Walnut Hill weather by month
What a typical year looks like in Walnut Hill, Illinois: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at MT VERNON 3 NE, 21 km from Walnut Hill; records cover 1895–2026.
The year at a glance
- Precipitation a year
- 45 in1142 mm
- Snow a year
- 10 in26 cm
- Last spring freeze
- Apr 10
- First fall freeze
- Oct 18
- Heating degree days
- 5,000
- Cooling degree days
- 1,190
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are 2°−17° (heating, 99%) and 95°35° (cooling, 1%).
Month by month
Walnut Hill in January
Highs average 39°4° and lows 22°−6°, with 2.6 in66 mm of precipitation and 3 in8 cm of snow in a typical January.
- Record high
- 75°24° (1943)
- Record low
- −21°−29° (1994)
- Heating degree days
- 1082
- Cooling degree days
- 0
Walnut Hill in February
Highs average 44°6° and lows 25°−4°, with 2.6 in67 mm of precipitation and 3 in8 cm of snow in a typical February.
- Record high
- 79°26° (1972)
- Record low
- −22°−30° (1899)
- Heating degree days
- 860
- Cooling degree days
- 0
Walnut Hill in March
Highs average 54°12° and lows 34°1°, with 4 in102 mm of precipitation and 1 in2.5 cm of snow in a typical March.
- Record high
- 92°33° (1907)
- Record low
- −10°−23° (1978)
- Heating degree days
- 663
- Cooling degree days
- 2
Walnut Hill in April
Highs average 65°18° and lows 44°7°, with 5 in126 mm of precipitation in a typical April.
- Record high
- 91°33° (1901)
- Record low
- 17°−8° (1923)
- Heating degree days
- 331
- Cooling degree days
- 16
Walnut Hill in May
Highs average 74°23° and lows 55°13°, with 5.1 in129 mm of precipitation in a typical May.
- Record high
- 99°37° (1911)
- Record low
- 29°−2° (1903)
- Heating degree days
- 111
- Cooling degree days
- 92
Walnut Hill in June
Highs average 82°28° and lows 64°18°, with 4.8 in123 mm of precipitation in a typical June.
- Record high
- 105°41° (1914)
- Record low
- 36°2° (1924)
- Heating degree days
- 10
- Cooling degree days
- 251
Walnut Hill in July
Highs average 86°30° and lows 67°20°, with 3.8 in96 mm of precipitation in a typical July.
- Record high
- 114°46° (1936)
- Record low
- 46°8° (1947)
- Heating degree days
- 1
- Cooling degree days
- 357
Walnut Hill in August
Highs average 85°29° and lows 65°18°, with 3.3 in85 mm of precipitation in a typical August.
- Record high
- 111°44° (1936)
- Record low
- 42°6° (1986)
- Heating degree days
- 3
- Cooling degree days
- 306
Walnut Hill in September
Highs average 79°26° and lows 57°14°, with 3.4 in86 mm of precipitation in a typical September.
- Record high
- 105°41° (1939)
- Record low
- 23°−5° (1899)
- Heating degree days
- 60
- Cooling degree days
- 139
Walnut Hill in OctoberThis month
Highs average 68°20° and lows 45°7°, with 3.5 in90 mm of precipitation and 0.2 in0.5 cm of snow in a typical October.
- Record high
- 96°36° (1938)
- Record low
- 18°−8° (1981)
- Heating degree days
- 301
- Cooling degree days
- 25
Walnut Hill in November
Highs average 54°12° and lows 34°1°, with 4 in101 mm of precipitation and 0.4 in1 cm of snow in a typical November.
- Record high
- 86°30° (1938)
- Record low
- −5°−21° (1929)
- Heating degree days
- 633
- Cooling degree days
- 2
Walnut Hill in December
Highs average 43°6° and lows 26°−3°, with 2.9 in73 mm of precipitation and 2.5 in6.4 cm of snow in a typical December.
- Record high
- 78°26° (1970)
- Record low
- −19°−28° (1989)
- Heating degree days
- 945
- Cooling degree days
- 0