The final couple Premium updates of the night have been released, and as has been done with this storm due to its severity, the relevant parts of the forecast have been released freely to inform the public of any/all storm hazards. This will also be the final free update of the night. The forecast has been slightly revised down for Fairfield County, but the overall idea on the storm remains the same:
First, the final snowfall forecast is as follows: 10-20 inches remains for Westchester County, 12-24 inches for Fairfield County, and 16-28+ inches for New Haven County. And the craziest part of all of this? The gradient may not be tight enough, even in that forecast. I want to show you something; the latest 0z HD NAM here. While obviously not a perfect representation, that is everything from .4 inches of liquid in western Westchester County to over 2 inches of liquid in eastern New Haven County. So that’s a range of 6 inches to over 2 feet of snow within just the three counties that I forecast. This is EXACTLY why I have been emphasizing from the beginning the huge variability in this forecast and have been cautioning against those calling for 2 feet widespread. Those 2 feet amounts remain quite likely across parts of CT, and may certainly still be possible in New Haven County, especially based on the latest data.
This sharp gradient is similarly supported by short-range RAP weather model guidance. Looking at over an inch of liquid in most of New Haven County, equating to around 14-20 inches of snow (note the storm is still not done when these graphics are presented). In Fairfield County, verbatim shows around three quarters of an inch to an inch, or around 10-14 inches or so. Still the lower-end of the overall range, but take a look at the latest radar right here. Definitely fairly impressive. You can see why the New Haven forecast is higher confidence, as they are already in that heavier precipitation and there is strong lift actually enhancing banding as it moves into the eastern part of that County. Going over to Fairfield you see the banding entering Bridgeport now and transferring west. These bands will give you the first real blizzard feel across the region. So New Haven is in the midst of the blizzard with it about to get worse, and it will be in Fairfield County shortly. To me, Westchester County remains that real wildcard, as someone could see as little as 4-8 inches. I’m not giving up on it yet, especially as the National Weather Service remains optimistic in their forecasting outlooks and the radar remains impressive as it enters into Fairfield County, but as I have expressed for awhile, they will see the lowest accumulations, while Fairfield County and into New Haven County will be seeing the highest totals.
What this all makes (because why would it be any other way?) is an extremely difficult forecast right across the SWCT/NY region. Observations indicate the previous forecast was on track, but almost all modeling guidance shows that the heaviest precipitation won’t make it quite as far to the west. Thus, I went with an average of the two for the areas likely to be impacted, but weighted observations more heavily. I certainly did not lower snowfall amounts as much as models dictated I should as I see plenty of support for heavy snow moving through. But with observations not entirely contradicting the models, it is hard to go entirely against our computer guidance, especially this close into the storm when going against the guidance more often results in a bust than not. Thus the minor reduction in Fairfield County, but no real other changes. Snow begins to wind down outside of bands between 11 PM and 1 AM tomorrow, but in bands could take until 4 PM to really wind down.
Winds continue to pick up across the area on track as well. However, at this time, I am not really seeing any reports of power outages at all. The town of North Stonington has some as of 11 PM (8% of the town), but that’s really it at this point. I do expect some isolated outages to pop up as the winds continue to pick up, but it is a good sign that we do not have many reports through 11 PM on the CL&P website. I’ll continue checking through the night and keep you updated on that. If outages are to occur, they are most likely to occur between 1 and 5 AM I still believe, and confidence in this forecast is high seeing as the 10 PM start time for the noticeable gusty winds was right on target.
In summary, heavy snow is moving through New Haven and Fairfield Counties on time right now, with one of the main bands about to enter Westchester County. If I were to express my concerns, my first would be western Westchester County reaching the 10 inch minimum for that county. Just not sure how sharp this cutoff will be, and I think it will probably be a close call. Even northern Fairfield County could be in a little bit of trouble due to the shape of this storm, but lots of heavy precipitation to move in there as well. Snow will continue to pick up through the night, as will the winds, but the winds begin to die down into the morning and through the day tomorrow. Heaviest winds may accompany heaviest snow, and isolated power outages still remain possible for the region.
Thank you for bearing with me through what has been an extremely tricky storm, and I have been happy to release so much content freely to keep you informed about all of the subtle changes with the overall forecast. Free updates will continue tomorrow morning, with the first one progged to come around 10 AM, and updates will continue on Twitter, so please be sure to stay tuned for the latest! Similarly, a light snow threat Thursday night into Friday will be followed by another snow threat early next week Sunday night into Monday, so definitely a lot to keep covering! While potentially sleep-deprived, I’ll do my best to get the best forecasts out both to Premium clients and freely here as well. So thank you again, and be sure to keep it here!