Last updated: April 22, 2025
May in Ottawa presents a dynamic blend of springtime warmth and occasional cool spells. The maximum temperature soars to a balmy 35°C (95°F), while the average settles at a comfortable 13°C (56°F), reflecting the transition into the warmer months. However, residents and visitors should be prepared for cooler days as temperatures can dip to a crisp -3°C (26°F). With 117 mm (4.6 in) of precipitation spread over 14 days, spring showers are common, contributing to the city's lush greenery. The humidity level hovers around 75%, creating a refreshing yet moist atmosphere perfect for outdoor activities. Enjoy the vibrant sights and sounds of Ottawa as nature awakens in May!
May in Ottawa heralds a delightful transition into warmer days, with temperatures rising significantly from the chill of winter. The month kicks off with minimums of -3°C (26°F) but quickly warms to an average of 13°C (56°F), making it a refreshing time for outdoor activities. With maximum temperatures soaring to a balmy 35°C (95°F) at times, May showcases a remarkable range that reflects the city's shift towards summer. This rollercoaster of temperatures not only brings the promise of blooming landscapes but also indicates the potential for warmth, as Ottawa prepares to leave the cold months behind and embrace the sunny season ahead.
May in Ottawa marks the peak of spring precipitation, with an average of 117 mm (4.6 in) falling over 14 days. This increase in rainfall compared to the previous months signals a transition into the lushness of summer. Notably, May's precipitation slightly surpasses April's total of 112 mm (4.4 in), reflecting a trend of rising moisture as the city shakes off the last remnants of winter. This uptick in rainfall sets the scene for vibrant blooms and greener landscapes, creating a refreshing backdrop for outdoor activities. As Ottawa embraces warmer temperatures, the consistent drizzle often heralds the emergence of summer's vibrant flora, establishing May as a month of lively transformation.
In May, Ottawa begins to shake off the chill of winter, and the humidity levels reflect this transition, dropping to 75%. This noticeable decrease from the higher percentages of the preceding months indicates the arrival of warmer temperatures and more comfortable conditions. As spring unfolds, the city's atmosphere becomes a bit drier compared to the heavy, moisture-laden air of January and February, which linger at a humid 93%. Following May, the humidity continues its trend downward, reaching a refreshing low of 68% in June, hinting at the onset of summer. This gradual decline in humidity from the dampness of spring to the crispness of summer makes May a delightful month, offering a balanced blend of warmth and comfort for residents and visitors alike.
As May arrives in Ottawa, the UV Index takes a noticeable leap, reaching a striking 9, which designates it within the very high exposure category. This means that the risk of harm from unprotected sun exposure is significant, with a quick burn time of only 15 minutes. Following a gradual increase from the more moderate values seen in January through March, this uptick signals a transition into the summer months where UV radiation intensifies. Visitors and residents alike should take precautionary measures, such as wearing sunscreen and protective clothing, to enjoy the sunny days safely. For more information on UV levels throughout the year, check the detailed insights at Ottawa UV Index.
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In Ottawa, May marks a brilliant turning point in the annual sunshine journey, boasting an impressive 279 hours of sunshine. This surge follows the gradual increase from March and April, where the sunlight hours steadily rose to 235 and 227, respectively. As spring unfurls its vibrant colors, the city basks in longer days and warmer temperatures, setting the stage for a radiant summer ahead. Notably, the momentum continues into June, which captures the sun's essence with 314 hours, leading into the peak of summer in July with 348 hours. The transition from the chill of winter to the warm embrace of May not only brightens the skyline but invigorates the spirit, making it a cherished month for outdoor adventures and community gatherings.
As spring blossoms into May in Ottawa, the likelihood of sunny weather rises significantly, matching the warmer months with a 44% chance of sunshine. This marks a notable leap from the chilly winter months, where January and February hover around only 27% and 35% respectively. Despite May's consistency in sun probability, it stands out against the backdrop of April's 36%, suggesting that the city is finally shaking off the clouds of early spring. Just as nature awakens, so too does the sun, providing Ottawans with the promise of brighter days ahead—a perfect time for outdoor activities and enjoying the beauty the season has to offer.
