Pattern Turns Unsettled and Generally Cooler for New England
- Tim Dennis
- Mar 21
- 4 min read
By early this afternoon, the cold front crossing New England and its attending low pressure system will have cleared most of New England. A drier air mass will quickly move into New England this afternoon, shutting off widespread precipitation from west to east. Maine will, naturally, remain within the widespread rain and snow showers the longest, with precipitation winding down through the afternoon and evening.
Below: HRRR showing expected weather early this afternoon:
The area of low pressure along the front has been intensifying rather efficiently, which has allowed for rain to effectively make the transition to snow across the higher elevations of northern New England this morning. For the lower elevations, the drier air working in behind the system will win the race over the falling temperatures and clear the showers out before any kind of changeover can occur. All of eastern Maine could see rain end as snow late this evening as the system continues to slow down.
HRRR showing potential weather this evening:
As the drier air mass works into the region, clearing will begin. Winds will shift to a northwest flow as well. This will allow for better mixing and stronger wind gusts this afternoon. Gusts of up to 40mph will be possible across the region with the potential for stronger gusts in the Berkshires and southern Green Mountains. This is generally below impactful levels, but with cold air advection ongoing, it will certainly be a chilly wind.
Spring is the time of the flip-flopping temperature, and that's exactly how this spring will be kicking off. Today's cold front will bring a cool and raw afternoon. On Saturday, flow will briefly return southerly ahead of an approaching cold front, allowing for a quick rebound from today and tonight. That front will cross New England later Saturday into Sunday, bringing a quick cool-down for Sunday on renewed cold air advection.
That cold front on Saturday will likely spark a line of scattered rain and elevation snow showers Saturday afternoon and evening. A sharp cool-down is likely behind the front, with a flash freeze possible for the northern third of New England Saturday afternoon and night as the freezing altitude plummets. With that said, there won't be much precipitation and increasing winds behind the front may dry things out before a freeze occurs. Sunday will likely end up being very similar to this afternoon behind this latest frontal passage.
Below: HRRR showing potential weather Saturday evening:
The next, more widespread storm system will enter New England Sunday night into Monday of next week. This system will involve a trough from the Great Lakes moving to the north of New England. A surface low may develop along the storm's triple point (where a cold, warm and occluded front meet) and rotate into New England. This system continues to look like it will bring a shot of snow for many in New England at the onset Sunday night and/or Monday morning before changing to rain from south to north as a warm front lifts north during the day Monday.
An area of high pressure over Quebec will try to lock colder air into northern New England during the day Monday, potentially delaying a changeover to rain. With that said, an offshore high pressure will try to promote a southerly flow as a warm front lifts into New England. The placement of this warm front will be dictated by the track of the triple-point low.
These features could lead to a situation where the rain/snow line stalls somewhere over northern New England, with the storm remaining mainly snow on Monday to the north of this line. Where the rain/snow line sets up Monday and how quickly (or slowly) it advances northward will be the primary question that needs to be answered with this system in the coming days.
This will have the potential to bring an accumulating spring snowfall to northern New England and possibly interior southern New England. Given the current trends, snowfall amounts will increase the farther north you go in New England (and, of course, the higher up within the terrain you go). This currently doesn't have the make-up of a large or powerful storm system, so substantial snow accumulations remain unlikely anywhere in New England. The Winter Storm Severity Index currently shows low probabilities for moderate impacts and moderate probabilities for minor impacts for northern New England.
Below: Current probability of impactful winter weather Sunday night to Monday:
New England will generally remain in a trough for next week, keeping the weather unsettled and cooler. After spending much of the first half of the month with a ridge over the east and troughing over the west, the script will be flipping to close out March. Yes, the sustained mild conditions over the past couple weeks was indeed New England's "fool's spring" as cooler conditions are expected to close out March and begin April.
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