🌷 Your Ultimate Garden Calendar!

Weather Almanac: Boulder, CO 80310

🗓️ Historical norms for September

August October
Jan. Feb. Mar. Apr. May. Jun. Jul. Aug. Sep. Oct. Nov. Dec.
September avg. precipitation
🌧️ 1.68"
September days below freezing
📉 ≈0.6 days
Average September lows 46°F – 50°F
USDA Zone
6a
Annual extreme lows -10°F to -5°F
Last Spring Frost (36°F)
🌷 May 22
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First Fall Frost (36°F)
🍂 Sep 23
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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: BOULDER (USC00050848)

Precipitation climatic data from weather station: BOULDER (USC00050848)

Agricultural climatic data from weather station: BOULDER (USC00050848)