Salt Lake City Weather in September
The dry, hot weather of summer eases a little during September at Salt Lake City, Utah, but the abundant sunshine continues.
This page gives detailed information on the typical September temperature, precipitation, sun, humidity, wind and storms for Salt Lake City. The numbers here are historical averages based on climate data gathered at the Salt Lake City International Airport, located a few miles northwest of the city's center.
Temperature
| 81 °F | September average high | 27 °C |
| 56 °F | September average low | 14 °C |
| 18 days | 80 °F max. or more (27 °C) |
| 9 days | 50 °F min. or less (10 °C) |
Most days in September warm up to over 70 degrees Fahrenheit (21 degrees Celsius) in Salt Lake City. The city averages 5 days this month when the thermometer reaches into the 90s °F (over 32 °C). Temperatures in the 100s °F (above 38 °C) don't occur here every year during September.
The thermometer dips to 40 °F (4 °C) or below on an average of one night this month. But September does not normally get cold enough for frost.
Rain
| 1.1 in | total precipitation | 27 mm |
| 5 days | of rain |
Half the time, Salt Lake City receives 0.3 to 1.7 inches (9 to 43 mm) of rainfall in September. One in four years has drier weather, while another one in four is wetter. None of the precipitation falls as snow.
Sun
| 82 % | sunshine |
| 16 days | clear skies |
The sun's rays reach the ground in Salt Lake City during 82 percent of daylight hours on average in September, for a total of 306 hours in the month. Typically on 16 days this month the sky is mainly clear, with at most 30 percent cloud cover.
Sunlight in September at Salt Lake City lasts for 12 hours and 26 minutes a day on average. The longest day of the month is the 1st with 13 hours and 4 minutes of daylight. By the end of the month, the days have shortened to 11:47 from sunrise to sunset. These durations can vary by a minute or two from year to year.
Humidity
| 46 % | September average humidity |
The relative humidity in Salt Lake City during September usually peaks at 61 percent in the morning then drops to 29 percent in the afternoon.
| Local Time | 2 am | 5 am | 8 am | 11 am | 2 pm | 5 pm | 8 pm | 11 pm |
| Humidity % | 57 | 61 | 52 | 35 | 29 | 29 | 48 | 54 |
Wind
| 9.1 mph | September wind speed average | 14.6 kph |
September is a little windier than most other months in Salt Lake City.
Storms
| 1 day | rainfall of 0.5 inches (13 mm) or more |
| 5 days | with thunderstorms in September |
About twice a decade Salt Lake City has a September storm that dumps an inch or more of rain in one day.
Reference
The weather data here are long-term averages provided by the US National Centers for Environmental Information (NCEI). Temperature and precipitation are 1991-2020 normals while humidity and thunderstorms are 1961-1990 normals.