Duncan weather by month
What a typical year looks like in Duncan, Oklahoma: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at Velma 7nw Mesonet, 19 km from Duncan; records cover 2007–2026.
The year at a glance
- Precipitation a year
- 0 in0 mm
- Snow a year
- Rare
- Last spring freeze
- Apr 5
- First fall freeze
- Nov 10
- Heating degree days
- 3,105
- Cooling degree days
- 2,158
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are 14°−10° (heating, 99%) and 106°41° (cooling, 1%).
Month by month
Duncan in January
Highs average 52°11° and lows 30°−1°, with — of precipitation in a typical January.
- Record high
- 82°28° (2009)
- Record low
- −3°−19° (2017)
- Heating degree days
- 741
- Cooling degree days
- 0
Duncan in February
Highs average 57°14° and lows 34°1°, with — of precipitation in a typical February.
- Record high
- 88°31° (2017)
- Record low
- −13°−25° (2021)
- Heating degree days
- 553
- Cooling degree days
- 3
Duncan in March
Highs average 66°19° and lows 43°6°, with — of precipitation in a typical March.
- Record high
- 94°34° (2026)
- Record low
- 6°−14° (2014)
- Heating degree days
- 356
- Cooling degree days
- 18
Duncan in April
Highs average 73°23° and lows 50°10°, with — of precipitation in a typical April.
- Record high
- 98°37° (2011)
- Record low
- 24°−4° (2009)
- Heating degree days
- 161
- Cooling degree days
- 50
Duncan in May
Highs average 81°27° and lows 59°15°, with — of precipitation in a typical May.
- Record high
- 98°37° (2008)
- Record low
- 34°1° (2013)
- Heating degree days
- 38
- Cooling degree days
- 190
Duncan in June
Highs average 89°32° and lows 68°20°, with — of precipitation in a typical June.
- Record high
- 109°43° (2011)
- Record low
- 54°12° (2020)
- Heating degree days
- 0
- Cooling degree days
- 402
Duncan in July
Highs average 94°34° and lows 72°22°, with — of precipitation in a typical July.
- Record high
- 112°44° (2022)
- Record low
- 58°14° (2013)
- Heating degree days
- 0
- Cooling degree days
- 555
Duncan in August
Highs average 95°35° and lows 71°22°, with — of precipitation in a typical August.
- Record high
- 112°44° (2012)
- Record low
- 55°13° (2015)
- Heating degree days
- 0
- Cooling degree days
- 547
Duncan in September
Highs average 86°30° and lows 63°17°, with — of precipitation in a typical September.
- Record high
- 108°42° (2023)
- Record low
- 45°7° (2011)
- Heating degree days
- 11
- Cooling degree days
- 298
Duncan in OctoberThis month
Highs average 75°24° and lows 52°11°, with — of precipitation in a typical October.
- Record high
- 96°36° (2014)
- Record low
- 23°−5° (2019)
- Heating degree days
- 140
- Cooling degree days
- 88
Duncan in November
Highs average 64°18° and lows 40°4°, with — of precipitation in a typical November.
- Record high
- 90°32° (2025)
- Record low
- 15°−9° (2019)
- Heating degree days
- 406
- Cooling degree days
- 7
Duncan in December
Highs average 54°12° and lows 31°0°, with — of precipitation in a typical December.
- Record high
- 85°29° (2025)
- Record low
- 6°−14° (2016)
- Heating degree days
- 699
- Cooling degree days
- 0