Castle Rock weather by month
Average highs run from 46°F in January to 86°F in July, and January nights average 18°F. It gets 18 inches of rain and melted snow a year and 58 inches of snow. Nights drop below freezing about 167 times a year. The most comfortable months are June to September.
Best time to visit Castle Rock
For comfortable weather, go in June to September. In those months the average high stays between 62°F and 86°F, nights average 42°F or warmer, and rain stays under 4.5 inches for the month.
Month by month
| Month | High | Low | Precip. | Snow | Wet days | Days 90°F+ | Nights below 32°F | Feels |
|---|---|---|---|---|---|---|---|---|
| January | 46°F | 18°F | 0.6 in | 8.0 in | 2 | 0 | 30 | cold |
| February | 47°F | 20°F | 0.7 in | 10.7 in | 3 | 0 | 26 | cold |
| March | 54°F | 27°F | 1.5 in | 10.7 in | 4 | 0 | 24 | cool |
| April | 59°F | 33°F | 2.1 in | 8.3 in | 4 | 0 | 17 | cool |
| May | 68°F | 42°F | 2.0 in | 1.1 in | 5 | 0 | 4 | mild days, chilly nights |
| June | 80°F | 51°F | 2.2 in | 0.0 in | 5 | 4 | 0 | warm |
| July | 86°F | 56°F | 2.3 in | 0.0 in | 5 | 11 | 0 | warm |
| August | 84°F | 55°F | 2.5 in | 0.0 in | 5 | 6 | 0 | warm |
| September | 77°F | 47°F | 1.4 in | 0.4 in | 3 | 2 | 1 | warm |
| October | 65°F | 35°F | 0.9 in | 2.7 in | 3 | 0 | 12 | mild days, chilly nights |
| November | 54°F | 26°F | 0.8 in | 6.7 in | 2 | 0 | 24 | cool |
| December | 46°F | 18°F | 0.7 in | 8.9 in | 2 | 0 | 29 | cold |
| Year | 64°F avg | 35°F avg | 17.6 in | 57.5 in | 42 | 23 | 167 |
"Wet days" are days with at least 0.1 inch of precipitation. "Feels" is a plain-language label for the average high. Normals for 1991-2020 from NOAA NCEI, station Castle Rock, CO (USC00051401), 3.8 miles from the city center. Averages describe typical conditions, not a forecast.
Sunrise, sunset and daylight in Castle Rock
The shortest day is December 21, with 9h 23m of daylight; the longest is June 21, with 14h 56m. The earliest sunset comes around December 2 (4:35 pm) and the latest around June 25 (8:30 pm). The sun sets after 8 pm on 94 days a year.
| On the 15th of | Sunrise | Sunset | Daylight |
|---|---|---|---|
| January | 7:17 am | 5:00 pm | 9h 42m |
| February | 6:51 am | 5:36 pm | 10h 45m |
| March | 7:10 am | 7:06 pm | 11h 56m |
| April | 6:22 am | 7:37 pm | 13h 15m |
| May | 5:45 am | 8:06 pm | 14h 20m |
| June | 5:32 am | 8:27 pm | 14h 56m |
| July | 5:45 am | 8:25 pm | 14h 40m |
| August | 6:12 am | 7:54 pm | 13h 42m |
| September | 6:41 am | 7:07 pm | 12h 26m |
| October | 7:09 am | 6:19 pm | 11h 10m |
| November | 6:43 am | 4:44 pm | 10h 01m |
| December | 7:12 am | 4:36 pm | 9h 24m |
Calculated for 2026 at the center of Castle Rock with NOAA's solar equations, in local clock time (Mountain Time, including daylight saving time where it applies). Times shift by a minute or two from year to year.
Is Castle Rock getting warmer?
The last 10 years averaged 1.8°F warmer than the 20th century. See the climate stripes for Castle Rock.Frequently asked questions
What is the warmest month in Castle Rock?
July is the warmest month, with an average high of 86°F and an average low of 56°F (NOAA 1991-2020 normals).
What is the coldest month in Castle Rock?
January is the coldest, with average lows of 18°F and highs of 46°F.
What is the rainiest month in Castle Rock?
August gets the most precipitation, 2.5 inches on average. January is the driest at 0.6 inches.
Does it snow in Castle Rock?
Yes. Castle Rock averages 58 inches of snow a year.
When is the best time to visit Castle Rock?
For comfortable weather, June to September. Those months average highs between 62 and 86°F with lows of 42°F or more and modest rain.
Thinking of moving to Castle Rock?
See what homes, rent and everyday prices cost, who lives there and how it compares with nearby cities on the full Castle Rock profile.
Compare the weather: Castle Rock vs Highlands Ranch, Castle Rock vs Centennial, Castle Rock vs Aurora, Castle Rock vs Denver.