Last updated: February 24, 2025
October in Boulder, United States, showcases a striking contrast in weather as autumn unfolds. Temperatures range from a comfortable maximum of 26°C (79°F) to a brisk minimum of -20°C (-5°F), offering both warm days and chilly nights. The city experiences an average temperature of 7°C (45°F), perfect for enjoying the vibrant fall foliage. With 48 mm (1.9 in) of precipitation over 7 days, October brings a mix of refreshing moisture, contributing to the lush landscape. The humidity level hovers around 76%, adding a crisp feel to the air. Embrace the beauty and variability of Boulder’s October weather!
In Boulder, Colorado, October marks a distinct transition as summer's warmth gives way to autumn's chill. This month typically sees minimum temperatures dropping to around -20°C (-5°F), with an average hovering at a brisk 7°C (45°F). While the maximum can still reach a comfortable 26°C (79°F), the overall trend clearly points towards cooler days and frigid nights. As fall deepens, the marked shift from September’s milder 16°C (61°F) average underscores the approach of winter, making October a time when sweater weather really starts to take hold. The crisp air and slightly shorter days invite residents and visitors alike to embrace the seasonal change, with the vibrant foliage transforming the landscape into a splendid tapestry of colors.
In October, Boulder experiences a notable transition as the fall season sets in, bringing with it an average precipitation of 48 mm (1.9 in) over 7 days. This represents a slight increase from the drier September, which saw just 42 mm but over a longer span of 8 days. October's rainfall is part of a gradual decline following the summer months, marked by significantly higher totals in May (134 mm) and April (68 mm). As temperatures begin to dip, the shifting patterns in precipitation hint at the forthcoming winter, with each autumn month generally yielding less rain than its spring or summer counterparts. This blend of decreased rainfall and cooler weather fuels the vibrant colors of fall foliage, making October a picturesque month in Boulder, where every drop of rain becomes a vital part of the seasonal transition.
In October, Boulder experiences a noticeable transition in humidity levels, with an average of 76% that reflects the shift from the drier summer months to the moisture-rich fall season. This moderate humidity is a slight increase from the 65% recorded in September, signaling the onset of cooler temperatures and the approaching winter. It's intriguing to observe that October's humidity aligns more closely with the spring months, notably April and March, than with the summer peak of 52% in July. As the air grows crisp and the days shorten, Boulder’s October humidity creates a refreshing ambiance that complements the vibrant autumn foliage.
As October rolls into Boulder, the UV Index shows a notable decrease, registering at 7, which falls into the high exposure category. This marks a shift from the extreme levels experienced during the summer months, where indices peaked at 12 in both June and July, resulting in a burn time as short as 10 minutes. With the days getting shorter and the sun's intensity waning, October allows for more extended exposure times of about 25 minutes before burning occurs, providing a somewhat safer opportunity to enjoy the outdoors. However, it’s still crucial to remain vigilant; skin protection is still recommended during these autumn outings. To explore more about this seasonal trend and stay updated, visit Boulder UV Index.
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October in Boulder, United States, brings a brisk yet beautiful transition into fall, with an impressive 274 hours of sunshine illuminating the landscape. This month sees a notable dip compared to the sun-drenched summer, particularly from the peak of 378 hours in July, but it still outshines the darker winter months ahead. As the trees don their vibrant autumn coats, the sunshine invites residents and visitors alike to enjoy the crisp air and scenic views, making October a perfect blend of warmth and coolness. (As the year progresses, the gradual decrease in sunlight becomes evident, yet October maintains a charm fueled by its golden rays.)
As October arrives in Boulder, the likelihood of sunny weather remains notable, with a 63% chance of sunshine. This figure reflects an upward trend from the earlier months, where the chances consistently wavered around the mid-50s. Interestingly, October stands out as a month of transition, sandwiched between the warm summer days of August and September, which boast chances of sun at 65% and 69% respectively. The sunny disposition of October paves the way for vibrant fall foliage and outdoor activities, making it an ideal time to enjoy the season before winter sets in. Overall, with its relatively high probability of clear skies, October continues the trend of sunny weather into the fall, providing ample opportunity to soak up the sun.
