at the other levels though... maybe I'm missing something...

Hope we beefed up the American Weather server capacity for tonight. It's gonna be busy in here lol.

It's insanity that 48 hours before a storm that mathematical probability ranges end-to-end getting spit out out are 8-38". Amazing.

The Cape is always "threatened". It's right next to the ocean thats not frozen. That's as much "accumulated snowfall" you'll see over the ocean on any storm. The fact that it shows snow over the ocean means mixing most likely not going to be an issue.

Let's add to the model watching fun and make "blizzard watch" a drinking game!

7:10 BOX DISCUSSION: Details... Friday night through Saturday night... ***A Strong Winter Storm will impact southern New England Saturday*** After a jog east with the 12Z/18Z guidance yesterday, this evening`s 00Z models have ticked back west; a windshield wiper effect we often see in computer models leading up to these events and why you don`t want to hang your hat on one deterministic model run. This remains a decidedly chaotic forecast with decent run-to-run consistency in some models/ensembles, but large model-to-model discrepancies. One of the biggest struggles is how to resolve the upper air pattern with northern and southern stream energy that may phase leading to a more volatile system. The biggest outlier is the GFS which continues to depict a track well southeast of the 40/70 benchmark, while the NAM/Canadian/ECMWF are further northwest (if much slower, in the NAM`s case). For now the forecast continues to go with a blend of guidance, more or less in line with the ECMWF run which is a compromise between the GFS east and UKMET west. Ultimately the evolution of the parent 500 mb trough that digs into the Ohio and Tennessee valleys Friday night and Saturday will help to determine the track of the surface low. Confidence is high that this low will strengthen rapidly as it moves up the east coast, likely undergoing bombogenesis, meaning its central pressure drops at least 24 mb in 24 hours. This will bring the threat for significant snow, potentially damaging winds, and coastal flooding. Thinking this morning is that the significant snowfall threat will be centered over southeast Massachusetts, diminishing to the northwest. Given QPF of nearly 1.5 inches toward eastern MA and a cold column leading to snow-to-liquid ratios greater than 10:1, snowfall totals of 12 to 18 inches are possible; greater beneath any deformation band that sets up somewhere northwest of the low. A Winter Storm Watch has been issued for eastern and central MA as well as eastern CT; this is where we have the highest confidence of significant snowfall. Strong, potentially damaging winds are also a significant hazard with this system given a 60 to 70 kt low level jet overhead thanks to the explosive deepening of the low. Bufkit soundings indicate a well mixed boundary layer, up to 850 mb on the southeast coast Saturday and Saturday night. The strongest winds will be over Cape Cod and the islands. Coastal flooding is the final threat we`re concerned about. This would be during both high tide cycles on Saturday, but moreso in the evening. Though the astronomical tide is higher in the morning, winds and seas won`t fully ramp up until later. Thus, we continue to expect a 1-2 ft surge leading to minor coastal flooding on the east coast Saturday morning. For the evening high tide that surge will be more like 3+ ft. Factoring in the 20-25 ft seas just offshore, widespread minor coastal flooding is likely with pockets of moderate. Again, timing will be crucial for us to realize this upper end of flooding potential, if the max surge can coincide with the high tide.

I totally understand everything you're saying and this stuff isn't easy by any means. It just seems silly to me that US models aren't as good at some types of US weather than other agency's forecast systems. We should strive to do better for our own backyards, especially when its a pretty densely populated area, and their own mission is "provide weather, water and climate data, forecasts, warnings, and impact-based decision support services for the protection of life and property and enhancement of the national economy."

The GFS has two extra runs per day to make it look like it's "hanging tough". If you compare 0z to 12z it looks just as crazy. QPF went from 1.1" to .10" at my location. That's garbage.