Overall on the next 14 days there will be 1 days with snow in Casper and a total of 12.6 cm of snow.
It will be snowy on the following days:
Casper weather in September 2026
Click on a day for an hourly weather forecast
Friday
Sep 18
0.3 mm
26° / 13°
Saturday
Sep 19
0 mm
24° / 12°
Sunday
Sep 20
4 mm
17° / 10°
Monday
Sep 21
0 mm
20° / 9°
Tuesday
Sep 22
0 mm
23° / 11°
Wednesday
Sep 23
0 mm
23° / 15°
Thursday
Sep 24
0 mm
24° / 13°
Friday
Sep 25
0 mm
25° / 14°
Saturday
Sep 26
0 mm
24° / 15°
Sunday
Sep 27
0.5 mm
20° / 12°
Monday
Sep 28
0 mm
17° / 7°
Tuesday
Sep 29
0 mm
12° / 3°
Wednesday
Sep 30
12.6 cm
4° / 0°
Thursday
Oct 1
0 mm
9° / 0°
🌨️ Snowy days in Casper 2026 (September)
The average weather in Casper in September
The temperatures in Casper in September are quite cold with temperatures between 9°C and 22°C, warm clothes are a must.
You can expect about 3 to 8 days of rain in Casper during the month of September. It’s a good idea to bring along your umbrella so that you don’t get caught in poor weather.
Please note that Casper can expect a few days of snow in September.
Our weather forecast can give you a great sense of what weather to expect in Casper in September 2026.
If you’re planning to visit Casper in the near future, we highly recommend that you review the 14 day weather forecast for Casper before you arrive.
Temperatures
22° / 9°
Rainy Days
3
Snowy Days
1
Dry Days
26
Rainfall
37
mm
Sun Hours
11.8
Hrs
Historic average weather for September
Click on a day for an hourly weather forecast
Explore the weather in Casper in other months
Casper annual weather
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | -1° / -12° | 5 | 12 | 14 | 37 mm | Awful | Casper in January |
| February | -1° / -12° | 6 | 6 | 17 | 51 mm | Awful | Casper in February |
| March | 6° / -6° | 6 | 11 | 14 | 72 mm | Awful | Casper in March |
| April | 9° / -3° | 6 | 10 | 14 | 92 mm | Bad | Casper in April |
| May | 15° / 3° | 9 | 14 | 8 | 99 mm | Bad | Casper in May |
| June | 23° / 9° | 4 | 25 | 1 | 49 mm | Perfect | Casper in June |
| July | 28° / 13° | 2 | 29 | 0 | 40 mm | Perfect | Casper in July |
| August | 27° / 13° | 2 | 29 | 0 | 38 mm | Perfect | Casper in August |
| September | 22° / 9° | 3 | 26 | 1 | 37 mm | Good | Casper in September |
| October | 12° / 0° | 3 | 19 | 8 | 61 mm | Bad | Casper in October |
| November | 6° / -5° | 5 | 14 | 11 | 35 mm | Awful | Casper in November |
| December | -1° / -11° | 7 | 10 | 14 | 45 mm | Awful | Casper in December |
Temperatures in Casper in September
Rain in Casper in September
Recommended Hotels in Casper
Weather in Casper in September - FAQ
What is the average temperature in Casper in September?
The average temperature in Casper in September is 9/22° C.
What is the chance of rain in Casper in September?
On average, there are 3 rainy days in Casper during September.
Weather wise, is September a good time to visit Casper?
The weather in Casper in September is good.
Can it snow in Casper in September?
On average, there are 1 snowy days in Casper in September.
More about the weather in Casper