Plainville, Massachusetts Weather Forecast Discussion

398
FXUS61 KBOX 221908
AFDBOX
Area Forecast Discussion
National Weather Service Boston/Norton MA
308 PM EDT Mon Sep 22 2025
.SYNOPSIS...
Dry weather continues until the chance for some unsettled
weather returns late tomorrow afternoon through Wednesday.
Temperatures should also average about normal this week, with
the exception of above normal temperatures Tuesday. Potential
for a more widespread rainfall event Thursday and Friday.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
Key Messages:
* Mild night with increased cloud cover.
Autumnal equinox officially arrived as of 2:19 PM, welcoming fall
with nearly picture perfect conditions. Seasonable this afternoon as
highs reach the upper 60s to lower 70s. Tonight, high pressure moves
off shore, and S/SW winds usher in higher PWATs of 1.5" and result
in increased cloud cover tonight. Temperatures lower into the middle
50s to 60F.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
Key Messages:
* Mild temperatures along with elevated humidity Tuesday. Mainly dry
  day, with showers by late afternoon to early evening into the
  overnight.
Continued S/SW flow leads to a muggy and warm first full day of fall
as the high temperatures reach the mid-70s to 80F. PWATs of 1.6"
support a muggy feel with dew points in the middle 60s.
In general much of the day is dry, shortwave energy approaches
late afternoon to early evening across western areas, providing
forcing for showers and rumbles of thunder. Conditions are not
favorable for severe thunderstorms given the late arrival (close
to sunset), the meager instability and low shear values. CAPE
is only a few hundred units and the shear is less than 20 knots,
biggest threat likely lightning and sub-severe gusts. Areas
that have the greatest chance of a storm, are across the
interior of southern New England where a few hundred units of
CAPE can be found.
Overnight the shortwave pushes east with shower activity. A mild
night ahead is expected with the S/SW flow and cloud cover. Lows
only fall to the low and middle 60s.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
Key Messages:
* Rainfall chances continue into Wednesday
* The pattern remains unsettled through the rest of this week
A low pressure traversing along a cold front will maintain rainfall
chances into Wednesday. There could be a brief lull in this rainfall
during the afternoon into the late evening hours before another low
pressure moves along this same front and increases rainfall chances
once more sometime Wednesday Night into Thursday. It appears that
rainfall chances end sometime this weekend as a cold front finally
moves across our region and we come under the influence of a high
pressure over the central Appalachians.
While it will likely not be raining the entire time from Wednesday
to Saturday morning, there is a 50-70% probability most locations
can get an inch or more of rainfall during this time. Odds are less
for 2 or more inches of rainfall, generally between 20-40%. As dry
as we have been lately, we can really use whatever rain we can get.
Temperatures should average near to slightly above normal for this
portion of the forecast.
&&
.AVIATION /19Z MONDAY THROUGH SATURDAY/...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
18Z Update:
Today...High Confidence.
VFR. Light/calm northerly winds early this morning become light
S winds today with sea breezes on the immediate coast 5-10kts.
Tonight...High Confidence.
Light SW winds expected tonight with MVFR/IFR cigs possible by
early Tuesday morning in low lying areas.
Tuesday...Moderate Confidence in ceilings/categories.
Mix of MVFR-pockets of IFR early AM. VFR/MVFR as the day goes
on and chances for TSRA/SHRA increase in the evening. SW winds
to 10 kts across the region with locally higher winds over the
Cape and Islands. Gusts up to 20 kts possible for Cape/Islands
and south coast.
KBOS Terminal...High confidence in TAF.
Sea breeze kicks out 23-00z with winds turning S.
KBDL Terminal...High confidence in TAF.
Outlook /Tuesday Night through Saturday/...
Tuesday Night: Mainly MVFR, with local IFR possible. SHRA
likely, slight chance TSRA, patchy BR.
Wednesday: MVFR/IFR conditions possible. Chance SHRA, patchy
BR.
Wednesday Night: Mainly VFR, with local IFR possible. Chance
SHRA.
Thursday: Mainly MVFR, with areas IFR possible. SHRA likely.
Thursday Night: Mainly MVFR, with areas IFR possible. SHRA
likely, slight chance TSRA.
Friday: Mainly VFR, with local MVFR possible. Chance SHRA.
Friday Night through Saturday: VFR. Chance SHRA.
&&
.MARINE...
Forecaster Confidence Levels...
Low - less than 30 percent.
Medium - 30 to 60 percent.
High - greater than 60 percent.
Through Tuesday Night...High Confidence.
High pressure south of the Maritimes leads to relatively light
winds and seas across the waters until tomorrow morning. Seas
building to 5 ft are expected over the waters tomorrow late
morning through midweek. Small Craft Advisories have been
issued for much of Tuesday into Wednesday as a precaution.
Outlook /Tuesday Night through Saturday/...
Tuesday Night: Winds less than 25 kt. Seas up to 5 ft. Chance
of rain showers, slight chance of thunderstorms, patchy fog.
Wednesday: Winds less than 25 kt. Seas up to 5 ft. Chance of
rain showers, patchy fog.
Wednesday Night: Winds less than 25 kt. Seas up to 5 ft. Chance
of rain showers.
Thursday: Winds less than 25 kt. Seas locally approaching 5 ft.
Rain showers likely.
Thursday Night: Winds less than 25 kt. Seas locally approaching
5 ft. Rain showers likely, slight chance of thunderstorms.
Friday: Winds less than 25 kt. Seas locally approaching 5 ft.
Chance of rain showers.
Friday Night through Saturday: Winds less than 25 kt. Chance of
rain showers.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory from noon Tuesday to 2 AM EDT Wednesday
     for ANZ235-237.
     Small Craft Advisory from 2 AM Tuesday to 8 PM EDT Wednesday
     for ANZ250.
     Small Craft Advisory from 2 AM Tuesday to 8 AM EDT Wednesday
     for ANZ254>256.
&&
$$
SYNOPSIS...Belk/Dooley
NEAR TERM...Dooley
SHORT TERM...Dooley
LONG TERM...Belk
AVIATION...Belk/KP
MARINE...Belk/Dooley

NWS BOX Office Area Forecast Discussion