Somerville, Massachusetts 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

845
FXUS61 KBOX 142321
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
621 PM EST Thu Nov 14 2024

.SYNOPSIS...
A storm system will move westward over the Canadian Maritimes
Friday into the weekend, bringing with it increasing cloud
cover Friday afternoon/evening and gusty winds and continued dry
conditions. A warming trend is expected this weekend into early
next week with above normal temperatures expected. A cold front
then moves through on Monday which may bring a chance for
scattered light showers followed by dry and blustery conditions
Tuesday and Wednesday with seasonable temperatures through at
least mid week.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
Highlights:

* Dry and cool overnight, with breezy conditions along the eastern
  coast of MA.

Bone dry atmosphere across southern New England as the dew
point temperature fell into the single digits and teens, not to
forget to mention a couple ASOS did report below zero Td! High
cirrus clouds move in from the west tonight, this will help to
keep temperatures from radiating fully, still a cold night in
the 20s. Areas furthest east will likely have the least in the
way of cloud cover, but will have the best mixing of the
boundary layer. Cape and Islands remain in the 30s overnight.

Any lingering wind ease shortly after sunset, with the exception of
eastern coastal MA. Here, winds remain out of the north 6 to 10 mph
with gust up to 20 mph. The exception is outer Cape and Nantucket
where gust to 25 mph are possible.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
Highlights:

* Red Flag Warning for all of southern New England, details found in
  the Fire Weather section of the AFD.

* Coastal Flood Statement for minor splashover for the Friday
  A.M. high tide for eastern coastal MA and the southern coastal
  MA and RI, details found in the Tides & Coastal Flood section
  of the AFD.

Surface high pressure remains over southern New England with a more
robust coastal low pressure system off the coast of Nova Scotia
retrogrades west and provides strengthening pressure gradient
and northwest flow on Friday winds occasionally gusting to 20-25
mph.

As the low pressure moves northwest it will send some moisture
westward, but not enough for any precip, in fact rain chances, what
little they were, have decreased to nill. Will have low to mid level
clouds shift into eastern MA by late afternoon, but otherwise a
mostly sunny day. Dew points have been difficult to nail down given
how dry it is. Started out with the 10th percentile of the NBM and
still had to nudge down values to get values in the teens. This will
result in min RH values in the upper teens and middle 20s. A milder
airmass will move into the region as 925 mb temps increase to +5C to
+6C. Highs should reach mid to upper 50s, cooler higher terrain.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
The retrograding coastal system begins to exit to the north on
Saturday but the lingering tight pressure gradient will lead to
continued gusty NW wings as high as 20-25 mph. At the synoptic scale
we`ll see a steadily building mid level ridge through the weekend
leading to moderating temperatures (highs back in the low 60s) and
dry weather. Winds diminish on Sunday as the pressure gradient
relaxes.

For the first half of next week another shortwave disturbance moves
through northern New England bringing briefly more zonal flow
overhead on Monday before ridging builds back in through mid week.
This Monday disturbance looks to be moisture starved and thus not
expecting much in the way of any rainfall. However, it will lead
once again to some gusty winds Monday and Tuesday.

On the whole we`re not looking at any appreciable storm systems with
real hopes of significant rainfall during the 6-7 day period. Tell
me if you`ve heard this before, but models are hinting at a more
substantial storm system on the tail end of the forecast period
(Thursday) or just beyond it. Fool me once, shame on you, fool me
twice, well...let`s just say that we`re not locking into any
solution yet but at the very least there are hopeful signs of a more
substantial rainfall event with the GFS/ECMWF/Canadian all in
agreement that a broad west coast ridge and east coast trough sets
up by the end of the week. That consensus inspires some hope, but as
we`ve seen before consensus amongst global guidance doesn`t always
mean correctness. Stay tuned.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
Forecast Confidence Levels:

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

00z TAF Update...

High confidence through Friday Night.

VFR. SCT-BKN cigs around 3500 ft Cape/Islands until 21z. High
clouds tonight, then 4-8k ft cigs developing across eastern MA
after 18z Friday through the overnight.

N-NE wind 5-15 kt this afternoon with gusts to 20-25 kt for the
Cape/Islands. Calm or light N wind tonight, up to 10-15 kt
Cape/Islands. NW wind 10-15 kt with G20 kt Friday.

