Area Forecast Discussion
National Weather Service Boston/Norton MA
205 AM EDT Sat Oct 24 2026
.WHAT HAS CHANGED...
No meaningful changes to the forecast, with an extended stretch of
quiet and dry weather ahead.
.KEY MESSAGES...
- Prolonged stretch of dry weather across southern New England.
Moderating afternoon temperatures this weekend, though chilly
mornings will bring widespread frost away from the immediate
coast.
.DISCUSSION...
KEY MESSAGE 1...Prolonged stretch of dry weather across southern New
England. Moderating afternoon temperatures this weekend, though
chilly mornings will bring widespread frost away from the immediate
coast.
If the forecast discussion starts sounding like a broken record over
the next several days, you can thank strong high pressure for that!
An extended stretch of dry weather is expected, with some day-to-day
variability in temperatures, but otherwise not much excitement on
the horizon. In fact, global ensembles paint a rather parched
picture for southern New England, with cumulative probabilities of
measurable precipitation (0.01 inches or greater) generally less
than 10 percent through much of next week.
An expansive area of surface high pressure, around 1035 mb, remains
anchored across the region this weekend, with some guidance
suggesting pressures could approach 1040 mb Saturday night. This
will promote plenty of sunshine, light winds, and generally quiet
conditions. Temperatures at 925 mb warm to +6C to +9C this
afternoon, supporting highs in the upper 50s to lower 60s. If this
were a few weeks earlier, with a higher sun angle, we'd likely be
talking about highs in the middle to upper 60s. But here we are,
nearing the end of October! Temperatures aloft continue to moderate
Sunday and Monday, with 925 mb temperatures approaching +10C Sunday
and +13C Monday. This should support highs in the lower to middle
60s Sunday, with some locations potentially reaching 70F Monday.
Overnight temperatures, however, are a different story. Clear skies
and light to calm winds beneath strong high pressure will promote
efficient radiational cooling. Opted to trend overnight lows below
NBM guidance, which typically runs too warm in these setups.
Saturday and Sunday mornings, and to some extent Monday morning,
will be quite cold, with lows in the 20s to lower 30s and widespread
frost away from the immediate coast and urban heat islands. Be sure
to protect those mums and Halloween pumpkins! One interesting
feature of this setup will be the potential for significant
temperature differences between sheltered valleys and higher
elevations. With clear skies and light winds promoting strong
radiational cooling, colder air will settle into the valleys, while
some elevated locations may remain several degrees warmer within the
nocturnal temperature inversion.
Looking ahead, a moisture-starved cold front approaches from the
north-northwest late Monday night into early Tuesday. However,
persistent high pressure and dry air will likely limit the front to
little more than some additional cloud cover and a cooler air mass.
Highs return to the 50s Tuesday and Wednesday before potentially
rebounding into the 60s Thursday and Friday. Overnight temperatures
should trend closer to seasonable levels, although confidence is
lower given uncertainty surrounding cloud cover and winds, both of
which could limit radiational cooling. Fingers crossed this dry
pattern holds just a little longer and gives us a dry All Hallows'
Eve!
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
06Z TAF Update:
Today through Sunday...High confidence in flight categories,
moderate confidence in wind direction and speed.
High pressure brings dry weather and clear skies, with VFR
conditions prevailing through the period. Wind direction and speed
are a bit more challenging given the weakly forced environment.
Winds around 2 kft are generally NW to N near 10 kt, though daytime
heating and temperature differences between land and water may allow
a weak sea breeze to develop along the coast. Confidence in sea-
breeze development remains low. Regardless of direction, surface
winds should remain light, generally 4 to 8 kt. Tonight, winds
become calm to light and variable, generally less than 3 kt. More of
the same is expected Sunday, with winds around 2 kft shifting to the
west at 5 to 10 kt, while surface winds remain light, generally 4 to
8 kt.
KBOS Terminal...High confidence in flight categories, moderate
confidence in prevailing winds, but low confidence in sea-breeze
development.
VFR. Prevailing NW to NNW winds of 4 to 8 kt. High-resolution
guidance suggests a weak sea breeze may develop 17Z to 21Z, shifting
winds to ESE around 5 kt. Confidence remains low, so opted to
include a PROB30 group to account for this possibility.
KBDL Terminal...High confidence in flight categories, moderate
confidence in wind direction and speed.
VFR. Light winds generally less than 5 kt, with variable directions.
Outlook /Monday through Wednesday/...
Monday: VFR.
Monday Night through Tuesday: VFR. Breezy.
Tuesday Night through Wednesday: VFR.
.MARINE...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
Through Sunday...High confidence.
High pressure remains in control, bringing dry weather and generally
favorable marine conditions for the next several days. Today, winds
will be light and generally from the northwest, with gusts at most 8
to 12 kt, becoming light WSW on Sunday. Despite the lighter winds,
seas across the outer waters remain elevated at 4 to 6 ft,
warranting a continuation of Small Craft Advisories through this
evening for seas rather than winds. Seas subside below 4 ft by
Sunday.
Outlook /Monday through Wednesday/...
Monday: Winds less than 25 kt.
Monday Night: Winds less than 25 kt. Seas locally approaching
5 ft.
Tuesday: Low risk for Small Craft Advisory winds with gusts up
to 20 kt. Seas up to 5 ft.
Tuesday Night: Winds less than 25 kt. Seas up to 5 ft.
Wednesday: Winds less than 25 kt. Areas of seas approaching
5 ft.
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory until 8 PM EDT this evening for ANZ250.
Small Craft Advisory until 6 AM EDT Sunday for ANZ254-255.
Dooley