Weather for Groton, Connecticut
Current Weather
Five Day Weather Forecast
Sun
H: 26°F
L: 8°F
Mon
H: 33°F
L: 14°F
Tue
H: 34°F
L: 15°F
Wed
H: 31°F
L: 15°F
Thu
H: 28°F
L: 11°F
Air Quality
Nitrogen Dioxide: 5.85 μg/m3
Sulphur Dioxide: 1.75 μg/m3
Ozone: 67 μg/m3
Astronomical
Sun Transit: 12:01 AM
Sunset: 5:05 PM
Daylight: 10 hrs 5 mins
Moon Transit: 12:00 AM
Moonset: 7:01 AM
Moon Phase: Full
Moon Illumination: 99.9%
Best Times for Fishing or Hunting
Major Periods
12:00 AM - 12:00 AM1:51 PM - 4:21 PM
Minor Periods
4:24 PM - 5:54 PM6:31 AM - 8:01 AM
Action Rating: 4 out of 5
Cold Weather Advisory issued January 31 at 1:10PM EST until February 1 at 10:00AM EST by NWS Upton NY
Effective: Sat January 31, 2026, 1:10 PM
Expires: Sun February 1, 2026, 2:00 AM
* WHAT...Very cold wind chills as low as 10 to 15 below. * WHERE...Portions of southern Connecticut, northeast New Jersey, and southeast New York. * WHEN...Until 10 AM EST Sunday. * IMPACTS...The cold wind chills could result in hypothermia if precautions are not taken.
Use caution while traveling outside. Wear appropriate clothing, a hat, and gloves.
Cold Weather Advisory issued February 1 at 1:14AM EST until February 1 at 10:00AM EST by NWS Upton NY
Effective: Sun February 1, 2026, 1:14 AM
Expires: Sun February 1, 2026, 10:00 AM
* WHAT...Very cold wind chills as low as 10 to 15 below. * WHERE...Portions of southern Connecticut, northeast New Jersey, and southeast New York. * WHEN...Until 10 AM EST this morning. * IMPACTS...The cold wind chills could result in hypothermia if precautions are not taken.
Use caution while traveling outside. Wear appropriate clothing, a hat, and gloves.
Cold Weather Advisory issued January 31 at 12:19PM EST until February 1 at 10:00AM EST by NWS Boston/Norton MA
Effective: Sat January 31, 2026, 12:19 PM
Expires: Sun February 1, 2026, 1:30 AM
* WHAT...Very cold wind chills as low as 10 to 15 below expected. * WHERE...Franklin County, Hampshire County, Hampden County, Hartford CT, Tolland CT, and Windham CT. * WHEN...From 10 PM this evening to 10 AM EST Sunday. * IMPACTS...The cold wind chills as low as 15 below zero could result in hypothermia if precautions are not taken.
Use caution while traveling outside. Wear appropriate clothing, a hat, and gloves.
Coastal Flood Statement issued January 31 at 3:32PM EST until February 1 at 2:00PM EST by NWS Upton NY
Effective: Sat January 31, 2026, 3:32 PM
Expires: Sun February 1, 2026, 2:00 PM
* WHAT...Up to one half foot of inundation above ground level expected in vulnerable areas near the waterfront and shoreline. * WHERE...In Connecticut, Southern New Haven County. In New York, Bronx, Northwest Suffolk, Northeast Suffolk, Northern Queens and Northern Nassau Counties. * WHEN...From Sunday morning through Sunday afternoon. * IMPACTS...Brief minor flooding of the more vulnerable locations near the waterfront and shoreline. * ADDITIONAL DETAILS...Additional minor coastal flooding is possible with high tide cycles late Sunday through early Monday.
Do not drive through flooded roadways.
