-- Discussion containing changed information from previous version are highlighted. --
380
FXUS61 KBOX 272310
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
710 PM EDT Thu Mar 27 2025

.SYNOPSIS...
Dry and pleasant weather is on tap for Friday with a slight
risk for a localized spot rain/snow shower tonight. Periods of
unsettled weather are on tap Friday night through this weekend
with a backdoor cold front in the vicinity of southern New
England. We are favoring most of our region being on the chilly
side of this boundary, except for Saturday when areas near and
especially southwest of a Springfield to Providence line may
stay on the warm side, resulting in a 30-40 degree temperature
spread across our region. Much of the region may finally warm up
by Monday with another round of showers associated with an
approaching cold front. Drier weather returns Tuesday and
Wednesday as high pressure builds into the region with
temperatures on the cool side.

&&

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

* Gusty through sunset with near normal temperatures.

* Mostly dry night, low chance for an isolated rain or snow
  shower.

Diurnal clouds blossomed over the eastern half of southern New
England. These clouds should dissipate towards sunset. Some
echoes on the radar, but no evidence of it reaching the ground.
Based on the range from the radar, thinking these are water
droplets within the cloud layer itself. gusty winds should also
diminish towards sunset.

After a brief period of clearing, more clouds should arrive from
the SW late tonight as a warm front works its way through.
Expecting slightly above normal low temperatures. Thinking most
of our region remains dry, but cannot completely dismiss the
idea of a spot rain or snow shower.

&&

.SHORT TERM /FRIDAY NIGHT/...
Key Messages:

* Friday is mild and cloudy, but dry.

Another breezy day anticipated, but this time from the
southwest. This should lead to above normal high temperatures.
Despite some clouds, much of the day should remain dry until
just ahead of an approaching cold front late in the day. Even
then, the greatest risk for showers should remain west of the
Connecticut River.

A slightly different story Friday night, when the cold front
associated with a low pressure over eastern Canada collides with
a warm front associated with a low pressure over the northern
plains. This should lead to a nearly stationary boundary late
Friday night. We do not yet have a lot of confidence in the
location of this front, but it is most likely going to keep most
of southern New England on the colder side, which will be more
noticeable Saturday.

Looking at some rainfall Friday night, especially after
midnight.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
Key Messages:

* Still high uncertainty in exact placement, but backdoor cold
  front Sat will result in a potential 30-40 degree temperature
  spread in SNE with highs 30s/40s N of CEF-PVD line and
  60s/70s S of this front

* Showers likely across northern MA Sat, with a low risk for
  spotty light FZRA/FZDZ in Berks/Worcester Hills

* Potentially turning much milder Mon with more showers possible
* Dry weather returns Tue into Wed with highs mainly in the 40s
  to the lower 50s

Details...

Saturday & Sunday...

Weekend forecast continues to be quite tricky. High pressure
over the James Bay coupled with low clouds north of the frontal
boundary will allow shallow cold air to dip southward into
southern New England. Still a large spread in the guidance as to
where exactly the boundary will set up, but leaning more towards
NAM12KM solution at this time. Appears areas roughly southwest
of a CEF-PVD line may be in the warm sector and see highs reach
into the 60s and 70s while areas north of the boundary will
remain in the high 30s and low 40s.

This boundary could shift further north or south depending on
several meteorological processes. Given the shallow nature of
the cold air usually best to favor a greater potential for the
front to shift further south as opposed to north. That being
said, there is the potential for a 30-40 degree temp spread on
Sat from HFD to FIT/LWM.

It does appear that later Sat the backdoor cold front will sag
further southwest behind a wave of low pressure. Therefore,
thinking by Sun our entire region may be on the chilly side of
the boundary with highs mainly in the upper 30s & 40s.

As for precipitation chances... the threat for some showers will
linger this weekend, but much of these may end up in northern MA
where better forcing will reside. And even in this region, not
expecting the entire period to be a washout. Still can`t rule
out a brief period of light freezing rain/freezing drizzle in
the northern Worcester Hills this weekend; however, this will
depend upon on how much shallow cold air will be pushed
southward from Quebec and northern New England.

Monday...

The next wave of low pressure will be lifting northeast across
the Great Lakes allowing a cold front to approach from the west.
As this happens, much of the region will likely be in the warm
sector ahead of the approaching cold front. This will allow
highs to reach the 60s. We do expect another round of showers
ahead and along the approaching cold front sometime Mon into Mon
night.

Tuesday and Wednesday...

Drier weather returns into southern New England Tue into Wed
behind the cold front. Highs both days should be in the 40s to
the lower 50s with Wed likely being the cooler of the days.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.

00Z Update...

Tonight...High Confidence.

VFR. Winds turning SW with 20 knot gusts developing overnight.

Friday...High Confidence.

VFR. W winds 8-14 knots with some 20+ knot gusts possible.

Friday Night...Moderate Confidence.

VFR to start, then trending to MVFR/IFR after midnight.

BOS TAF...High confidence in TAF.

BDL TAF...High confidence in TAF.

Outlook /Saturday through Tuesday/...

Saturday: Mainly VFR, with local IFR possible. Breezy. Chance
RA, chance FZRA.

Saturday Night: MVFR/IFR conditions possible. Chance RA, chance
FZRA.

Sunday: Mainly VFR, with areas IFR possible. Chance RA, chance
FZRA.

Sunday Night through Monday: MVFR/IFR conditions possible.
Breezy. Chance RA.

Monday Night: Mainly VFR, with areas MVFR possible. Breezy. RA
likely.

Tuesday: VFR. Breezy.
-- End Changed Discussion --

&&

.MARINE...
Forecaster Confidence Levels:

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

Through Friday night: High Confidence.

High pressure well south of the waters tonight shifts slightly
farther offshore for Friday. An approaching cold front stalls
somewhere across the waters Friday night. Small Craft
Advisories continue for marginal gusts 25-30 kt with 5 foot
seas towards the waters SE of Nantucket. May need to expand the
advisory if more sunshine breaks out than currently expected
Friday and deeper mixing develops.

Outlook /Saturday through Tuesday/...

Saturday: Winds less than 25 kt. Local rough seas. Slight
chance of rain.

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

Sunday: Winds less than 25 kt. Seas up to 5 ft. Chance of rain.

Sunday Night: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Seas up to 5 ft. Chance of rain.

Monday: Moderate risk for Small Craft Advisory winds with gusts
up to 25 kt. Areas of rough seas. Chance of rain.

Monday Night: Moderate risk for Small Craft Advisory winds with
gusts up to 25 kt. Rough seas up to 9 ft. Rain likely.

Tuesday: Winds less than 25 kt. Rough seas up to 9 ft. Slight
chance of rain.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory from 5 AM to 2 PM EDT Friday for
     ANZ231>235-237-251.
     Small Craft Advisory from 2 AM to 2 PM EDT Friday for ANZ250-
     254.
     Small Craft Advisory until 4 PM EDT Friday for ANZ255-256.

&&

$$

SYNOPSIS...Belk/McMinn
NEAR TERM...Belk
SHORT TERM...Belk
LONG TERM...McMinn
AVIATION...Belk/McMinn
MARINE...Belk/McMinn