Area Forecast Discussion
Issued by NWS Boston, MA

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FXUS61 KBOX 250528
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
128 AM EDT Mon Mar 25 2024

.SYNOPSIS...
Dry Monday but windy along the coast, especially Cape and
Islands. Unsettled weather pattern for Tuesday through Friday.
Periods of light rain showers for eastern New England on
Tuesday, then widespread light showers for Wednesday. A better
chance at widespread steadier rains may then develop Thursday
and Friday as coastal low pressure moves closer to Southern New
England. Turning blustery and drier for Saturday.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
Updated: 10:15pm

No wholesale changes during this update, did massage sky grids
across eastern Massachusetts. There are a blanket of clouds, but
those are high/cirrus clouds, giving off a milky look with the
nearly full moon.

Latest forecast from the NERFC came in just before 10pm and did
update the current warnings/reissued. Current warnings continue
for Taunton River at Bridgewater, Pawtuxet River at Cranston,
Pawcatuck River at Westerly, and Wood River at Hope Valley.

Two rivers that we continue to watch for the potential to reach
minor flood stage are Pawcatuck River at Rood River Junction by
late Monday morning, though the current forecast is having the
river crest at minor flood - will hold off on a river flood
warning until early morning guidance comes in. In collab with
the NERFC was told the forecast has been decreasing throughout
the day, stay tuned! Lastly, the Charles River at Dover may
crest into minor flood by Tuesday afternoon/late evening.


715 PM Update:

Boosted sky cover a bit for the second half of the night across
central and eastern MA, eastern CT and RI but this will be just
an increasing cirrus canopy. Otherwise no other significant
change needed to the going forecast.

Pretty tranquil evening so far for most of SNE; however
tightening NE pressure gradient over southeast New England is
leading to NE breezes around 25-35 mph. As we move through the
night, will see increasing NE winds spread northwestward. Until
then, strong radiational cooling is likely especially over NW MA
given a fresh if light snowpack. Increasing cirrus clouds will
also spread landward, but the greatest concentration of those
high clouds will be further east one goes.

Coldest lows across NW and northern MA with readings in the
upper teens to low 20s; low temps to be steadily warmer the
further SE one goes and there may be little if any appreciable
decrease in temps overnight across SE MA, Cape and Islands with
the overcast cirrus canopy and the increasing onshore breezes.

Previous discussion:

Fortunately for those in eastern MA/RI clouds have cleared this
afternoon, though if you`re on Cape Cod you remain stuck under
stubborn high clouds. This moisture sticks around tonight as do
these gusty winds thanks to our proximity to a low well east of the
Carolinas. This will keep winds gusting 30 to 40 mph along the coast
(especially southeast MA) tonight with seas 10-12 ft. Lows dip into
the teens in the high terrain of western/northern MA but will be
closer to freezing for coastal locations in a well mixed boundary
layer.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TUESDAY/...
Monday stays dry as that coastal low well to our south sits nearly
stationary or retrogrades in response to a broad high pressure
center over Nova Scotia. This keeps winds gusty on Monday, gusting
30-40 mph again (strongest along the coast). The only location that
stands the chance of seeing some rain Monday night will be Cape Cod
as some guidance brings the low close enough for peripheral moisture
to move onshore from the east in the form of light rain showers.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
Highlights:

* Overcast with onshore breezes and periods of light rain showers
  Tue with best chances at light showers eastern half of Southern
  New England. Temps cooler than normal.

* Milder Wed but with showers at times.

* Unsettled Thurs and Fri with rain showers brought by a stalling
  front and low pressure moving on it.

* Dry and blustery Sat.

Details:

Overall a pretty unsettled pattern through the rest of the workweek,
with several chances at clouds and at least light showers. Greater
rain chances develop later in the week although the exact details
are still a bit unclear.

Tuesday and Wednesday:

Distant coastal low pressure still expected to bring an enhanced
onshore flow and spread a blanket of low clouds and light showers on
Tue, especially for central and eastern sections of SNE. Coastal
breezes with NE/E wind gusts around 25-30 mph. Leftover though
weakening sfc ridge axis over western MA and portions of CT should
supply enough subsidence to limit chances for light showers. Better
chances for widespread lighter showers takes place Tue night and
especially into Wed as this moisture interacts with a slow-moving
frontal system. Still, QPF amts are on the light side. Considerable
cloudiness, periods of rain and shallow mixing supports highs in the
mid to upper 40s on Tue, and in the upper 40s to lower/mid 50s for
Wed.

