737
FXUS61 KBOX 061116
AFDBOX
Area Forecast Discussion
National Weather Service Boston/Norton MA
616 AM EST Fri Mar 6 2026
.WHAT HAS CHANGED...
No significant changes to the forecast.
&&
.KEY MESSAGES...
- Wintry mix along and north of I-90 and in the high terrain
winds down by early-mid morning...as well the burst of
plowable snowfall expected in north central/northeast MA. A
slippery early morning commute in these locations.
Otherwise...areas of fog, spotty very light rain/drizzle may
persist at times today & tonight. Any light freezing drizzle
confined mainly to the high terrain this afternoon, but black
ice may become more of a concern across the rest of the region
tonight.
- Turning milder with a warming trend this weekend and with risk for
showers Sat night into early Sun.
- Potential for a few days of unseasonably mild conditions next
week but have to watch a backdoor front to the north which
would bring much cooler temps. Accelerated snowmelt will lead
to steady rises on rivers and streams through the week. A
period of showers accompany a cold front late Wed-Thu, then
turning cooler towards the end of the week.
&&
.DISCUSSION...
KEY MESSAGE 1...Wintry mix along and north of I-90 and in the high
terrain winds down by early-mid morning...as well the burst of
plowable snowfall expected in north central/northeast MA. A Slippery
early morning commute in these locations. Otherwise...areas of fog,
spotty very light rain/drizzle may persist at times today & tonight.
Any light freezing drizzle confined mainly to the high terrain this
afternoon, but black ice may become more of a concern across the
rest of the region tonight.
The forecast remains on track early this morning. Rain and freezing
rain have changed to mainly sleet along and north I-90 early this
morning. This a result of 925T between -2C and -4C and the depth of
the cold layer between 4-5K feet. So the main risk for a very
localized areas of 0.25"+ of ice accretion will be in the southern
Berks/southern Worcester Hills and the highest locations of the CT
Hills. Fortunately...this risk looks to be very localized but power
outages are possible if these higher ice amounts are realized.
High resolution CAMS still indicate a period of 20-30 units of lift
in the snowgrowth region across north central and especially
northeast MA until 5-6 am. Given the soundings are isothermal...
intense lift will be needed to flip the sleet over to mainly snow.
The HREF/HRRR/RRFS all indicating a window for brief 1" per hour
snowfall rates possible through 6 am. A quick 2-4" of snow possible
in this region with localized 5-6" amounts not out of the question
in far northeast MA near the NH border. As we mentioned...the risk
of the heaviest snow will be until 6 am with the threat of
accumulating snow ending by 8-9 am in this region.
Otherwise...low pressure moves east of the region today but it will
combined with high pressure over the Canadian Maritimes. So although
the deeper/moisture forcing will have departed...persistent moist
northeast flow will result in dreary weather continuing the rest of
today into tonight. Spotty areas of very light rain/drizzle and fog
will also remain possible at times. Temps will remain in the 30s
today...but they should generally rise above freezing today outside
the highest terrain so road conditions will improve later this
morning and afternoon in areas impacted by the snow and ice early
this morning. W still need to watch for spotty freezing drizzle and
slippery travel into this afternoon in the highest terrain...mainly
at elevations over 1000 feet in the Worcester Hills/Berks. Perhaps
some black ice becomes more of an issue for the rest of the region
tonight with temps dropping to near freezing.
KEY MESSAGE 2...Turning milder with a warming trend this weekend and
with risk for showers Sat night into early Sun.
A mid-level ridge/surface high moves into the western Atlantic this
weekend directing milder S-SW flow into the region. While mid level
temperatures surge (850mb temps as high as 13C) poor mixing with an
inversion just off the deck will keep us from tapping into the truly
mild temps. Even so, compared to highs in the low to mid 30s on
Friday, Saturday will be warmer simply thanks to the winds at the
surface flipping from NE to S/SW. Expect a cloudy day with highs in
the mid 40s. A cold front then swings through Sunday, and out ahead
of that the combination of a 50-60 kts LLJ and a 1.25"+ PWAT plume
will lead to scattered light showers. The best consensus for timing
is overnight Saturday but still need to get some higher resolution
guidance to increase confidence, as some guidance wants to keep
shower chances around through the day on Sunday. The best chance
for this is southeast MA/coastal RI. For now sticking with
thinking that showers and clouds clear out later Sunday allowing
temps to further increase well into the 50s.
