Last updated: February 24, 2025
March in Boulder, United States, presents a diverse tapestry of weather, with temperatures ranging from a chilly -21°C (-5°F) to a pleasant 23°C (73°F). The average temperature settles around a brisk 2°C (35°F), creating a dramatic contrast perfect for embracing the change of seasons. With 62 mm (2.5 in) of precipitation over 11 days, expect some damp days amidst the emerging spring. The humidity level reaches a substantial 81%, accentuating the coolness in the air while nourishing the blooming landscape. Whether you're enjoying a brisk outdoor adventure or cozying up indoors, March offers a fulfilling mix of Boulder’s climate character.
In March, Boulder experiences a noticeable transition as winter begins to surrender to the early whispers of spring. The minimum temperatures hover around a brisk -21°C (-5°F), while the average climbs to a hopeful 2°C (35°F). This month showcases a marked increase in warmth, peaking at a delightful 23°C (73°F) on the warmer days, suggesting a joyful embrace of outdoor activities. Compared to the preceding months of February and January, when temperatures were at their coldest, March brings a refreshing change, inviting residents and visitors alike to relish the gradual thawing. As nature awakens, Boulder transforms into a vibrant landscape, reminiscent of the renewal that accompanies the arrival of spring.
In March, Boulder experiences a notable uptick in precipitation, with 62 mm (2.5 in) falling over 11 days—a significant increase from both January and February. This trend marks the onset of spring, as the city transitions from the drier winter months. The higher precipitation not only contributes to the lushness of the emerging landscape but also sets the stage for even wetter days ahead, as April follows closely with 68 mm (2.7 in) over just one additional day. Such patterns highlight March as a crucial month for replenishing local water sources, as the snowfall begins to melt and flows into the nearby rivers and reservoirs, making it a vital time for both nature and the community.
In March, humidity in Boulder, United States, settles at 81%, marking a gentle decline from the winter months, where January and February boast considerably higher levels at 88% and 87% respectively. This transitional dip signals the onset of spring, as the environment begins to dry out in preparation for the warmer months ahead. Following March, humidity continues to decrease, reaching its yearly low in July at 52%. This trend reflects a clear seasonal pattern; as temperatures rise from late spring into summer, the air becomes less saturated. By autumn, humidity begins to rise again, creating a cyclical rhythm that characterizes Boulder’s climate throughout the year.
In March, Boulder experiences a notable spike in UV exposure, with the UV Index reaching 9, categorizing it as very high. This increase marks a significant shift from the prior months, reflecting the transition into spring when sun intensity begins to climb. With a burn time of just 15 minutes, it's essential for residents and visitors alike to take sun safety seriously, as unprotected skin can quickly be at risk. This trend continues into April and May, where even higher UV levels demand increased caution. As the season progresses, it's clear that March serves as an important reminder of the evolving sunshine in Boulder, paving the way for the intense summer months ahead. For more detailed insights, check out the Boulder UV Index.
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As March arrives in Boulder, the days begin to lengthen, bringing an impressive 288 hours of sunshine—a notable increase from February's 237 hours. This significant surge marks the transition towards spring as the region shakes off winter's chill and embraces the warming rays of the sun. Following this trend, April promises even brighter days with 304 hours of sunshine on the horizon. The gradual climb in sunlight hours not only enhances the beauty of Boulder’s scenery but also invigorates the community, inviting outdoor activities and a renewed connection with nature. As the sun shines more brightly, it heralds the arrival of vibrant spring days filled with adventure and exploration.
In Boulder, the likelihood of sunny weather in March hovers around 50%, a slight dip compared to the more sunlit months that precede and follow it. As winter gives way to spring, this month transitions from the more consistent sunshine seen in January and February, both exceeding 50% likelihood. Following March, April sees a slight recovery, while the summer months bring notably higher chances of bright blue skies, peaking in August at an impressive 65%. Overall, while March may not boast the highest percentages of sunshine, it is a pivotal month that signals the start of more favorable weather ahead.
