Old Res Weather

Lexington, Massachusetts, USA

35°F

2/16/2025 7:17pm

Lexington Conditions: Clear
Temperature: 35.1°F / 1.7°C
Dew Point: 32.4°F
Relative Humidity: 90%
Wind: Calm, 10-min avg: Calm, gust: None
Barometer: 29.00 in Falling Slowly
Visibility: 10 miles
Rain Today: 0.01 in
UV Index: $VPuv None

Area Forecast Discussion
for Boston / Norton, MA

        
000
FXUS61 KBOX 232257
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
557 PM EST Sun Nov 23 2025

.SYNOPSIS...
Overcast with isolated sprinkles or flurries through mid evening
as weak low pressure moves through northern New England, with
decreasing clouds overnight. Blustery but dry weather for
Monday, with increasing clouds for Monday evening. A warm front
will bring a period of rain from late Tuesday into Wednesday 
morning, mild with a continued chance of showers Wednesday into 
Wednesday night ahead of an approaching cold front. Cooler and 
blustery conditions follow behind the front for Thanksgiving 
Day, then windy and cold weather for next Friday and Saturday.
More seasonable Sunday as high pressure moves offshore.

&&

.NEAR TERM /THROUGH MONDAY/...
100 PM Update:

Key Messages: 

* Overcast with a flurry or sprinkle possible through mid-evening 
  but nothing worse. Decreasing cloudiness after midnight except 
  over the Cape and Islands.

Details:

Midlevel cloud canopy has overspread Southern New England, in 
association with a fast-moving Clipper low centered over the St. 
Lawrence River Valley in NW NY. Pretty favorable ascent with New 
England being located in the poleward exit region of a midlevel 
jetstreak - this jetstreak seen in WV imagery as the enhanced 
dryslot seen racing thru eastern PA. However much of the returns 
seen on regional radar mosaic have not amounted to much at all as 
drier air below cloud base appears to be winning out. It also looks 
like sustained precip will be tougher to come by in Southern New 
England given the drier punch of air aloft and better (deeper) 
saturation confined to interior northern New England. Wouldn't rule 
out a sprinkle or flurry at worst through early to mid evening as 
low pressure moves through but that will likely be the worst of it 
with considerable cloud cover to be the rule. 

Decreasing cloud cover after midnight in most areas, though there 
may be leftover ocean-enhanced cloudiness near the Cape and Islands 
as winds become NWly with some marginal ocean-enhanced instability 
as 925-850 mb thermal trough moves overhead. Early cloud cover and 
then NW winds around 5-10 mph increasing toward the pre-dawn hrs 
should lead to lows in the mid 20s to around freezing, with mid 30s 
Cape and Islands.

&&

.SHORT TERM /MONDAY NIGHT/...
100 PM Update:

Key Messages: 

* Blustery with dry weather Monday. 

* Early lows Mon night, but temps rise before daybreak with 
  increasing clouds. 

Details: 

Mostly clear with dry weather Mon, but will also see some blustery 
northwest winds. More shallow mixing (mixing depths to around 900 mb 
per BUFKIT profiles) should keep gusts in the 20 to 25 mph range 
from mid-morning to early afternoon before subsiding by mid-
afternoon to sundown. Highs should top out in the 40s, with low 40s 
terrain and mid/upper 40s lower elevations, coastal plain and the 
cities. 

Initial WNW winds then slacken early Mon night as sfc ridge of high 
pressure moves offshore. Continued easterly translation of the high 
to permit a moderately-strong warm advection regime to develop for 
the second half of the night, with increasing SW winds 5-10 mph and 
as well as an increasing coverage of mid to high clouds. This should 
allow for early lows in the mid 20s to around freezing, then rise 
into the 30s toward daybreak.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Key Messages: 

* A period of widespread rain late Tue into Tue evening, 
  tapering off late Tue night

* Rather mild with a chance of showers Wed into Wed evening

* Cooler and blustery Thursday, then windy and cold Fri & Sat. 
  
* Seasonably cool Sunday with a low risk of showers

Tuesday into Wednesday...

Fast moving deamplifying shortwave lifts NE from the Gt Lakes Tue 
passing to the north Tue night. High pres just offshore Tue will 
provide dry weather through the morning with temps a bit above 
normal as SW flow becomes established. Then increasing moisture and 
lift ahead of a warm front will result in rain quickly overspreading 
the region from W to E late Tue into Tue evening. Despite 
deamplifying shortwave a 40-50 kt low level jet will advect PWATs 
around an inch into SNE and enhance low level convergence, with 
favorable right entrance region of upper jet so expect a period of 
widespread rain Tue evening. It's a quick moving system with a dry 
slot moving into the region 06-12z so expect steady rain to end 
before daybreak Wed, but could see rainfall 0.25-0.50".

