Grimes weather by month
What a typical year looks like in Grimes, Iowa: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at Des Moines International Airport, 20 km from Grimes; records cover 1878–2026.
The year at a glance
- Precipitation a year
- 36.6 in928 mm
- Snow a year
- 37 in93 cm
- Last spring freeze
- Apr 17
- First fall freeze
- Oct 15
- Heating degree days
- 6,178
- Cooling degree days
- 1,071
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are −6°−21° (heating, 99%) and 95°35° (cooling, 1%).
Month by month
Grimes in January
Highs average 31°−1° and lows 14°−10°, with 1.1 in27 mm of precipitation and 9 in24 cm of snow in a typical January.
- Record high
- 67°19° (2003)
- Record low
- −30°−34° (1884)
- Heating degree days
- 1322
- Cooling degree days
- 0
Grimes in February
Highs average 36°2° and lows 18°−8°, with 1.3 in34 mm of precipitation and 10 in26 cm of snow in a typical February.
- Record high
- 78°26° (1930)
- Record low
- −26°−32° (1905)
- Heating degree days
- 1068
- Cooling degree days
- 0
Grimes in March
Highs average 49°10° and lows 30°−1°, with 2.2 in55 mm of precipitation and 4 in11 cm of snow in a typical March.
- Record high
- 91°33° (1986)
- Record low
- −22°−30° (1962)
- Heating degree days
- 796
- Cooling degree days
- 2
Grimes in April
Highs average 62°17° and lows 41°5°, with 4 in102 mm of precipitation and 1.2 in3 cm of snow in a typical April.
- Record high
- 93°34° (1980)
- Record low
- 9°−13° (1975)
- Heating degree days
- 421
- Cooling degree days
- 10
Grimes in May
Highs average 72°22° and lows 52°11°, with 5.2 in133 mm of precipitation and 0.2 in0.5 cm of snow in a typical May.
- Record high
- 105°41° (1934)
- Record low
- 26°−3° (1907)
- Heating degree days
- 153
- Cooling degree days
- 71
Grimes in June
Highs average 82°28° and lows 62°17°, with 5.3 in134 mm of precipitation in a typical June.
- Record high
- 103°39° (1933)
- Record low
- 37°3° (1889)
- Heating degree days
- 15
- Cooling degree days
- 230
Grimes in July
Highs average 86°30° and lows 66°19°, with 3.8 in97 mm of precipitation in a typical July.
- Record high
- 110°43° (1936)
- Record low
- 47°8° (1971)
- Heating degree days
- 1
- Cooling degree days
- 342
Grimes in August
Highs average 84°29° and lows 64°18°, with 4.2 in106 mm of precipitation in a typical August.
- Record high
- 110°43° (1918)
- Record low
- 40°4° (1891)
- Heating degree days
- 4
- Cooling degree days
- 280
Grimes in September
Highs average 77°25° and lows 55°13°, with 3.2 in81 mm of precipitation in a typical September.
- Record high
- 101°38° (1939)
- Record low
- 26°−3° (1899)
- Heating degree days
- 86
- Cooling degree days
- 120
Grimes in OctoberThis month
Highs average 63°17° and lows 43°6°, with 2.8 in71 mm of precipitation and 0.5 in1.3 cm of snow in a typical October.
- Record high
- 95°35° (1963)
- Record low
- 7°−14° (1925)
- Heating degree days
- 383
- Cooling degree days
- 16
Grimes in November
Highs average 48°9° and lows 30°−1°, with 1.9 in49 mm of precipitation and 2.7 in6.9 cm of snow in a typical November.
- Record high
- 82°28° (1938)
- Record low
- −10°−23° (1891)
- Heating degree days
- 773
- Cooling degree days
- 0
Grimes in December
Highs average 36°2° and lows 20°−7°, with 1.6 in40 mm of precipitation and 8 in20 cm of snow in a typical December.
- Record high
- 74°23° (2021)
- Record low
- −22°−30° (1989)
- Heating degree days
- 1156
- Cooling degree days
- 0