A Messy Storm Will Bring Snow To Start With Tonight That Changes To Freezing Rain, Sleet & Some Rain During Thursday Morning: An area of low pressure is expected to track across northern New York State and northern New England late tonight and Thursday morning. At the same time this is happening, some sort of a secondary low pressure system is going to try to form near Long Island tonight and track across Southern New England during Thursday morning. Both storm systems are expected to bring an initial period of snow starting this evening that changes to freezing rain and sleet by sunrise Thursday morning. This freezing rain and sleet might change to rain in some areas (more on that later in this update) during Thursday morning, but that all depends on how much cold air remains locked in near the surface due to the combination of a high pressure system over Atlantic Canada and that secondary low pressure system tracking right over our area.
As I already mentioned, light snow is expected to gradually begin across the entire area this evening, so that by midnight it should be snowing everywhere across Western and Central Mass. This snow is expected to continue during the after midnight hours of tonight before it begins to change to freezing rain and sleet from south to north by just before sunrise Thursday morning. Snow amounts tonight are expected to average around one inch or so for most areas. The exception looks to be across the northern Worcester Hills and across the Berkshires where 1 to 2 inches of snow accumulation looks likely.
Hazardous Travel Conditions are likely during Thursday morning’s commute due to freezing rain and sleet.
The change from snow to freezing rain and sleet looks to first occur across areas near and south of the Mass Pike by about 5 am Thursday morning. The changeover line from snow to freezing rain and sleet is then expected to push quickly north so that by 7 am, there is likely to be freezing rain and sleet occurring everywhere across Western and Central Mass.
The question then becomes whether the freezing rain and sleet changes to all rain at some point during Thursday morning or not. With a favorable look in terms of cold air damming, which is when below freezing air at the surface gets locked in across the Worcester Hills and across parts of the Pioneer Valley, the changeover from freezing rain to just rain may not occur at all across the Worcester Hills in the area west of I-190 and also across the Hilltowns of Western Mass. This is something that’s going to have to be watched extremely closely because if the precipitation does not change to rain and remains as freezing rain, it would mean that ice amounts of up to one quarter of an inch could occur leading to some extremely hazardous travel throughout all of Thursday morning, as well as the possibility of some isolated power outages due to some tree limbs snapping from the weight of the ice.
For now, it appears that the freezing rain will probably change to rain across areas near and south of the Mass Pike, across the lower Pioneer Valley and across eastern Worcester County by about 9 am Thursday morning. For areas north of the Mass Pike, the change from freezing rain to rain may occur as far north as the Worcester Metro and the I-290 corridor by 10 am. Precipitation may stay as all freezing rain across areas north of Worcester, including areas near and west of I-190 and along the Route 2 corridor from Fitchburg and Leominster and points west. Also, precipitation may stay as all freezing rain across the I-91 corridor from about South Hadley and Northampton and points north.
All precipitation is expected to come to an end by between 12 pm and 2 pm Thursday afternoon.
As for ice accumulations Thursday morning, current indications seem to point towards amounts that range from less than one tenth of an inch across areas near and south of the Mass Pike and across eastern Worcester County to one tenth to two tenths of an inch of ice across areas north of the Mass Pike and across the entire I-91 corridor, including both the Springfield and Worcester metro areas. Up to one quarter of an inch of ice is a very real possibility across the Worcester Hills west of I-190 and across the Hilltowns that surround I-91.
I am going to be watching this storm extremely closely and will have updates as needed. One thing that I will be paying particular concern to is how prolonged the freezing rain might be during Thursday morning. Like I said, I have concerns that the cold air might remain locked in tight and keep most areas below freezing throughout Thursday morning leading to much of, if not all of Western and Central Mass to see freezing rain.
Quick Update On The Weekend Storm: Even though I’m keeping close tabs on the storm this weekend, I didn’t dig too much into the data as I already have my hands full with tonight and tomorrow morning’s storm.
That said, it still looks as though this is going to be another messy storm that begins as snow during Saturday afternoon with the snow continuing into Saturday evening. A change from snow to freezing rain then looks to occur by later Saturday night with the freezing rain changing to all rain sometime during the day on Sunday. The rain then comes to an end by Sunday evening.
It should be noted that when exactly the precipitation changes from snow to ice and then to rain is uncertain as any lingering cold air near the surface may prolong the freezing rain on Sunday. These exact details are something that really can’t be sorted out until about a day or two ahead of time. It’s certainly possible that areas north of the Mass Pike, especially the Worcester Hills may hang onto the cold air leading to a prolonged icing event on Sunday and this is something that will need to be watched closely.
Finally – The weather pattern is expected to remain very active possibly right through the end of this month, which means we may have at least a couple of more storms to contend with during next week and the following week. In fact, the longer range weather forecast guidance have been pretty consistent with showing the possibility of a storm that brings mostly snow to the area around next Thursday the 20th & yet another storm that affects the area with more winter weather around the 24th or so of this month.
Comments