Old Res Weather

Area Forecast Discussion
for Boston / Norton, MA

        
000
FXUS61 KBOX 221928
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
228 PM EST Sun Feb 22 2026

.WHAT HAS CHANGED...
Blizzard Warnings were expanded to all of southern New England 
except northwest MA. Winter Weather Advisory for Nantucket upgraded 
to a Blizzard Warning. 

&&

.KEY MESSAGES...

- A powerful winter storm brings significant to extreme impacts
  to much of the region later tonight into Monday, with heavy 
  snowfall, damaging winds and blizzard conditions. Worst of the
  impacts will be felt south and east of the I-95 corridor. 

- Expecting significant coastal impacts with areas of moderate
  coastal flooding during the late tonight/early Monday morning
  high tide across eastern MA. The greatest impacts will be 
  from Plymouth county southward to Cape Cod and the Islands.

&&

.DISCUSSION...
KEY MESSAGE 1...A powerful winter storm brings significant to 
extreme impacts to much of the region later tonight into 
Monday, with heavy snowfall, damaging winds and blizzard 
conditions. Worst of the impacts will be felt south and east of
the I-95 corridor. 

Overview: Potent upper level trough/shortwave becoming 
negatively tilted and closing off south of New Eng with 
significant height falls over 300m will result in explosive 
cyclogenesis tonight into Monday morning. 24 hr pressure falls 
exceed 35 mb in 24 hr period which more than satisfies bomb 
cyclone criteria. This is a classic climatological set up for a
blockbuster blizzard for the coastal plain with sub 970 mb low 
tracking near the benchmark. Very good model agreement on track 
and intensity so we have high confidence on impacts across the 
region. Still some differences in QPF for the storm event but we
leaned toward hi- res guidance which should have a better 
handle on mesoscale processes with the banding across the 
region. Exact placement of mesoscale bands and localized 
heaviest snowfall may still shift until we can see where banding
sets up but overall high confidence on snowfall amounts. We 
have noted a slight shift in the storm track to a bit south of 
the benchmark which would increase confidence of max snowfall 
occurring in SE MA, but lower confidence in amounts across 
interior northern and western MA/CT.

Timing and snowfall amounts: Some light snow may develop by 
late afternoon, but main accumulating snow should hold off 
until 7-11 pm from SW to NE. Then we await the very heavy snow 
band which will be moving up from the south associated with 
strong low level warm advection/frontogenesis enhanced by the 
low level jet which will also be lifting northward. This will 
initially be a laterally translating band lifting northward 
across the region between 3 am and 10 am. Snowfall rates during 
this time will likely reach 2-4"/hr at times, especially across 
RI and eastern MA given strong and deep forcing for ascent 
through the DGZ and some instability aloft supporting the heavy 
snowfall rates and possible thundersnow. Then it will transition
to a pivoting band late morning into the afternoon and where 
this pivots will determine where heaviest snowfall sets up and 
potential for amounts exceeding 2 feet. Overall looking at 18-24
inches from eastern CT and central MA through RI and eastern 
MA. While QPF is less across eastern CT and central MA SLRs will
be greater. Within this area we think the best chance of seeing
locally up to 30 inches will be across SE MA where pivoting 
band is most likely which fits climatology of a mid level low 
tracking near or a bit south of the benchmark. For the Cape and 
Islands we have amounts dropping off a bit over the outer Cape 
and especially Nantucket where snow may briefly mix or change to
rain in the morning before flipping back to snow, but still 
looking at 8-12 inches for Nantucket and 12-18 inches for the 
outer Cape. Across western MA/CT there is a bit more uncertainty
as this area will be on the western fringe of the heaviest 
snow. Looking at 8-14 inches in this area. Given the strong wind
gusts across the entire region, blizzard conditions are 
expected for much of the region and so the blizzard warnings 
were expanded westward. Very poor vsbys with whiteouts at times 
and blowing and drifting are likely, especially late tonight 
into Monday afternoon. The intensity of the snow will begin to 
taper off around midday in western New England and mid to late 
afternoon across eastern MA, ending by late afternoon in the 
west and 7-10 pm across SE MA and Cape Cod. 

