Marine Weather and Tide Forecast for Pocasset, MA

KEY MESSAGES

- Gusty southerly winds with some showers and perhaps a few afternoon thunderstorms Thursday. Main threat for severe weather still looks to be to our west and south but is possible across SNE.

- Beautiful weather Fri into the weekend despite gusty west winds Fri-Sat. Highs mainly between 75 and 85 with low humidity.

- Potential for a much needed soaking rain to kick off the start of the next work week...But that is not set in stone.



DISCUSSION

KEY MESSAGE 1...Gusty southerly winds with some showers and perhaps a few afternoon thunderstorms Thursday. Main threat for severe weather still looks to be to our west and south but is possible across SNE.

After a mostly dry day Wednesday save for some isolated showers over western/central MA our next impactful bout of weather arrives overnight and Thursday. In the mid-levels a positively tilted trough digs into the eastern Great Lakes early Thursday moving then over New England later Thursday into Friday. This directs a plume of deep moisture and strong low to mid level winds overhead. A strong W/SW jet stretches from 850mb (50-60kts) to 500mb (80-95kts) contributing to some very strong wind shear values. 0-6km bulk shear values are on the order of 70-80kts with even more impressive low level shear values (0-1km SRH 300-400m2s2). The limiting factor for severe thunderstorm development will be (potentially) very marginal instability. The previously mentioned LLJ will act on an early morning warm front to bring a round of widespread showers and potentially some embedded thunderstorms after midnight through mid to late morning. These showers and associated lingering cloudcover will act to limit heating and destabilization for some time. Much will depend on if we get many breaks in the clouds in which highs initially expected in the 70s could jump up coincident with higher instability values. At the moment, thinking that the true warm sector/highest instability values, and greatest severe potential remains just to our south and west. However, it won't take much for such a borderline atmospheric setup to become much more volatile.
Historically even low instability environments have been able to be overcome by particularly strong shear, so a Slight Risk (level 2 of 5) of severe weather remains in effect. The greatest threat would be from damaging winds, then tornado potential given the extreme low level shear values. For SNE, the most likely intersection of instability and strong shear (aka greatest severe threat) would be western MA and western CT during the mid afternoon to early evening.
In sum, low confidence that severe weather materializes but high potential impact if it does. Timing is generally noon to 9pm (earlier west, later east).

Finally, regardless, Thursday will be gusty thanks to the strong LLJ overhead. Much will depend on amount of clearing and resultant diurnal heating as to how well the BL mixes, but BUFKIT soundings indicate potential for wind gusts of 25 to 35 mph, even up to 40 mph at times.

KEY MESSAGE 2...Beautiful weather Fri into the weekend despite gusty west winds Fri-Sat. Highs mainly between 75 and 85 with comfortable humidity.

A beautiful post-frontal airmass works into southern New England Fri and Sat. Low pressure tracking from Quebec into the Canadian Maritimes will result in gusty west winds of 25 to 35 mph Fri/Sat afternoons with perhaps even a few spots briefly gusting up to 40 mph. Winds should be a bit less on Sunday as the pressure gradient weakens.

Otherwise...beautiful weather expected Fri into the weekend with highs generally between 75 and 85 degrees and low humidity. Low temps will be pleasant too...mainly in the 50s to the lower 60s.

The weather will be dry for all intensive purposes. Some moisture starved northern stream energy may trigger a brief diurnally driven spot shower or two this weekend. But again it is pretty much a beautiful dry stretch of weather into the weekend.

KEY MESSAGE 3...Potential for a much needed soaking rain to kick off the start of the next work week...But that is not set in stone.

The potential continues for a much needed soaking rain to kick off the start of the next work week...But that will depend upon the track of low pressure. This still remains uncertain given these tracks are usually impacted by convective processes this time of year. Limited baroclinicity during the summer can also result in more difficulties...Not to mention we are still 5 days out in the future. Certainly the potential remains for a soaking rainfall and some of our guidance continues to indicate that potential...But whether or not that comes into fruition remains uncertain.

Drier and very pleasant summerlike weather should return Tue into Wed as high pressure builds in from the west. Temperatures look to be rather seasonable with comfortable humidity by the middle of next week.

AVIATION /18Z WEDNESDAY THROUGH MONDAY/
Forecaster Confidence Levels...

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

This afternoon...High Confidence.

VFR. Winds S 5-10 knots except for sea breezes along the immediate coast. A few afternoon/evening spot showers possible across the distant interior. Otherwise, dry weather continues.

Tonight...High Confidence.

VFR during the evening with some MVFR to localized IFR conditions developing toward daybreak across parts of the interior. Scattered showers develop toward morning with the focus across interior MA. Winds becoming SE at 5 to 10 knots late.

Thursday...Moderate confidence.

Areas MVFR/IFR in stratus towards the Berkshires and south coast becoming more widespread during the day. SHRA with a risk for -TSRA in the afternoon and evening. Gusty SW winds for all terminals and LLWS also possible towards the Cape and islands.

Thursday night...High confidence.

VFR. SHRA/TSRA exiting late evening/early overnight. VFR to start except for southeast MA terminals which improve from IFR/MVFR to VFR by 06z with departing showers. SW winds 5-10 kts gusting 15-25 kts early, turning westerly and diminishing through the night.

KBOS Terminal...High confidence in TAF.

KBDL Terminal...High confidence in TAF.

Outlook /Wednesday through Monday/...

Wednesday through Friday Night: VFR. Breezy.

Saturday: VFR. Windy with local gusts up to 30 kt.

Saturday Night: VFR. Breezy.

Sunday: VFR. Breezy. Slight chance SHRA.

MARINE
Forecaster Confidence Levels...

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

Through Thursday night: High confidence.

Gusty southwest winds expected Thursday. Much will depend on how warm we can get. Have high confidence in at least Small Craft Advisory conditions, with moderate confidence for gale force gusts across some of the eastern coastal waters. Gale Watches expanded to interior easter MA waters where proximity to land/better warming may help mix down marginal gale force winds.

Outlook /Thursday Night through Monday/...

Thursday Night: Low risk for Small Craft Advisory winds with gusts up to 30 kt. Rough seas up to 8 ft. Slight chance of rain showers.

Juneteenth: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Rough seas up to 7 ft.

Friday Night through Saturday: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Seas up to 5 ft.

Saturday Night: Winds less than 25 kt. Seas up to 5 ft.

Sunday: Winds less than 25 kt. Areas of seas approaching 5 ft.

BOX WATCHES/WARNINGS/ADVISORIES
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory from 11 AM to 7 PM EDT Thursday for ANZ230-236-251.
Gale Watch from Thursday morning through Thursday evening for ANZ231-234.
Small Craft Advisory from 11 AM Thursday to 1 AM EDT Friday for ANZ232-233.
Small Craft Advisory from 11 AM Thursday to 8 PM EDT Friday for ANZ235-237-255-256.
Gale Watch from Thursday morning through Thursday evening for ANZ250-280.
Small Craft Advisory from 2 PM Thursday to 8 PM EDT Friday for ANZ254.