Alamosa weather in September: Alamosa, Colorado: normal highs, lows, rain and records for September
Alamosa in September has a normal high of 74°F and a normal low of 37°F, a daily mean of 56°F, falling from 78°F on the 1st to 69°F by the 30th. Measurable precipitation falls on 7 days in a normal September, 0.98 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 24°C and low of 3°C, 25 mm of precipitation and 1 cm of snow in September.
- NOAA stationAlamosa-Bergman Field
- Station IDUSW00023061
- Location37.44°N 105.86°W
- Elevation7,533 ft (2,296 m)
- From the center3 miles
- Population9,906
- Jan 35° -1°
- Feb 41° 7°
- Mar 53° 18°
- Apr 60° 25°
- May 70° 34°
- Jun 80° 41°
- Jul 83° 47°
- Aug 81° 46°
- Sep 74° 37°
- Oct 63° 25°
- Nov 49° 12°
- Dec 35° 1°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Alamosa in September?
The normal high is 74°F and the normal low 37°F, for a daily mean of 55.9°F. September is 7.3°F cooler than August and 12.1°F warmer than October. September is the 4th warmest month of the year in Alamosa and the 3rd wettest. Across the month the normal high falls 9°F, from 78°F on September 1 to 69°F on September 30. From one year to the next September's mean temperature typically moves about 2.0°F either way (NOAA's standard deviation), so roughly two Septembers in three average between 54°F and 58°F.
Bars above: each day's normal high to low. Columns below: the chance of 0.01 inch or more of precipitation that day, on a scale of 0 to 100% (highest 28%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| September 1 | 78°F | 42°F | 28% | 10% |
| September 8 | 77°F | 40°F | 26% | 10% |
| September 15 | 75°F | 38°F | 23% | 9% |
| September 22 | 73°F | 35°F | 20% | 8% |
| September 30 | 69°F | 32°F | 17% | 7% |
Every day of September: normal high, low and chance of precipitation (warmest afternoon September 1, coldest night September 30)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| September 1 | 78°F | 42°F | 28% | 10% | 13 h |
| September 2 | 78°F | 42°F | 28% | 10% | 13 h |
| September 3 | 78°F | 42°F | 27% | 10% | 13 h |
| September 4 | 78°F | 42°F | 27% | 10% | 12 h 50 min |
| September 5 | 78°F | 41°F | 27% | 10% | 12 h 50 min |
| September 6 | 77°F | 41°F | 26% | 10% | 12 h 50 min |
| September 7 | 77°F | 41°F | 26% | 10% | 12 h 50 min |
| September 8 | 77°F | 40°F | 26% | 10% | 12 h 50 min |
| September 9 | 77°F | 40°F | 25% | 10% | 12 h 40 min |
| September 10 | 76°F | 40°F | 25% | 10% | 12 h 40 min |
| September 11 | 76°F | 39°F | 25% | 10% | 12 h 40 min |
| September 12 | 76°F | 39°F | 24% | 10% | 12 h 40 min |
| September 13 | 76°F | 39°F | 24% | 10% | 12 h 30 min |
| September 14 | 75°F | 38°F | 24% | 9% | 12 h 30 min |
| September 15 | 75°F | 38°F | 23% | 9% | 12 h 30 min |
| September 16 | 75°F | 37°F | 23% | 9% | 12 h 30 min |
| September 17 | 74°F | 37°F | 22% | 9% | 12 h 20 min |
| September 18 | 74°F | 37°F | 22% | 9% | 12 h 20 min |
| September 19 | 74°F | 36°F | 21% | 9% | 12 h 20 min |
| September 20 | 73°F | 36°F | 21% | 9% | 12 h 20 min |
| September 21 | 73°F | 35°F | 20% | 9% | 12 h 10 min |
| September 22 | 73°F | 35°F | 20% | 8% | 12 h 10 min |
| September 23 | 72°F | 35°F | 20% | 8% | 12 h 10 min |
| September 24 | 72°F | 34°F | 19% | 8% | 12 h 10 min |
| September 25 | 71°F | 34°F | 19% | 8% | 12 h 10 min |
| September 26 | 71°F | 33°F | 18% | 8% | 12 h |
| September 27 | 71°F | 33°F | 18% | 8% | 12 h |
| September 28 | 70°F | 32°F | 18% | 8% | 12 h |
| September 29 | 70°F | 32°F | 18% | 7% | 12 h |
| September 30 | 69°F | 32°F | 17% | 7% | 11 h 50 min |
- Normal high
- 74°FSeptember average
- Normal low
- 37°FSeptember average
- Precipitation
- 0.98 inmonth total
- Days with precipitation
- 70.01 inch or more
- Snowfall
- 0.5 inmonth total
- Nights at 32°F or colder
- 8
- Daylight
- 13 h to 11 h 50 minSeptember 1 to September 30
- Days at 70°F or more
- 24
- Days at 80°F or more
- 6
- Sunshine
- 86%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00023061; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain or snow in Alamosa in September?