As March arrives in Boulder, daylight begins to extend, offering an invigorating shift from the winter months. With approximately 11 hours of sunlight, the days grow noticeably longer, signaling the approach of spring. This increase in daylight is part of a broader trend, as each month progresses from January's 9 hours to April's 13 hours, showcasing a significant leap toward the sunlit days of summer. This steady escalation culminates in the peak daylight duration of 14 hours during the peak summer months of June and July. March, therefore, serves as a delightful threshold, inviting residents to step outside and embrace the warm, rejuvenating energy of the season ahead.
March in Boulder offers a gentle embrace of wind, with an average speed of 2.5 m/s (6 mph), slightly lower than the previous months. This trend marks a subtle shift as the winter chill begins to recede; January and February maintain higher averages of 2.6 m/s and 2.8 m/s, respectively. As we transition into spring, the winds appear to calm further in April, dipping to 2.4 m/s (5 mph). Despite this decrease, the March breezes still carry a refreshing quality, hinting at the vibrant season ahead. The fluctuations in wind speed reflect the gradual awakening of the landscape, preparing Boulder's residents for the warmer days to come.
The weather in Boulder changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of March'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 comparing the weather between March and January, we see a noticeable difference in temperature and precipitation. March experiences a wider temperature range, with minimums dropping to -21°C (-5°F) and maximums reaching a pleasant 23°C (73°F), leading to an average of 2°C (35°F). In contrast, January is chillier, with temperatures averaging -3°C (26°F) and a maximum of only 15°C (59°F). Additionally, March has significantly more precipitation, totaling 62 mm (2.5 in) over 11 days, compared to January's 25 mm (1.0 in) across just 5 days. Despite the increased precipitation in March, January maintains a slightly higher humidity level at 88% compared to March's 81%. For more detailed insights, you can check out Boulder weather in January.
March generally experiences milder temperatures compared to February, with average highs reaching 2°C (35°F) in March, compared to February's average of -4°C (26°F). While March can see maximum temperatures climb to a pleasant 23°C (73°F), February's maximums are cooler at 20°C (69°F). Additionally, March tends to have more precipitation at 62 mm (2.5 in) over 11 days, compared to February's 36 mm (1.4 in) across 9 days. However, the humidity remains relatively high, with March showing 81% and February slightly higher at 87%. For more details on February weather, you can visit Boulder weather in February.
In March, temperatures in the region experienced a notable range, with minimums dropping to -21°C (-5°F) and maximums reaching up to 23°C (73°F), resulting in an average temperature of 2°C (35°F). The month saw precipitation totaling 62 mm (2.5 in) over 11 days, coupled with a relatively high humidity level of 81%. In contrast, April offered slightly milder temperatures, with a minimum of -17°C (2°F) and a maximum of 24°C (75°F), leading to an average temperature of 5°C (42°F). Precipitation increased marginally to 68 mm (2.7 in) over 12 days, while humidity decreased to 76%. For more details on what to expect, you can visit Boulder weather in April.
March and May present markedly different weather patterns. In March, temperatures can dip as low as -21°C (-5°F) with an average of 2°C (35°F) and can peak at 23°C (73°F). The month experiences 62 mm (2.5 in) of precipitation over 11 days, accompanied by a high humidity level of 81%. In contrast, May brings milder conditions, with minimum temperatures around -9°C (17°F) and an average of 10°C (50°F), while reaching maximums of 27°C (81°F). Rainfall increases to 134 mm (5.3 in) over 16 days, but humidity drops to 66%. For more detailed insights, you can check Boulder weather in May.
March and June present contrasting weather patterns. In March, temperatures can plummet to a chilling minimum of -21°C (-5°F), with an average of 2°C (35°F) and peaks reaching 23°C (73°F). The month experiences 62 mm (2.5 in) of precipitation over 11 days, accompanied by high humidity levels at 81%. In stark contrast, June offers a milder climate, with minimum temperatures of 3°C (37°F) and an average of 17°C (63°F), while the maximum can soar to 34°C (93°F). Precipitation increases slightly to 74 mm (2.9 in) over 14 days, but humidity drops to a more comfortable 58%. For more details about the weather in Boulder during June, visit Boulder weather in June.
