Jackson, WY weather in September
Jackson is mild in September, with some rain: highs average 68°F and nights drop to about 33°F. Rain falls on about 8 days. A great month for outdoor plans.
- Normal high
- 68°F
- Normal low
- 33°F
- Wet days
- 8
- 1.6 in total
- Muggy days
- 0
- dew point 65°F+
How September changes from start to finish
| September 1 | September 30 | |
|---|---|---|
| Normal high | 73°F | 62°F |
| Normal low | 36°F | 29°F |
| Chance of a wet day | 26% | 28% |
| Sunrise / sunset | 6:47 am / 7:59 pm | 7:19 am / 7:06 pm |
| Daylight | 13.2 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 and dew point under 60°F21 of 30
- Hot dayshigh 90°F or more0 of 30
- Muggy daysdaily mean dew point 65°F or more0 of 30
- Wet daysat least 0.01 in of rain or melted snow8 of 30
- Notable rainat least 0.10 in4 of 30
- Freezing nightslow 32°F or below15 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 and snow in September
Normal precipitation is 1.6 in; a dry September brings about 0.8 in and a wet one about 2.3 in (25th and 75th percentiles). About 1 day brings half an inch or more. Normal snowfall is 0.1 in.
How September varies from year to year
- Warmest September, 1991-20201994: average high 76°F
- Coolest September2017: average high 64°F
- Wettest September2019: 3.5 in
- Driest September2018: 0.05 in
- Highest reading88°F (September 6, 2002)
- Lowest reading8°F (September 22, 1995)
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 | 78°F | 68°F | 55°F |
| Normal low | 40°F | 33°F | 25°F |
| Wet days | 8 | 8 | 9 |
| Comfortable days | 13 | 21 | 7 |
| Daylight | 13.9 h | 12.5 h | 11.0 h |
Highs change by -10°F from August and -13°F into October.
Nearby alternatives in September
- Warmer: Billings, MT194 mi · high 75°F · 7 wet days
- Drier: Sun Valley, ID180 mi · high 69°F · 4 wet days
How Jackson ranks in September
- Normal high360th warmest of 378 cities; 4th of 4 in Wyoming
- Wet days202nd driest of 378
- Comfortable days13th most of 342
What to pack for Jackson in September
- A warm jacket – lows near 33°F, highs near 68°F
- Layers – afternoons near 68°F but nights near 33°F
- A rain jacket or umbrella – rain on about 8 days
- A hat and gloves – about 15 freezing nights
Heating and cooling
September has 437 heating degree days and 0 cooling degree days (base 65°F), 4% of the year's total heating and cooling demand.
Questions
How cold is Jackson in September?
The normal high is 68°F and the normal low is 33°F. From 1991 to 2020 the coldest September reading was 8°F (September 22, 1995).
Does it rain a lot in Jackson in September?
About 8 days in September have at least 0.01 in of precipitation, and the normal total is 1.6 in. The wettest September in 1991-2020 was in 2019 (3.5 in); the driest was in 2018 (0.05 in).
Does it snow in Jackson in September?
Yes. Normal snowfall in September is 0.1 in.
Is September a good time to visit Jackson?
September ranks 2nd of 12 months on our comfort score for Jackson (78 out of 100). It has about 21 comfortable days. The best months are June and September.
Where the numbers come from
- Temperature, rain and snowfall: Jackson (USC00484910), 0.5 mi N of the city center, 6,210 ft . NOAA normals and daily records, 1991-2020.
- Snow depth: Moose (USC00486428), 12 mi N of the city center, 6,444 ft (206 ft higher than the city). NOAA normals and daily records, 1991-2020.
- Frost dates: Moose 1 Nne (USW00004131), 13 mi NNE of the city center, 6,466 ft (228 ft higher than the city). NOAA normals and daily records, 1991-2020.
- Daily humidity and wind: Rexburg-Madison County Apt (726818-94194), 58 mi WNW of the city center, 4,858 ft (1,380 ft lower than the city). Hourly observations, 1991-2020.
- Not available for this location: humidity and wind by hour and cloud cover (no station close enough or similar enough in elevation).