Niantic weather by month
What a typical year looks like in Niantic, Connecticut: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at Groton New London Airport, 13 km from Niantic; records cover 1999–2026.
The year at a glance
- Precipitation a year
- 39.3 in998 mm
- Snow a year
- Rare
- Last spring freeze
- Apr 22
- First fall freeze
- Oct 27
- Heating degree days
- 5,522
- Cooling degree days
- 608
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are 7°−14° (heating, 99%) and 88°31° (cooling, 1%).
Month by month
Niantic in January
Highs average 38°3° and lows 23°−5°, with 2.7 in68 mm of precipitation in a typical January.
- Record high
- 66°19° (2020)
- Record low
- −7°−22° (2009)
- Heating degree days
- 1060
- Cooling degree days
- 0
Niantic in February
Highs average 40°5° and lows 25°−4°, with 2.2 in56 mm of precipitation in a typical February.
- Record high
- 71°22° (2023)
- Record low
- −8°−22° (2016)
- Heating degree days
- 913
- Cooling degree days
- 0
Niantic in March
Highs average 47°8° and lows 31°−1°, with 3.8 in97 mm of precipitation in a typical March.
- Record high
- 74°23° (2011)
- Record low
- 4°−16° (2015)
- Heating degree days
- 817
- Cooling degree days
- 0
Niantic in April
Highs average 56°13° and lows 39°4°, with 3.6 in91 mm of precipitation in a typical April.
- Record high
- 86°30° (2009)
- Record low
- 22°−6° (2019)
- Heating degree days
- 521
- Cooling degree days
- 1
Niantic in May
Highs average 65°18° and lows 49°9°, with 3.3 in84 mm of precipitation in a typical May.
- Record high
- 93°34° (2022)
- Record low
- 30°−1° (2008)
- Heating degree days
- 261
- Cooling degree days
- 7
Niantic in June
Highs average 74°23° and lows 58°15°, with 3.3 in84 mm of precipitation in a typical June.
- Record high
- 93°34° (2025)
- Record low
- 40°4° (2001)
- Heating degree days
- 52
- Cooling degree days
- 82
Niantic in July
Highs average 80°27° and lows 65°18°, with 3.2 in82 mm of precipitation in a typical July.
- Record high
- 101°38° (2010)
- Record low
- 50°10° (2002)
- Heating degree days
- 2
- Cooling degree days
- 228
Niantic in August
Highs average 79°26° and lows 64°18°, with 3.3 in84 mm of precipitation in a typical August.
- Record high
- 93°34° (2016)
- Record low
- 47°8° (2000)
- Heating degree days
- 5
- Cooling degree days
- 206
Niantic in September
Highs average 74°23° and lows 57°14°, with 3.8 in97 mm of precipitation in a typical September.
- Record high
- 90°32° (2018)
- Record low
- 36°2° (2000)
- Heating degree days
- 71
- Cooling degree days
- 77
Niantic in OctoberThis month
Highs average 63°17° and lows 46°8°, with 3.7 in93 mm of precipitation in a typical October.
- Record high
- 87°31° (2019)
- Record low
- 24°−4° (2015)
- Heating degree days
- 336
- Cooling degree days
- 7
Niantic in November
Highs average 53°12° and lows 37°3°, with 3.2 in82 mm of precipitation in a typical November.
- Record high
- 79°26° (2022)
- Record low
- 12°−11° (2018)
- Heating degree days
- 599
- Cooling degree days
- 0
Niantic in December
Highs average 44°7° and lows 29°−2°, with 3.1 in80 mm of precipitation in a typical December.
- Record high
- 66°19° (2001)
- Record low
- 6°−14° (2004)
- Heating degree days
- 885
- Cooling degree days
- 0