Area Forecast Discussion
Issued by NWS Boston, MA

Home |  Current Version |  Previous Version |  Text Only |  Print | Product List |  Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
850
FXUS61 KBOX 081931
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
231 PM EST Fri Nov 8 2024

.SYNOPSIS...
A dry cold front will usher in a chilly and blustery airmass
tonight into Saturday. High pressure then quickly follows
Saturday night, before moving east of the region Sunday. Low
pressure system brings light rain Sunday evening and wrapping up
during the overnight. Low chance for shower early morning of
Veterans Day, otherwise dry conditions into mid week.

&&

.NEAR TERM /THROUGH TONIGHT/...
A dry cold front will cross southern New England and move
offshore by late this evening. Besides the wind shift to the
northwest, this is when the colder air will start to arrive.
Despite the clear skies, not expecting much radiational cooling.
The cold advection will be strong enough to maintain gusty winds
all night. Below normal low temperatures, mainly in the 30s
away from the immediate coast.

&&

.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
High pressure arrives from the west during the day Saturday,
then offshore Saturday night. Gusty northwest winds expected to
continue through the morning hours, then diminishing into
afternoon hours.

Dry weather and below normal temperatures continue through
Saturday night.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
Highlights:

* Dry for much of Sunday, but a low pressure system moving
 across northern New England will bring light rain during the
 evening and overnight hours.

* Drying trend for Veterans Day through mid-week. Mild
  temperatures Monday afternoon, but a cold front on Tuesday
  will bring a change in airmass and cooling trend for the rest
  of the week.

* Signs for unsettled conditions towards the end of next week,
  but there remains a lot of uncertainty.

High pressure drifts offshore on Sunday, but a dry day is
expected with increasing clouds. Still breezy, southwest wind
gust around 20 mph. Given the dry spell and MIN RH values 30 to
40 percent across a large portion of the CWA may need another
headline for elevated fire weather concerns. Overall a
seasonable afternoon, highs in the middle to upper 50s.

Heading past sunset, chances for rain start to increase, with
the 08/12z run of the NAM 3KM, light rain could arrive as early
as 00z/7pm for far western MA. But think for much of our CWA it
will be closer to 03z/10pm. This is associated with our a system
coming out of the Great Lakes. Mid-level ridging aloft
deamplifies as a broad trough brings our next rain chances.
While there is sufficient PWATs, 1.2" to 1.5", which is 250+
percent of normal for the day, the best forcing is across
northern New England. Would like to see better forcing near us
for a good widespread soaking of rain, am thinking the rain we
get Sunday night into Monday morning will be showery. 08/12z
ensemble probabilites show a spread in precipitation, the ECMWF
ENS gives 80-90% of 0.1" across all of southern New England
through 12z Monday. While the GEFS ENS is less optimistic with
60-80% along and east of I-95 and areas northwest are 20-50%.
Thinking areas long the south coast will have the best potential
for wetting rain and less chance the further north you go.
Drying conditions for Veterans Day, with highs slightly warmer
than Sunday in the low and middle 60s.

Surface high pressure builds in Tuesday and Wednesday with mid-
level ridging into the northeast. A weak frontal boundary moves
through on Tuesday, bring a reinforcement of cooler air. This
will set the stage for cooler conditions, highs on Tuesday in
the upper 50s and low 60s. And for Wednesday highs are on either
side of 50F.

Late next week there are signs in a pattern shift in the mid-
levels and the next chance for precipitation and/or snow showers
in the higher elevation of northern New England. There are
still unknowns at this point given the variations among the
deterministic models, but something to keep an eye on heading
Thursday into Friday. Nevertheless, the cooler temperature trend
continues late week as high temperatures remain in the upper
40s and low 50s.

&&

.AVIATION /20Z FRIDAY THROUGH TUESDAY/...
Forecast Confidence Levels:

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

Through Saturday Night...High Confidence.

VFR. Gusty W to NW winds into Saturday morning. Gusty NW winds
diminish some Saturday afternoon into Saturday night. Scattered
cloud bases down to 040-060 with the passage of a cold front
late this afternoon and evening.

KBOS TAF...High Confidence in TAF.

KBDL TAF...High confidence in TAF.

Outlook /Sunday through Wednesday/

Saturday Night through Sunday: VFR. Breezy.

Sunday Night: MVFR/IFR conditions possible. Breezy. RA.

Veterans Day: Mainly VFR, with local MVFR possible. Breezy.
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.

Gale Warnings and Small Craft Advisories continue into Saturday
morning as a cold front crosses the waters this evening and
overnight. Winds and waves will gradually diminish Saturday
afternoon with Gale Warnings transitioning to Small Craft
Advisories at that time.

Outlook /Sunday through Tuesday/...

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

Sunday: Winds less than 25 kt.

Sunday Night: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Local rough seas. Rain.

Veterans Day: Moderate risk for Small Craft Advisory winds with
gusts up to 25 kt. Areas of rough seas. Rain.

Monday Night: Winds less than 25 kt. Local rough seas.

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

&&

.FIRE WEATHER...
The prolonged period of dry weather coupled with a very dry
ground will continue to result in elevated fire weather concerns
through Saturday. Plenty of sunshine is expected. Afternoon
high temperatures Saturday in the 40s to lower 50s. Northwest
wind gusts up to 35 mph are expected. Minimum afternoon relative
humidity values Saturday are expected to range between 25 and
40 percent.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Red Flag Warning until 6 PM EST Saturday for CTZ002>004.
MA...Red Flag Warning until 6 PM EST Saturday for MAZ002>024-026.
RI...Red Flag Warning until 6 PM EST Saturday for RIZ001>008.
MARINE...Small Craft Advisory from 7 PM this evening to 10 AM EST
     Saturday for ANZ230-233>237.
     Gale Warning from 7 PM this evening to 1 PM EST Saturday for
     ANZ231-232-250-251-254.
     Gale Warning from 7 PM this evening to 10 AM EST Saturday for
     ANZ255-256.

&&

$$

SYNOPSIS...Belk/Dooley
NEAR TERM...Belk
SHORT TERM...Belk
LONG TERM...Dooley
AVIATION...Belk/Dooley
MARINE...Belk/Dooley
FIRE WEATHER...Belk/Dooley