DAYS 1-5 (JUNE 14-18)

High pressure will dominate the weather today through Wednesday. Today’s weather will be warm and dry as the high center in control will be to our west and the air mass in place has been warmed by June sunshine. This high center will weaken and give way to a slightly stronger one in southeastern Canada Wednesday, sending a back-door cold front through the region early in the day and setting up another fair but cooler day, with a northeasterly air flow. This will settle down as the day goes on and the high center sinks southward, but the resultant weaker wind field would allow a sea breeze to develop anyway, so the general onshore flow will continue. High pressure shifts offshore to the southeast of New England by early Thursday at which time a broad low pressure area will be heading east northeastward through the Great Lakes, eventually to cross southeastern Canada Thursday night into Friday while its track turns more east to southeast. Clouds increase and humidity starts to rise during Thursday, and a round of showers can be expected with the warm front some time Thursday evening or night, at which time we’ll get into a wedge of warmth and high humidity, so temperatures at night will not fall all that much. Friday, a cold front will swing through from northwest to southeast, and the timing of this front will determine the coverage and strength of showers and thunderstorms that accompany it. After any overnight / early morning activity departs, we will see breaks in the clouds and some sunshine, which will heat the atmosphere and destabilize it, with the warm and muggy air in place, but the cold front’s timing looks fairly early to me – late morning to midday for areas northwest of Boston and early to mid afternoon from the Boston area southeastward. There are still a few days to fine-tune this, but if this idea is right, showers/storms may be limited initially, and most widespread / strongest over southeastern MA and RI. As they got closer to Cape Cod we’d then probably see the marine stabilizing influence take over and they’d weaken. While Friday will stay pretty warm throughout the day into the evening, we will see the dew point start to fall with the passage of the cold front, so the end of the day will be more comfortable than the start. Also, there will be a fair amount of wind developing Thursday and continuing Friday with the passage of this system and a tighter pressure gradient. Saturday, the upper low associated with this departing feature will slow down and likely come to a stop, far enough offshore that we avoid an overcast and rainy set-up, but close enough that we will have to watch for at least some clouds to build and the possibility of pop up showers and thunderstorms. Don’t go cancelling any outdoor plans over this, however.

TODAY: Mostly sunny. Highs 79-86, but may turn cooler immediate coast afternoon. Wind NW 5-15 MPH, but sea breezes may develop right at the shore.

TONIGHT: Partly cloudy. Lows 57-64. Wind N under 10 MPH.

WEDNESDAY: Partly cloudy early, then mostly sunny. Highs 73-80, coolest coast. Wind NE 5-15 MPH morning, E up to 10 MPH afternoon.

WEDNESDAY NIGHT: Mostly clear. Lows 55-62. Wind E to variable under 10 MPH.

THURSDAY: Increasing clouds. Highs 75-82, coolest coast. Wind SE up to 10 MPH morning, S 10-20 MPH with higher gusts afternoon.

THURSDAY NIGHT: Mostly cloudy with showers likely and a chance of thunderstorms. Areas of fog. Humid – dew point 60+. Lows 61-68. Wind SW 5-15 MPH, higher gusts.

FRIDAY: Partly cloudy. A shower or thunderstorm possible late morning through mid afternoon from northwest to southeast across the region. Any thunderstorms may be strong. Humid morning – dew point 60+, then lowering humidity. Highs 81-88. Wind W-NW 5-15 MPH, gusty.

FRIDAY NIGHT: Clear. Lows 58-65. Wind NW 5-15 MPH.

SATURDAY: Sun/cloud mix. Isolated showers and thunderstorms possible. Highs 75-82. Wind N 5-15 MPH, higher gusts.

DAYS 6-10 (JUNE 19-23)

We’ll be on the western side of upper level low pressure on June 19 with a chance of a pop up shower, otherwise mostly dry and fairly cool weather. After this, the pattern should open up again with a return to a northwesterly flow, variable temperatures with no high heat, mostly dry but a chance of a passing shower or t-storm from time to time with disturbances moving along the flow as we finish up spring and welcome summer (solstice June 21).

DAYS 11-15 (JUNE 24-28)

Outside shot of a bit of rain to start this period as there are some hints of a stronger disturbance coming along the continued northwest flow pattern, otherwise more of the same heading into late June.