Spillville weather by month
What a typical year looks like in Spillville, Iowa: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at Decorah, 17 km from Spillville; records cover 1893–2026.
The year at a glance
- Precipitation a year
- 37.6 in955 mm
- Snow a year
- 38 in95 cm
- Last spring freeze
- May 9
- First fall freeze
- Oct 2
- Heating degree days
- 6,793
- Cooling degree days
- 828
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are −15°−26° (heating, 99%) and 93°34° (cooling, 1%).
Month by month
Spillville in January
Highs average 28°−2° and lows 10°−12°, with 1 in26 mm of precipitation and 10 in26 cm of snow in a typical January.
- Record high
- 62°17° (2025)
- Record low
- −43°−42° (1951)
- Heating degree days
- 1424
- Cooling degree days
- 0
Spillville in February
Highs average 33°0° and lows 14°−10°, with 1.1 in28 mm of precipitation and 8 in21 cm of snow in a typical February.
- Record high
- 74°23° (2024)
- Record low
- −41° (1996)
- Heating degree days
- 1165
- Cooling degree days
- 0
Spillville in March
Highs average 46°8° and lows 26°−3°, with 2.1 in52 mm of precipitation and 6 in14 cm of snow in a typical March.
- Record high
- 85°29° (2025)
- Record low
- −33°−36° (1962)
- Heating degree days
- 898
- Cooling degree days
- 1
Spillville in April
Highs average 61°16° and lows 37°3°, with 4 in100 mm of precipitation and 1.7 in4.3 cm of snow in a typical April.
- Record high
- 93°34° (1910)
- Record low
- 5°−15° (1982)
- Heating degree days
- 478
- Cooling degree days
- 7
Spillville in May
Highs average 73°23° and lows 48°9°, with 4.9 in125 mm of precipitation in a typical May.
- Record high
- 102°39° (1934)
- Record low
- 20°−7° (1908)
- Heating degree days
- 193
- Cooling degree days
- 52
Spillville in June
Highs average 81°27° and lows 59°15°, with 6.1 in156 mm of precipitation in a typical June.
- Record high
- 105°41° (1910)
- Record low
- 29°−2° (1897)
- Heating degree days
- 28
- Cooling degree days
- 178
Spillville in July
Highs average 84°29° and lows 63°17°, with 4.4 in112 mm of precipitation in a typical July.
- Record high
- 111°44° (1936)
- Record low
- 38°3° (1926)
- Heating degree days
- 4
- Cooling degree days
- 268
Spillville in August
Highs average 83°28° and lows 61°16°, with 4.4 in112 mm of precipitation in a typical August.
- Record high
- 105°41° (2023)
- Record low
- 32°0° (1915)
- Heating degree days
- 11
- Cooling degree days
- 218
Spillville in September
Highs average 76°25° and lows 52°11°, with 3.6 in91 mm of precipitation in a typical September.
- Record high
- 100°38° (1913)
- Record low
- 18°−8° (1899)
- Heating degree days
- 111
- Cooling degree days
- 92
Spillville in OctoberThis month
Highs average 63°17° and lows 40°5°, with 2.7 in68 mm of precipitation in a typical October.
- Record high
- 94°34° (1963)
- Record low
- −7°−22° (1925)
- Heating degree days
- 421
- Cooling degree days
- 12
Spillville in November
Highs average 47°8° and lows 28°−2°, with 2.1 in52 mm of precipitation and 2.4 in6.1 cm of snow in a typical November.
- Record high
- 79°26° (1893)
- Record low
- −16°−27° (1930)
- Heating degree days
- 825
- Cooling degree days
- 0
Spillville in December
Highs average 33°0° and lows 17°−8°, with 1.3 in33 mm of precipitation and 9 in23 cm of snow in a typical December.
- Record high
- 69°21° (2021)
- Record low
- −36°−38° (1950)
- Heating degree days
- 1235
- Cooling degree days
- 0