Old Res Weather

Lexington, Massachusetts, USA

35°F

2/16/2025 7:17pm

Lexington Conditions: Light rain, Mostly cloudy
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 210713
AFDBOX

Area Forecast Discussion
National Weather Service Boston/Norton MA
313 AM EDT Sun Jun 21 2026

.WHAT HAS CHANGED...
Forecast remains on track.

&&

.KEY MESSAGES...

- While the risk for severe weather remains low, scattered
  diurnal showers and thunderstorms are possible today.
  Otherwise, not as gusty.

- Periods of heavy rain possible Monday into early Tuesday.
  Drier air with seasonable temperatures expected midweek.
  Chances for rain return for the end of next week.

&&

.DISCUSSION...
KEY MESSAGE 1...While the risk for severe weather remains low,
scattered diurnal showers and thunderstorms are possible 
today. Otherwise, not as gusty.

Not much change to the overall synoptic pattern today. We will
still have a mid level trough over eastern Canada as well as
another sheared shortwave this afternoon and evening. Projected
CAPE values still between 500-1,000 J/kg. Almost no vertical
shear to speak of, so not overly concerned about the prospects
for severe weather. This should be enough for another round of
scattered afternoon showers and thunderstorms. The greatest risk
is towards northeast MA. 

Tricky forecast with respect to coastal winds. Westerly winds do
look to be just strong enough to prevent the seabreeze from
moving too far inland. A seabreeze front could provide a greater
focus for showers and thunderstorms. At this time, expecting
only local seabreezes rather than the typical front which pushes
inland to the I-95 corridor. This will need to be monitored
through today.

KEY MESSAGE 2...Periods of heavy rain possible Monday into early
Tuesday. Drier air with seasonable temperatures expected
midweek. Chances for rain return for the end of next week.

A low pressure system is expected to bring a widespread, soaking
rainfall to southern New England from Monday afternoon into
Tuesday. The probability for 1+ inch of storm total rainfall was
still between 70 to 80 percent across most of our region. The 
probability for 2+ inches of rainfall remained about 30 to 50 
percent, greatest across western MA and CT. Groundwater and
streamflow observations were less than the 10th percentile. 
This indicates we have plenty of room to accommodate this 
rainfall. Perhaps a different story in the urban areas. While 
there could be thunderstorms, we do not anticipate these to be 
strong enough to result in flooding. This will still need to be 
monitored. We should dry out from west to east as a low pressure
along the south coast of New England moves offshore.

High pressure builds into the region behind this system, 
providing drier with and seasonable temperatures for the middle 
of the week. Chances for rain begin to increase once again by 
the end of the work week.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
Forecaster Confidence Levels...

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

Today: High confidence.

VFR. Relatively light west winds could lead to afternoon 
seabreezes. Another risk for afternoon -SHRA and -TSRA.

Tonight: High Confidence.

VFR with light and variable winds.

Monday: High confidence.

VFR for most of the day. MVFR arrives from west to east during
the afternoon. Relatively light winds continue.

KBOS Terminal...High confidence in TAF. Have some concern for a
seabreeze, but not enough to include it in the TAF just yet.
Most likely time for a seabreeze would be between 18-00Z.
 
KBDL Terminal...High confidence in TAF.

Outlook /Monday Night through Thursday/...

Monday Night: Mainly MVFR, with areas IFR possible. Breezy.
SHRA, slight chance TSRA.

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

Tuesday Night through Thursday: VFR. 

&&

.MARINE...
Forecaster Confidence Levels...

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

Small Craft Advisories will be allowed to end early this morning.
Risk for scattered showers and isolated thunderstorms this
afternoon and evening, especially near the east coast. Any 
showers and thunderstorms should diminish after sunset.

Outlook /Monday Night through Thursday/...

Monday Night: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Areas of seas approaching 5 ft. Rain
showers, slight chance of thunderstorms. 

Tuesday: Winds less than 25 kt. Seas up to 5 ft. Chance of rain
showers, slight chance of thunderstorms. 

Tuesday Night: Winds less than 25 kt. Seas up to 5 ft. Slight
chance of rain showers. 

Wednesday through Wednesday Night: Winds less than 25 kt. Seas
locally approaching 5 ft. 

Thursday: Winds less than 25 kt. 

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory until 4 AM EDT early this morning for 
     ANZ255.

&&

$$

DISCUSSION...Belk
AVIATION...Belk
MARINE...Belk