March and July showcase stark contrasts in weather. March experiences frigid temperatures, with a minimum dipping as low as -21°C (-5°F) and an average temperature of about 2°C (35°F), while July offers much warmer conditions, with minimums around 7°C (45°F) and an average of 20°C (68°F). Precipitation is relatively similar, with March receiving 62 mm (2.5 in) across 11 rainy days compared to July's 71 mm (2.8 in) over a slightly higher 16 days. Humidity levels also differ significantly; March has a high humidity of 81%, making it feel chillier, whereas July's humidity drops to a comfortable 52%. For more details about the weather in July, you can check Boulder weather in July.
March and August present contrasting weather patterns. In March, temperatures can drop as low as -21°C (-5°F), with an average of 2°C (35°F) and highs reaching 23°C (73°F). The month is characterized by high humidity at 81% and moderate precipitation of 62 mm (2.5 in) over 11 days. In contrast, August offers a milder climate with minimum temperatures of 7°C (45°F), an average of 19°C (67°F), and maximum temperatures up to 33°C (91°F). While it experiences slightly more precipitation at 67 mm (2.7 in) over 13 days, the humidity decreases to 56%. For more details on August weather, you can visit Boulder weather in August.
March and September present contrasting weather patterns, demonstrating the transition between winter and fall. In March, temperatures can range dramatically from a chilly -21°C (-5°F) at night to a pleasant 23°C (73°F) during the day, with an average of 2°C (35°F). The month experiences significant precipitation of 62 mm (2.5 in) over about 11 days, accompanied by high humidity levels of 81%. In stark contrast, September boasts milder temperatures, with nighttime lows around -4°C (25°F) and daytime highs reaching up to 33°C (92°F), averaging 16°C (61°F). With less rainfall, totaling 42 mm (1.6 in) over just 8 days and humidity declining to 65%, September provides a more stable and comfortable climate. For more detailed insights, check out the Boulder weather in September.
March and October present contrasting weather conditions. In March, temperatures can range from a chilly minimum of -21°C (-5°F) to a relatively mild maximum of 23°C (73°F), with an average temperature of 2°C (35°F). This month experiences higher humidity at 81% and slightly more precipitation, totaling 62 mm (2.5 in) across 11 days. In comparison, October sees a less extreme temperature range, with a minimum of -20°C (-5°F) and a maximum of 26°C (79°F), and a higher average temperature of 7°C (45°F). The month is drier, receiving only 48 mm (1.9 in) of precipitation over about 7 days and a slight decrease in humidity to 76%. For a more detailed look at the October weather, check out Boulder weather in October.
March and November present similar average temperatures, both hovering around 2°C (35°F). However, March experiences a wider range, with minimum temperatures plummeting to -21°C (-5°F) and maximums soaring up to 23°C (73°F), while November's temperatures are slightly milder, with a minimum of -16°C (3°F) and a maximum of 22°C (71°F). Precipitation is more frequent in March, occurring on 11 days and totaling 62 mm (2.5 in), compared to November's 6 days of precipitation and a total of 30 mm (1.2 in). Humidity remains comparable in both months, with March at 81% and November at 82%. For a more detailed look at November weather specifics, check out Boulder weather in November.
March and December present contrasting weather patterns. In March, temperatures can fluctuate significantly, ranging from a minimum of -21°C (-5°F) to a maximum of 23°C (73°F), with an average of 2°C (35°F). This month also sees higher precipitation levels, totaling 62 mm (2.5 in) over approximately 11 days, with a humidity level of 81%. Conversely, December maintains colder conditions, with a narrower temperature range from -19°C (-1°F) to 19°C (67°F), and an average temperature of -2°C (29°F). Rainfall is less frequent in December, amounting to only 19 mm (0.8 in) over 4 days, alongside slightly higher humidity at 89%. For more details, you can check Boulder weather in December.
As winter slowly yields to spring, March in Boulder presents a unique climate profile that sets it apart from the preceding months. While the maximum temperatures begin to rise, averaging around a mild 2°C during the day, nighttime can bring a sharp chill, reaching lows of -21°C. This month also experiences increased precipitation, with frequent light showers that contribute to a total of 62 mm over about 11 days. The atmosphere tends to feel more humid than in the drier winter months, averaging around 81% humidity, which, combined with the fluctuating temperatures, showcases the transitional nature of March weather in Boulder. For a deeper dive into seasonal variations, explore more at Boulder Climate.