Fort Sumner weather by month
What a typical year looks like in Fort Sumner, New Mexico: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at Sumner Lake, 20 km from Fort Sumner; records cover 1948–2026.
The year at a glance
- Precipitation a year
- 14 in357 mm
- Snow a year
- 10 in24 cm
- Last spring freeze
- Apr 15
- First fall freeze
- Oct 27
- Heating degree days
- 3,598
- Cooling degree days
- 1,686
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are 11°−12° (heating, 99%) and 104°40° (cooling, 1%).
Month by month
Fort Sumner in January
Highs average 55°13° and lows 24°−4°, with 0.35 in8.9 mm of precipitation and 2.4 in6.1 cm of snow in a typical January.
- Record high
- 79°26° (1971)
- Record low
- −24°−31° (1963)
- Heating degree days
- 789
- Cooling degree days
- 0
Fort Sumner in February
Highs average 60°15° and lows 28°−2°, with 0.39 in9.9 mm of precipitation and 1.7 in4.3 cm of snow in a typical February.
- Record high
- 86°30° (2025)
- Record low
- −15°−26° (2011)
- Heating degree days
- 599
- Cooling degree days
- 0
Fort Sumner in March
Highs average 68°20° and lows 34°1°, with 0.61 in15 mm of precipitation and 0.7 in1.8 cm of snow in a typical March.
- Record high
- 98°37° (2026)
- Record low
- 3°−16° (1948)
- Heating degree days
- 442
- Cooling degree days
- 2
Fort Sumner in April
Highs average 75°24° and lows 41°5°, with 0.81 in21 mm of precipitation and 0.3 in0.8 cm of snow in a typical April.
- Record high
- 96°36° (2012)
- Record low
- 14°−10° (1996)
- Heating degree days
- 224
- Cooling degree days
- 20
Fort Sumner in May
Highs average 85°29° and lows 51°11°, with 1.2 in29 mm of precipitation in a typical May.
- Record high
- 104°40° (1974)
- Record low
- 25°−4° (2013)
- Heating degree days
- 58
- Cooling degree days
- 151
Fort Sumner in June
Highs average 94°35° and lows 61°16°, with 1.5 in38 mm of precipitation in a typical June.
- Record high
- 112°44° (2022)
- Record low
- 41°5° (1964)
- Heating degree days
- 1
- Cooling degree days
- 379
Fort Sumner in July
Highs average 96°35° and lows 65°18°, with 2.5 in63 mm of precipitation in a typical July.
- Record high
- 111°44° (2022)
- Record low
- 51°11° (1968)
- Heating degree days
- 0
- Cooling degree days
- 476
Fort Sumner in August
Highs average 93°34° and lows 64°18°, with 2.2 in57 mm of precipitation in a typical August.
- Record high
- 110°43° (2023)
- Record low
- 43°6° (2004)
- Heating degree days
- 0
- Cooling degree days
- 417
Fort Sumner in September
Highs average 86°30° and lows 56°13°, with 1.9 in48 mm of precipitation in a typical September.
- Record high
- 106°41° (2023)
- Record low
- 31°−1° (1999)
- Heating degree days
- 23
- Cooling degree days
- 209
Fort Sumner in OctoberThis month
Highs average 76°24° and lows 44°7°, with 1.5 in38 mm of precipitation and 0.3 in0.8 cm of snow in a typical October.
- Record high
- 97°36° (2024)
- Record low
- 10°−12° (2019)
- Heating degree days
- 191
- Cooling degree days
- 31
Fort Sumner in November
Highs average 65°18° and lows 32°0°, with 0.49 in12 mm of precipitation and 0.7 in1.8 cm of snow in a typical November.
- Record high
- 88°31° (2006)
- Record low
- −3°−19° (1976)
- Heating degree days
- 499
- Cooling degree days
- 1
Fort Sumner in December
Highs average 55°13° and lows 25°−4°, with 0.61 in15 mm of precipitation and 3 in9 cm of snow in a typical December.
- Record high
- 81°27° (1958)
- Record low
- −12°−24° (1978)
- Heating degree days
- 772
- Cooling degree days
- 0