DAYS 1-5 (MAY 8-12)

A low-amplitude upper level trough will swing through our region today into Saturday. Surface high pressure keeps our weather mostly dry initially today but the colder air aloft will trigger diurnal cloud development later this morning through this afternoon, and some of these clouds can grow enough to produce some convective shower activity, so keep an eye out for a spot passing shower here and there. This activity wanes toward sunset and these clouds decrease this evening, but at the same time we’ll see high cloudiness start to fan in from the west ahead of another disturbance sliding our way. This one passes by the region on Saturday with a period of rain mainly in the afternoon to early evening hours. Timing-wise, there is not a lot of change to what I said yesterday, with rain expected to arrive well southwest of Boston by late morning and reach the NH Seacoast region by early or mid afternoon, so the further north and east you are the more “dry time” you get in the early part of the day before it gets wet. Saturday night, the main rain area exits, but a passing trough can trigger an additional shower, maybe even a thunderstorm in a few locations. Coverage would be low on this, but any area that saw one could have briefly heavy rain. This leads to a much nicer and warmer day on Sunday with a west to southwest air flow. There will still be some chilly air aloft so I don’t expect full sunshine, but a mix of sun and clouds, and a few of the latter can build enough to release a pop-up shower, but coverage would be very low, so I wouldn’t cancel any outdoor plans – just keep an eye on the sky during the afternoon and early evening. The active pattern we’re in sends another wave of low pressure our way for some rainy weather on Monday, before we clear again for Tuesday, with a trend to cooler conditions early next week as well, in response to another upper low moving in from the west.

TODAY: Sunny start, then a sun / cloud mix with a slight chance of a passing shower mid to late afternoon. Highs 58-65. Wind NW 5-15 MPH, gusts 20-25 MPH.

TONIGHT: Partly cloudy early evening, mostly clear late evening, then increasing high clouds overnight. Lows 38-45. Wind variable up to 10 MPH.

SATURDAY: Overcast thickens. Rain arrives southwest to northeast mid morning through early afternoon, continuing thereafter. Highs 57-64. Wind variable up to 10 MPH.

SATURDAY NIGHT: Mostly cloudy with a chance of rain early, then clearing. Patchy fog. Lows 47-54. Wind variable to SW up to 10 MPH.

SUNDAY: Partly sunny. A pop-up shower possible. Highs 66-73 except cooler South Coast / Cape Cod. Wind SW 5-15 MPH.

SUNDAY NIGHT: Increasing clouds. Lows 48-55. Wind S to SE up to 10 MPH.

MONDAY: Cloudy. Rain likely. Highs 55-62, coolest coast. Wind E 5-15 MPH.

MONDAY NIGHT: Rain ends. Clearing overnight. Lows 40-47. Wind N 5-15 MPH.

TUESDAY: Sun / cloud mix. Highs 57-64. Wind NW 5-15 MPH.

DAYS 6-10 (MAY 13-17)

Early to mid period fair weather with a brief milder trend. Later-period unsettled weather potential with low pressure trough in the region, with a return to cooler conditions.

DAYS 11-15 (MAY 18-22)

Similar pattern expected with early to mid period fair weather and later-period unsettled weather returning. Temperatures start on the cooler side then trend milder.