Coastal Flood Statement issued February 1 at 1:14AM EST until February 1 at 2:00PM EST by NWS Upton NY
Effective: Sun February 1, 2026, 1:14 AM
Expires: Sun February 1, 2026, 10:00 AM
* WHAT...Up to one half foot of inundation above ground level expected in vulnerable areas near the waterfront and shoreline. * WHERE...In Connecticut, Southern New Haven County. In New York, Bronx, Northwest Suffolk, Northeast Suffolk, Northern Queens and Northern Nassau Counties. * WHEN...From 7 AM EST this morning through this afternoon. * IMPACTS...Brief minor flooding of the more vulnerable locations near the waterfront and shoreline. * ADDITIONAL DETAILS...Additional minor coastal flooding is possible with high tide cycles late today through early Monday.
Do not drive through flooded roadways.
Weather Forecast
Air Quality
Nitrogen Dioxide: 7.38 μg/m3
Sulphur Dioxide: 1.85 μg/m3
Ozone: 71.04 μg/m3
Astronomical
Sun Transit: 12:01 AM
Sunset: 5:05 PM
Daylight: 10 hrs 5 mins
Moon Transit: 12:00 AM
Moonset: 7:01 AM
Moon Phase: Full
Moon Illumination: 99.9%
Best Times for Fishing or Hunting
Major Periods
12:00 AM - 12:00 AM1:51 PM - 4:21 PM
Minor Periods
4:24 PM - 5:54 PM6:31 AM - 8:01 AM
Action Rating: 4 out of 5
Weather Forecast
Air Quality
Nitrogen Dioxide: 6.87 μg/m3
Sulphur Dioxide: 2.07 μg/m3
Ozone: 80.52 μg/m3
Astronomical
Sun Transit: 12:02 AM
Sunset: 5:06 PM
Daylight: 10 hrs 7 mins
Moon Transit: 12:20 AM
Moonset: 7:32 AM
Moon Phase: Full
Moon Illumination: 99.4%
Best Times for Fishing or Hunting
Major Periods
12:00 AM - 12:00 AM2:43 PM - 5:13 PM
Minor Periods
5:39 PM - 7:09 PM7:02 AM - 8:32 AM
Action Rating: 5 out of 5
Weather Forecast
Air Quality
Nitrogen Dioxide: 10.41 μg/m3
Sulphur Dioxide: 2.67 μg/m3
Ozone: 72.64 μg/m3
Astronomical
Sun Transit: 12:02 AM
Sunset: 5:07 PM
Daylight: 10 hrs 10 mins
Moon Transit: 1:10 AM
Moonset: 7:57 AM
Moon Phase: Full
Moon Illumination: 96.3%
Best Times for Fishing or Hunting
Major Periods
12:40 AM - 3:10 AM3:31 PM - 6:01 PM
Minor Periods
6:50 PM - 8:20 PM7:27 AM - 8:57 AM
Action Rating: 4 out of 5
Weather Forecast
Air Quality
Nitrogen Dioxide: 23.47 μg/m3
Sulphur Dioxide: 4.57 μg/m3
Ozone: 49.72 μg/m3
Astronomical
Sun Transit: 12:02 AM
Sunset: 5:08 PM
Daylight: 10 hrs 12 mins
Moon Transit: 1:56 AM
Moonset: 8:20 AM
Moon Phase: Full
Moon Illumination: 90.9%
Best Times for Fishing or Hunting
Major Periods
1:26 AM - 3:56 AM4:16 PM - 6:46 PM
Minor Periods
7:59 PM - 9:29 PM7:50 AM - 9:20 AM
Action Rating: 3 out of 5
Weather Forecast
Air Quality
Nitrogen Dioxide: 5.74 μg/m3
Sulphur Dioxide: 1.7 μg/m3
Ozone: 67.77 μg/m3
Astronomical
Sun Transit: 12:02 AM
Sunset: 5:10 PM
Daylight: 10 hrs 14 mins
Moon Transit: 2:39 AM
Moonset: 8:40 AM
Moon Phase: Waning Gibbous
Moon Illumination: 83.4%
Best Times for Fishing or Hunting
Major Periods
2:09 AM - 4:39 AM4:58 PM - 7:28 PM
Minor Periods
9:04 PM - 10:34 PM8:10 AM - 9:40 AM
Action Rating: 3 out of 5