Boulder September Weather Averages

Colorado, United States of America

September Weather Averages for Boulder

High Temp24°C75°F
Low Temp11°C52°F
Avg Temp17°C63°F
Sunshine Hours284 hours 
Rainfall43.17 mm1.70 In
Rain days5 days 
Pressure1016 mb30 In

 

Boulder September Averages Year by Year

YearHigh TempLow TempAvg TempSunshine HoursRainfallRain daysPressure
200922°C / 71°F9°C / 49°F15°C / 59°F308 hours40.93 mm / 1.61 In7 days1018 mb / 31 In
201025°C / 77°F10°C / 51°F17°C / 63°F343 hours1.10 mm / 0.04 In0 days1015 mb / 30 In
201121°C / 70°F10°C / 50°F15°C / 59°F292 hours53.98 mm / 2.13 In6 days1019 mb / 31 In
201222°C / 72°F11°C / 52°F16°C / 61°F317 hours51.52 mm / 2.03 In3 days1018 mb / 31 In
201322°C / 71°F11°C / 53°F16°C / 61°F273 hours164.58 mm / 6.48 In11 days1014 mb / 30 In
201422°C / 72°F11°C / 51°F16°C / 60°F305 hours45.16 mm / 1.78 In5 days1016 mb / 30 In
201525°C / 76°F12°C / 54°F18°C / 64°F286 hours9.23 mm / 0.36 In3 days1015 mb / 30 In
201622°C / 71°F10°C / 50°F16°C / 60°F303 hours10.48 mm / 0.41 In2 days1017 mb / 31 In
201721°C / 69°F10°C / 51°F15°C / 59°F261 hours46.30 mm / 1.82 In8 days1016 mb / 30 In
201824°C / 75°F11°C / 52°F17°C / 63°F310 hours11.26 mm / 0.44 In4 days1015 mb / 30 In
201924°C / 75°F13°C / 55°F18°C / 64°F322 hours24.47 mm / 0.96 In4 days1014 mb / 30 In
202023°C / 74°F10°C / 49°F16°C / 62°F300 hours50.62 mm / 1.99 In5 days1019 mb / 31 In
202127°C / 81°F13°C / 55°F20°C / 67°F298 hours24.68 mm / 0.97 In4 days1013 mb / 30 In
202227°C / 80°F12°C / 54°F19°C / 66°F273 hours29.50 mm / 1.16 In4 days1015 mb / 30 In
202326°C / 78°F12°C / 53°F18°C / 64°F293 hours33.43 mm / 1.32 In2 days1014 mb / 30 In
202426°C / 78°F14°C / 57°F19°C / 67°F266 hours99.18 mm / 3.90 In4 days1014 mb / 30 In
202524°C / 75°F11°C / 53°F17°C / 63°F232 hours60.00 mm / 2.36 In2 days1016 mb / 30 In
202626°C / 79°F13°C / 55°F19°C / 66°F133 hours20.60 mm / 0.81 In9 days1013 mb / 30 In

Need more than one day of Boulder history?

Download historical weather for Boulder, or any other location, in CSV from January 2009 onwards. Ideal for research, insurance, energy, agriculture and machine-learning projects.

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Weather history near Boulder

Region

Colorado

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Boulder weather history: common questions

How far back does Boulder weather history go?

Hourly historical weather is available from 1 January 2009. Choose a date above, or pick a month at the top of the page for long-term averages.

Can I download Boulder historical weather as a file?

Yes. Buy historical weather data as daily or hourly CSV, yearly monthly averages or monthly climate averages. A free sample download is available.

Is there an API for historical weather?

Yes. The WeatherAPI.com History API returns hourly weather for any past date from 2010, as JSON or XML. Get a free API key.

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