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Weather Almanac: Castle Rock, CO 80109

🗓️ Historical norms for September

August October
Jan. Feb. Mar. Apr. May. Jun. Jul. Aug. Sep. Oct. Nov. Dec.
September avg. precipitation
🌧️ 1.24"
September days below freezing
📉 ≈1.1 days
Average September lows 43°F – 48°F
USDA Zone
5b
Annual extreme lows -15°F to -10°F
Last Spring Frost (36°F)
🌷 May 28
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First Fall Frost (36°F)
🍂 Sep 18
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📚 Rocky Mountain Month-By-Month Gardening: What to Do Each Month to Have A Beautiful Garden All Year - Colorado, Idaho, Montana, Utah, Wyoming

F: Forecast
H: Normal High Temp
L: Normal Low Temp
Jan. Feb. Mar. Apr. May. Jun. Jul. Aug. Sep. Oct. Nov. Dec.

Temperature climatic data from weather station: CASTLE ROCK (USC00051401)

Precipitation climatic data from weather station: CASTLE ROCK (USC00051401)

Agricultural climatic data from weather station: CASTLE ROCK (USC00051401)