Thursday through Friday Night:

Frontal boundary then stalls near SNE or just offshore, and
continued moisture acting on this frontal boundary to focus
additional rain chances into Thurs. There is indication later Thurs
and continuing into Fri that vort energy coming out of the
southeastern states will enhance rain chances. Carried high chance
to low likely PoP starting late Thurs into Fri. What is less agreed
upon is the location and track of an area of low pressure around the
Carolinas with varied depictions in the global models on its how
strong it develops and where it tracks. That would influence how
much rain we do see and when will rain shift offshore. GFS and ECMWF
have similar depictions, with low pressure well offshore Fri and Fri
night and rain chances ending by Fri night. The Canadian GEM has a
considerably stronger low that is also closer to New England and
would bring greater impacts in terms of both rain and winds, but
looking at ensembles, it seems to be more of an outlier outcome at
this point.

Saturday:

High pressure develops into Sat leading to dry weather. However
pocket of colder air aloft and a pretty tight NW gradient flow could
favor a blustery day.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
Forecast Confidence Levels:

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

06z TAF Update:

Today and Tonight... High Confidence.

VFR. Eastern terminals have NE wind 15 to 20 knots with gusts to
30 knots. Western terminals have NE wind 10 to 15 knots and
gusts to 25 knots.

Tuesday... High Confidence.

VFR, with MVFR ceilings approaching from southeast to northwest
shortly after 12z and then trending MVFR with isolated areas of
IFR after 18z. Low chance for an isolated light rain shower for
eastern terminals. Eastern terminals have NE wind 15 to 20
knots with gusts to 30 knots. Western terminals have NE wind 10
to 15 knots and gusts to 25 knots.

KBOS TAF...High confidence in TAF.

KBDL TAF...High confidence in TAF.

Outlook /Tuesday Night through Friday/...

Tuesday: Mainly VFR, with areas IFR possible. Windy with gusts
up to 35 kt. Chance RA, slight chance FZRA.

Tuesday Night: Mainly IFR, with areas VFR possible. Breezy.
Chance RA, chance FZRA.

Wednesday: Mainly VFR, with areas IFR possible. Chance RA.

Wednesday Night: Mainly VFR, with local IFR possible. Chance
RA.

Thursday: MVFR/IFR conditions possible. Chance RA.

Thursday Night: MVFR/IFR conditions possible. Breezy. RA
likely.

Friday: Mainly VFR, with local MVFR possible. Windy with gusts
up to 30 kt. Chance RA.

&&

.MARINE...
Forecaster Confidence Levels:

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

Tonight: Low pressure developing to the south will increase gusts
and seas. NE winds 20-35 kts gusting 35 to 40 kts with seas
increasing to 12-14 ft.

Monday: Low pressure system moves north and continues gusty NE gales
on the southern and eastern outer waters. Northeast waters gusts
near 30 knots. Seas on the outer waters are greater than 14 feet,
near shore waves are 6 to 10 feet.

Monday night: Low pressure to our south will continue to bring
strong NE winds 20-30 kts gusting to 40 kts. Seas on the outer
waters 11 to 14 feet.

Outlook /Tuesday Night through Friday/...

Tuesday: Low risk for gale force winds with gusts up to 40 kt.
Rough seas up to 14 ft. Chance of rain.

Tuesday Night: Winds less than 25 kt. Rough seas up to 12 ft.
Chance of rain.

Wednesday through Wednesday Night: Winds less than 25 kt. Areas
of rough seas. Chance of rain.

Thursday: Winds less than 25 kt. Local rough seas. Rain likely.

Thursday Night: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Areas of rough seas. Rain likely.

Friday: Low risk for gale force winds with gusts up to 30 kt.
Rough seas up to 8 ft. Rain likely.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory until 8 PM EDT Tuesday for ANZ230-231-236-
     237-250-251.
     Gale Warning until 2 PM EDT Tuesday for ANZ232>235-254>256.

&&

$$

SYNOPSIS...Loconto/BW
NEAR TERM...Loconto/BW/Dooley
SHORT TERM...BW
LONG TERM...Loconto
AVIATION...Loconto/BW/Dooley
MARINE...Loconto/BW


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