St. George, UT weather in September
St. George is hot and dry in September: highs average 92°F and nights drop to about 61°F. There are about 2 days with rain. Midday heat is the main thing to plan around.
- Normal high
- 92°F
- Normal low
- 61°F
- Wet days
- 2
- 0.7 in total
- Daylight
- 12.4 h
How September changes from start to finish
| September 1 | September 30 | |
|---|---|---|
| Normal high | 97°F | 87°F |
| Normal low | 66°F | 55°F |
| Chance of a wet day | 9% | 8% |
| Sunrise / sunset | 7:05 am / 8:03 pm | 7:28 am / 7:19 pm |
| Daylight | 13.0 h | 11.8 h |
Chance of a wet day: average for the first and last 7 days of the month. Times are local clock time (Mountain Time).
What kind of days to expect
- Comfortable dayshigh 65-80°F (temperature only: no humidity station nearby)1 of 30
- Hot dayshigh 90°F or more23 of 30
- Wet daysat least 0.01 in of rain or melted snow2 of 30
- Notable rainat least 0.10 in1 of 30
- Freezing nightslow 32°F or below0 of 30
- Snow on the groundsnow depth 1 in or more0 of 30
Average days per September, counted from daily records for each year 1991-2020.
Rain in September
Normal precipitation is 0.7 in; a dry September brings about 0.04 in and a wet one about 1.0 in (25th and 75th percentiles). Days with half an inch or more are rare.
How September varies from year to year
- Warmest September, 1991-20201995: average high 98°F
- Coolest September2006: average high 89°F
- Wettest September1997: 2.7 in
- Driest September1992: no measurable precipitation
- Highest reading111°F (September 7, 2020)
- Lowest reading44°F (September 24, 2017)
From the station's daily records with NOAA quality flags removed; most recent date shown when a reading repeats.
September compared with August and October
| August | September | October | |
|---|---|---|---|
| Normal high | 100°F | 92°F | 79°F |
| Normal low | 70°F | 61°F | 47°F |
| Wet days | 3 | 2 | 3 |
| Comfortable days | 0 | 1 | 14 |
| Daylight | 13.6 h | 12.4 h | 11.2 h |
Highs change by -8°F from August and -13°F into October.
Nearby alternatives in September
- Warmer: Furnace Creek, CA187 mi · high 108°F · 1 wet day
- Cooler: Bryce Canyon City, UT88 mi · high 70°F · 7 wet days
How St. George ranks in September
- Normal high20th warmest of 378 cities; 1st of 7 in Utah
- Wet days66th driest of 378
What to pack for St. George in September
- Light, breathable clothing – highs near 92°F
- Layers – afternoons near 92°F but nights near 61°F
Heating and cooling
September has 5 heating degree days and 351 cooling degree days (base 65°F), 6% of the year's total heating and cooling demand.
Questions
How hot is St. George in September?
The normal high is 92°F and the normal low is 61°F. From 1991 to 2020 the hottest September reading was 111°F (September 7, 2020).
Does it rain a lot in St. George in September?
About 2 days in September have at least 0.01 in of precipitation, and the normal total is 0.7 in. The wettest September in 1991-2020 was in 1997 (2.7 in); the driest was in 1992, with no measurable precipitation.
Is September a good time to visit St. George?
September ranks 10th of 12 months on our comfort score for St. George (39 out of 100). It has about 1 comfortable day (judged by temperature only) and about 23 days at 90°F or hotter. The best months are March and April.
Where the numbers come from
- Temperature, rain, snowfall, snow depth and frost dates: St George (USC00427516), 1.6 mi NW of the city center, 2,857 ft (161 ft higher than the city). NOAA normals and daily records, 1991-2020.
- Not available for this location: humidity and wind by hour, cloud cover and daily humidity and wind (no station close enough or similar enough in elevation).