FXUS61 KBOX 261913

AFDBOX



Area Forecast Discussion

National Weather Service Boston/Norton MA

313 PM EDT Thu Jun 26 2025



.SYNOPSIS...

High pressure builds into the Gulf of Maine tonight into Friday,

maintaining mostly cloudy conditions, cooler temperatures and 

modest onshore breezes. A warm front tries to lift northward

Saturday with a risk for showers and thunderstorms, along with

warmer and more humid weather for the southern half of Southern

New England. Seasonably warm and dry for Sunday. Temperatures

then warm up into the mid to upper 80s again early next week, 

along with daily chances for showers and thunderstorms.



&&



.NEAR TERM /THROUGH TONIGHT/...

305 PM Update:



Key Messages: 



* Cloudy with continued onshore flow allowing for cooler

  nighttime lows upper 50s/low 60s. 



* Hit or miss rain showers thru midnight but majority of

  Southern New England stays dry.



Details:



Today's been quite a bit cooler and noticeably less humid,

driven by NE onshore flow with sfc ridging extending into

ME/northern NH. And by quite a bit cooler, 24 hour temperature

anomalies are around 20-25 degrees cooler. Considerable 

cloudiness has also resulted, and that will continue into 

tonight as a weak disturbance aloft working through central NY 

moves ESE through Southern New England during the first part of 

the evening. Radar mosaic is showing some returns but most of 

these showers are having a tough time reaching the ground. 

Wouldn't rule out a passing shower thru midnight but think the

radar presentation's bark is worse than the bite and the 

majority of the time is dry. High pressure then makes greater

southward inroads during the overnight with any light rain

showers pulling southward/offshore, with dry weather. Still

overall cloudy tonight with lows in the upper 50s to lower 60s 

with a continued E to NE wind. 





&&



.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...

305 PM Update:



Key Messages: 



* Partly to mostly cloudy Friday, peeks of sun late in the day.

  Highs in the upper 60s to mid 70s.



* Increasing clouds and possible showers Friday night, starting

  to turn a little more humid but still tolerable. 



Details: 



A 1024 mb sfc high pressure will be building SE from ME/NH with

ridging extending westward from it to the Berkshires. It now

looks as though Friday ends up being drier than not, with the

better chance for rain showers being in the narrow/pinched warm

sector west of the Berkshires and Litchfield Hills. Although we

start off mostly cloudy, it's possible eastern areas could see

some breaks in the cloudiness toward some peeks of sun during

the afternoon. Think there should be enough breaks in cloudiness

to allow highs to rise into the upper 60s to mid 70s with

tolerable levels of humidity (dewpoints in the lower to mid

50s). 



Increased cloud cover toward overcast then returns Fri evening,

along with a rise in dewpoints/humidity level in the overnight 

as a warm front tries to lift northeastward. That being said,

with rain across interior northern New England falling into the

ridge helping to reinforce it, I'm not optimistic we'll truly

break out into the warmer and significantly more humid airmass

that lies well to our south and west. Still, increasing risk for

showers arriving toward the second half of the overnight, with

lows in the upper 50s to lower 60s. 



&&



.LONG TERM /SATURDAY THROUGH WEDNESDAY/...

Key Messages: 



* Below normal temperatures remain on Saturday, but a return to the 

  summer warmth Sunday though next week.   



* Best chance for showers comes Friday night into Saturday. 



As discussed prior, the mid-level ridge flattens and flow becomes 

nearly zonal. This allows for shortwaves to pass through the region 

and bring shower chances Friday night into Saturday, though there is 

still uncertainty withthe heaviest rainfall, in generally it does 

look to stay across northern New England, but the ensembles do 

show probs of 0.5", the GEFS at 40-60%, ENS does not show this, 

but has even lower probabilites of 0.1" at 20-40%, while the CMC

has 10-30% of 0.5" and +70% of 0.1". Something to watch, though

the better forcing does look to be in northern New England. 

Don't go canceling any outdoor events just yet. Briefly drier 

late Sunday into Monday, followed by a storms on Tuesday with a 

frontal passage. 



Temperature-wise, onshore flow provides cool temperatures Saturday, 

highs in the low to middle 70s Saturday. A warm up follows Sunday 

through midweek, summer temperatures return with highs in the low-

80s on Sunday. Then early next week highs return to the middle and 

upper 80s, along with dew points nearing 70F. It remains possible 

Monday and Tuesday could approach the low 90s, ensembles show 

+90F probabilites are between 30-50% across parts of southern 

New England.



&&



.AVIATION /18Z THURSDAY THROUGH MONDAY/...

Forecaster Confidence Levels...



Low - less than 30 percent. 

Moderate - 30 to 60 percent. 

High - greater than 60 percent.



18Z TAF Update: 



Through Tonight: High confidence. 



Mainly BKN/OVC VFR bases; could be some passing, spotty rain 

showers moving southeast rest of the afternoon thru about 04z 

Fri. However these showers should be light enough to not 

restrict visby. NE to E winds around 10 kt thru this evening.



Friday: High confidence. 



VFR continues, with dry weather. E to SE winds 5-10 kt. 



Friday Night: Moderate confidence. 



VFR early, although categories deteriorate from west to east

after 03z to IFR levels as stratus develops along with areas of

mist/fog. SE winds around 5 kt.



KBOS Terminal...High confidence in TAF.



KBDL Terminal...High confidence in TAF.



Outlook /Saturday through Monday/... 



Friday Night: Mainly VFR, with local IFR possible. Chance SHRA.



Saturday: Mainly IFR, with local MVFR possible. Breezy. Chance

SHRA, chance TSRA, patchy BR.



Saturday Night: IFR. Chance SHRA, slight chance TSRA, patchy

BR.



Sunday: Mainly VFR, with areas IFR possible. Slight chance

SHRA, patchy BR.



Sunday Night: Mainly VFR, with areas IFR possible. Patchy BR.



Monday: VFR. 



&&



.MARINE...

Forecaster Confidence Levels...



Low - less than 30 percent. 

Medium - 30 to 60 percent. 

High - greater than 60 percent.



NE to E winds range from 15-25 kt, with waves 3-5 ft tonight 

through Friday night. Strongest winds and highest seas over the 

southern outer waters. Issued SCA through Friday on the southern

outer waters, though conditions are somewhat borderline. Mainly

dry weather, although could see some passing showers tonight 

but shouldn't restict visbys. 



Outlook /Saturday through Monday/...



Friday Night: Winds less than 25 kt. Seas locally approaching

5 ft. Chance of rain showers. 



Saturday: Winds less than 25 kt. Seas locally approaching 5 ft.

Chance of rain showers, slight chance of thunderstorms, patchy

fog. Visibility 1 to 3 nm.



Saturday Night: Winds less than 25 kt. Areas of seas

approaching 5 ft. Chance of rain showers, chance of

thunderstorms, patchy fog. Visibility 1 to 3 nm.



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

Chance of rain showers, patchy fog. Visibility 1 to 3 nm.



Sunday Night through Monday: Winds less than 25 kt. Areas of

seas approaching 5 ft. Patchy fog. Visibility 1 to 3 nm.



&&



.BOX WATCHES/WARNINGS/ADVISORIES...

CT...None.

MA...None.

RI...None.

MARINE...Small Craft Advisory from 8 PM this evening to 8 PM EDT Friday 

     for ANZ255-256.



&&



$$



SYNOPSIS...Loconto/McMinn

NEAR TERM...Loconto

SHORT TERM...Loconto

LONG TERM...McMinn

AVIATION...Loconto/McMinn

MARINE...Loconto/McMinn