KBOS TAF...High Confidence in TAF.

KBDL TAF...High Confidence in TAF.

Outlook /Saturday through Tuesday/...

Saturday through Sunday: VFR. Breezy.

Sunday Night: VFR.

Monday: VFR. Breezy. Slight chance RA.

Monday Night through Tuesday: VFR. Breezy.

&&

.MARINE...
Forecaster Confidence Levels:

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

Through Friday Night...High confidence.

Persistent wind gusts up to 25 knots continue into Friday night over
eastern waters with winds tonight out of the north and north to
northwest on Friday. Less wind over RI coastal waters. Rough seas
for the eastern outer waters through Friday night, 4-7 feet.

Small Craft Advisories will continue for eastern MA waters for
combination of wind gusts and rough seas through Friday night, and
for RI outer waters for marginal seas through tonight.

Outlook /Saturday through Tuesday/...

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

Saturday Night: Winds less than 25 kt. Seas up to 5 ft.

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

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

Monday: Winds less than 25 kt. Areas of seas approaching 5 ft.
Slight chance of rain.

Monday Night: Winds less than 25 kt. Seas up to 5 ft. Slight
chance of rain.

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

&&

.FIRE WEATHER...
     RED FLAG WARNING IN EFFECT FROM 7 AM TO 6 PM EST FRIDAY FOR
SOUTHERN NEW ENGLAND...

On Friday, northwest winds will increase with gusts to 20-25 mph. It
will remain quite dry with relative humidity values lowering between
20-25 percent for most of the region, except 30-40 percent over the
outer Cape.

Saturday will feature breezy northwest winds with gusts 20-25 mph.
Subsident flow and downslope component winds will promote another
dry day with relative humidity values between 20-35 percent in most
areas. This will increase concerns for critical fire weather
conditions.

Less breezy on Sunday with dry conditions. Next chance for any
rainfall will be with Monday`s system; however, wetting rain chances
are low. Breezy northwest flow will likely accompany the system.

We will continue to coordinate with our CT, MA and RI state fire
partners, but current indications are that Saturday may see another
round of warnings being issued.

&&

.TIDES/COASTAL FLOODING...
A coastal flood statement was issued for the eastern MA coast
including the Cape/Islands and the south coast of MA and RI
including Block Island for the potential for very minor flooding or
splashover at the Friday morning high tide.

Astronomical high tides are on the rise reaching 11.8 ft MLLW at
Boston Friday morning. With an expected surge around 1 ft combined
with wind wave energy from the NE, pockets of very minor coastal
flooding or splashover ares possible, especially along N to NE
facing beaches (Cape Ann, Scituate, Sandwich to Dennis on Cape Cod
and Nantucket Harbor). Similar, high tides are reaching near 5.9 ft
MLLW at Providence, an expected surge 1.3 ft combined with wind wave
energy from the NE, pockets of very minor coastal flooding or
splashover ares possible.

Astronomical tides peak during the late morning high tides on
Saturday and reaching near 12 ft MLLW at Boston on Saturday. Latest
surge guidance from Stevens Institute and ETSS is indicating a 0.5
to 1 ft surge. While winds are more NW, swell direction and wave
energy is from the NE. Once again, the favored locations for minor
flooding would be N and NE facing beaches. Coastal flood advisories
may be needed if surge values are closer to 1 ft.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Red Flag Warning from 7 AM to 6 PM EST Friday for CTZ002>004.
MA...Red Flag Warning from 7 AM to 6 PM EST Friday for MAZ002>024-
     026.
RI...Red Flag Warning from 7 AM to 6 PM EST Friday for RIZ001>008.
MARINE...Small Craft Advisory until 6 PM EST Friday for ANZ231-232-251.
     Small Craft Advisory until 7 AM EST Saturday for ANZ250-254-
     255.
     Small Craft Advisory until 7 AM EST Friday for ANZ256.

&&

$$

SYNOPSIS...BW/Dooley
NEAR TERM...Dooley
SHORT TERM...Dooley
LONG TERM...BW
AVIATION...BW/Dooley
MARINE...BW/Dooley
FIRE WEATHER...BW/Dooley
TIDES/COASTAL FLOODING...BW/Dooley