Newton, Massachusetts 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

735
FXUS61 KBOX 281701
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
101 PM EDT Wed May 28 2025

.SYNOPSIS...
Showers arrive late tonight into Thursday as weak low pressure
passes offshore. Another round of showers is expected for the first
part of the weekend as a stronger low pressure center tracks through
New England. Cooler and dry weather follows Sunday into Monday, then
a warming trend should take place next week.

&&

.NEAR TERM /THROUGH THURSDAY/...
Key Messages:

 * Showers arrive overnight

 * Cooler Thu with showers focused in RI and eastern MA

Showers were making slow progress toward SNE this afternoon and
will fight against surface ridging and dry air in place across
region. Eventually column will moisten up as ridge moves
offshore which will allow showers to affect most of SNE
overnight through sunrise Thu.

Overall this system is not very impressive with either moisture
and dynamics, but weak surface low tracking across Cape Cod
later in day Thu will help focus most of showers Thu across RI
and eastern MA, where we have some collocation of theta-e axis
and nose of 850 LLJ, though we also can`t rule out a few
showers farther to west or even some drizzle as what lift there
is exits offshore.

&&

.SHORT TERM /THURSDAY NIGHT/...
Key Message:

 * Remaining cloudy, perhaps a spot shower.

Plenty of low level moisture lingers Thu night so clouds should
remain locked in, especially with broad W/SW flow aloft and a
weak surface trough moving through. There may be enough weak
lift to support a brief shower or even patchy drizzle.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Key Messages:

 * Widespread rain Fri night into Sat but no flooding expected.

 * Cooler/drier weather follows, then a warming trend next week.

Another weekend, another cutoff low. This time core of upper low
remains to our north but allows surface low to track through New
England and tap into plenty of moisture to result in a widespread
rainfall in Fri night to Sat morning timeframe. Although moisture
advection looks fairly impressive with PWATs climbing to over 1.5"
per model guidance, this does not look to have a setup for excessive
or flooding rainfall, more like rainfall totals in 1/2 to 1" range.
Certainly appears that stronger dynamics will be focused to
north in this case.

Upper trough/closed low meanders around southern Canada and Gulf of
Maine early next week keeping SNE in a dry but somewhat cooler
pattern (although not too far from average). We then see a split in
guidance toward middle of next week as one camp keeps upper low
meandering near Maritimes and results in a dry but somewhat cooler
pattern, while other camp ejects upper low out to sea and allows
stronger upper ridging to build into region. This latter camp
results in a much warmer pattern taking shape with potential for
some first 90-degree readings of season by middle of next week.
However, uncertainty remains very high at this point and our
forecast will reflect more of an average between these two
solutions.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.

18z TAF Update: High confidence.

VFR with S/SW winds through early tonight. Ceilings lower to
MVFR overnight in scattered -SHRA as winds back to E/SE, then
to IFR Thu with E/NE winds 10-15kt. Some improvement possible Thu
night but MVFR/IFR ceilings should persist.

BOS TAF...High confidence in TAF.

BDL TAF...High confidence in TAF.

Outlook /Friday through Monday/...

Friday: Mainly VFR, with local IFR possible. Slight chance
SHRA, patchy FG.

Friday Night: Mainly IFR, with local MVFR possible. SHRA
likely, slight chance TSRA, patchy FG.

Saturday: MVFR/IFR conditions possible. Breezy. SHRA likely,
slight chance TSRA, patchy FG.

Saturday Night: Mainly VFR, with local MVFR possible. Breezy.
Chance SHRA.

Sunday: VFR. Breezy. Slight chance SHRA.

Sunday Night through Monday: VFR.

&&

.MARINE...
Forecaster Confidence Levels:

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

Overall high confidence through the weekend.

Expanded the SCA for seas on south coastal waters as weak low
pressure brings marginal 5-6 ft seas, mainly on open waters,
starting late tonight and lingering into Thu night.

Otherwise some 20kt gusts will persist around Cape Cod through
early this evening before winds diminish. Weak low passing near
Cape Cod and Islands late Thu will bring showers overnight into
Thu but winds stay below 15kt.

Outlook /Friday through Monday/...

Friday: Winds less than 25 kt. Areas of seas approaching 5 ft.
Slight chance of rain showers, patchy fog. Local visibility
1 nm or less.

Friday Night: Winds less than 25 kt. Seas locally approaching
5 ft. Rain showers likely, slight chance of thunderstorms,
patchy fog. Visibility 1 nm or less.

Saturday: Winds less than 25 kt. Local rough seas. Chance of
rain showers, slight chance of thunderstorms, patchy fog. Local
visibility 1 nm or less.

Saturday Night: Winds less than 25 kt. Areas of rough seas.
Chance of rain showers.

Sunday: Winds less than 25 kt. Local rough seas.

Sunday Night: Winds less than 25 kt. Areas of seas approaching
5 ft.

Monday: Winds less than 25 kt. Seas locally approaching 5 ft.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory from 4 PM Thursday to 2 AM EDT Friday for
     ANZ235-237.
     Small Craft Advisory from 11 AM Thursday to 6 AM EDT Friday
     for ANZ254>256.

&&

$$

JWD