Douglas County climate

Douglas County Weather in September

NOAA 1991-2020 normals for Castle Rock, 9.2 km from Douglas County

Average highs run from 81°F on September 1 to 71°F on September 30, and lows from 52°F to 41°F. Normal precipitation for the month is 1.39 in over about 6 wet days.

September day by day

The normal high and low for each date, and the record, in °F.

Normal daily high and low temperature at Douglas County, in °F, with the record for each date.20406080100151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
77°F
Average low
47°F
Precipitation
1.39 in
Snowfall
0.4 in
Record high
94°FSep 2, 2019
Record low
23°FSep 9, 2020
Chance of a freeze
42%
Days of 90°F or more
1.6
Daylight
13 h 02 min to 11 h 49 min
Cloud cover
43%
Humidity
45%
Dew point
36°F
Wind
7.6 mph

Every day of the month

A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.

DateNormal highNormal lowRecord highRecord lowChance wetChance of snow
Sep 181°F52°F93°F 201937°F 201026%0%
Sep 281°F52°F94°F 201931°F 201025%0%
Sep 381°F51°F86°F 201337°F 201025%0%
Sep 481°F51°F90°F 202031°F 202424%0%
Sep 580°F51°F89°F 201939°F 201124%0%
Sep 680°F50°F92°F 202035°F 202524%1%
Sep 780°F50°F89°F 202039°F 202123%1%
Sep 880°F50°F89°F 202225°F 202023%1%
Sep 979°F49°F88°F 202123°F 202023%1%
Sep 1079°F49°F90°F 202130°F 201622%1%
Sep 1179°F49°F90°F 202129°F 202022%1%
Sep 1278°F48°F86°F 201827°F 201422%1%
Sep 1378°F48°F84°F 201829°F 201421%1%
Sep 1478°F48°F84°F 201932°F 201221%1%
Sep 1577°F47°F82°F 201833°F 201220%1%
Sep 1677°F47°F85°F 201827°F 201620%1%
Sep 1777°F46°F85°F 201835°F 201020%1%
Sep 1876°F46°F87°F 201831°F 201219%1%
Sep 1976°F45°F84°F 201031°F 202419%1%
Sep 2075°F45°F85°F 201030°F 201519%1%
Sep 2175°F45°F80°F 201527°F 201918%1%
Sep 2275°F44°F81°F 201829°F 201118%1%
Sep 2374°F44°F83°F 201829°F 202118%1%
Sep 2474°F43°F79°F 202029°F 202118%1%
Sep 2573°F43°F87°F 202028°F 201017%1%
Sep 2673°F42°F87°F 202026°F 201617%1%
Sep 2772°F42°F82°F 201525°F 201817%1%
Sep 2872°F41°F84°F 201024°F 202016%1%
Sep 2972°F41°F81°F 202423°F 202016%1%
Sep 3071°F41°F83°F 202427°F 202016%2%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Douglas County, in percent, and of at least 0.1 inch of snowfall.01020301102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (MDT).

September 1
sunrise 6:28 AM, sunset 7:30 PM
September 30
sunrise 6:55 AM, sunset 6:44 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00051401 (Castle Rock), public domain. Records: NOAA GHCN-Daily, station USC00052494, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.