As spring unfolds in Ottawa, May heralds a delightful increase in daylight, offering 14 hours of sunshine to energize outdoor activities and gatherings. This trend marks a significant leap from just 11 hours in March and reflects the steady progression toward the longest days of summer, with June peaking at 15 hours of daylight. Following May's vibrant atmosphere, the daylight slowly begins to wane, tapering off to 12 hours in September and eventually retreating back to 9 hours by November. This cycle not only highlights the beauty of changing seasons but also the gradual shift in light that influences daily life in this lively capital.
In May, Ottawa experiences a steady average wind speed of 2.9 m/s (7 mph), maintaining the same gentle breeziness seen in the preceding months of January and February. This consistency suggests a calm start to the summer season, which typically sees slightly more wind in the following months. Notably, as the city transitions into June, there's a slight uptick to 3.1 m/s (7 mph), indicating that spring's moderate winds pave the way for the more dynamic patterns of summer. Overall, the data reflects a tranquil atmosphere in May, with winds that are neither too strong nor too weak, creating the perfect backdrop for outdoor activities as nature comes alive.
The weather in Ottawa changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of May's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Ottawa and find detailed weather information for every month.
In comparing the weather of May and January, we see a significant contrast in temperatures and conditions. May experiences a broad temperature range, with minimums around -3°C (26°F) and maximums reaching up to 35°C (95°F), averaging a pleasant 13°C (56°F). The month also brings moderate rainfall, with precipitation totaling 117 mm (4.6 in) over approximately 14 days and a humidity level of 75%.
In stark contrast, January is much colder, starting with minimum temperatures that plummet to -32°C (-26°F) and only rising to a maximum of 10°C (50°F), averaging -9°C (16°F). This winter month sees less precipitation at 76 mm (3.0 in) spread over 9 days, coupled with higher humidity at 93%. For a closer look at January's chilly conditions, you can check Ottawa weather in January.
The weather in May and February in Ottawa demonstrates a stark contrast in temperatures and conditions. In May, temperatures can range from a chilly minimum of -3°C (26°F) to a warm maximum of 35°C (95°F), with an average around 13°C (56°F). This month also sees a notable amount of precipitation, totaling 117 mm (4.6 in) over approximately 14 days, with a humidity level of 75%. In comparison, February presents a much colder picture, with temperatures dropping as low as -27°C (-16°F) and averaging -8°C (18°F), peaking at 11°C (53°F). The month experiences less precipitation at 81 mm (3.2 in) across about 12 days, although the humidity is higher at 93%. For more detailed insights, check out Ottawa weather in February.
May and March present strikingly different weather patterns. In March, temperatures range from a chilly minimum of -24°C (-12°F) to a maximum of 20°C (69°F), with an average lingering around -3°C (27°F). The month experiences a total of 87 mm (3.4 in) of precipitation over 12 days, coupled with high humidity at 86%. In contrast, May boasts a much warmer climate, with minimum temperatures around -3°C (26°F) and highs soaring to 35°C (95°F), averaging a comfortable 13°C (56°F). This month experiences a higher total precipitation of 117 mm (4.6 in) spread over 14 days, although humidity slightly decreases to 75%. For further details about March weather, you can check Ottawa weather in March.
In comparison to April, May experiences a noticeable rise in temperatures, with averages soaring from 5°C (42°F) in April to 13°C (56°F) in May. The maximum temperature also increases significantly, peaking at 35°C (95°F) in May, compared to April's maximum of 27°C (81°F). Precipitation levels are fairly similar, with May recording 117 mm (4.6 in) over 14 days, slightly surpassing April's 112 mm (4.4 in) over 12 days. Humidity levels also decrease slightly from April's 82% to May's 75%, indicating a shift towards drier conditions. For more details on April's weather, visit Ottawa weather in April.
In comparing the weather between May and June, we see notable differences in temperature and humidity levels. May experiences a broader temperature range, with minimums as low as -3°C (26°F) and maximums soaring to 35°C (95°F), resulting in an average of 13°C (56°F). Conversely, June has a milder minimum temperature of 2°C (36°F) and a maximum of 32°C (91°F), bringing the average up to a more comfortable 18°C (65°F). Additionally, May is characterized by higher humidity at 75%, compared to June’s lower humidity of 68%. Precipitation levels also see a slight decrease, with May receiving 117 mm (4.6 in) over 14 days, while June records 98 mm (3.9 in) across 13 days. For more specific weather details, you can check Ottawa weather in June.
