textproduct: Boston / Norton

WHAT HAS CHANGED

No significant changes to the forecast.

KEY MESSAGES

- Spot shower or thunderstorm possible today. Otherwise, a mainly dry and pleasant late-summer day.

- Seasonable temperatures and dry weather this weekend.

- Cloudy and unsettled early to mid next week with several opportunities for showers and storms, but the timing of them is uncertain.

DISCUSSION

KEY MESSAGE 1...Spot shower or thunderstorm possible today. Otherwise, a mainly dry and pleasant late-summer day.

Latest guidance suite continued to depict stratus overspreading portions of southern New England early this morning. based on the latest observations, this may be a little aggressive. That said, there are still signs of stratus trying to develop, so it may just be a question of timing. Will continue to monitor these clouds early this morning.

Expecting any early low clouds to break up and lift. Not sure how much sunshine we'll see, as mid and high level clouds should also drift northeast. Thinking temperatures will be near normal, but it will remain humid. A cold front moves in this morning into early afternoon, providing a focus for isolated to scattered showers and perhaps a garden-variety thunderstorm or two. Much of the day should remain dry, with any shower or thunderstorm activity brief and localized.

This cold front clears the coast this evening, with winds shifting to the northwest behind it. A more comfortable and less humid air mass arrives overnight into early Saturday.

KEY MESSAGE 2...Seasonable temperatures and dry weather this weekend.

High pressure is overhead for Saturday, then moves offshore Sunday. Noticeably lower humidity and mainly clear skies are expected.

KEY MESSAGE 3...Cloudy and unsettled early to mid next week with several opportunities for showers and storms. However, the timing of them is uncertain.

A consistent theme developed over the past few days, one of a backdoor cold front moving west across our region early next week. That said, there remain differences in how fast and far this front will make it before stalling in the Monday to Wednesday timeframe. As long as this front remains nearby, there should be several opportunities for showers, and possibly a few thunderstorms as well. A low pressure moving from southeast Canada across northern New England may finally move this front out of our region sometime on Thursday. Until this happens, high temperatures should be slightly below normal with low temperatures slightly above normal most of next week.

AVIATION /12Z FRIDAY THROUGH TUESDAY/

Forecaster Confidence Levels...

Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent.

Today...High confidence in trends, lower confidence in storm coverage.

Conditions improve to VFR with ceilings 050-080 after 14-16z. Pop-up TSRA possible between 18-00z, which may result in brief MVFR/IFR conditions. Light W/SW winds become WNW by late afternoon.

Tonight...High confidence.

VFR ceilings for most, though MVFR possible along the immediate south coasts of RI/MA, Cape Cod, and the Islands. Light NW winds.

Saturday...High confidence.

VFR. Light N to NE winds.

KBOS Terminal...Moderate confidence. Stratus at times early this morning at MVFR levels with TEMPO IFR pre-dawn. VFR returns early this morning. Possible SHRA/TS between 18z-21Z today, perhaps as late as 00z Sat.

KBDL Terminal...Moderate confidence. Still a low chance for TSRA 18z-20z today.

Outlook /Saturday Night through Tuesday/...

Saturday Night: VFR.

Sunday: VFR. Breezy.

Sunday Night: VFR. Breezy. Slight chance SHRA.

Monday: VFR. Slight chance SHRA.

Monday Night: VFR. Slight chance SHRA, slight chance TSRA.

Tuesday: Mainly VFR, with local MVFR possible. Chance SHRA, slight chance TSRA.

MARINE

Forecaster Confidence Levels...

Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent.

Through Saturday...High confidence.

Showers and few thunderstorms pass by south and east of Nantucket early this morning. A cold front should cross the waters this evening, followed by high pressure Saturday. Relatively light winds and seas during this time.

Outlook /Saturday Night through Tuesday/...

Saturday Night through Sunday: Winds less than 25 kt.

Sunday Night: Winds less than 25 kt. Chance of rain showers.

Monday through Tuesday: Winds less than 25 kt. Slight chance of rain showers.

BOX WATCHES/WARNINGS/ADVISORIES

CT...None. MA...None. RI...None. MARINE...None.