Keystone weather by month
What a typical year looks like in Keystone, Indiana: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at Hartford City 4 Ese, 18 km from Keystone; records cover 1959–2026.
The year at a glance
- Precipitation a year
- 41.7 in1060 mm
- Snow a year
- 32 in82 cm
- Last spring freeze
- Apr 21
- First fall freeze
- Oct 16
- Heating degree days
- 5,827
- Cooling degree days
- 887
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are −4°−20° (heating, 99%) and 92°33° (cooling, 1%).
Month by month
Keystone in January
Highs average 33°1° and lows 19°−7°, with 2.7 in68 mm of precipitation and 9 in23 cm of snow in a typical January.
- Record high
- 65°18° (2008)
- Record low
- −26°−32° (1994)
- Heating degree days
- 1209
- Cooling degree days
- 0
Keystone in February
Highs average 37°3° and lows 21°−6°, with 2.4 in60 mm of precipitation and 8 in21 cm of snow in a typical February.
- Record high
- 73°23° (2000)
- Record low
- −17°−27° (1982)
- Heating degree days
- 1002
- Cooling degree days
- 0
Keystone in March
Highs average 48°9° and lows 30°−1°, with 3.3 in84 mm of precipitation and 5 in13 cm of snow in a typical March.
- Record high
- 85°29° (2012)
- Record low
- −10°−23° (1984)
- Heating degree days
- 806
- Cooling degree days
- 2
Keystone in April
Highs average 61°16° and lows 41°5°, with 3.9 in99 mm of precipitation and 0.6 in1.5 cm of snow in a typical April.
- Record high
- 87°31° (1986)
- Record low
- 8°−13° (1982)
- Heating degree days
- 429
- Cooling degree days
- 10
Keystone in May
Highs average 72°22° and lows 52°11°, with 4.2 in108 mm of precipitation in a typical May.
- Record high
- 94°34° (2012)
- Record low
- 26°−3° (1966)
- Heating degree days
- 166
- Cooling degree days
- 70
Keystone in June
Highs average 80°27° and lows 61°16°, with 4.4 in113 mm of precipitation in a typical June.
- Record high
- 104°40° (2012)
- Record low
- 37°3° (1966)
- Heating degree days
- 21
- Cooling degree days
- 198
Keystone in July
Highs average 83°28° and lows 64°18°, with 4.2 in107 mm of precipitation in a typical July.
- Record high
- 102°39° (2012)
- Record low
- 45°7° (1963)
- Heating degree days
- 4
- Cooling degree days
- 270
Keystone in August
Highs average 82°28° and lows 62°17°, with 4.3 in110 mm of precipitation in a typical August.
- Record high
- 98°37° (1983)
- Record low
- 35°2° (1965)
- Heating degree days
- 9
- Cooling degree days
- 217
Keystone in September
Highs average 76°25° and lows 55°13°, with 3.5 in88 mm of precipitation in a typical September.
- Record high
- 97°36° (2011)
- Record low
- 29°−2° (1995)
- Heating degree days
- 86
- Cooling degree days
- 101
Keystone in OctoberThis month
Highs average 64°18° and lows 44°7°, with 2.9 in73 mm of precipitation and 0.2 in0.5 cm of snow in a typical October.
- Record high
- 91°33° (2019)
- Record low
- 19°−7° (1981)
- Heating degree days
- 354
- Cooling degree days
- 18
Keystone in November
Highs average 50°10° and lows 34°1°, with 3.3 in83 mm of precipitation and 2 in5.1 cm of snow in a typical November.
- Record high
- 79°26° (2016)
- Record low
- 3°−16° (2019)
- Heating degree days
- 696
- Cooling degree days
- 1
Keystone in December
Highs average 38°3° and lows 25°−4°, with 2.7 in68 mm of precipitation and 7 in18 cm of snow in a typical December.
- Record high
- 71°22° (1982)
- Record low
- −22°−30° (1989)
- Heating degree days
- 1045
- Cooling degree days
- 0