World Resorts USA Boulder Weather

Boulder weather in September

Weather in Boulder: September

Average day temperature: 68.7°F
Average night temperature: 50.1°F
Number of sunny days: 21 days
Day length: 11.8 - 13.1 hours
Number of rainy days: 1 day
Precipitation totals: 0.7 in.

Air temperature in September, °F

Show year:
2024
2023
2022

The highest day temperature during September of 2024 was 88°F. At the same time the lowest night temperature was 46°F. Day and night temperature averages during September were 76.6°F and 58.3°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 Boulder in September is 0.7 in. Other months of the year show relatively similar values.

Wind speed in September, mph

The average wind speed value in September is 6.6 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: 9.5.

Best time for vacation in Boulder

Sunniest months:
September 21 days
October 21 days
November 19 days
Warmest months:
July 74.0 °F
August 73.1 °F
September 68.7 °F
Coldest months:
January 29.5 °F
February 30.0 °F
December 34.7 °F
Rainiest months:
June 6 days
July 5 days
May 4 days
Windiest months:
December 9.0 mph
February 8.8 mph
January 8.6 mph

Boulder on a weather map

Boulder
+46°F
E 11 mph
Feels like: +41°F
Precip.: 0%
Places in USA:
Name
°F
+16°F
+25°F
+75°F
+75°F
+54°F
+54°F
+63°F
+21°F
+52°F
+52°F
+54°F
+50°F
+48°F
+46°F
+23°F
24 Hours Forecast
Boulder
Local time: 00:54
December 22, sunday
0300
46°F
E
13 mph
0600
46°F
E
14 mph
0900
46°F
E
12 mph
1200
54°F
E
7 mph
1500
54°F
E
6 mph
1800
50°F
E
9 mph
2100
46°F
E
10 mph
December 23, monday
0000
43°F
E
10 mph
Units of measurement: °C / °F