We’ve begun our final approach to the first winter storm of the 25-26 winter season. As always, this storm appears poised to have a few tricks up its sleeve.
Summary:
- Snow Begins: Tue 6am – 9am; Ends 3pm-7pm Tue
- Rain/Snow line likely runs through the Hudson Valley
- Snow covered roads likely in many areas
- Snow Accumulation varies with location
- Catskills: 4″ to 8″
- Hudson Valley near & north of I-84: 3″ to 6″
- SE Orange & Putnam counties: 1 to 3″
- Rockland & Westchester: Coating to 1″
Low pressure will develop in the southeast and move NE Monday night into Tuesday. The storm will track along the stalled arctic boundary, and spread precipitation into the Hudson Valley by Tuesday morning. The most difficult part of this forecast is determining the precise track of the low pressure. The exact track will determine where that rain/snow line sets up, and thus the exact impacts different parts of the valley will experience. Guidance has consistently placed the rain/snow line through the Hudson Valley… within 20 miles of I-84. The expectation is that everyone starts out as snow, but a quick transition to rain is expected in Rockland & Westchester counties Tuesday morning. The difficult part is pinpointing what happens north of there.
At this time, our best guess is that the rain/snow line establishes somewhere near the boundary of Putnam & Dutchess counties, extending SW to the border of Orange County and NJ. The best chance for a mostly snow event will be north of I-84. Snow could fall heavily during the late morning and early afternoon hours… possibly up to 1″ per hour for a period of time. Air temperatures at the start of the event will be in the upper 20s, making roadways likely snow covered and treacherous. Make sure you plan for very slick and icy travel conditions Tuesday mid to late morning, and especially during the afternoon.
This will be a fast moving storm, so where it’s all snow… like the Mid and Upper Hudson Valley… a widespread 3 to 6 inches are likely. The Catskills could see slightly higher totals due to elevation, with 4 to 8 inches expected. Rockland and Westchester counties are expected to quickly change to rain… so a coating to an inch is all that is expected. The battleground with this forecast is the area near and south of I-84 (SE Dutchess, Putnam & Eastern half of Orange counties). Enough mild air is expected to creep into the mid levels of the atmosphere in the lower Hudson Valley to change the snow to rain by mid day. This “cutoff” will be impossible to pinpoint in advance, so viewers in those areas should be prepared for surprises. If you’re on the cold side of that boundary, you could get 6″ of snow, but if you’re 5 or 10 miles south, on the warm side… you may get less than 1″. A minor shift of the storm track by 10 to 20 miles could have significant impacts on final accumulations for those areas.
We’ll continue to track this storm, and bring you updates along the way.