Brief Break for New England Before the Next Slug of Precipitation

New England will be under the influence of a ridge of high pressure over the next couple days. This is a rare ridge in a trough-dominated pattern over the past couple weeks. This ridge will bring back the sunshine temporarily, but will also aid in keeping temperatures on the colder side, especially overnight tonight. With yesterday's storm system moving well north of New England and the high pressure to the west, it will keep a stiff and cool northwest flow around. Highs today will be chilly with much of the region a good 10+° below seasonal averages.

Below: AIFS showing temperature departure from average this afternoon:

Heading into tonight, the ridge of high pressure to the west will move directly overhead of New England. This will allow for mainly clear skies and calm winds. This, in turn, allows for optimal radiational cooling over New England, which will allow temperatures to fall very quickly after sunset. On top of that, dew points will be in the teens to low 20s.

This is a perfect setup for temperatures to bottom out (relative to the time of year). Overnight lows will be in the 20s region-wide with some upper teens across the northern higher terrain. Some of the higher terrain in Vermont could come close to all-time lows for April 10th.

Below: CMC showing potential temperatures overnight tonight:

High pressure will shift offshore on Thursday as the next low pressure system approaches from the west. This will allow for a more southerly flow and warm air advection to take over, bumping up temperatures a notch. With high pressure offshore, it will likely result in a n onshore flow for coastal areas. This would normally cooler temperatures this time of year, but given the cold air mass already in place over New England, the onshore flow may help to moderate the air mass and allow for temperatures to get a notch milder than Wednesday all the way to the coast.

A weak system will be approaching later Thursday into Thursday night. This wave of low pressure will be weakening as it pushes toward New England. Trends have continued to show the system falling apart as it moves over New England and runs into the offshore high pressure. Scattered rain and elevation-based snow showers will occur Thursday night through Friday, becoming much more isolated by Friday afternoon. Maine will be the direst during this time.

Below: RGEM showing potential weather overnight Thursday into Friday morning (1st image) and Friday afternoon (2nd image):

Heading into Friday night and Saturday, a developing coastal storm off the Mid-Atlantic will very slowly move to the south of New England. This will bring a more substantial and widespread push of precipitation. Temperatures will likely be cold enough to support snow or a mix at the onset, especially for all higher terrain areas (Berkshires, Worcester Hills, Litchfield Hills, Greens, Whites). A gradual change to rain will occur from south to north and lower elevation to higher elevation as daytime heating tries to take hold during the day Saturday.

There's still general disagreement on the exact timing of this system, but precipitation should arrive to southern New England rather early Saturday morning. The shield of precipitation will gradually work northeast during the morning and into the afternoon. Precipitation will be the most widespread and longest lasting across southern New England. The system will remain to the south of New England, so the northward extent of precipitation remains rather uncertain.

At this point, all of New England will have the chance to at least see showers on Saturday, with eastern Maine possibly not seeing activity until later in the day Saturday. Again, the highest chance of a washout will be across southern New England and along the coastal plain of northern New England.

Below: Current precipitation forecast for Saturday through Sunday morning:

As far as the potential for wintry precipitation goes, it will be most likely at the onset of the system Friday night into Saturday morning. The amount of snow (or mixing) during the daytime Saturday will hinge on a couple factors. The main one will be precipitation rates. The heavier the precipitation is able to fall, the more wintry precipitation will be possible. Heavier rates will help pull the colder air down closer to the surface; should the precipitation become heavy enough, it could pull the colder air all the way down to the surface.

Naturally, the higher in elevation, the easier it would be to reach the surface. Valley locations and the coastal plain will likely have a very tough time seeing snow all the way to the surface. Precipitation onset time will also play into this potential, especially for Maine. Over much of Maine, the earlier in the day Saturday precipitation can arrive, the better chance for some elevation-based snow/mixing over rainy weather at the start and vice versa. Overall, this certainly won't be a major springtime snow event, but some minor accumulations in the mountains will be possible.

Below: Current probability of minor winter weather impacts Friday night to Saturday:

The system will likely slow down and may cutoff moving into Sunday. This would lead to continued cool, raw and showery weather for the day. Showers will be most likely closer to the coast on Sunday, but any details on Sunday remain low confidence. As of now, the system looks to clear out by Monday, allowing for milder and drier weather to return. With that said, cutoff lows have a tendency to move slower than initially expected, so Monday could trend cooler and cloudier.