San Luis weather by month
What a typical year looks like in San Luis, Colorado: average highs and lows, rain and snow, and the warmest and coldest days on record. No nearby active station has official 1991–2020 normals, so these are forecast.blue’s own averages computed from daily observations at San Acacio, 18 km from San Luis, over its available record (2000–2026) — not an NCEI normal; records cover 2000–2026.
The year at a glance
- Precipitation a year
- 5.2 in132 mm
- Snow a year
- Rare
- Last spring freeze
- May 31
- First fall freeze
- Sep 20
- Heating degree days
- —
- Cooling degree days
- —
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are −16°−27° (heating, 99%) and 90°32° (cooling, 1%).
Month by month
San Luis in January
Highs average 37°3° and lows 3°−16°, with — of precipitation in a typical January.
- Record high
- 60°16° (2018)
- Record low
- −32°−36° (2017)
- Heating degree days
- —
- Cooling degree days
- —
San Luis in February
Highs average 42°5° and lows 11°−12°, with — of precipitation in a typical February.
- Record high
- 65°18° (2026)
- Record low
- −27°−33° (2011)
- Heating degree days
- —
- Cooling degree days
- —
San Luis in March
Highs average 52°11° and lows 19°−7°, with — of precipitation in a typical March.
- Record high
- 81°27° (2026)
- Record low
- −9°−23° (2002)
- Heating degree days
- —
- Cooling degree days
- —
San Luis in April
Highs average 60°16° and lows 26°−4°, with — of precipitation in a typical April.
- Record high
- 79°26° (2020)
- Record low
- 1°−17° (2023)
- Heating degree days
- —
- Cooling degree days
- —
San Luis in May
Highs average 68°20° and lows 34°1°, with 0.8 in20 mm of precipitation in a typical May.
- Record high
- 99°37° (2026)
- Record low
- 11°−12° (2008)
- Heating degree days
- —
- Cooling degree days
- —
San Luis in June
Highs average 79°26° and lows 43°6°, with 0.6 in15 mm of precipitation in a typical June.
- Record high
- 93°34° (2015)
- Record low
- 26°−3° (2007)
- Heating degree days
- —
- Cooling degree days
- —
San Luis in July
Highs average 83°29° and lows 49°9°, with 1.5 in38 mm of precipitation in a typical July.
- Record high
- 95°35° (2023)
- Record low
- 35°2° (2004)
- Heating degree days
- —
- Cooling degree days
- —
San Luis in August
Highs average 81°27° and lows 47°8°, with 1.1 in28 mm of precipitation in a typical August.
- Record high
- 94°34° (2026)
- Record low
- 33°1° (2009)
- Heating degree days
- —
- Cooling degree days
- —
San Luis in September
Highs average 75°24° and lows 39°4°, with 1.2 in30 mm of precipitation in a typical September.
- Record high
- 99°37° (2026)
- Record low
- 18°−8° (2008)
- Heating degree days
- —
- Cooling degree days
- —
San Luis in OctoberThis month
Highs average 63°17° and lows 28°−2°, with — of precipitation in a typical October.
- Record high
- 80°27° (2015)
- Record low
- −4°−20° (2019)
- Heating degree days
- —
- Cooling degree days
- —
San Luis in November
Highs average 50°10° and lows 16°−9°, with — of precipitation in a typical November.
- Record high
- 72°22° (2025)
- Record low
- −21°−29° (2004)
- Heating degree days
- —
- Cooling degree days
- —
San Luis in December
Highs average 39°4° and lows 6°−15°, with — of precipitation in a typical December.
- Record high
- 63°17° (2021)
- Record low
- −28°−33° (2007)
- Heating degree days
- —
- Cooling degree days
- —
Blanca 4 NW station, 1909–2010: records and averages
This station is no longer reporting, but its 1909–2010 record is the longest and most local history available. These are its own averages over its own period of record — not NCEI normals, and not the same station as the computed averages above.
January
Average high 35°2°, low 2°−17°, 0.3 in7.6 mm precipitation.
Record high 61°16° (1971); record low −38°−39° (1963).
February
Average high 41°5°, low 9°−13°, 0.3 in7.6 mm precipitation.
Record high 66°19° (1914); record low −24°−31° (1989).
March
Average high 49°10°, low 18°−8°, 0.5 in13 mm precipitation.
Record high 72°22° (1997); record low −14°−26° (1929).
April
Average high 58°15°, low 25°−4°, 0.7 in18 mm precipitation.
Record high 80°27° (1981); record low 0°−18° (1928).
May
Average high 68°20°, low 34°1°, 0.9 in23 mm precipitation.
Record high 89°32° (2002); record low 2°−17° (2008).
June
Average high 77°25°, low 42°5°, 0.7 in18 mm precipitation.
Record high 97°36° (1961); record low 20°−7° (2008).
July
Average high 82°28°, low 47°8°, 1.6 in41 mm precipitation.
Record high 97°36° (1964); record low 29°−2° (2004).
August
Average high 79°26°, low 46°8°, 1.5 in38 mm precipitation.
Record high 94°34° (2008); record low 29°−2° (1964).
September
Average high 73°23°, low 38°3°, 0.9 in23 mm precipitation.
Record high 92°33° (2007); record low 16°−9° (1970).
October
Average high 62°17°, low 27°−3°, 0.7 in18 mm precipitation.
Record high 80°27° (1910); record low −4°−20° (1975).
November
Average high 48°9°, low 15°−10°, 0.4 in10 mm precipitation.
Record high 71°22° (1926); record low −19°−28° (1929).
December
Average high 36°2°, low 4°−16°, 0.3 in7.6 mm precipitation.
Record high 60°16° (1910); record low −34°−37° (1961).
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