Impacts: We can't stress this enough but this storm will likely 
bring extreme to destructive impacts south and east of the I-95 
corridor, especially SE MA and Cape Cod due to the combination of 
heavy wet snow and damaging wind gusts. Heavy wet snowfall amounts 
up to 2 ft with damaging winds presents a serious concern for tree 
damage and power outages. Temps across SE MA will be around 32F 
during the brunt of the heavy snow late tonight and Mon morning, 
then will begin to fall into the 20s during Mon afternoon. Further 
north and west into central and NE MA and western MA/CT, temps will 
be in the 20s for the entire event so the snow will be of a drier 
consistency which will help to mitigate these impacts somewhat. 
These areas could still see some power outages but on a much lesser 
scale than what is experienced south and east of I-95. In terms of 
travel, it will be near impossible during the period of heaviest 
snow late tonight through the morning with the heavy snowfall rates 
and whiteouts and as such travel is highly discouraged. 

Damaging wind: Wind will also be a serious concern, especially along 
and south and east of I-95 corridor. 65 to 75 kt low level jet lifts 
north across the coastal plain late tonight into Mon before pivoting 
across SE MA and Cape/Islands. We've seen stronger LLJs but what is 
different with this event is we have a favorable thermodynamic 
environment to promote efficient mixing. As such, soundings support 
hurricane force gusts to 70-80 mph for the outer Cape and Nantucket, 
55-65 mph southern RI and SE MA and 40-50 mph for the interior north 
and west of I-95. These winds alone will be strong enough alone for 
tree damage and power outages south and east of I-95, not even 
considering the impacts for heavy wet snow. 

KEY MESSAGE 2...Expecting significant coastal impacts with areas
moderate coastal flooding during the late tonight/early Monday
morning high tide across eastern MA. The greatest impacts will 
be from Plymouth county southward to Cape Cod and the Islands.

A storm surge of 2-3' at the time of high tide early Monday
morning (2AM-5AM) will likely yield moderate coastal flooding 
from Plymouth county southward to Cape Cod and the Islands. 
Therefore a Coastal Flood Warning continues for this portion of
the coastline. Farther northward from Boston to the NH border, 
there is more uncertainty, with a higher probability of minor 
flooding. Therefore, a Coastal Flood Advisory posted there.

The greatest storm surge (up to 4 ft) appears to occur during 
low tide Monday (9-10AM). However, there could be enough storm 
surge for minor coastal flooding during the late day high tide 
(3-6PM). Although, given the astro tide is lower and winds will
be more northerly, only expecting minor flooding. Nonetheless, 
a Coastal Flood Watch remains in effect for this Monday
afternoon high tide to account for any storm track changes,
including timing.

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
Forecaster Confidence Levels...

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

Today...Moderate confidence.

MVFR with ENE winds 6-11 kts. Light snow showers/flurries 
possible ahead of the approaching winter storm.

Tonight through Monday Morning... High Confidence

MVFR turning IFR/LIFR as light snow overspreads the region 
between 22-04z. Wind increase out of the NE this evening/tonight 
with gusts 20-40 kts, increasing to 40-50 kts after midnight.
Gusts 50-70 kts possible in eastern MA/RI, strongest for the 
Cape and Islands. Snow rates pick up overnight, becoming very 
heavy, likely after 06Z. Heavy blowing snow/blizzard conditions
likely, especially further east. Significant LLWS with 70 knots
of wind down to 500 feet.

Monday Afternoon and Night... High confidence.

Gradually improving to VFR from W to E Monday afternoon. VFR by
00Z across the western half of southern New England, but likely
taking until midnight to reach the east coast of MA. Snow rates
decrease in the afternoon with remaining snow exiting the east 
by midnight. Winds gradually diminish in the afternoon and 
evening, especially after midnight. However, gusts 40-55 kts are
expected through the evening across the more east terminals.

