BOX issues Area Forecast Discussion (AFD) at Feb 10, 12:30 PM EST329
FXUS61 KBOX 101730
AFDBOX
Area Forecast Discussion
National Weather Service Boston/Norton MA
1230 PM EST Mon Feb 10 2025
.SYNOPSIS...
Dry and cold conditions through Tuesday with below normal
temperatures. Our weather pattern then becomes more active again
with a coastal low pressure passing to our south Tuesday night
into Wednesday, that may bring light snow to the south coast.
Then monitoring a stronger storm Wednesday night into Thursday
which may bring snow and mixed wintry precipitation. Dry and
cold weather returns for Friday and Saturday as high pressure
builds into the region. Another storm may impact the region
next Sunday but details are uncertain.
&&
.NEAR TERM /THROUGH TONIGHT/...
945 AM update...
A weak shortwave will be moving through New England but
moisture is quite limited. Expect sct-bkn strato-cu to develop
and can't rule out a few flurries in northern MA as some Great
Lakes moisture gets carried eastward into the region on WNW
flow. It will also become a bit breezy with deep and well mixed
boundary layer in place. Soundings support some gusts to 20-25
mph at times. Below normal temps with highs upper 20s to mid
30s.
Previous discussion...
Southern New England is positioned between several synoptic
systems today. A low pressure over the Maritimes and a front to
our north, and a sprawling high pressure nosing into the Ohio
Valley from Alberta. This should lead to plenty of sunshine
today, along with some diurnal clouds. Expecting another gusty
day once mixing gets going. Below normal temperatures continue.
&&
.SHORT TERM /TUESDAY/...
The high pressure over the Ohio valley today should move closer
to our region for Tuesday. Diurnal clouds should dissipate with
sunset, but higher level clouds should be streaming overhead
into Tuesday. With a fairly fresh snowpack and light winds,
favored the lowest temperature guidance. The only concern will
be the amount and thickness of these higher clouds. That could
reduce the effectiveness of the radiational cooling. Dry weather
continues into Tuesday. Increasing clouds though as a low
pressure passes by well to our south. Very low risk for some
light towards the southern coastal waters late in the day. Below
normal temperatures continue.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
Key Messages:
* Some light snow may reach the south coast and Cape and Islands
late Tuesday/early Wednesday
* Another system comes through Thursday that may bring more
wintry precipitation
* Quiet Friday before yet another system may move into the
northeast this weekend
Details...
A weak low expected to move offshore Tuesday night is expected
to remain well to our south, but the chance for some light snow
showers along its northern edge cannot be ruled out still. The
ECMWF and GEM have also joined the GFS in taking this low more
to the south. Probabilities for even the lightest accumulations
for >0.01 inches QPF over 24 hours (ending 12z Wednesday) remain
primarily across the south coast and along the Cape and
Islands. The GEFS continues to keep probs low, with the highest
probs for any measurable precipitation to coastal CT and south.
The GEPS is also still picking up higher probs particularly in
the CT Valley, with the chances for >0.1 inches QPF reaching 30%
there by the end of the day Wednesday. Probs for an inch or
more of snow also remain below 50% and restricted to the south
coast and Cape/Islands. Temperatures aloft remain cold enough to
support these brief possible snow showers, and lows Tuesday
night are expected to be in the teens and 20s. Aside from any
early morning snow showers, Wednesday looks to be a quiet day.
The next system makes its approach Thursday, notably stronger
than the Tuesday one. A strong shortwave from the Rockies will
progress eastward, and its associated surface low will likely
reach the Northeast around early Thursday morning. A scenario
gaining some more traction in the latest runs has a secondary
low developing over or just to the SW of southern New England,
then really strengthening once it reaches the Gulf of Maine as
the primary low off to its west weakens. From run to run, the
strength of each low does fluctuate a bit across the GFS, GEM,
and ECMWF, but the signal for this secondary low does persist.
Deterministic guidance, particularly the ECMWF and GEM, usher in
warmer air aloft further north into much of (if not all) of MA
by Thursday afternoon, which is a good indicator for some mixed
precip; the GFS keeps this warmer air along the south coast. The
northern extent of this warmer air would depend on the strength
of the primary low and its associated warm air tracking to the
west of the secondary low, so this will be something to monitor.
Highs Thursday may reach the 40s, especially across SE MA, RI,
and the Cape/Islands, with highs in the interior mainly in the
upper 30s.
