518
FXUS61 KBOX 011701
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
1201 PM EST Sun Nov 1 2026

.WHAT HAS CHANGED...

Increased high temperatures a few degrees above model guidance
through the middle of the week.

&&

.KEY MESSAGES...

- Dry and unseasonably mild into mid-week with highs mainly in
  the upper 60s to the lower 70s. Some spots may reach into the
  middle 70s for a day or two and challenge record highs.

- Pattern becomes more unsettled late-week into the weekend featuring
  periodic chances for rain.


&&

.DISCUSSION...

KEY MESSAGE 1...Dry and unseasonably mild into mid-week with highs
mainly in the upper 60s to the lower 70s. Some spots may reach into
the middle 70s for a day or two and challenge record highs.

An anomalous upper level ridge of high pressure will be in control
of our weather through the middle of the week. The result will be
continued dry weather with unseasonably mild temperatures. Given the
extended period of dry weather...MOS guidance is likely a few
degrees too cool during the afternoons and we have increased.
Afternoon high temperatures will mainly be in the upper 60s to the
lower 70s...although a few degrees cooler for the Cape/Islands. In
fact...925T rising into the +11C to +15C range will potentially
allow for some locations to reach the middle 70s especially towards
mid-week and challenge record high temps. The main uncertainty on
temperatures will revolve around the amount of mid-high level clouds
that spill into the region at times. Regardless...high confidence in
continued dry weather with unseasonably mild temperatures through
the middle of the week.

KEY MESSAGE 2...Pattern becomes more unsettled late-week into the
weekend featuring periodic chances for rain.

Ensemble guidance shows a consensus in a shift of the pattern late
Thursday into Friday as a mid-level trough arrives from the west.
This will advect in a plume of rich moisture 2-3 standard deviations
above normal. This will be accompanied by a frontal system that
pushes across the Ohio River Valley and into the Mid-Atlantic and
Northeast. This will likely bring us our next best shot at
precipitation. Details such as timing, rain amounts/rates are still
lower confidence due to uncertainty in the tracking of the surface
features/best forcing. If the frontal features track closer, this
could put southern New England in better forced environment and
potentially with marginal instability present. This could favor a
few rumbles of thunders or heavier downpours. Timing of this is low
confidence due to the track uncertainties, but the general timeframe
is late Thu through Sat. Lighter/spotty showers may linger at
late as Sunday. However, it likely won`t be rain for the entire
timeframe.

Ensemble guidance highlights probabilities of 30-60% for rain totals
of 0.50" or more and low probabilities (10-30%) for 1.0" or greater.
Deterministic solutions have leaned toward the upper percentile
solutions of their ensemble suite showing potential for amounts 1.0
to upward of 2.0" inches. Once guidance comes into better agreement,
confidence will increase in the exact timing of rainfall and totals.

Above normal temperatures are likely Thursday with the mid-level
thermal ridge shifting over southern New England with 925mb
temperatures +13-15C. This will support high temperatures in the
upper 60s to low/mid 70s! Temperatures likely lean seasonably warm
for Friday as well. Depending on how the system tracks, we may get
one more day of milder temperatures Saturday with more
seasonable temperatures arriving by Sunday.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...

Forecaster Confidence Levels...

Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.

18z TAF Update...High confidence.

VFR conditions will continue through the middle of the week with
just some mid-high level cloudiness at times. Winds will generally
average from the SW at 5 to 15 knots during the afternoon/s.

KBOS Terminal...High confidence in TAF.

KBDL Terminal...High confidence in TAF.

Outlook /Wednesday Night through Thursday/...

Wednesday Night: VFR.

Thursday: Mainly VFR, with local MVFR possible. Breezy. Slight
chance RA.

&&

.MARINE...

Forecaster Confidence Levels...

Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.

Tonight through Wednesday...High confidence.

An upper level ridge of high pressure will keep winds/seas below
small craft advisory thresholds through the middle of the week.
Nonetheless...we may have some SW wind gusts of 20+ knots at times
particularly nearshore during the afternoons. This may result in
some choppy seas at times...but thinking we should remain below the
need for headlines.


Outlook /Wednesday Night through Thursday/...

Wednesday night and Thursday: Seas generally less than 5 feet. Winds
less than 25 kt.


&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...None.

&&

$$

DISCUSSION...Frank/Mensch
AVIATION...Frank
MARINE...Frank/Mensch