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000
FXUS61 KBOX 152318
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
718 PM EDT Mon Apr 15 2024

.SYNOPSIS...
High pressure establishes itself over Southern New England
through midweek. It will bring abundant sunshine, dry weather,
seasonably mild temperatures and northwest breezes through
Tuesday. Dry Wednesday through at least mid-day Thursday before more
unsettled conditions develop late week. Above normal temperatures
return

&&

.NEAR TERM /THROUGH TUESDAY/...
Tonight

Gusty winds continue out of the NW/SW this evening, depending
on which side of a surface trough axis you are on. Southwest
gusts prevail over southeastern MA and The Cape with W/NW winds
elsewhere.

Broad cyclonic flow persists over The Northeast tonight. The
axis of a deep upper- level trough shifts to the east tonight
and supports a deep northwest flow over southern New England.
This will push the edge of a weak surface cold front through the
region and may support a few spotty showers over The South
Coast, Cape, and Islands this evening through about midnight.
Overall moisture in the column is very limited, so expect most
locations to stay dry. Any showers offshore will taper off after
midnight. Thereafter, clearing skies will prevail with steady
northwest winds. Background flow may be weak enough to allow the
boundary layer to decouple and support efficient radiational
cooling. Not very confident in a maximum radiational cooling
night, so elected to blend CONSMOS with the 25th percentile of
MinT guidance for the region which yields lows in the upper 30s
across interior/NW MA and low to mid 40s elsewhere.

&&

.SHORT TERM /TUESDAY NIGHT/...
Tomorrow

Very little change in the synoptic pattern tomorrow. Southern New
England will continue to be positioned west of a trough axis slowly
shifting east over The Atlantic Waters. This will continue to
support a deep northwest flow pattern over the region. Air mass will
be a bit cooler than on Monday, but efficient mixing will allow for
another mild afternoon with high temps in the mid to upper 60s. Low
70s will be a bit harder to achieve. Additionally, we can probably
expect some diurnal CU developing in the afternoon thanks to the
steep lapse rates.  Winds aloft don`t look overly impressive, so
would expect any gusts from boundary layer mixing to be limited to
about 20 mph. Overall a pleasant spring afternoon.


Tomorrow Night

Quiet weather continues again tomorrow night. A mid-level ridge axis
will build over southern New England along with surface high
pressure. This should support light winds out of the north and clear
skies allowing for efficient radiational cooling. Temperatures could
dip to freezing across interior/northwest MA with upper 30s to low
40s likely elsewhere.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Long term

Wednesday

Axis of a shortwave ridge aloft moves over the region with a
shortwave trough right on its tail.  A mainly dry column on
Wednesday will keep precip associated with the shortwave out until
late Wednesday night.  The shortwave will bring high clouds and
filtered sunshine to region Wednesday. This will keep high temps
down a bit compared to Tuesday only reaching the low to mid 60s
inland, and low to mid 50s along the immediate coastlines.

Thursday

Shortwave ridge moves north, while the shortwave trough breaks down,
but still sends some cyclonic vorticity into the region. Mid and
upper level moisture increases late Wednesday into Thursday.
However, PWATS will be on the low side topping out near 0.8 to 0.9
inches. With weak forcing and low level dry air, probabilities for
greater then 0.1 inches of rain from the LREF is less then 50%. With
cloud cover and wet conditions around, High temperature only top
into the low 50s region wide esspically with onshore flow. Winds
Thursday will be on the blustery side with easterly wind gusts of 15-
20mph.

Friday

Latest model guidance is trending drier for the end of the work week
with another shortwave ridge moving through along with drying mid
levels. Even though the chance for rain is decreasing, clouds will
continue to be around with more high level cirrus moving in ahead of
a closed trough over the Great Lakes, and some low to mid level
diurnal stratocumulus. Highs top out in the upper 50s with low 60s
possible. Winds remain a bit gusty out of the south at 10-15mph.

Saturday and Sunday:

Forecast confidence for next weekend is quite low right now with
large timing differences among model guidance. The upper level
closed low over the Great Lakes looks to weaken as it moves east
towards the region. This could bring a cold front and isolated
showers to the region, however, not every source of guidance is in
agreement that the cold front will actually make it into SNE. Stuck
with the NBM which gives 30-40% POP`s for Saturday and 10-20% for
Sunday. As for temps over the weekend, highs rebound back into the
low to mid 60s, but will likely end up on the lower side if rain
ends up falling during the daytime hours.

&&

.AVIATION /23Z MONDAY THROUGH SATURDAY/...
Forecast Confidence Levels:

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

00Z TAF Update:

Tonight: High confidence.

VFR. Outside chance at a shower affecting Cape/Islands terminals
late tonight/midnight. WNW winds continue but slacken to around
5-8 kt.

Tuesday: High confidence.

VFR mainly SKC. NW winds increase to 8-12 kt with gusts to 20
kt starting mid-morning and continuing till sundown. There is a
low chance for sea breezes to develop mid to late morning before
better mixing kicks them out by early afternoon

Tomorrow Night: High Confidence.

VFR. Steady NW winds becoming more N after 06Z.

KBOS TAF...High confidence in TAF.

VFR. Low chance a sea breeze sneaks in between 14-18z tomorrow
esspically since one almost made it in today. Otherwise winds
remain NW becoming gusty after 18z.

KBDL TAF...High confidence in TAF.

VFR. NW winds becoming gusty in the afternoon.

Outlook /Wednesday through Saturday/...

Wednesday: VFR.

Wednesday Night: VFR. Chance SHRA.

Thursday through Thursday Night: VFR. Breezy. Chance SHRA.

Friday: Mainly VFR, with local MVFR possible. Slight chance
SHRA.

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

Saturday: VFR. Breezy. Chance SHRA.

&&

.MARINE...
Forecaster Confidence Levels:

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

Tonight through tomorrow night

High pressure begins to work its way over the coastal waters tonight
through mid-week. This will support subsiding seas and diminishing
winds across the coastal waters through tomorrow night. Light
west/northwest winds tonight and tomorrow will become light out of
the north tomorrow night. Seas fall below SCY criteria over the
coastal waters after midnight.

Outlook /Wednesday through Saturday/...

Wednesday: Winds less than 25 kt.

Wednesday Night: Winds less than 25 kt. Chance of rain showers.

Thursday: Winds less than 25 kt. Seas locally approaching 5 ft.
Chance of rain showers.

Thursday Night through Friday: Winds less than 25 kt. Areas of
seas approaching 5 ft. Slight chance of rain showers.

Friday Night through Saturday: Winds less than 25 kt. Areas of
seas approaching 5 ft. Chance of rain showers.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory until 2 AM EDT Tuesday for ANZ254>256.

&&

$$

SYNOPSIS...Loconto/KS
NEAR TERM...RM
SHORT TERM...RM
LONG TERM...KP
AVIATION...RM/KP
MARINE...RM/KP