Another thing to note is that in the ensembles, QPF for
Thursday has trended down a bit with each run. Mean QPF values
over 24 hours ending 00z Friday now sit primarily around 0.3 to
0.4 inches for the GEFS and EPS. The GEPS is still an outlier,
with mean QPF values close to 0.8 inches in some spots and
generally at 0.6-0.65 inches everywhere else. But even with
these high values, they have still trended down from previous
runs. With the warmer air advecting in with this system,
possible snow accumulations still remain low and freezing rain
remains a threat, especially in the interior where temperatures
may be more marginal. More details will become clearer regarding
this storm as we get closer to it.
Following this system, decent ridging and its high pressure
will build in over the Northeast for Friday into Saturday.
Colder air moves back in and highs Friday may return to the low
30s and high 20s, with lows overnight in the single digits and
teens.
Yet another system may move in Saturday night into Sunday
morning, but timing, track, and ptype remain uncertain this far
out. Another strong shortwave ejects from the Rockies and moves
eastward. Its surface low would move through the region sometime
Sunday, but once again, timing is still uncertain. The WAA
associated with this low may also bring a mix of wintry
precipitation, which may pose issues considering the colder
surface temperatures that will be present before this system
arrives. Again, this track may change quite a bit considering
that it is still well into the future.
&&
.AVIATION /17Z MONDAY THROUGH FRIDAY/...
Forecast Confidence Levels:
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
Through Tuesday...High confidence.
VFR through the period. BKN cigs around 5k ft this afternoon
will erode this evening. Increasing high clouds Tue. WNW gusts
to 20 kt this afternoon becoming light tonight, then SW 10-20 kt
Tue.
Tuesday night...Moderate confidence.
Uncertainty with northern extent of snow area as it approaches
the south coast. Best chance for a period of snow with IFR vsbys
and minor accum will be over the Islands with lower probability
along the south coast. VFR north of HFD-PVD-PYM.
KBOS TAF...High Confidence in TAF.
KBDL TAF...High Confidence in TAF.
Outlook /Wednesday through Friday/...
Wednesday: Mainly VFR, with areas IFR possible. Slight chance
SN.
Wednesday Night: Mainly IFR, with areas MVFR possible. Breezy.
Chance SN.
Thursday: Mainly IFR, with areas MVFR possible. Breezy. SN
likely, chance RA.
Thursday Night: Mainly VFR, with local MVFR possible. Breezy.
Friday: VFR. Breezy.
&&
.MARINE...
Forecaster Confidence Levels:
Low - less than 30 percent.
Medium - 30 to 60 percent.
High - greater than 60 percent.
High pressure well to the west will lead to gusty NW winds
across the waters today. Gusts should generally remain less than
20 kt today, but rough seas will take longer to subside across
the outer MA coastal waters. Small Craft Advisories continue
into tonight. High pressure passing south of New England should
be more in control of the weather over the waters Tuesday.
Outlook /Tuesday Night through Friday/...
Tuesday Night: Winds less than 25 kt. Chance of snow.
Visibility 1 to 3 nm.
Wednesday: Winds less than 25 kt. Seas locally approaching
5 ft. Chance of snow. Visibility 1 to 3 nm.
Wednesday Night: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Areas of rough seas. Rain likely, chance of
snow. Visibility 1 to 3 nm.
Thursday: Low risk for Small Craft Advisory winds with gusts up
to 25 kt. Rough seas up to 9 ft. Rain likely. Local visibility
1 nm or less.
Thursday Night: Low risk for Small Craft Advisory winds with
gusts up to 30 kt. Rough seas up to 8 ft. Slight chance of
rain.
Friday: Moderate risk for Small Craft Advisory winds with gusts
up to 30 kt. Areas of rough seas.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory until 1 AM EST Tuesday for ANZ250.
Small Craft Advisory until 4 AM EST Tuesday for ANZ254.
Small Craft Advisory until 1 PM EST this afternoon for ANZ255.
&&
$$
SYNOPSIS...Belk/Hrencecin
NEAR TERM...Belk/KJC
SHORT TERM...Belk
LONG TERM...Hrencecin
AVIATION...KJC/Hrencecin
MARINE...Belk/Hrencecin
Source:
BOX issues Area Forecast Discussion (AFD) at Feb 10, 12:30 PM EST----------------
If I'm using your data in a way that is against your terms please email the team at "threatweb@pupswoof117.com"! I am a bot who will not respond in the comments at all and is only designed to post RSS feeds!