Next robust shortwave will be lifting to the north Wed evening with 
fairly strong cold front sweeping through the region 00-06z Thu. 
There will be some showers around Wed as PWATs remain elevated but 
not a washout. Best chance for a period of showers will likely be 
late in the day and especially during the evening as the front moves 
through. It will be rather mild Wed as temps will be rising into the 
50s by daybreak, and 925 mb temps up to 10-12C. Probably not much 
sunshine but if we do get a little sun, potential for highs to reach 
into the lower 60s Wed.

Wednesday night into Sunday...

After frontal passage, expect clearing skies and it will become 
blustery and turning sharply cooler late Wed night into Thu as 
strong cold advection develops. Temps will fall from the 50s Wed 
evening into the 30s and low 40s by daybreak Thu with only minor 
recovery during the day Thu. Mostly dry Thu but can't rule out a few 
flurries in western MA as a shortwave and colder temps aloft 
approaches from the west. Then windy and cold Fri into Sat with 
temps several degrees below normal. Fri will be the windier day as 
GFS soundings support gusts over 40 mph which is supported by 
increasing NBM probs of 40+ mph, then less wind Sat as gradient 
relaxes somewhat. There will be a risk of a few flurries or snow 
showers Fri as upper trough axis and increased moisture moves 
through, with more sunshine on Sat. Still looks mostly dry and 
seasonably cool Sunday but moisture may be returning in developing 
warm advection pattern as high pres moves offshore. Global ensembles 
do show an increase in PoPs for measurable rainfall.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
Forecaster Confidence Levels...

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

00z TAF Update:


Tonight: High confidence.

VFR with pockets of MVFR in areas of rain. Radar trends have
been downward over the last hour, so opted to end VCSH for most
TAF sites except the Cape and Islands. Light SW winds turn light
NW after 02z.

Monday: High confidence. 

VFR. WNW winds 10-15 kt, gusts to low 20s kt range but will
begin to decrease late in the day. 

Monday Night: High confidence.

VFR, increasing covg of mid/high clouds after 06z. WNW/W winds
5-10 kt early continue to decrease but then shift to SW and
increase to 5-10 kt after 06z.

KBOS Terminal...High confidence in TAF.

KBDL Terminal...High confidence in TAF.

Outlook /Tuesday through Friday/... 

Monday Night: VFR. 

Tuesday: Mainly VFR, with local MVFR possible. Breezy. Chance
RA.

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

Wednesday: MVFR/IFR conditions possible. Chance SHRA.

Wednesday Night: Mainly VFR, with local IFR possible. Breezy.
Chance SHRA.

Thanksgiving Day: VFR. Windy with areas of gusts up to 30 kt.

&&

.MARINE...
Forecaster Confidence Levels...

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

Through Monday Night: High confidence.

SW to W winds and seas remain below SCA criterion through the rest 
of the afternoon into early tonight. Outside chance at a sprinkle or 
flurry early tonight but not enough to reduce visibility.

Added small craft advisories for the southern waters starting after 
midnight into the first part of Monday as NW winds develop overnight 
and become gusty in the 25-30 kt range. Seas increase into the 3-6 
ft range, higher on the southern outer waters Mon. Winds and seas 
then begin to decrease early Mon night, with winds becoming 
southerly around 10-15 kt by Tue daybreak.

Outlook /Tuesday through Friday/... 

Monday Night: Winds less than 25 kt. 

Tuesday: Winds less than 25 kt. Chance of rain. 

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

Wednesday: Winds less than 25 kt. Areas of seas approaching
5 ft. Chance of rain showers. 

Wednesday Night: Low risk for Small Craft Advisory winds with
gusts up to 30 kt. Areas of seas approaching 5 ft. Chance of
rain showers. 

Thanksgiving Day: Strong winds with gusts up to 35 kt. Areas of
rough seas.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory from midnight tonight to 1 PM EST Monday 
     for ANZ232>235-237-254>256.

&&

$$

SYNOPSIS...KJC/Loconto
NEAR TERM...Loconto
SHORT TERM...Loconto
LONG TERM...KJC
AVIATION...KJC/KP
MARINE...KJC/Loconto