Norwalk weather by month
What a typical year looks like in Norwalk, Connecticut: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at WESTCHESTER CO AP, 24 km from Norwalk; records cover 1948–2026.
The year at a glance
- Precipitation a year
- 47.8 in1213 mm
- Snow a year
- Rare
- Last spring freeze
- Apr 11
- First fall freeze
- Oct 30
- Heating degree days
- 5,493
- Cooling degree days
- 787
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 92°33° (cooling, 1%).
Month by month
Norwalk in January
Highs average 37°3° and lows 22°−5°, with 3.2 in81 mm of precipitation in a typical January.
- Record high
- 70°21° (2007)
- Record low
- −10°−23° (1961)
- Heating degree days
- 1090
- Cooling degree days
- 0
Norwalk in February
Highs average 40°5° and lows 24°−5°, with 2.5 in64 mm of precipitation in a typical February.
- Record high
- 77°25° (2018)
- Record low
- −10°−23° (1979)
- Heating degree days
- 927
- Cooling degree days
- 0
Norwalk in March
Highs average 48°9° and lows 31°−1°, with 4.1 in104 mm of precipitation in a typical March.
- Record high
- 82°28° (1990)
- Record low
- −6°−21° (1967)
- Heating degree days
- 805
- Cooling degree days
- 0
Norwalk in April
Highs average 59°15° and lows 40°5°, with 4.2 in107 mm of precipitation in a typical April.
- Record high
- 92°33° (2002)
- Record low
- 16°−9° (1982)
- Heating degree days
- 465
- Cooling degree days
- 4
Norwalk in May
Highs average 69°21° and lows 50°10°, with 3.9 in100 mm of precipitation in a typical May.
- Record high
- 96°36° (1969)
- Record low
- 32°0° (1966)
- Heating degree days
- 201
- Cooling degree days
- 30
Norwalk in June
Highs average 78°26° and lows 59°15°, with 4.3 in108 mm of precipitation in a typical June.
- Record high
- 98°37° (1952)
- Record low
- 39°4° (1980)
- Heating degree days
- 35
- Cooling degree days
- 142
Norwalk in July
Highs average 83°28° and lows 65°18°, with 4.1 in103 mm of precipitation in a typical July.
- Record high
- 102°39° (1966)
- Record low
- 46°8° (1979)
- Heating degree days
- 2
- Cooling degree days
- 282
Norwalk in August
Highs average 81°27° and lows 64°18°, with 4.4 in111 mm of precipitation in a typical August.
- Record high
- 101°38° (2001)
- Record low
- 41°5° (1982)
- Heating degree days
- 4
- Cooling degree days
- 233
Norwalk in September
Highs average 74°23° and lows 57°14°, with 4.9 in125 mm of precipitation in a typical September.
- Record high
- 100°38° (1953)
- Record low
- 32°0° (2004)
- Heating degree days
- 74
- Cooling degree days
- 88
Norwalk in OctoberThis month
Highs average 63°17° and lows 46°8°, with 4.3 in110 mm of precipitation in a typical October.
- Record high
- 90°32° (2019)
- Record low
- 24°−4° (1972)
- Heating degree days
- 341
- Cooling degree days
- 8
Norwalk in November
Highs average 52°11° and lows 36°2°, with 3.6 in92 mm of precipitation in a typical November.
- Record high
- 79°26° (2024)
- Record low
- 11°−12° (2018)
- Heating degree days
- 624
- Cooling degree days
- 0
Norwalk in December
Highs average 42°6° and lows 28°−2°, with 4.2 in106 mm of precipitation in a typical December.
- Record high
- 75°24° (1998)
- Record low
- −5°−21° (1980)
- Heating degree days
- 925
- Cooling degree days
- 0