Good evening!

An area of low pressure moving north just off the mid-Atlantic coast is strengthening rapidly this evening, setting the stage for a long-duration heavy rain and strong wind event. Let’s break it down.

Tonight, rain will spread from southwest to northeast as that low undergoes ‘bombogenesis’, which essentially means it intensifies very quickly. For a storm to be considered a bomb cyclone, the pressure must drop at least 24mb in 24 hours. We’re on track for that to happen, and by daybreak Thursday, that storm is pounding us with intense rainfall and potentially damaging wind gusts.

By midnight, we have widespread rain, heavy at times, that persists through the Thursday morning commute. Ponding on the roadways should be anticipated as a precursor to possibly hydroplaning. Don’t forget, in late Fall, wet leaves make for a slippery surface, too.

Rain will linger on and on throughout northern New York and into southern Vermont, with some shadowing from the White Mountains contributing to a tapering off through northern Vermont (especially the Northeast Kingdom) and northern and central New Hampshire in the afternoon. By daybreak Friday, all rain slowly winds down, but totals will have reached 1-3″.

That rainfall is more than enough to lead to small stream flooding and very swollen, fast larger rivers. Urban street flooding is possible, too, as storm drains likely become clogged by typical Fall leaf debris.

Throughout this stretch, the temp hovers in the 40s, first dropping there tonight and then not budging Thursday. At and above 2500′, temps will be in the 30s and some snow could mix in with that rain. Minor accumulations are possible for the Adirondack High Peaks, along the spine of the Green Mountains and White Mountain summits. This is a mostly rain event, however. Sorry, snow lovers!

The wind is the other major variable with this thing. Top wind gusts, particularly along the western slope of the Green Mountains and in the Champlain Valley, could hit 40-50 mph. The wind, out of the south for much of Wednesday, will shift to out of the east tonight then north during the day on Thursday. Wave heights of 5-7′ on the open water of Lake Champlain will make for a rough and possibly delayed ferry crossing. That wind will also be responsible for a few isolated to scattered power outages as small tree limbs are taken down. Those who drive high-profile vehicles, such as box trucks or vans, may find it difficult to get around Thursday morning.

Friday, slowly all of this comes to an end. Showers taper off during the morning with breaks in stubborn clouds coming to us by the end of the day and into early Saturday. A northwest wind of 10-20 mph Friday, dies off to a mere 5 mph into the weekend. It’s low to mid 50s Friday, then mid to upper 50s Saturday and finally low 60s Sunday for a nice warming trend. Look for sunshine both days! The threat for heavy rain returns late Monday into Tuesday.

Have a great Thursday! Drive safely!

-Skytracker Chief Meteorologist Amanda Thibault