World Resorts USA Spearfish Weather

Spearfish weather in September

Weather in Spearfish: September

Average day temperature: 75.8°F
Average night temperature: 58.8°F
Number of sunny days: 23 days
Day length: 11.8 - 13.2 hours
Number of rainy days: 0 days
Precipitation totals: 0.2 in.

Air temperature in September, °F

Show year:
2025
2024
2023

The highest day temperature during September of 2025 was 85°F. At the same time the lowest night temperature was 41°F. Daily and nightly averages during September were 74.1°F and 56.9°F.

Sunny, partly cloudy and cloudy days

Mostly all days in September are sunny but cloudy days are also possible.

Precipitation total in September, in.

Precipitation total value in Spearfish in September is 0.2 in. Other months of the year show relatively similar values.

Wind speed in September, mph

The average wind speed value in September is 8.0 mph It makes September one of the least windy months of the year.

Average sunny hours

This chart shows average number of hours during the day when sunlight can reach the ground. It depends on day length and cloudiness during the day. The average number of sunny hours in September is: 10.3.

Best time for vacation in Spearfish

Sunniest months:
September 23 days
August 22 days
July 20 days
Warmest months:
July 83.3 °F
August 82.1 °F
September 75.8 °F
Coldest months:
January 32.4 °F
February 33.8 °F
December 36.7 °F
Rainiest months:
May 3 days
July 1 day
April 1 day
Windiest months:
April 10.4 mph
May 9.5 mph
December 9.3 mph

Spearfish on a weather map

Spearfish
+81°F
E 23 mph
Feels like: +77°F
Precip.: 0%
Places in USA:
Name
°F
+66°F
+79°F
+99°F
+75°F
+91°F
+88°F
+73°F
+86°F
+88°F
+72°F
+81°F
+79°F
+95°F
+91°F
+86°F
24 Hours Forecast
Spearfish
Local time: 15:39
June 29, monday
1800
79°F
E
17 mph
2100
73°F
E
8 mph
June 30, tuesday
0000
52°F
E
6 mph
0300
46°F
E
4 mph
0600
48°F
N
4 mph
0900
72°F
E
7 mph
1200
84°F
E
10 mph
1500
88°F
SE
10 mph
Units of measurement: °C / °F