KBOS Terminal...Moderate confidence in TAF (Light snow arrival)

Light snow showers possible late this afternoon-evening.
Steadier snow arrives 00-03Z. Snow becomes heavy with hourly 
rates greater than 1" likely after 09z. 

Blizzard conditions expected with gusts up to 55 kts developing
by daybreak Monday along with wind shear. Snow rates decrease 
in the afternoon. Light snow continues Monday evening, exiting 
by midnight. 

KBDL Terminal...Moderate confidence in TAF.

MVFR today/tonight. Light snow showers possible this
afternoon/early evening. Uniform light snow arrives 00-02Z. 
Heavy snow with hourly rates greater than 1" likely after
07/08z. Heavy snow continues Monday morning, with rates
decreasing mid-late morning. Light snow continues before exiting
late afternoon/evening. 

Winds increase tonight, becoming strong especially after 
midnight- toward daybreak. Gusts 40-45 kts by 12Z through the 
afternoon resulting in blizzard conditions. Winds gradually 
decrease Monday afternoon- evening.

Outlook /Tuesday through Friday/...

Tuesday: VFR. Breezy. 

Tuesday Night: VFR. Chance SN.

Wednesday: Mainly IFR, with local MVFR possible. Breezy. SN
likely, chance RA.

Wednesday Night: VFR. Breezy. 

Thursday: VFR. Chance RA, chance SN.

Thursday Night: Mainly VFR, with areas IFR possible. Breezy. RA
likely, chance SN.

Friday: Mainly VFR, with local MVFR possible. Breezy. Chance
SN, slight chance RA.

&&

.MARINE...
Forecaster Confidence Levels...

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

Very dangerous and life threatening storm for mariners late tonight 
through Monday. Storm warnings are in effect. We expect wind gusts 
55-65 kt peaking late tonight into Monday afternoon. A few hurricane 
force gusts are likely. Winds will begin to diminish from the peak 
of the storm from late afternoon through Mon evening and drop below 
gale force late Mon night. Seas peaking at 15-25 ft Mon afternoon 
and evening with the highest seas over the eastern MA outer waters. 
Near zero vsby at times in heavy snow late this evening into Monday, 
possibly briefly changing to rain east of Chatham to Nantucket.

Outlook /Tuesday through Friday/...

Tuesday: Low risk for Small Craft Advisory winds with gusts up
to 25 kt. Rough seas up to 13 ft. 

Tuesday Night: Winds less than 25 kt. Local rough seas. Chance
of snow. 

Wednesday: Low risk for Small Craft Advisory winds with gusts
up to 25 kt. Local rough seas. Rain likely, chance of snow.
Areas of visibility 1 to 3 nm.

Wednesday Night: Winds less than 25 kt. Areas of rough seas.
Slight chance of rain. 

Thursday: Winds less than 25 kt. Local rough seas. Chance of
rain. 

Thursday Night: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Local rough seas. Rain likely. Local
visibility 1 to 3 nm.

Friday: Winds less than 25 kt. Areas of rough seas. Chance of
rain. 

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Blizzard Warning until 7 AM EST Tuesday for CTZ002>004.
MA...Blizzard Warning until 7 AM EST Tuesday for MAZ004>007-009>024-
     026.
     Winter Storm Warning until 7 AM EST Tuesday for MAZ002-003-008.
     Coastal Flood Advisory from 1 AM to 7 AM EST Monday for MAZ007-
     015-016.
     Coastal Flood Warning from 1 AM to 7 AM EST Monday for MAZ019-
     022>024.
     Coastal Flood Watch from Monday afternoon through Monday 
     evening for MAZ019-022>024.
RI...Blizzard Warning until 7 AM EST Tuesday for RIZ001>008.
MARINE...Storm Warning from 10 PM this evening to 1 AM EST Tuesday for 
     ANZ230>237-250-251-254>256.

&&

$$

DISCUSSION...KJC
AVIATION...Mensch
MARINE...KJC