May and July showcase distinct weather patterns, highlighting the transition from spring to summer. In May, temperatures range from a chilly minimum of -3°C (26°F) to a warm maximum of 35°C (95°F), with an average temperature of 13°C (56°F). This month sees significant precipitation of 117 mm (4.6 in) over 14 days and high humidity at 75%. In contrast, July offers a milder minimum temperature of 8°C (47°F) and a summer average of 21°C (70°F), while also reaching a maximum of 35°C (96°F). Precipitation in July is slightly lower at 114 mm (4.5 in), with rain occurring over 12 days, and humidity decreases to 69%. For more detailed information, check out Ottawa weather in July.
May and August showcase distinct differences in weather patterns. In May, temperatures can swing dramatically, with minimums dipping to -3°C (26°F) and maximums peaking at 35°C (95°F), resulting in an average temperature of 13°C (56°F). This month also experiences higher precipitation, with around 117 mm (4.6 in) falling over 14 days, coupled with humidity levels of 75%. In contrast, August offers a more stable climate, with minimum temperatures at 7°C (45°F) and maximums reaching 32°C (89°F), leading to an average of 20°C (68°F). Precipitation decreases to 94 mm (3.7 in) over 13 days, and humidity drops to 67%. For a detailed look at August weather patterns, you can visit Ottawa weather in August.
May and September exhibit distinct weather characteristics, influencing outdoor activities and lifestyle. In May, temperatures range from a chilly -3°C (26°F) at night to a warm average of 13°C (56°F) during the day, peaking at an impressive 35°C (95°F). This month also experiences relatively high precipitation, with 117 mm (4.6 in) falling over 14 days, resulting in a humidity level of 75%. In contrast, September offers a milder climate with nighttime lows of around 0°C (31°F) and an average of 15°C (60°F), alongside maximum temperatures reaching 32°C (90°F). The month sees less rain, totaling 79 mm (3.1 in) across 11 days, and slightly lower humidity at 72%. For a detailed look at September weather, visit Ottawa weather in September.
May and October exhibit notable differences in weather patterns. In May, temperatures range from a chilly -3°C (26°F) at night to a warm 35°C (95°F) during the day, with an average of 13°C (56°F). The month sees about 117 mm (4.6 in) of precipitation spread over 14 days and has a humidity level of 75%. In contrast, October temperatures dip lower, with nights averaging -6°C (22°F) and daytime highs reaching 27°C (81°F), averaging around 9°C (48°F). Precipitation increases slightly to 132 mm (5.2 in) over 12 days, while humidity rises to 83%. This shift reflects the transition from the warmth of spring to the cooler, more humid autumn months. For a detailed look at weather specifics, check out Ottawa weather in October.
May and November present stark contrasts in weather. In May, temperatures range from a chilly -3°C (26°F) at night to a warm 35°C (95°F) during the day, with an average of 13°C (56°F). The month is characterized by relatively high humidity at 75% and 117 mm (4.6 in) of precipitation over about 14 days, making it a time when spring blooms flourish. In contrast, November sees much colder temperatures, with nighttime lows plunging to -19°C (-2°F) and daytime highs reaching a mild 22°C (71°F), resulting in an average of just 0°C (33°F). The precipitation is slightly less, at 97 mm (3.8 in) over the same number of days, but humidity is higher at 88%, creating a damp chill in the air. For more detailed insights on the weather patterns, check Ottawa weather in November.
May and December present contrasting weather conditions in terms of temperature and overall climate. In May, temperatures range from a chilly -3°C (26°F) to a warm 35°C (95°F), with an average of 13°C (56°F). This month sees around 117 mm (4.6 in) of precipitation over approximately 14 days, and the humidity levels hover around 75%. In stark contrast, December is much colder, with temperatures varying from a frigid -29°C (-20°F) to a mild 14°C (58°F), averaging -5°C (22°F). The precipitation in December is lower at 80 mm (3.2 in), occurring over about 12 days, and the humidity is higher at 89%. For more details on December weather, check out Ottawa weather in December.
As spring reaches its peak, May in Ottawa brings a delightful shift in weather, contrasting sharply with the chill of earlier months. With an average temperature that begins to warm up significantly, residents and visitors can finally enjoy outdoor activities amidst blooming flowers. While occasional rain showers can be expected, with about half the month seeing precipitation, the increased humidity gives the air a refreshing feel. Overall, May serves as a beautiful transition into summer that stands out from the previous months' lingering cold. For more insights into rainfall and temperature trends throughout the year, check out Ottawa Climate.