Area Forecast Discussion

526 FXUS61 KBOX 151811 AFDBOX Area Forecast Discussion National Weather Service Boston/Norton MA 211 PM EDT Wed Oct 15 2025 .SYNOPSIS... Cloudy, cool, and blustery conditions today. An unseasonably cool airmass brings below normal temps and blustery conditions Thursday with ocean effect cloud cover, periods of rain showers and stronger northerly breezes across the eastern Massachusetts coast. Warming trend for Friday into the weekend before turning more unsettled as we move into early next week. && .NEAR TERM /THROUGH TONIGHT/... Key Messages * Cold and blustery overnight with near-freezing temperatures for much of southern New England Tonight Deep north/northwest flow continues to usher cool/dry air over southern New England tonight. 925 hPa temps dip to near freezing. This will support surface temperatures in the low to mid 30s across southern New England. Temperatures will be more mild near the coast in the upper 30s to low 40s...mid 40s Cape Cod. Tight pressure gradient will support steady northwest winds from 10-15 mph overnight which will yield wind chill temperatures near or below freezing for most of the region. && .SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/... Key Messages * Cooler temperatures tomorrow with continued gusty north/northwest winds * Ocean effect rain showers likely over parts of The South Shore, Cape Cod, and The Islands. Tomorrow Little change in the overall synoptic setup tomorrow, though temperatures will be much cooler as an upper-level low over northern Maine digs south/southeast past southern New England during the day tomorrow. This will place a rather robust upper-level cold pool over our area with 500 hPa temps as low as -25C over southern New England and 925 hPa temps below 0C to start Thursday. Steep lapse rates will support efficient diurnal mixing which will result in high temperatures in the low-mid 50s and also periods of 25-30 mph northwest wind gusts across southern New England. The cooler air over the relatively warmer ocean will likely result in some ocean- effect showers over Cape Cod, The Islands, and perhaps sections of The South Shore beginning tomorrow afternoon. Overall a cool/windy day. Tomorrow Night The atmosphere will likely decouple across the interior overnight, bringing an end to gusty northwest winds for most locations. However, milder temperatures near the coast may continue to support steep low-level lapse rates and enough mixing to support continued gusty northwest winds overnight, particularly over Cape Cod. Expected continued ocean effect showers over The Cape/Islands tomorrow night as well. There won`t be a whole lot of moisture to work with so we`re not anticipating any significant accumulations, but perhaps 0.1 to 0.2 inches of new rainfall by Friday morning. && .LONG TERM /FRIDAY THROUGH TUESDAY/... Key Messages... * Dry Fri/Sat/Sun with moderating temps..highs may approach 70 on Sun * Some showers possible early next week...but timing is uncertain Details... Friday/Saturday/Sunday... A mid level ridge axis approaches from the west as the upper trough shifts east of the region. This will result in continued dry weather with moderating temperatures. High temps Fri should be in the upper 50s to lower 60s with still some NW wind gusts around 20 mph. 850T warm significantly by Saturday and while we will not be able to mix that deep or fully realize at the surface...still expect highs to reach the lower to middle 60s with light winds. As the high shifts east of the region...high temps will probably reach between 65 and 70 on Sunday. Early Next Week... A vigorous shortwave trough will lift northeast across the Great Lakes early next week with an associated surface low. A cold front extending southward from the low pressure system will likely bring a period of showers to the region sometime early next week...roughly in the late Sunday night to Monday timeframe. However...there are a few ensemble members that hint at a stronger secondary low pressure system developing near or south of southern New England. If this were to occur...another period of rain would be possible sometime Tuesday into Wednesday...especially if this were to develop to our south. Whether or not this happens...appears that we will see at least one round of showers early next week in the late Sunday night into Monday timeframe. As for temperatures...they likely run a bit above normal especially in regards to overnight lows. High temps will probably top out mainly in the lower to middle 60s. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... Forecaster Confidence Levels... Low - less than 30 percent. Moderate - 30 to 60 percent. High - greater than 60 percent. 12z TAF Update: Today: Moderate Confidence Guidance has improved this morning with the exception of the lingering fog and low stratus across the South Coast & Cape. IFR/MVFR cigs improving to MVFR/VFR with the sunrise. Less certain on afternoon MVFR coverage inland to the I-95 corridor as guidance generally remains mixed. Further west, CIGS should be VFR this afternoon, but won`t rule out brief periods of MVFR with diurnal cumulus. Winds today stay NNW with gusts up to 20 knots in the afternoon. Tonight: Moderate Confidence VFR. with MVFR over the Cape and Islands. Steady northwest winds around 15 knots with 20-25 knot gusts. Tomorrow: Moderate Confidence VFR with MVFR over the Cape and Islands and periods of light showers for the East Coast. Very windy with northerly gusts of 25-30 knots inland, and 30-40 knots near the waters. KBOS Terminal...Low Confidence VFR with periods of MVFR possible through much of the day as strato cumulus form over the waters. Winds remain NNW gusting up to 20 knots today, and up to 30 knots Thursday. KBDL Terminal...Moderate Confidence MVFR this morning becoming VFR by afternoon. Gusty NNW winds up to 20 knots this afternoon and 25 knots Thursday. Outlook /Friday through Sunday/... Thursday Night: VFR. Windy with gusts up to 35 kt. Chance SHRA. Friday: VFR. Windy with gusts up to 35 kt. Friday Night through Saturday: VFR. Breezy. Saturday Night: VFR. Sunday: VFR. Breezy. && .MARINE... Forecaster Confidence Levels... Low - less than 30 percent. Medium - 30 to 60 percent. High - greater than 60 percent. Marine Through Thursday Night Gusty northwest winds will dominate the coastal waters through Friday. 20-30 knot winds overnight will gradually increase to 25-35 knots tomorrow afternoon. Seas build to 4 to 7 feet overnight and increase to 5 to 10 feet tomorrow evening. Seas will be lower off the south coast in the 3 to 5 foot range. Outlook /Friday through Sunday/... Thursday Night: Strong winds with gusts up to 35 kt. Rough seas up to 11 ft. Chance of rain showers. Friday: Low risk for gale force winds with gusts up to 35 kt. Rough seas up to 11 ft. Friday Night: Moderate risk for Small Craft Advisory winds with local gusts up to 30 kt. Areas of rough seas. Saturday: Winds less than 25 kt. Areas of rough seas. Saturday Night through Sunday: Winds less than 25 kt. Areas of seas approaching 5 ft. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...None. MA...None. RI...None. MARINE...Gale Warning from 8 AM Thursday to 8 PM EDT Friday for ANZ231- 232-250-251-254-255. Small Craft Advisory from 8 AM Thursday to 8 PM EDT Friday for ANZ233-234. Small Craft Advisory until 8 PM EDT Friday for ANZ235-237-256. && $$ SYNOPSIS...Frank/RM NEAR TERM...RM SHORT TERM...RM LONG TERM...Frank AVIATION...Frank/RM MARINE...Frank/RM NWS BOX Office Area Forecast Discussion