The next storm up in this active streak will be a messy one on Thursday. This frontal system's primary low will pass to New England's north while a secondary, surface low passes near southern New England. This will yield a wintry mix of precipitation across New England with all precipitation types on the table at some point.
This storm will begin as a burst of snow for everyone in New England. A changeover to a mix and eventually plain rain is expected to occur from south to north through Thursday afternoon and evening. The plain rain may be limited to southernmost New England for a majority of the storm as temperatures will likely really struggle to rise above freezing for most north of the northern Connecticut and Rhode Island borders.
Across much of northern New England, thermal profiles will warm during the day, but likely stay cold enough to support mainly snow through the storm. With that said, a change to freezing rain or drizzle will be possible as the storm is pulling away. The mixing line is most likely to reach southern New Hampshire and southern Vermont by mid-afternoon.
Snow will likely begin to break out around, or just after, sunrise for southwestern New England. Snow will steadily advance northeast throughout the morning, likely covering all of New England outside of eastern Maine by midday. Around midday is when the first hints of a changeover will likely occur across the south coast. This initial burst of snow may be the heaviest of the day and will be capable of moderate snowfall rates. Snow will begin to accumulate quickly given the cold conditions preceding the storm.
Below: HRRR showing potential weather just after sunrise (1st image) and around late-morning (2nd image):
Through the afternoon, as warmer air works into the region aloft, a gradual changeover to freezing rain and sleet is likely to occur from south and west to north and east. Snow will continue to push across Maine through the afternoon. This is a quick-hitter, with precipitation beginning to wrap up in the early evening and steadily shutting down from southwest to northeast as the evening and early part of the night progresses.
Below: HRRR showing potential weather around mid-afternoon (1st image) and in the evening (2nd image):
The biggest issue with this storm has been (and will continue to be) how the thermal profiles play out. The primary low pressure system will advect a warmer air mass into the region aloft. A weaker, secondary low pressure system passing near southern New England will help keep cold air trapped at the surface. The secondary low will likely not become strong enough to become the primary low, which is why some warmer air can still get into the region aloft. This is a perfect setup for mixed precipitation across New England.
The question becomes exactly how thermal profiles respond to this setup. These profiles look supportive of all snow everywhere through the morning hours. Surface temperatures will likely become very cold tonight before clouds move into the region. The warmer air aloft will likely begin to advect into the region in earnest in the afternoon, allowing a changeover. The question is how quickly that can occur. Modeling often erodes cold air much too quickly, but it should erode for a transition to occur across southern and central New England.
Below: Temperatures around 4,700 feet above sea level late afternoon Thursday. The area that transitions from blue to more of a green color is near the freezing mark. The 2nd image shows projected surface temperatures at the same time. You can see how much farther south the sub-freezing air is at the surface versus aloft:
Overall, trends over the past 24 hours have been for a bit more moisture associated with the system as thermal profiles warm. This will allow for more precipitation and higher precipitation rates. With that in mind, we've expanded our 3-5 inch zone a decent amount since yesterday evening's update. It still looks like most of New England will end up with 2-5 inches of snow with the lower end across southern New England (due to mixing) and the northern tier (due to lighter snowfall rates).
Another issue with this storm will be what precipitation takes over once the changeover occurs. Both freezing rain and sleet will be on the table once mixing begins. With that said, it has been looking like the cold air layer at the surface will be on the shallower end, which would support more freezing rain/drizzle with a shorter period of sleet, or some sleet mixing in.
The good news is that the precipitation will be snow when precipitation rates are heavier. With that said, only light ice accumulations are expected, with minimal to no impacts to trees or infrastructure. A glaze of ice will be possible, which will certainly add to the slippery surfaces that will already be covered by frozen precipitation. As of now, the chances for over a tenth of an inch of ice remain capped at just 5%.
Below: Probability of at least a glaze of ice Thursday:
After this storm, the next one will be coming Saturday night into Sunday. The overall setup will be similar to Thursday with a system ejecting out of the Great Lakes and a secondary low forming south of New England. There are some key differences, though. These differences include a track generally further south than Thursday, a stronger secondary low and more moisture to work with.
All of these differences point toward a generally more impactful storm in regards to snowfall. The area that stands the best chance at the most snow will be just north of where a mix/snow line sets up. There is a decent chance at several inches of snow, possibly 6+ in the jackpot zone. With that said, trying to place the jackpot zone or put specific numbers on this storm is currently a fool's errand. As of now, the area to watch will be near the northern Massachusetts border.
Below: Likelihood of impactful winter weather later Saturday to Sunday morning:
Another storm looks to be on tap around the middle of next week as well. Normally we wouldn’t bother bringing this up a week out with plenty of uncertainty, especially with two storms already in front of us, but the large-scale pattern producing this active stretch is unlikely to break down by then and the timing certainly fits, so we’ll be watching it. This one could be pushed even further south.
Below: Current likelihood of impactful winter weather around the middle of next week (February 11-13). This will be shifting around in the coming days:
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