Rockwell weather by month
What a typical year looks like in Rockwell, Iowa: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at Mason City Municipal Airport, 22 km from Rockwell; records cover 1948–2026.
The year at a glance
- Precipitation a year
- 36.3 in921 mm
- Snow a year
- 44 in113 cm
- Last spring freeze
- May 2
- First fall freeze
- Sep 29
- Heating degree days
- 7,646
- Cooling degree days
- 602
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are −14°−26° (heating, 99%) and 93°34° (cooling, 1%).
Month by month
Rockwell in January
Highs average 24°−4° and lows 7°−14°, with 0.89 in23 mm of precipitation and 11 in29 cm of snow in a typical January.
- Record high
- 62°17° (2002)
- Record low
- −31°−35° (2009)
- Heating degree days
- 1528
- Cooling degree days
- 0
Rockwell in February
Highs average 29°−2° and lows 11°−11°, with 1.2 in31 mm of precipitation and 10 in25 cm of snow in a typical February.
- Record high
- 73°23° (2024)
- Record low
- −32°−36° (1996)
- Heating degree days
- 1261
- Cooling degree days
- 0
Rockwell in March
Highs average 42°6° and lows 24°−5°, with 2.3 in58 mm of precipitation and 7 in18 cm of snow in a typical March.
- Record high
- 84°29° (1986)
- Record low
- −28°−33° (1962)
- Heating degree days
- 997
- Cooling degree days
- 0
Rockwell in April
Highs average 58°14° and lows 35°1°, with 4.2 in105 mm of precipitation and 3 in8 cm of snow in a typical April.
- Record high
- 93°34° (1980)
- Record low
- 6°−14° (1982)
- Heating degree days
- 573
- Cooling degree days
- 3
Rockwell in May
Highs average 70°21° and lows 47°8°, with 5.2 in131 mm of precipitation and 0.3 in0.8 cm of snow in a typical May.
- Record high
- 99°37° (2013)
- Record low
- 22°−6° (2005)
- Heating degree days
- 246
- Cooling degree days
- 35
Rockwell in June
Highs average 80°26° and lows 57°14°, with 5.4 in137 mm of precipitation in a typical June.
- Record high
- 103°39° (1985)
- Record low
- 36°2° (1993)
- Heating degree days
- 39
- Cooling degree days
- 142
Rockwell in July
Highs average 83°28° and lows 61°16°, with 4.4 in113 mm of precipitation in a typical July.
- Record high
- 104°40° (1980)
- Record low
- 42°6° (1967)
- Heating degree days
- 10
- Cooling degree days
- 212
Rockwell in August
Highs average 80°27° and lows 58°14°, with 3.8 in96 mm of precipitation in a typical August.
- Record high
- 101°38° (1965)
- Record low
- 35°2° (1950)
- Heating degree days
- 26
- Cooling degree days
- 147
Rockwell in September
Highs average 74°23° and lows 49°9°, with 3.5 in88 mm of precipitation in a typical September.
- Record high
- 99°37° (2013)
- Record low
- 24°−4° (1949)
- Heating degree days
- 164
- Cooling degree days
- 57
Rockwell in OctoberThis month
Highs average 60°16° and lows 37°3°, with 2.5 in64 mm of precipitation and 0.4 in1 cm of snow in a typical October.
- Record high
- 95°35° (1963)
- Record low
- 12°−11° (1967)
- Heating degree days
- 525
- Cooling degree days
- 6
Rockwell in November
Highs average 44°6° and lows 24°−4°, with 1.7 in42 mm of precipitation and 3 in8 cm of snow in a typical November.
- Record high
- 79°26° (2006)
- Record low
- −16°−27° (1977)
- Heating degree days
- 932
- Cooling degree days
- 0
Rockwell in December
Highs average 30°−1° and lows 14°−10°, with 1.3 in33 mm of precipitation and 9 in24 cm of snow in a typical December.
- Record high
- 69°21° (2021)
- Record low
- −26°−32° (1950)
- Heating degree days
- 1345
- Cooling degree days
- 0