Just as the calendar announces the arrival of Spring, our biggest winter storm threat all season is on the horizon. While it is still 3-4 days out, confidence is increasing that a storm will form in the Gulf of Mexico Saturday and move NE until it reaches somewhere near Cape Cod by Monday morning. This track is nearly perfect for heavy snow across the area with the storm being close enough to deliver a lot of moisture and far enough away so any warm air remains well to our SE.
It is important to note, however, that the storm is still a good 3-4 days away. While track changes are certainly possible, it is becoming more and more likely that we do see a high impact storm beginning Sunday afternoon and lasting through Monday afternoon. Here is the 12Z GEM showing the setup Saturday morning as high pressure builds in and low pressure begins to develop. We will have plenty of cold air to go around as Arctic high pressure builds south. At the onset of the storm, temps will be in the 20’s with dew points in the single digits. That will allow for this to be a mainly snow event. Should the low track a little farther west, some mixing could be an issue so we’ll have to keep an eye out for that in the coming days but as of now, this looks like an all or mostly snow event.
Confidence in track is reasonably good. Most guidance is indicating low pressure develops in the Gulf of Mexico and moves NE to a point right near Cape Cod. However, intensity and timing are the two variables that remain uncertain. The faster the storm is, the less it can intensify and the less snow it gets even if it takes an optimal track. The slower the storm is, the longer it has to intensify and the more snow we get, assuming the same track. This is why despite moderate-high confidence in track, it remains too early to issue accumulation maps. Uncertainty is still high as to exactly how much snow will fall. However, it is looking more and more likely that this is a 6″+ event. Should a slower/stronger solution play out, upwards of a foot of snow is possible. Should a slower/weaker solution play out, amounts would likely be closer to 6″. Currently, I am leaning much more towards the slower/stronger solution though this far out it is important to keep options open.
I’ll have more on the storm tomorrow evening.