Patterson weather by month
What a typical year looks like in Patterson, Iowa: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at Winterset 4n, 13 km from Patterson; records cover 1893–2026.
The year at a glance
- Precipitation a year
- 34.8 in884 mm
- Snow a year
- 31 in78 cm
- Last spring freeze
- Apr 24
- First fall freeze
- Oct 3
- Heating degree days
- 6,869
- Cooling degree days
- 738
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are −10°−23° (heating, 99%) and 94°34° (cooling, 1%).
Month by month
Patterson in January
Highs average 30°−1° and lows 10°−12°, with 0.78 in20 mm of precipitation and 7 in19 cm of snow in a typical January.
- Record high
- 67°19° (2002)
- Record low
- −34°−37° (1912)
- Heating degree days
- 1400
- Cooling degree days
- 0
Patterson in February
Highs average 35°2° and lows 13°−10°, with 1.3 in33 mm of precipitation and 8 in21 cm of snow in a typical February.
- Record high
- 79°26° (1930)
- Record low
- −31°−35° (1958)
- Heating degree days
- 1148
- Cooling degree days
- 0
Patterson in March
Highs average 48°9° and lows 25°−4°, with 2.1 in54 mm of precipitation and 5 in12 cm of snow in a typical March.
- Record high
- 92°33° (2026)
- Record low
- −35°−37° (1962)
- Heating degree days
- 893
- Cooling degree days
- 1
Patterson in April
Highs average 61°16° and lows 35°2°, with 3.6 in91 mm of precipitation and 0.8 in2 cm of snow in a typical April.
- Record high
- 93°34° (1910)
- Record low
- 10°−12° (1936)
- Heating degree days
- 515
- Cooling degree days
- 3
Patterson in May
Highs average 71°22° and lows 48°9°, with 5 in127 mm of precipitation and 0.1 in0.3 cm of snow in a typical May.
- Record high
- 105°41° (1934)
- Record low
- 24°−4° (1981)
- Heating degree days
- 213
- Cooling degree days
- 40
Patterson in June
Highs average 80°27° and lows 58°15°, with 4.6 in118 mm of precipitation in a typical June.
- Record high
- 105°41° (1934)
- Record low
- 34°1° (1969)
- Heating degree days
- 32
- Cooling degree days
- 156
Patterson in July
Highs average 84°29° and lows 62°17°, with 4.1 in104 mm of precipitation in a typical July.
- Record high
- 111°44° (1934)
- Record low
- 40°4° (1896)
- Heating degree days
- 6
- Cooling degree days
- 254
Patterson in August
Highs average 82°28° and lows 59°15°, with 3.6 in92 mm of precipitation in a typical August.
- Record high
- 112°44° (1934)
- Record low
- 37°3° (1915)
- Heating degree days
- 18
- Cooling degree days
- 199
Patterson in September
Highs average 76°24° and lows 51°10°, with 3.6 in91 mm of precipitation in a typical September.
- Record high
- 103°39° (1939)
- Record low
- 24°−4° (1899)
- Heating degree days
- 132
- Cooling degree days
- 75
Patterson in OctoberThis month
Highs average 63°17° and lows 38°3°, with 2.9 in73 mm of precipitation and 0.9 in2.3 cm of snow in a typical October.
- Record high
- 93°34° (1953)
- Record low
- 3°−16° (1925)
- Heating degree days
- 450
- Cooling degree days
- 10
Patterson in November
Highs average 48°9° and lows 26°−3°, with 2 in50 mm of precipitation and 2.7 in6.9 cm of snow in a typical November.
- Record high
- 82°28° (1938)
- Record low
- −8°−22° (1976)
- Heating degree days
- 838
- Cooling degree days
- 0
Patterson in December
Highs average 35°2° and lows 16°−9°, with 1.2 in31 mm of precipitation and 6 in15 cm of snow in a typical December.
- Record high
- 69°21° (1939)
- Record low
- −25°−32° (1989)
- Heating degree days
- 1224
- Cooling degree days
- 0