On a given September day the chance of 0.01 inch or more is 23% on average, highest around September 1 (28%). In all, 0.98 in falls on 7 days of a normal September.
In a normal September in Alamosa, 8 nights fall to freezing and snowfall averages 0.5 inches.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00023061.
How humid and windy is Alamosa in September?
At 3 p.m. the normal temperature is 68°F with 21% relative humidity and a dew point of 26°F; at 6 a.m. it is 34°F with 79% humidity. The wind averages 6.9 mph, most often from the southwest in the afternoon. A dew point under 50°F feels dry.
| Time | Temperature | Dew point | Humidity | Wind | Clear or few clouds |
|---|---|---|---|---|---|
| 6 a.m. | 34°F | 28°F | 79% | 4.0 mph | 84% |
| 9 a.m. | 53°F | 32°F | 45% | 5.3 mph | 87% |
| noon | 65°F | 29°F | 26% | 8.7 mph | 86% |
| 3 p.m. | 68°F | 26°F | 21% | 10.7 mph | 79% |
| 6 p.m. | 58°F | 30°F | 34% | 8.7 mph | 79% |
| 9 p.m. | 48°F | 31°F | 51% | 7.3 mph | – |
Source: NOAA NCEI 1991-2020 hourly normals, station USW00023061. Hourly normals exist only for NOAA's first-order stations; a dash where NOAA publishes no value for that hour (the sky at some hours).
What are the records for September in Alamosa?
The warmest September temperature on Alamosa's official record (since 1906) is 89°F, on September 6, 2020; the coldest is 15°F, on September 30, 1985. The wettest September brought 2.98 in (2013); the snowiest, 15.3 inches (2020).
The September mean against the 1991-2020 normal of 55.9°F: 2021 58.4°F (+2.5), 2022 59.9°F (+4.0), 2023 56.8°F (+0.9), 2024 56.7°F (+0.8), 2025 55.2°F (−0.7), 2026 59.6°F (+3.7). 5 of 6 ran warmer than normal.
| September | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 58.4°F | +2.5°F | 0.32 in |
| 2022 | 59.9°F | +4.0°F | 0.53 in |
| 2023 | 56.8°F | +0.9°F | 0.92 in |
| 2024 | 56.7°F | +0.8°F | 0.77 in |
| 2025 | 55.2°F | −0.7°F | 1.02 in |
| 2026 | 59.6°F | +3.7°F | 2.27 in |
Source: records: ACIS, NWS threaded record ALSthr; recent months: ACIS, station USW00023061. Records and recent months use complete months only.
How does September in Alamosa compare across Colorado?
Across the 125 places PlainClimate covers in Colorado, September normal highs run from 62°F in Leadville to 86°F in Lamar; Alamosa's is 74°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.