AFDBOX Area Forecast Discussion National Weather Service Boston/Norton MA 729 PM EDT Wed Mar 25 2026 .WHAT HAS CHANGED... No major changes since Wednesday morning update. && .KEY MESSAGES... - Mild temperatures Thursday will be followed by a soaking rain Thursday night into Friday with cooler temperatures to follow - Colder and blustery conditions to start the weekend with gradual improvement starting late Sunday or early Monday. && .DISCUSSION... KEY MESSAGE 1... Mild temperatures Thursday will be followed by a soaking rain Thursday night into Friday, with cooler temperatures returning for the weekend. A few showers are possible tonight into early Thursday morning, but otherwise a quiet period is expected. A surface low pressure system tracking east across Ontario and Quebec will lead to increasing south to southwest winds during the day Thursday. An impressive 4060 kt low-level jet at 925 hPa will support strong warm air advection, allowing 925 hPa temperatures to rise to around 10C. With sufficient diurnal mixing, especially across the interior, surface temperatures should reach the low to mid 60s. A few locations in the Connecticut River Valley could even approach 70F. The South Coast, Cape, and Islands will be cooler, generally in the mid to upper 50s, due to persistent onshore flow. Thursday night, a cold front associated with the low to our north will move through southern New England, bringing a period of soaking rain. While not a washout, most locations are expected to receive around 0.25 to 0.5 inches of rainfall. Winds will shift to the northwest behind the front, ushering in cooler air as 925 hPa temperatures fall to around 0C by mid-morning Friday. This will set the stage for cooler conditions heading into the weekend. KEY MESSAGE 2...Colder and blustery conditions to start the weekend with gradual improvement starting late Sunday or early Monday. Once the cold front moves offshore on Friday, a drier airmass will push into southern New England. Winds will pick up as the boundary layer becomes well mixed throughout the day, with 20-30mph winds possible. As this drier airmass moves through, it will also bring dropping 850mb temps with the latest round of ensemble and deterministic guidance indicating temps dropping down to around -15C roughly a -15C to -17C temperature anomaly. Given the arrival time of this airmass, Friday`s high temps will likely occur early in the morning before falling throughout the day. Highs struggle into the upper 30s to lower 40s on Saturday and Sunday with deep NW flow and prolonged 850mb temps <-10C. Southern New England will see gradual improvements starting Monday as high pressure moves offshore. Starting to keep an eye on another cold front possibly dropping into southern New England from the north late Monday or early Tuesday. This could bring another round of cooler temperatures and rain depending on how far south the front drops. Still quite early to know any further details.&& .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... Forecaster Confidence Levels... Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. 00Z TAF Update... Tonight...High confidence. Mainly VFR conditions...But can not rule out brief marginal MVFR cigs possible toward daybreak along with a brief spot shower or two. S-SW winds may gust to between 20 and 25 knots near the coast late tonight with a strengthening LLJ. We have also included LLWS for the Cape/Islands as that southwest LLJ strengthens to around 50 knots. Tomorrow...High confidence. VFR conditions dominate outside perhaps some brief marginal MVFR cigs during the early-mid morning hours. SW wind gusts of 20-30 knots develop. Generally dry weather...but a few spot showers possible mainly early in the morning and perhaps later in the day near the NH border. Strong LLWS possible over the south coast with 40-50 knots of shear to 2000 feet. Tomorrow Night...Moderate Confidence. Conditions deteriroate to MVFR tomorrow night with -RA overspreading the region from west to east. Southwest winds becoming northwest between 06 and 12Z Friday. KBOS Terminal...Moderate confidence. Increased confidence that a sea-breeze will not occur today, but there does remain a slight chance for some onshore flow between 18-20Z. KBDL Terminal...High confidence. Outlook /Friday through Monday/... Friday: Mainly VFR, with local MVFR possible. Breezy. Chance RA. Friday Night: VFR. Breezy. Slight chance SN. Saturday through Saturday Night: VFR. Sunday through Sunday Night: VFR. Breezy. Monday: VFR. Windy with local gusts up to 30 kt. && && .MARINE... Forecaster Confidence Levels... Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Tonight Through Thursday Night...High confidence. Winds increasing out of the south/southwest tonight as low- pressure passes well to the north. Moderate sustained winds between 15-25 knots with gusts up to 30 knots. Winds shift to the northwest tomorrow night as a cold front moves over the coastal waters with a round of showers. SCY criteria through the end of the week with a few gale force gusts possible on the edge of the outer marine zones. Outlook /Friday Night through Monday/... Friday: Winds less than 25 kt. Local rough seas. Chance of rain. Friday Night: Winds less than 25 kt. Seas up to 5 ft. Saturday: Winds less than 25 kt. Areas of seas approaching 5 ft. Saturday Night through Sunday Night: Winds less than 25 kt. Monday: Moderate risk for Small Craft Advisory winds with gusts up to 30 kt. Local rough seas. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...None. RI...None. MARINE...Small Craft Advisory from 8 AM Thursday to midnight EDT Thursday night for ANZ230-236. Small Craft Advisory from 5 AM Thursday to 8 AM EDT Friday for ANZ231>234-251. Small Craft Advisory from 5 AM Thursday to 5 PM EDT Friday for ANZ235-237. Small Craft Advisory from 11 PM this evening to 2 PM EDT Friday for ANZ250. Small Craft Advisory from 5 AM Thursday to 8 PM EDT Friday for ANZ254>256. && $$