Callao weather by month
What a typical year looks like in Callao, Missouri: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at Long Branch Reservoir, 10 km from Callao; records cover 1989–2026.
The year at a glance
- Precipitation a year
- 41.9 in1065 mm
- Snow a year
- Rare
- Last spring freeze
- Apr 14
- First fall freeze
- Oct 22
- Heating degree days
- 5,308
- Cooling degree days
- 1,307
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are −2°−19° (heating, 99%) and 98°37° (cooling, 1%).
Month by month
Callao in January
Highs average 35°2° and lows 19°−7°, with 1.6 in40 mm of precipitation in a typical January.
- Record high
- 72°22° (2013)
- Record low
- −19°−28° (1997)
- Heating degree days
- 1175
- Cooling degree days
- 0
Callao in February
Highs average 41°5° and lows 23°−5°, with 2.1 in53 mm of precipitation in a typical February.
- Record high
- 77°25° (2024)
- Record low
- −17°−27° (1996)
- Heating degree days
- 923
- Cooling degree days
- 0
Callao in March
Highs average 53°12° and lows 33°1°, with 2.9 in74 mm of precipitation in a typical March.
- Record high
- 84°29° (2026)
- Record low
- −5°−21° (1998)
- Heating degree days
- 687
- Cooling degree days
- 3
Callao in April
Highs average 64°18° and lows 44°6°, with 4.3 in110 mm of precipitation in a typical April.
- Record high
- 89°32° (2006)
- Record low
- 16°−9° (2018)
- Heating degree days
- 352
- Cooling degree days
- 17
Callao in May
Highs average 74°23° and lows 55°13°, with 5.4 in138 mm of precipitation in a typical May.
- Record high
- 95°35° (2018)
- Record low
- 32°0° (2005)
- Heating degree days
- 116
- Cooling degree days
- 98
Callao in June
Highs average 83°29° and lows 64°18°, with 5.5 in140 mm of precipitation in a typical June.
- Record high
- 102°39° (2012)
- Record low
- 41°5° (1993)
- Heating degree days
- 10
- Cooling degree days
- 268
Callao in July
Highs average 88°31° and lows 68°20°, with 4.3 in108 mm of precipitation in a typical July.
- Record high
- 105°41° (2012)
- Record low
- 49°9° (1997)
- Heating degree days
- 1
- Cooling degree days
- 397
Callao in August
Highs average 86°30° and lows 66°19°, with 3.8 in97 mm of precipitation in a typical August.
- Record high
- 106°41° (2003)
- Record low
- 47°8° (1994)
- Heating degree days
- 2
- Cooling degree days
- 344
Callao in September
Highs average 79°26° and lows 57°14°, with 3.9 in98 mm of precipitation in a typical September.
- Record high
- 101°38° (2000)
- Record low
- 30°−1° (1989)
- Heating degree days
- 59
- Cooling degree days
- 152
Callao in OctoberThis month
Highs average 67°19° and lows 45°7°, with 3.5 in88 mm of precipitation in a typical October.
- Record high
- 94°34° (2006)
- Record low
- 21°−6° (1993)
- Heating degree days
- 303
- Cooling degree days
- 27
Callao in November
Highs average 52°11° and lows 34°1°, with 2.7 in70 mm of precipitation in a typical November.
- Record high
- 80°27° (1999)
- Record low
- −1°−18° (1991)
- Heating degree days
- 660
- Cooling degree days
- 1
Callao in December
Highs average 40°5° and lows 24°−4°, with 2 in51 mm of precipitation in a typical December.
- Record high
- 74°23° (2021)
- Record low
- −28°−33° (1989)
- Heating degree days
- 1020
- Cooling degree days
- 0