KEY MESSAGE 3...Potential for a few days of unseasonably mild
conditions next week but have to watch a backdoor front to the north
which would bring much cooler temps. Accelerated snowmelt will lead
to steady rises on rivers and streams through the week. A period
of showers accompany a cold front late Wed-Thu, then turning cooler
towards the end of the week.
The warm advection pattern continues through at least Tuesday before
our next frontal system brings rain and colder temps mid week. We
continue to see signals for highs well into the 60s by Tuesday but,
as is fairly typical this time of year, a high pressure over eastern
Canada may send a back door cold front into SNE around late Tuesday.
This has the potential to spoil the warm temperatures early,
especially for northeast MA. It could be a situation where we have a
very large temperature gradient between northeast MA and southwest
CT. Either way, confidence is higher that a cold front moves through
with precipitation and a cooler airmass around Wednesday. Before
that, though, increased temps and dewpoints will lead to significant
loss of our snowpack, so will have to monitor for rises on rivers
and streams.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
12z TAF Update...
Today...High confidence.
IFR/LIFR conditions dominate today. The threat of accumulating
snow/sleet across north central and northeast MA will come to an
end by 13z/14z. Meanwhile...south of I-90 in the lower
elevation, ptype mainly will be rain but some sleet may be mixed
in at times.
All precipitation tapers to mainly spotty light rain/drizzle by mid-
late morning. However...IFR/LIFR conditions likely persist
along with areas of fog due to continued onshore flow. Any
spotty freezing drizzle will mainly be confined to the highest
terrain by late morning and afternoon. NE winds 5 to 15 knots
with some 20-25 knot gusts possible near the coast and up to 30
knots or so for parts of the outer-Cape and Nantucket.
Tonight...High confidence.
IFR-LIFR persist. Winds slacken, but remain NE. Areas of spotty
light rain/drizzle and fog persist at times. We may have to watch
for spotty freezing drizzle/black ice with temps flirting with 32
degrees.
KBOS Terminal...Low confidence in TAF. The threat for
freezing rain/snow likely comes to an end by 14z but low
confidence how quickly temperatures rise above freezing so some
-FZDZ is possible until that happens.
KBDL Terminal...High confidence in TAF.
Outlook /Saturday through Tuesday/...
Friday Night: Mainly IFR, with areas MVFR possible. Breezy.
Areas BR, chance DZ, chance FZDZ, slight chance FZRA.
Saturday: Mainly IFR, with local MVFR possible. Breezy. Areas
BR, chance FZDZ, slight chance FZRA.
Saturday Night: Mainly IFR, with local MVFR possible. Breezy.
Chance RA.
Sunday: Mainly VFR, with local IFR possible. Breezy. Chance RA.
Sunday Night: VFR.
Monday through Monday Night: VFR. Breezy.
Tuesday: VFR.
&&
.MARINE...
Forecaster Confidence Levels...
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
Today and tonight...High confidence.
Large high pressure over the Canadian Maritimes coupled with low
pressure to the south of the waters will continue to generate NE
wind gusts of 20 to 30 knots and 4 to 8 foot seas today. Small craft
headlines posted for all open waters today. The gradient/NE winds
slacken tonight...but will need to continue small craft headlines
for all outer-waters given long NE fetch and lingering swell.
Outlook /Saturday through Tuesday/...
Friday Night: Winds less than 25 kt. Areas of rough seas.
Chance of drizzle, areas fog. Local visibility 1 to 3 nm.
Saturday: Winds less than 25 kt. Areas of rough seas. Patchy
fog.
Saturday Night: Moderate risk for Small Craft Advisory winds
with gusts up to 30 kt. Rough seas up to 8 ft. Chance of rain.
Sunday: Winds less than 25 kt. Seas up to 5 ft. Chance of rain.
Sunday Night: Winds less than 25 kt. Seas up to 5 ft.
Monday through Monday Night: Winds less than 25 kt. Areas of
seas approaching 5 ft.
Tuesday: Winds less than 25 kt.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Winter Weather Advisory until noon EST today for CTZ002>004.
MA...Winter Weather Advisory until noon EST today for MAZ002>015-
026.
RI...Winter Weather Advisory until noon EST today for RIZ001-003.
MARINE...Small Craft Advisory until 7 PM EST this evening for
ANZ231>235-237.
Small Craft Advisory until 7 PM EST Saturday for ANZ250-251-
254>256.
&&
$$
DISCUSSION...Frank/BW
AVIATION...Frank/BW
MARINE...Frank/BW
NWS BOX Office Area Forecast Discussion
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