Sunderland, Massachusetts Weather Forecast Discussion

478
FXUS61 KBOX 161957
AFDBOX
Area Forecast Discussion
National Weather Service Boston/Norton MA
357 PM EDT Tue Sep 16 2025
.SYNOPSIS...
Dry weather with temperatures near or just warmer than average
through mid week. A low chance for showers for coastal parts of
southern New England Wednesday night into Thursday morning as a
low passes offshore. More autumn-like temperatures possible for
this weekend following a cold front, then a warming trend early
next week.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
Key Messages:
* Quiet weather overnight with seasonable temperatures
Very little change in the synoptic pattern tonight, thus the quiet
weather will persist. An area of surface high pressure centered over
northern New England will gradually shift east over The Gulf of Maine
overnight. This will continue to support onshore flow out of the
east/southeast over southern New England. As temperatures cool
overnight, we should see a return of low-stratus and possibly some
patchy fog across eastern MA. Expect similar low temperatures to
last night in the upper 40s to low 50s.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
Key Messages
*  Mix of sun and clouds again Wednesday with highs in the low 70s
*  Shower chances increasing tomorrow evening into tomorrow night as
   low-pressure approaches southern New England from the south
Wednesday
High pressure to our east and ridging aloft continue to suppress the
northward movement of a low-pressure system off the Mid-Atlantic
Coast for much of the day tomorrow. Conditions on Wednesday will be
similar to Tuesday with some low clouds and fog early transitioning
to partly sunny skies by late morning/early afternoon. As low-
pressure to the south slowly advances north/northeast, there will be
increasing chances for a few isolated to scattered showers showers,
mainly along the south coast. Nonetheless, expect most of tomorrow
to be dry.
Wednesday Night
Low pressure to our south finally lifts east/northeast bringing a
period of showers to at least the southeastern half of southern New
England. Some uncertainty with respect to how far inland showers
progress, but latest guidance suggests that southeast MA, The Cape,
and Islands will have the greatest likelihood of observing
appreciable rainfall. Cloud cover and higher dewpoints will keep
temperatures mild in the mid to upper 50s Wednesday night.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
Key Messages:
* A few showers possible Thu morning, otherwise warm and dry Thu &
  Fri
* Dry and cooler this weekend followed by a warming trend early next
  week
Weakening low pres south of New Eng moves offshore Thu, but may
bring a few lingering showers near the south coast in the morning.
Otherwise, it looks mostly dry and seasonably warm Thu. Warm and dry
weather continues into Fri as a dry cold sweeps through during the
afternoon. Stronger cold advection lags well to the north of the
front on Fri which will allow temps to reach well into the 70s and
possibly near 80 across CT/RI and SE MA. Then turning much cooler
Fri night as cooler settles southward with lows dropping into the
40s and possibly some upper 30s in NW MA.
Cooler airmass during the weekend as high pres builds in from the
north. Highs Sat will be in the 60s to near 70 with slight warming
on Sunday as high pres moves to the east. While it will be quite
dry, winds will not be that gusty which will mitigate any fire
weather concerns. Chilly night Sat night as good radiational cooling
with high pres overhead. Lows will drop into the 40s with some upper
30s in the colder radiators.
Then a warming trend is expected next week with temps possibly
warming into the 80s away from the coast by next Tue. EPS and
GEFS ensembles showing increasing probs of 80+ on Tue.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
Through 00Z...High confidence.
VFR. Light east/northeast winds.
Tonight...High Confidence.
Mainly VFR with IFR/MVFR at ORH/BED. Lower ceilings/vsbys at BOS
are uncertain as the inland extent of lower ceilings and vsbys
across eastern MA is uncertain. Included a TEMPO group from
08-12Z for IFR cigs and MVFR vsbys to encompass the most likely
time of lower ceilings at BOS. Elsewhere VFR with light easterly
winds.
Wednesday...High confidence.
Generally VFR with patches of MVFR in SHRA along the south
coast, especially the Cape and Islands. Winds E up to 10 kts.
Wednesday Night...High Confidence
Mainly MVFR ceilings with -SHRA. Light easterly winds.
KBOS Terminal...Moderate confidence in TAF
Fog bank over Boston Harbor may result in a brief period of
lower vsbys this afternoon. Also a chance for more fog/low
ceilings early tomorrow, but confidence is moderate as most
forecast guidances keeps this weather inland.
BDL Terminal...High confidence in TAF.
Outlook /Thursday through Sunday/...
Thursday: VFR. Slight chance SHRA.
Thursday Night: Mainly VFR, with local IFR possible. Patchy FG.
Friday: VFR. Widespread FG.
Friday Night: VFR. Breezy. Patchy FG.
Saturday: VFR. Breezy.
Saturday Night: Mainly VFR, with local IFR possible. Widespread
FG.
Sunday: VFR. Breezy. Widespread FG.
&&
.MARINE...
Forecaster Confidence Levels...
Low - less than 30 percent.
Medium - 30 to 60 percent.
High - greater than 60 percent.
Through Wednesday night...High confidence.
Small Craft Advisory remains in effect through 00z Thursday.
Elsewhere, seas are expected to remain below 5 ft through the at
least Wednesday night.
Winds expected to remain light over the eastern waters and
remain generally around 15 kts over the southern waters. Gusts
to 20 kts are possible, but should remain infrequent.
Outlook /Thursday through Sunday/...
Thursday: Winds less than 25 kt. Chance of rain showers. Local
visibility 1 to 3 nm.
Thursday Night: Winds less than 25 kt. Patchy fog. Local
visibility 1 to 3 nm.
Friday: Winds less than 25 kt. Patchy fog. Local visibility
1 nm or less.
Friday Night: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Areas of seas approaching 5 ft. Patchy fog.
Saturday: Winds less than 25 kt. Areas of seas approaching
5 ft.
Saturday Night: Winds less than 25 kt. Patchy fog.
Sunday: Winds less than 25 kt.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory until 8 PM EDT Wednesday for ANZ256.
&&
$$
SYNOPSIS...KJC/RM
NEAR TERM...RM
SHORT TERM...RM
LONG TERM...KJC
AVIATION...KJC/RM
MARINE...KJC/RM

NWS BOX Office Area Forecast Discussion