San Juan County Weather in September
Average highs run from 82°F on September 1 to 71°F on September 30, and lows from 56°F to 45°F. Normal precipitation for the month is 1.61 in over about 6 wet days.
September day by day
The normal high and low for each date, and the record, in °F.
- Normal low
- Normal high
- Record high
- Record low
September at a glance
- Average high
- 77°F
- Average low
- 51°F
- Precipitation
- 1.61 in
- Record high
- 100°FSep 1, 1905
- Record low
- 20°FSep 26, 1908
- Chance of a freeze
- 13%
- Days of 90°F or more
- 0.8
- Daylight
- 12 h 58 min to 11 h 50 min
- Cloud cover
- 38%
- Humidity
- 36%
- Dew point
- 36°F
- Wind
- 7.4 mph
Every day of the month
A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.
| Date | Normal high | Normal low | Record high | Record low | Chance wet | Chance of snow |
|---|---|---|---|---|---|---|
| Sep 1 | 82°F | 56°F | 100°F 1905 | 40°F 1932 | 23% | 0% |
| Sep 2 | 82°F | 56°F | 96°F 1995 | 38°F 1961 | 23% | 0% |
| Sep 3 | 82°F | 55°F | 95°F 1995 | 40°F 1908 | 23% | 0% |
| Sep 4 | 81°F | 55°F | 94°F 1995 | 33°F 1961 | 23% | 0% |
| Sep 5 | 81°F | 55°F | 95°F 1995 | 36°F 1922 | 23% | 0% |
| Sep 6 | 81°F | 55°F | 95°F 2020 | 32°F 1906 | 23% | 0% |
| Sep 7 | 81°F | 54°F | 95°F 2020 | 38°F 1922 | 22% | 0% |
| Sep 8 | 80°F | 54°F | 94°F 1979 | 37°F 2020 | 22% | 0% |
| Sep 9 | 80°F | 54°F | 91°F 1959 | 34°F 1929 | 22% | 0% |
| Sep 10 | 80°F | 53°F | 91°F 1990 | 35°F 1922 | 22% | 0% |
| Sep 11 | 79°F | 53°F | 92°F 1990 | 35°F 1922 | 22% | 0% |
| Sep 12 | 79°F | 53°F | 94°F 1990 | 33°F 1985 | 22% | 0% |
| Sep 13 | 78°F | 52°F | 94°F 1990 | 31°F 1952 | 22% | 0% |
| Sep 14 | 78°F | 52°F | 94°F 1990 | 32°F 1915 | 21% | 0% |
| Sep 15 | 78°F | 52°F | 92°F 2000 | 32°F 1914 | 21% | 0% |
| Sep 16 | 77°F | 51°F | 93°F 2000 | 34°F 1906 | 21% | 0% |
| Sep 17 | 77°F | 51°F | 93°F 1928 | 29°F 1906 | 21% | 0% |
| Sep 18 | 76°F | 50°F | 90°F 1928 | 23°F 1971 | 20% | 0% |
| Sep 19 | 76°F | 50°F | 89°F 1956 | 33°F 1922 | 20% | 0% |
| Sep 20 | 76°F | 50°F | 92°F 1928 | 28°F 1978 | 20% | 0% |
| Sep 21 | 75°F | 49°F | 88°F 2015 | 28°F 1965 | 19% | 0% |
| Sep 22 | 75°F | 49°F | 94°F 1949 | 31°F 1912 | 19% | 0% |
| Sep 23 | 74°F | 48°F | 90°F 1905 | 30°F 1912 | 19% | 0% |
| Sep 24 | 74°F | 48°F | 86°F 1922 | 27°F 1913 | 19% | 0% |
| Sep 25 | 73°F | 47°F | 90°F 1966 | 32°F 1913 | 18% | 0% |
| Sep 26 | 73°F | 47°F | 90°F 2003 | 20°F 1908 | 18% | 0% |
| Sep 27 | 72°F | 47°F | 89°F 2010 | 20°F 1908 | 18% | 0% |
| Sep 28 | 72°F | 46°F | 90°F 1905 | 26°F 1908 | 18% | 0% |
| Sep 29 | 71°F | 46°F | 89°F 2010 | 32°F 1922 | 18% | 0% |
| Sep 30 | 71°F | 45°F | 87°F 2010 | 28°F 1907 | 18% | 0% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (MDT).
- September 1
- sunrise 6:50 AM, sunset 7:48 PM
- September 30
- sunrise 7:14 AM, sunset 7:04 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00426053 (Natural Bridges Nm), public domain. Records: NOAA GHCN-Daily, station USC00420738, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.