As October rolls into Boulder, the days begin to shorten, settling at an average of 11 hours of daylight. This transition marks a gradual decline after the peak summer months, where daylight stretched luxuriously to 14 hours in June through July. The month's sunlight feels crisp and invigorating, as it follows a summer sun-drenched pattern, balancing beautifully against the backdrop of vibrant fall foliage. While the daylight hours are still ample enough for outdoor adventure, they signal the impending approach of winter, as November and December will offer even shorter days, returning to just 9 hours. This rhythm of increasing and decreasing daylight not only shapes our days but also enhances the rich tapestry of seasonal experiences in Boulder.
As October graces Boulder, the gentle winds begin to shift, averaging 2.4 m/s (5 mph), a slight increase from the summer's calm breezes. This change marks a subtle transition as the milder autumn air starts to envelop the city, contrasting with the brisk gusts that are on the horizon for November and December, which see wind speeds rising to 2.9 m/s (6 mph) and 3.0 m/s (7 mph) respectively. The trend reflects a gradual escalation in wind intensity as the year draws to a close, inviting residents to embrace the crisp air while preparing for the bolder gusts of winter. The October winds in Boulder remain a soft reminder of the seasonal shift, fostering a sense of anticipation for the beauty that each month brings.
The weather in Boulder changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of October's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Boulder and find detailed weather information for every month.
In October, temperatures can vary significantly, from a chilly minimum of -20°C (-5°F) to a warm maximum of 26°C (79°F), with an average temperature around 7°C (45°F). This month experiences about 48 mm (1.9 inches) of precipitation over approximately 7 days, with a humidity level of 76%.
In contrast, January typically sees colder conditions, with minimum temperatures dropping to -24°C (-12°F) and a maximum of 15°C (59°F), yielding an average temperature of -3°C (26°F). Precipitation is lower in January at about 25 mm (1.0 inch) over 5 days, accompanied by higher humidity at 88%. For a deeper insight into the specifics of January weather, you can visit Boulder weather in January.
October and February showcase significant differences in weather patterns. October experiences milder temperatures, ranging from a minimum of -20°C (-5°F) to a maximum of 26°C (79°F), with an average of 7°C (45°F). It also sees about 48 mm (1.9 in) of precipitation over seven days and has a humidity level of 76%. In contrast, February is notably colder, with temperatures plunging to a minimum of -26°C (-14°F) and averaging -4°C (26°F), peaking at 20°C (69°F). February tends to be slightly drier with 36 mm (1.4 in) of precipitation over nine days, although the humidity is higher at 87%. For more details on February weather, you can check Boulder weather in February.
In October, the weather in Boulder showcases a notable range, with temperatures fluctuating from a minimum of -20°C (-5°F) to a pleasant maximum of 26°C (79°F), and an average of around 7°C (45°F). This month sees about 48 mm (1.9 in) of precipitation over approximately 7 days, with humidity levels averaging 76%. In contrast, March experiences slightly cooler temperatures, with minimums around -21°C (-5°F), an average of 2°C (35°F), and a maximum of 23°C (73°F). The precipitation is slightly higher at 62 mm (2.5 in) over about 11 days, accompanied by a higher humidity level of 81%. For more details, check out Boulder weather in March.
October and April exhibit distinct weather patterns, with notable differences in temperature and precipitation. In October, the temperature ranges from a minimum of -20°C (-5°F) to a pleasant maximum of 26°C (79°F), averaging around 7°C (45°F). The month sees about 48 mm (1.9 in) of precipitation over an average of 7 days, maintaining a consistent humidity level of 76%. In contrast, April has a slightly lower average temperature of 5°C (42°F), with similar minimum and maximum temperatures ranging from -17°C (2°F) to 24°C (75°F). April also experiences more precipitation, totaling 68 mm (2.7 in) over approximately 12 days, while humidity remains the same at 76%. For more details on April weather, check out Boulder weather in April.
When comparing October and May weather, several notable differences emerge. October typically features a wider range of temperatures, with a minimum of -20°C (-5°F) and a maximum of 26°C (79°F), leading to an average temperature of 7°C (45°F). In contrast, May's temperatures are milder, ranging from a minimum of -9°C (17°F) to a maximum of 27°C (81°F), with an average of 10°C (50°F). Precipitation also varies significantly; October sees 48 mm (1.9 in) over 7 days, while May is much wetter with 134 mm (5.3 in) over 16 days, contributing to a lower humidity of 66% compared to October’s 76%. For more specific insights into May weather patterns, you can visit Boulder weather in May.
