We continue to track the developing upper level low pressure system that will bring us our first soaking rain in nearly 2 months.
Upper level low pressure pushes into the Great Lakes on Wednesday, and that deepening trough will cause a surface low pressure to develop along the coast, as shown in the graphic above. This should result in the development of a good swath of light to moderate rain to develop. Rain likely develops near or after sunset on Wednesday, and continues through the night… into Thursday morning. Scattered rain showers are possible through the day on Thursday. But by sunset on Thursday, some much welcome rainfall totals are expected.
Widespread totals around 1 inch of rain appear possible at this time. Some localized totals near 2 inches can’t be ruled out either. In some cases this would be 5x as much rain as some areas have seen in the last 30 days.
Mountain Wet Snow Potential??
As the upper level low pressure digs into the Great Lakes, and pushes over NY state, it will cause the air to rapidly rise… which will cool the air, and pull cold air from the mid levels, down to the surface. This will cause rain to transition to wet snow in the Catskills and Poconos during the day on Thursday… and that wet snow could persist into Thursday night. Our current ideas for snow accumulation are as follows…
Higher elevations of Sullivan, Western Ulster, Western Greene… and Delaware counties… are likely to see their first accumulating snow of the season. The higher in elevation you go, the higher the snowfall totals could be. Some of the higher peaks could see snow totals over 6″. So if you live in those traditionally colder parts of the region, you’ll want to watch closely in the coming 2 days.
But these upper level low pressure systems are tricky… very tricky. It’s a dynamic weather phenomenon, and the air can cool rapidly… even in the valley areas. There is a low probability (perhaps 20% to 30% as of Monday night), that the combination of strong upward motion and rapidly cooling air, could lead to a period of wet snow across portions of the Hudson Valley.
Futurecast Radar : 4pm Wednesday – 7am Friday
You’ll notice on this NAM model simulation, that the rain pushes through early on Thursday morning… and then stalls out as the upper level low approaches. The cold air filters to the surface, and the rain begins to mix with wet snow. Then eventually, a band of moderate, wet snow sets up over the Hudson Valley by sunrise on Friday… thanks to the strong atmospheric lift of the upper level low pressure. Is this scenario likely?… probably not. But it needs to be monitored… as some of the computer guidance is very interested in this idea Thursday night into Friday.
A VERY busy week ahead of us, we’ll have updates to share along the way, both here and on the Facebook page.