


Area Forecast Discussion
Issued by NWS Boston, MA
Issued by NWS Boston, MA
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877 FXUS61 KBOX 140407 AFDBOX Area Forecast Discussion National Weather Service Boston/Norton MA 1207 AM EDT Sat Jun 14 2025 .SYNOPSIS... A weak upper level disturbance brings clouds and periods of rain tonight into the first half of Saturday. Precipitation gradually winds down Saturday afternoon with drier northwest flow aloft. An onshore flow and low stratus keeps temperatures well below average through Sunday. Drier conditions return Sunday but still cool, then a warming trend begins Monday with a return to summer like temperatures by Thursday and Friday. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... Key Messages: * Clouds lower and thicken from W to E as a weak disturbance approaches from the west. A weak mid-level shortwave is still on track to impact the region starting tonight. Influence from high pressure will wane through the overnight and clouds will lower and thicken from west to east. Mid- level dry air should hold showers off until after midnight. Lows tonight will fall into the mid 50s as a cool onshore flow develops. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/... Key Messages: * Periods of showers continue through the first half of the day * Onshore flow keeps temperatures well below average Details... Saturday... Periods of showers will likely continue through the first half of Saturday. Ensemble guidance keeps rainfall totals generally at or below 0.25" for the region. These lower totals are the result of weak forcing and little instability despite PWAT values rising to between 1.4 and 1.6 inches. Precipitation gradually winds down from north to south as northwesterly flow at the mid-levels gradually dries the column. Unfortunately, this drier layer will likely only make it down to around 800mb by Saturday evening. This will translate to a rather dreary day, with high temperatures struggling to get into the lower 60`s for most of us. For many locations, this will be the the Saturday in a row with measurable rainfall. && .LONG TERM /SUNDAY THROUGH FRIDAY/... Key Messages: * Dry and cool Sunday * Warming trend starts Monday, becoming hot and humid for the second half of next week Seeing some modest signals for warmer and more humid conditions next week, but not yet looking like it will be anything really atypical for summer. Not expecting a washout of a week either, as there should be many hours of precipitation-free weather. The first chance of showers will be Sunday night into Monday as weak low pressure moves by to our south. Trends have been slightly farther south with the recent guidance, which would result in lower rainfall chances for us here in southern New England. Have the highest rainfall chances towards the south coast, including the Cape and islands. Again, not looking like a washout during this time. A low pressure moving across the Great Lakes into Canada should push a warm front across our region some time Wednesday into Wednesday night. This could trigger a few showers as it does. A greater risk for mainly afternoon and evening showers is expected Thursday ahead of the cold front of this low pressure. Slightly cooler and less humid conditions anticipated for next Friday at this time. && .AVIATION /04Z SATURDAY THROUGH WEDNESDAY/... Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. 06z TAF Update: Through tonight...High confidence. VFR, but lowering cigs tonight with areas of MVFR and scattered showers developing mainly after 06z from SW to NE. Saturday...Moderate confidence. MVFR/IFR with light rain showers in the morning, drying up in the afternoon with the exception of the Cape and Islands where rain will last into the afternoon Saturday night...Moderate Confidence MVFR/VFR. light NE winds. KBOS Terminal...High confidence in TAF. Off and on showers through about 11z this morning, then more steady light rain expected after 11z. CIGS should stay MVFR despite the onshore flow as high pressure to the north brings in drier air. KBDL Terminal...High confidence in TAF. Off and on showers mainly between 10-14z, although could linger through 17z. CIGS should remain MVFR with periods of IFR possible Outlook /Sunday through Wednesday/... Sunday: Mainly VFR, with local MVFR possible. Sunday Night through Monday: Mainly VFR, with local MVFR possible. Slight chance SHRA. Monday Night through Tuesday: Mainly VFR, with local IFR possible. Tuesday Night: Mainly VFR, with local IFR possible. Slight chance SHRA. Wednesday: Breezy. Slight chance SHRA. && .MARINE... Forecaster Confidence Levels: Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. Today through Saturday... E-SE winds developing this evening and continuing through Saturday. Speeds below 20 kt and seas below SCA thresholds. Scattered showers developing tonight with more widespread showers possible Sat over south coastal waters. Outlook /Sunday through Wednesday/... Sunday: Winds less than 25 kt. Areas of seas approaching 5 ft. Sunday Night: Winds less than 25 kt. Areas of seas approaching 5 ft. Slight chance of rain showers. Monday: Winds less than 25 kt. Seas locally approaching 5 ft. Slight chance of rain showers. Monday Night: Winds less than 25 kt. Slight chance of rain showers. Tuesday through Tuesday Night: Winds less than 25 kt. Wednesday: Winds less than 25 kt. Seas locally approaching 5 ft. Slight chance of rain showers. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...None. RI...None. MARINE...None. && $$ SYNOPSIS...Belk/FT NEAR TERM...Hrencecin/FT SHORT TERM...Hrencecin/FT LONG TERM...Belk AVIATION...KP MARINE...Belk/FT