When comparing the weather in October and June, notable differences emerge. October features a broader temperature range, with overnight lows dipping to -20°C (-5°F) and daytime highs averaging around 7°C (45°F) but occasionally reaching up to 26°C (79°F). In contrast, June presents a milder climate, with minimum temperatures of 3°C (37°F) and maximum temperatures averaging 34°C (93°F), leading to a generally more comfortable warm weather experience. Precipitation is also higher in June, with 74 mm (2.9 in) across 14 days, compared to October's 48 mm (1.9 in) over just 7 days, though October's humidity is notably higher at 76% versus June's 58%. For a more detailed look at June weather, you can check Boulder weather in June.
October weather is characterized by a notable drop in temperatures compared to July, with average highs of only 26°C (79°F) compared to July's peak of 34°C (93°F). The min temperatures also reflect this seasonal change, plunging down to -20°C (-5°F) in October, whereas July starts at a much milder 7°C (45°F). Additionally, October experiences higher humidity at 76%, compared to July's 52%, creating a chillier feel despite the somewhat warmer daytime temperatures in late summer. Precipitation is more frequent in July, with rain on 16 days totaling 71 mm (2.8 in), while October sees less rainfall over 7 days, amounting to 48 mm (1.9 in). For more information on July weather, you can check Boulder weather in July.
In comparing the weather conditions of October and August, significant variations emerge. October enjoys a wider temperature range, with minimums dipping to -20°C (-5°F) while the maximum can reach 26°C (79°F), resulting in an average of 7°C (45°F). The month experiences moderate rainfall, totaling 48 mm (1.9 in) over approximately 7 days, and features a higher humidity level at 76%. Conversely, August presents warmer temperatures with a minimum of 7°C (45°F), an average of 19°C (67°F), and maximums soaring up to 33°C (91°F). Precipitation is slightly higher at 67 mm (2.7 in) across 13 days, alongside a lower humidity level of 56%. For a detailed look at August's weather, you can visit Boulder weather in August.
In comparing the weather patterns of September and October, a notable shift occurs. September boasts milder temperatures, with an average of 16°C (61°F) and highs reaching up to 33°C (92°F), while October sees a significant drop, averaging around 7°C (45°F) and peaking at 26°C (79°F). Precipitation levels are relatively similar, with September receiving 42 mm (1.6 in) over 8 days compared to October's 48 mm (1.9 in) across 7 days, although the humidity is higher in October at 76% compared to September's 65%. For a more detailed look at September weather, visit Boulder weather in September.
In October, temperatures fluctuate significantly, with a minimum of -20°C (-5°F) and a maximum reaching 26°C (79°F), resulting in an average of 7°C (45°F). The month receives about 48 mm (1.9 in) of precipitation over 7 days, and humidity levels sit at 76%. In contrast, November sees a slight drop in overall temperatures, with a minimum of -16°C (3°F) and a maximum of 22°C (71°F), averaging at 2°C (36°F). Precipitation decreases to 30 mm (1.2 in) over 6 days, while humidity rises to 82%. For more details on November weather specifics, you can visit Boulder weather in November.
October and December present contrasting weather conditions, with October showcasing a wider temperature range. In October, temperatures can dip as low as -20°C (-5°F) and peak at 26°C (79°F), averaging around 7°C (45°F). The month experiences about 48 mm (1.9 in) of precipitation over 7 days, accompanied by a humidity level of 76%. In contrast, December's temperatures are generally colder, with a minimum of -19°C (-1°F) and a maximum of 19°C (67°F), leading to an average of -2°C (29°F). Precipitation in December is significantly lower at 19 mm (0.8 in) over just 4 days, though humidity rises to 89%. For further details about the weather in December, you can check Boulder weather in December.
As October sets in, Boulder transforms with cooler temperatures and a noticeable increase in humidity, making it distinct from the warmer, drier summer months. With highs occasionally reaching 26°C and lows dipping to nearly freezing, residents and visitors alike experience a broader temperature range. This month also brings increased precipitation, with about 48 mm falling over roughly a week, creating a refreshing contrast to the arid conditions typical of the preceding summer. As the autumn leaves begin to change and mornings become brisk, the overall weather highlights Boulder’s unique charm during this transitional season. For more insights into Boulder’s climate, visit Boulder Climate.