Rain Changes To Freezing Rain & Sleet By Late This Afternoon & Early This Evening; Freezing Rain, Sleet & Some Snow Expected Tonight & Friday Morning Across Western & Central Mass

An area of low pressure is expected to track just to the south of Long Island during tonight. The track of this low pressure is such that it’ll be able to pull down cold enough air to produce a very messy mixture of freezing rain, sleet and even some snow across the entire area starting as soon as late this afternoon and continuing through tonight and Friday morning.

Rain is expected to continue through mid-afternoon as temperatures mostly remain just above freezing across the region.

Things become a lot more complex in terms of when the precipitation will change to freezing rain and then sleet from north to south across the region & also how much sleet and ice accumulates. Trying to figure out the temperatures in the mid-levels of the atmosphere are going to be crucial in determining whether this is going to be an all-out ice storm across parts of the area or if this is going to be a sleet storm across much of the area tonight. Only a 1 to 2 degree Celsius change in the temperature is going to mean the difference between almost all sleet or almost all freezing rain. Not an easy forecast!!

I do think that areas north of the Mass Pike will change from rain to freezing rain by about 5-7 pm today. Areas near and south of the Mass Pike look to change from rain to freezing rain by about 7-9 pm or so this evening. The exception to this looks to be the lower Pioneer Valley of Western Mass where rain may just change to sleet this evening between about 8 and 10 pm or so.

During tonight, I think that areas north of the Mass Pike will gradually change from freezing rain to a sleet storm between about 10 pm and midnight. Sleet then continues across areas north of the Mass Pike during the after midnight hours of tonight. It should be noted that the northern Worcester Hills may change from sleet to snow at some point during the after midnight hours.

For areas near and south of the Mass Pike, the predominant precipitation type may end up being freezing rain throughout tonight. This is something that’ll need to be watched very closely as ice amounts of over one quarter (0.25”) of an inch to perhaps up to one third (0.33”) of an inch could lead to ice buildup on trees and power lines leading to scattered power outages.

One big wildcard to tonight’s forecast is going to be whether there is a burst of snow during the after midnight hours of tonight or not. Should this occur, then there could be a quick few inches of wet snow that accumulates across northern Worcester County. In fact, some of the high-resolution model guidance show quite a heavy burst of snow pushing as far south as Worcester, the I-290 corridor & the Route 9 corridor during the after midnight hours of tonight. I’m not buying into that high-resolution guidance yet, but it’s something to certainly watch.

Turning to Friday morning, snow across the northern Worcester Hills, sleet across areas north of the Mass Pike and freezing rain across areas near and south of the Mass Pike will come to an end by mid-morning.

It goes without saying that roads are going to be one big mess tonight across the entire area. Freezing rain and then sleet across areas north of the Mass Pike will lead to some slick conditions during all of tonight. Freezing rain near and south of the Mass Pike will produce some icy conditions on roads and all other surfaces. It’s likely to be slick out there tonight!!

Additionally, the Friday morning commute is likely to be a mess as well due to snow across the northern Worcester Hills, sleet across areas north of the Mass Pike and freezing rain near and south of the Mass Pike.