For The Rest Of Today: A sunny to partly sunny rest of the day is expected across Western & Central Mass. High temperatures this afternoon will be between 44 and 48 Degrees.
Tonight: Clear to partly cloudy skies are expected tonight with low temperatures near 25 Degrees.
Sunday: High pressure will remain in control of our weather for much of the day Sunday. Skies will be sunny to partly sunny during the morning with an increase in clouds expected during Sunday afternoon. High temperatures Sunday will be near 40 Degrees.
A Prolonged Ice Storm Is Expected From Late Sunday Night Through New Year’s Eve: A prolonged freezing rain and sleet storm seems to be setting up for parts of Western and Central Mass into northern Connecticut beginning around midnight Sunday night and continuing through Monday, Monday night and into New Year’s Eve. This is still expected to be a two part storm.
Part 1 of this storm is expected from about midnight Sunday Night through the day on Monday: Precipitation is expected to overspread Western and Central Mass and northern Connecticut by about midnight Sunday night. A northeasterly wind flow thanks to an area of high pressure over Maine and New Hampshire will help to draw sub-freezing air into the region by later Sunday night. This sub-freezing air may remain locked in across Western and Central Mass through much of Monday.
This all means that we may start out as a very cold rain across much of Western and Central Mass around midnight Sunday night, but the rain will change to freezing rain and sleet from north to south late Sunday night. At this time, it looks like areas north of the Mass Pike will see a prolonged period of freezing rain mixed with sleet late Sunday night through Monday with temperatures remaining between 30 and 32 Degrees. Meanwhile, areas along and especially south of the Mass Pike may see alternating periods of freezing rain and rain late Sunday night and Monday as temperatures will hover between 32 and 35 Degrees.
One thing that we will need to closely watch is for a period of heavy precipitation that occurs throughout Monday morning into early Monday afternoon. This heavy precipitation will not only enhance the freezing rain and sleet accumulations north of the Mass Pike, but it could also cool the atmosphere down enough so that freezing rain may occur across all of Western and Central Mass, as well as across all of northern Connecticut.
With all of that said, there continues to be A LOT of uncertainty as to how far south the colder air will drain into southern New England and how deep will this cold air be. At this point, I still that accumulating freezing rain and sleet will occur across areas north of the Mass Pike. With that said, it will take very little additional cooling of the atmosphere for the changeover line from rain to freezing rain and sleet to push as far south as Springfield and Hartford & this is something that will need to be watched closely.
Part 2 of this storm is expected from Monday night through the day on New Year’s Eve: The second part of this storm will be caused by a developing second low pressure system that will move from the New Jersey coastline to southeastern Mass by Tuesday morning. The second low pressure system is expected to take a track so that an easterly wind flow will set up Monday night and New Year’s Eve causing the second part of this storm to be mostly a cold rain across a large part of Western and Central Mass. The exception to this will be along and north of Route 2 where a mixture of snow, sleet and freezing rain is expected Monday night into New Year’s Eve.
With that said, I do have concerns that the cold low-level air will have a tough time being scoured out. Should this occur, then we could see the freezing rain continue through Monday night into part of New Year’s Eve. This is something to keep a very close eye on.
Bottom Line Is That significant ice accumulations from freezing rain are quite possible in a zone that stretches from south of Route 2 and north of the Mass Pike. Most of this ice accumulation is expected to occur from just after midnight Sunday night through all day Monday to about early Monday evening.
With that said, there are caveats to this forecast – Very small changes to the atmospheric temperature profile will make for significant differences in what you see in terms of freezing rain and sleet accumulations. I do think that there is enough evidence in the data to suggest that significant ice accumulations will occur in the Worcester Hills and across the Berkshires where colder low-level air will be able to lock itself in the most. With that said, I have serious concerns about the Pioneer Valley/I-91 corridor where weather guidance tends to “warm things up” too quickly and in the end we see much more icing.
The areas that do see significant ice accumulations may see power outages and tree damage. In addition, extremely hazardous travel conditions are expected in areas that see a prolonged period of freezing rain late Sunday night and Monday. In fact, I expect that hazardous travel conditions will occur across most, if not all of Western and Central Mass and northern Connecticut throughout late Sunday night and all day Monday.
Thank you for reading my latest forecast for Western and Central Mass.
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