DAYS 1-5 (MARCH 15-19)
Early this morning, a layer of marine stratus clouds and some patchy fog made for a grey start to the day across much of the region. Exception: Merrimack Valley / southern NH, where this layer didn’t reach, and once the sun rose above it in the sky to the east, it’s filtered by high clouds above. But some advancement of the stratus deck into that region can occur early on, before we see a thinning / breaking trend with some partial sun in other areas today. I don’t have faith in complete clearing, but we’ll see how much sun can manage to make its way through the clouds as we go through the day. An increasing southerly air flow as a warm front goes by starts to pull more low level moisture into our region with time, and this will start to initiate lower clouds again coming off the ocean to the south. This will become more pronounced tonight and Sunday with a stronger southerly wind. We should be dry (as in rain-free) over most areas through the daylight hours of Sunday, with the exception of a few sprinkles and drizzle as a result of that increasing low level moisture as we head through tonight and Sunday. The trade-off will be unseasonably warm air, with many areas exceeding 60 for high temps on Sunday. However, the air coming off the chilly water closer to the South Coast will have a modifying effect in those areas, which don’t make it to 60. The large storm system that has been impacting the middle of the US (Texas, Plains, Midwest) with everything from tornadoes and thunderstorms to dust storms to a snowstorm, depending on location, will track through the Great Lakes into Canada as we head through the weekend. While additional severe thunderstorms occur from the Midwest to Southeast today, we’ll not have to worry about that, only waiting for the cold front’s rain band to move into and through the region Sunday evening into Monday. This will be a slow process, and a wave of low pressure forming on the front as it starts to push off the East Coast may even prolong the rain a bit longer here into Monday, before some drying arrives from the west. The timing of this will determine whether or not we see any breaks / sun before sunset on St. Patrick’s Day. High pressure builds Tuesday and Wednesday with fair weather. Tuesday will feature a cool northwesterly breeze. Wednesday will have less wind overall, but a cooling coastal sea breeze. While Tuesday’s temperatures are more uniform for highs, Wednesday we can see a larger contrast from coastal to inland areas.
TODAY: Early to mid morning overcast with areas of fog except partial sun far northern MA and southern NH. Mostly cloudy to partly sunny thereafter. Highs 49-56, coolest coastal areas. Wind SE to S up to 10 MPH.
TONIGHT: Mostly cloudy. A patch of drizzle and areas of fog possible. Lows 44-51. Wind S up to 10 MPH.
SUNDAY: Mostly cloudy. A passing light rain shower possible. Highs 51-58 South Coast, 59-66 elsewhere. Wind S increasing to 10-20 MPH, gusts around 30 MPH.
SUNDAY NIGHT: Cloudy. Widespread rain showers. Slight chance of a thunderstorm. Lows 48-55. Wind S 10-20 MPH, higher gusts.
MONDAY: Cloudy with rain showers likely through mid afternoon, diminishing west to east, then late-day breaking clouds, especially west of I-95. Highs 55-62. Wind S 5-15 MPH, higher gusts, shifting to NW.
MONDAY NIGHT: Clearing. Lows 35-42. Wind NW 5-15 MPH, higher gusts.
TUESDAY: Mostly sunny. Highs 52-59. Wind NW 5-15 MPH, higher gusts.
TUESDAY NIGHT: Mostly clear. Lows 33-40. Wind NW to N diminishing to under 10 MPH.
WEDNESDAY: Mostly sunny. Highs 48-55 coast, 55-62 inland. Wind N up to 10 MPH becoming variable inland with coastal sea breezes developing.
DAYS 6-10 (MARCH 20-24)
The vernal equinox (astronomical start of spring) occurs at 5:01 a.m. EDT March 20. Our weather pattern during this period turns more unsettled, starting mild with one frontal system bringing some wet weather between late March 20 and early March 21. Additional rain/mix/snow showers possible with cooler weather after that.
DAYS 11-15 (MARCH 25-29)
Cooler and unsettled pattern indicated for late month.