Area Forecast Discussion

648 FXUS61 KBOX 181114 AFDBOX Area Forecast Discussion National Weather Service Boston/Norton MA 714 AM EDT Sat Oct 18 2025 .SYNOPSIS... High pressure takes a hold of the weather pattern this weekend bringing less wind and warmer afternoon temperatures. A Strong Frontal system begins to approach the region on Sunday, bringing gusty southerly winds with above-normal temperatures. The frontal system arrives Monday morning, bringing rain and a chance for thunderstorms. The pattern remains unsettled as we head into the middle of next week. && .NEAR TERM /THROUGH TONIGHT/... Upper-level ridge axis moves directly overhead tomorrow, while high pressure just off shore of the Carolinas begins to retreat further south. What this means for us is another pleasant day with highs again reaching the low to mid 60s. Skies will start the day off mostly sunny, but high clouds begin to filter in by early afternoon as mid to upper level moisture arrives with the ridge axis. It will be noticeably less windy today, with light and variable to calm winds across the region. && .SHORT TERM /SUNDAY/... Tonight: Winds aloft begin to flip SW overnight, advecting in warmer air aloft with 850mb temps increasing to +11C. Despite calm winds at the surface, high clouds and warming temps aloft will keep overnight lows a bit warmer tonight, in the mid to upper 40s. Dewpoints gradually rise overnight, which could lead to patchy radiation fog in low-lying areas. Tomorrow: Mid-level winds continue to increase tomorrow ahead of a robust shortwave over the Ohio River Valley. Once diurnal heating kicks in on Sunday, the winds aloft will begin to mix down, bringing southerly gusts of 15-20mph. The southerly winds and WAA will help warm temps into the upper 60s to low 70s. High clouds continue to stream in ahead of the shortwave with mainly filtered sunshine throughout the day. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... Key Messages: * Looking unsettled next week as multiple shortwaves move through the region. Timing questions remain with the passage of a cold front and secondary low pressure some time Sunday night into Monday. The 17/12Z NAM was on the more progressive end of the guidance. Given the synoptic pattern of a high pressure to the east and a secondary low pressure along this front, favored a slower timing that was more in line with the 17/12Z GFS and CMC solutions. This keeps most of Sunday dry, with showers arriving from west to east after sunset. Expecting showers across most of our region by the time of the Monday morning commute. Beyond this time, the timing of showers remains uncertain. Most of the 17/12Z guidance suite develops more of a mid level cutoff, but cannot agree on where this cutoff will be. This cutoff then appears like it will get kicked out over the Atlantic by a more potent mid level trough midweek. This pattern typically leads to a prolonged period of unsettled weather. Looking like a trend toward below normal temperatures next week with periods of showers. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... Forecaster Confidence Levels... Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Today and Tonight...High Confidence. VFR. Light and variable winds. Localized sea breezes develop late morning to early afternoon. There may be some localized ground and valley fog overnight Saturday into Sunday. Sunday... High Confidence VFR. Increasing southerly winds gusting up to 15-20 knots. KBOS Terminal...High Confidence in TAF. VFR. Sea breeze kick in early in around 16z. KBDL Terminal...High Confidence in TAF. VFR. Light winds under 5 knots. Outlook /Sunday Night through Wednesday/... Sunday Night: Mainly VFR, with local IFR possible. Windy with gusts up to 30 kt. Chance SHRA. Monday: Mainly MVFR, with local IFR possible. Windy with gusts up to 35 kt. Chance SHRA, slight chance TSRA. Monday Night: VFR. Windy with local gusts up to 30 kt. Chance SHRA. Tuesday: VFR. Breezy. Tuesday Night: VFR. Chance SHRA. Wednesday: Mainly VFR, with local MVFR possible. Breezy. Chance SHRA. && .MARINE... Forecaster Confidence Levels... Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. Through Sunday...High confidence. High pressure brings calm winds and decreasing seas today and tonight, ranging from 3-6 feet. Winds gradually flip south on Sunday and begin increasing to 15-20knots on Sunday. Seas remain around 3-6 feet Outlook /Sunday Night through Wednesday/... Sunday Night: Low risk for Small Craft Advisory winds with gusts up to 30 kt. Seas up to 5 ft. Chance of rain showers. Monday: Low risk for gale force winds with gusts up to 40 kt. Areas of rough seas. Rain showers likely, slight chance of thunderstorms. Monday Night: Winds less than 25 kt. Areas of rough seas. Chance of rain showers, slight chance of thunderstorms. Tuesday: Winds less than 25 kt. Seas up to 5 ft. Slight chance of rain showers. Tuesday Night: Winds less than 25 kt. Areas of seas approaching 5 ft. Chance of rain showers. Wednesday: Winds less than 25 kt. Areas of seas approaching 5 ft. Chance of rain showers, slight chance of thunderstorms. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...None. RI...None. MARINE...Small Craft Advisory until 8 AM EDT Sunday for ANZ250-254-255. && $$ SYNOPSIS...Belk/KP NEAR TERM...KP SHORT TERM...KP LONG TERM...Belk/KP AVIATION...McMinn/KP MARINE...KP NWS BOX Office Area Forecast Discussion