AFDBOX Area Forecast Discussion National Weather Service Boston/Norton MA 720 PM EDT Thu Mar 26 2026 .WHAT HAS CHANGED... Increased this afternoon high temps to upper 60s/low 70s away from the south coast, given recent hourly trends coupled with strong WAA and March sun. && .KEY MESSAGES... - Warm conditions today will be followed by widespread showers tonight into early Friday morning. Cooler Fri, but still near normal, along with increasing filtered afternoon sunshine. - Colder than normal and blustery Saturday, then not as cold Sunday with gradual warming into early next week. Trending unsettled with periods of showers Tuesday through late-week. && .DISCUSSION... KEY MESSAGE 1...Warm conditions today will be followed by widespread showers tonight into early Friday morning. Cooler Fri, but still near normal, along with increasing filtered afternoon sunshine. Given rapidly warming temps late this morning and early afternoon, bumped up highs away from the south coast. Model soundings have +11C/+12C at 950 mb along with good mixing via SW winds 15-25 mph, should support highs in the upper 60s to lower 70s. Cooler south coast given SSW wind trajectory. Short wave and attending cold front approach the region this evening from the west. Good model agreement on showers arriving in CT and western MA between 6PM-9PM and 9PM-12AM. Some elevated instability that may yield an isolated thunderstorm tonight, along with a few downpours, but overall, mainly just widespread showers. Modest forcing for ascent coupled with a saturated column, will yield a swath of QPF of 0.2 to 0.4 inches, with local amounts up to 0.5 to 0.6 inches across western CT/MA. By no means any flooding, more like beneficial rains. Above average temps tonight give prefrontal airmass. Lows 40-45, mid to upper 30s across northern MA. These temps are about 5-10 degs above normal. Friday...any morning showers exit off the south coast by midday, with drier and cooler post frontal airmass overspreading the region from north to south. This will support increasing sunshine through mid/high clouds. However, strong CAA on gusty N-NW winds 15-25 mph, with gusts up to 30 mph during the morning, will yield much cooler temps with highs 45-50. These temps are seasonable for late March, but the gusty NNW wind will make it feel much cooler. KEY MESSAGE 2...Colder than normal and blustery Saturday, then not as cold Sunday with gradual warming into early next week. Trending unsettled with periods of showers Tuesday through late-week. Dry, cool, and windy conditions expected Saturday. Under mid-level troughiness, a below normal airmass sits over the northeast. 925mb temperatures stay around -8 to -6C yielding highs in the mid to upper 30s, around 10-15 degrees below normal for late March. CAA will support a well-mixed boundary layer bringing down stronger NW winds with gusts 20-30 mph. This will make it feel much like Winter on Saturday with wind chill values in the 20s. Temperatures gradually moderate Sunday as the mid-level trough exits to the east. High temperatures return to seasonable values in the 40s to near 50. Another windy day is possible Sunday with a SW LLJ jet nudging in from the south bringing gusty SW winds 20-35 mph. After a few dry days, the pattern trends unsettled with ensemble guidance showing a series of shortwave troughs moving through the flow, tracking across southern New England. There is some subtle differences in timing across guidance in the timing of the waves that will need to be ironed out as we get closer. With anomalous moisture gradually advecting in early to mid-week, this will support periods of showers through the week. Temperatures lean above normal next week. && .AVIATION /00Z FRIDAY THROUGH TUESDAY/... Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Overnight...Moderate confidence. Strengthening low level jet will increase south westerly wind shear to around 60KTS from about 00z-06z, strongest LLWS along the south coast of RI/MA, including Cape Cod and the Islands. Will also have to contend with IFR conditions and -RA from 00z to around 12z Friday as a cold front works its way southeast. Friday...moderate confidence. MVFR/IFR conditions early Friday especially along the S coast. Quick improvments to VFR expected from NW to SE after 12z. Improvements may take as long as 18z for the Cape and Islands. Southwest winds becoming northwest by Friday associated with the FROPA. Friday night...High confidence. VFR cloud bases along with dry weather and modest NNE winds. KBOS Terminal...High confidence in trends. Moderate confidence in exact timing. KBDL Terminal...High confidence in trends. Moderate confidence in exact timing. Outlook /Friday Night through Tuesday/... Saturday: Mainly VFR, with local MVFR possible. Breezy. Saturday Night: VFR. Sunday: VFR. Breezy. Sunday Night through Monday: Breezy. Monday Night: Breezy. Slight chance RA. Tuesday: Breezy. Chance RA. && .MARINE... Forecaster Confidence Levels... Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. Through Friday night...High confidence. SSW winds sustained winds between 15-25 kt with gusts up to 30 kt this evening. Winds shift to the northwest 06z-12z Fri, as a cold front moves over the coastal waters with a round of showers. North to northeast winds expected for Friday. Small Craft Advisory criteria through the end of this week with a few gale force gusts possible on the edge of the outer marine zones. Outlook /Friday Night through Tuesday/... Saturday: Winds less than 25 kt. Areas of seas approaching 5 ft. Saturday Night: Winds less than 25 kt. Sunday through Sunday Night: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Seas locally approaching 5 ft. Monday: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Areas of rough seas. Monday Night: Low risk for Small Craft Advisory winds with gusts up to 25 kt. Areas of rough seas. Slight chance of rain. Tuesday: Winds less than 25 kt. Local rough seas. Chance of rain. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...None. RI...None. MARINE...Small Craft Advisory until midnight EDT tonight for ANZ230-236. Small Craft Advisory until 8 AM EDT Friday for ANZ231>234-251. Small Craft Advisory until 5 PM EDT Friday for ANZ235-237. Small Craft Advisory until 2 PM EDT Friday for ANZ250. Small Craft Advisory until 8 PM EDT Friday for ANZ254>256. && $$