DAYS 1-5 (AUGUST 9-13)
A westerly air flow behind departing low pressure provides a nice day today with a sun/cloud mix and lower humidity. The breeze will settle down later as a bubble of high pressure to the southwest moves close, then this high will scoot off to the east on Thursday, and after a tranquil night tonight, we’ll experience a southerly breeze tomorrow, not too strong, but one that will transport higher dew point air into the region ahead of the next approaching disturbance. This disturbance has support from a pretty strong jet stream and has a bit of a complex set-up involved with it. I’m looking for a trough to approach later in the day with the possibility of some combination dynamic / diurnal thunderstorms to fire off mainly west of I-495, though this activity should be fairly isolated. At the same time a wave of low pressure will be racing eastward toward southern New England. This system is progged by the majority of guidance to have its center pass somewhere over southern New England late Thursday night to early Friday. While a swath of showers will accompany it, near and just south of its track will find support for individual convective showers and thunderstorms which can display rotation and a possible tornado threat. This is something we’ll have to keep a close eye on from dusk to dawn. Improvement follows quickly on Friday as the disturbance exits the region. Expect a day somewhat similar to the one we will experience today. The weekend looks pretty decent as it stands now, but we’ll have to watch the next disturbance and its timing. I think this one is more of a trough passage sometime between Saturday late night and Sunday midday. That time window would be away from maximum solar heating and may limit the shower and thunderstorm chance. So if you have weekend plans, just keep in mind that somewhere in there is the chance of an interruption in outdoor plans but for the most part it’s looking pretty decent.
TODAY: Sun/cloud mix. Highs 77-84. Dew point around 60. Wind W 5-15 MPH with higher gusts, diminishing somewhat by the end of the day.
TONIGHT: Mostly clear. Fog patches in lower elevations. Lows 60-67. Dew point near 60. Wind W diminishing to under 10 MPH.
THURSDAY: Sun dominant first half of day, then variably cloudy afternoon. Late-day thunderstorms possible west of I-495. Evening showers eastern CT to RI. Highs 80-87, a bit cooler South Coast. Dew point 60+. Wind S 5-15 MPH becoming variable around 10 MPH by evening.
THURSDAY NIGHT: Mostly cloudy. Showers likely. Downpours and thunderstorms possible mostly south of I-90 which may have the ability to produce isolated tornadoes. Areas of fog forming. Lows 62-69. Dew point 60+. Wind variable 5-15 MPH, can be briefly strong and gusty near any downpours/thunderstorms mainly south of I-90.
FRIDAY: Sun and passing clouds. Highs 78-85. Dew point near 60. Wind W 5-15 MPH.
FRIDAY NIGHT: Partly cloudy. Patchy ground fog. Lows 62-69. Dew point lower 60s. Wind SW under 10 MPH.
SATURDAY: Partly sunny. Late-day shower or thunderstorm possible southwestern NH / central MA / eastern CT. Highs 80-87. Dew point 60+. Wind SW 5-15 MPH.
SATURDAY NIGHT: Variably cloudy. A shower or thunderstorm possible. Lows 62-69. Dew point near 60. Wind SW 5-15 MPH.
SUNDAY: Partly sunny. Chance of a shower, especially in the morning. Highs 78-85. Dew point near 60. Wind W 5-15 MPH.
DAYS 6-10 (AUGUST 14-18)
A generally zonal flow pattern is expected, disturbances passing by with a couple shower and thunderstorm chances – most likely August 15 & 17. Temperatures near to slightly above normal.
DAYS 11-15 (AUGUST 19-23)
A weaker westerly flow and a little more high pressure domination overall reduces shower/storm opportunities and allows for a little more late summer heat potential during this period.