Normal weather by month
What a typical year looks like in Normal, Illinois: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at NORMAL 4NE, 5 km from Normal; records cover 1893–2026.
The year at a glance
- Precipitation a year
- 39.4 in1001 mm
- Snow a year
- 20 in51 cm
- Last spring freeze
- Apr 21
- First fall freeze
- Oct 14
- Heating degree days
- 6,022
- Cooling degree days
- 977
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are −5°−21° (heating, 99%) and 95°35° (cooling, 1%).
Month by month
Normal in January
Highs average 33°1° and lows 16°−9°, with 2.4 in62 mm of precipitation and 8 in19 cm of snow in a typical January.
- Record high
- 69°21° (1909)
- Record low
- −24°−31° (1894)
- Heating degree days
- 1255
- Cooling degree days
- 0
Normal in February
Highs average 38°3° and lows 19°−7°, with 2 in51 mm of precipitation and 6 in14 cm of snow in a typical February.
- Record high
- 76°24° (2024)
- Record low
- −24°−31° (1895)
- Heating degree days
- 1020
- Cooling degree days
- 0
Normal in March
Highs average 50°10° and lows 28°−2°, with 2.6 in66 mm of precipitation and 2.2 in5.6 cm of snow in a typical March.
- Record high
- 88°31° (1907)
- Record low
- −15°−26° (1943)
- Heating degree days
- 814
- Cooling degree days
- 2
Normal in April
Highs average 63°17° and lows 38°3°, with 3.7 in94 mm of precipitation and 0.5 in1.3 cm of snow in a typical April.
- Record high
- 95°35° (1896)
- Record low
- 5°−15° (2018)
- Heating degree days
- 448
- Cooling degree days
- 8
Normal in May
Highs average 74°23° and lows 50°10°, with 4.8 in122 mm of precipitation in a typical May.
- Record high
- 103°39° (1934)
- Record low
- 21°−6° (1966)
- Heating degree days
- 172
- Cooling degree days
- 76
Normal in June
Highs average 83°29° and lows 60°16°, with 4.1 in104 mm of precipitation in a typical June.
- Record high
- 106°41° (1934)
- Record low
- 31°−1° (1894)
- Heating degree days
- 20
- Cooling degree days
- 218
Normal in July
Highs average 86°30° and lows 63°17°, with 4.1 in105 mm of precipitation in a typical July.
- Record high
- 114°46° (1936)
- Record low
- 41°5° (1894)
- Heating degree days
- 3
- Cooling degree days
- 297
Normal in August
Highs average 84°29° and lows 61°16°, with 3.8 in97 mm of precipitation in a typical August.
- Record high
- 105°41° (1918)
- Record low
- 38°3° (1894)
- Heating degree days
- 8
- Cooling degree days
- 244
Normal in September
Highs average 79°26° and lows 53°12°, with 3.2 in82 mm of precipitation in a typical September.
- Record high
- 103°39° (1899)
- Record low
- 22°−6° (1899)
- Heating degree days
- 87
- Cooling degree days
- 114
Normal in OctoberThis month
Highs average 66°19° and lows 42°5°, with 3.5 in88 mm of precipitation in a typical October.
- Record high
- 93°34° (1897)
- Record low
- 9°−13° (1925)
- Heating degree days
- 368
- Cooling degree days
- 18
Normal in November
Highs average 50°10° and lows 31°−1°, with 2.8 in71 mm of precipitation and 0.8 in2 cm of snow in a typical November.
- Record high
- 82°28° (1915)
- Record low
- −7°−22° (1893)
- Heating degree days
- 737
- Cooling degree days
- 0
Normal in December
Highs average 38°3° and lows 21°−6°, with 2.3 in58 mm of precipitation and 4 in9 cm of snow in a typical December.
- Record high
- 72°22° (2012)
- Record low
- −22°−30° (1989)
- Heating degree days
- 1090
- Cooling degree days
- 0