Last updated: April 22, 2025
In Saint John, Canada, May brings a refreshing change as temperatures rise, boasting a maximum of 20°C (68°F) and an average of 9°C (48°F), while dipping to a cooler minimum of 1°C (33°F). Known for its lush landscapes and vibrant atmosphere, the month is also characterized by 117 mm (4.6 in) of precipitation over approximately 12 days, contributing to the region's rich greenery. With humidity levels averaging at 78%, the air is filled with a refreshing dampness, enhancing the experience of spring's beauty in this charming coastal city.
As May arrives in Saint John, Canada, the transition from winter to spring becomes unmistakably evident. With minimum temperatures averaging 1°C (33°F) and peaking at a pleasant 20°C (68°F), this month signals a welcome warmth after the long, icy grip of winter. The average temperature of 9°C (48°F) reflects a significant increase from the preceding months, paving the way for outdoor activities and blooming landscapes. As daylight hours expand and frosty nights diminish, residents and visitors alike can relish in the joy of mild weather and the vibrant resurgence of nature during this enchanting spring month.
May in Saint John, Canada, brings a refreshing average precipitation of 117 mm (4.6 in) over roughly 12 days of rain, marking a continuation of the spring wetness following April's higher total of 129 mm (5.1 in). This slight drop in rainfall signals a transition as the region approaches summer, while still comfortably above the drier months of July and August, which typically see averages around 92 mm (3.6 in) and 89 mm (3.5 in), respectively. The consistent moisture levels throughout the spring months highlight Saint John's reliance on precipitation to support its lush landscapes, serving as a reminder of the natural cycles that influence its climate.
In Saint John, Canada, the month of May brings a noticeable dip in humidity levels, falling to 78%—a welcome relief as the city transitions into summer. This decrease highlights a gradual trend of declining humidity from the peak winter months, where percentages hover around the 83-84% mark in January and February, to more moderate figures in late spring. While the humidity begins to rise again by June, it is clear that May serves as a pivotal moment, offering residents a brief interlude of refreshing air before the summer months bring back the stickier conditions of 82-84%. This fluctuation not only enhances the region's charm but also makes May an inviting time to explore the beautiful coastal landscape.
As the sun shines brighter in May, Saint John sees a notable leap in the UV Index, reaching a striking 9—a level categorized as very high. This significant increase from the previous months marks a shift in outdoor conditions, reducing burn time to just 15 minutes. From April's 7 to May's 9, this sharp rise signals the onset of summer, urging locals and visitors alike to take precautions against sun exposure. The trend continues into June, where the UV Index peaks at 10. In comparison, the winter months show a stark contrast with low UV ratings, emphasizing the importance of being sun-smart as warmer days approach. For more detailed insights on UV levels throughout the year, check out the Saint John UV Index.
UV Risk Categories
As May unfolds in Saint John, Canada, residents eagerly embrace the blossoming warmth with an impressive 280 hours of sunshine. This marks a significant uptick from the earlier months, with March and April basking in 242 and 228 hours, respectively. The trend of increasing daylight becomes even more pronounced as summer approaches, with June and July each boasting over 300 hours of sun. This steady rise, from the dimmer days of January's 127 hours to May's golden glow, sets the stage for vibrant outdoor activities and community gatherings. The transition into late spring highlights not just the sunshine, but also the energy and optimism that often accompany this beautiful time of year in Saint John.
In Saint John, Canada, the likelihood of sunny weather experiences fascinating fluctuations throughout the year. As spring transitions into summer, May captures a 39% chance of sunshine, notably higher than the dreary April conditions, which languish at 28%. This trend hints at the rejuvenating potential of late spring, as the sun begins to peek through more frequently after the long, colder months. Interestingly, while May boasts a promising forecast, it still falls short of the sunnier months of September and October, where the chances rise to 42% and 41% respectively. Thus, while May may not guarantee a sun-drenched experience, it certainly opens the door to brighter days ahead, inviting residents and visitors to embrace the freshness of the season.
As spring transitions into summer, Saint John, Canada experiences a notable increase in daylight duration, culminating in May with a generous 14 hours of sunlight. This burst of light follows a progressive rise from just 9 hours in January to 10 hours in February, and gradually escalating to 13 hours by April. The trend highlights a significant shift as the days lengthen, paving the way for the longest days of the year in June and July, where daylight peaks at 15 hours. After the summer solstice, daylight begins to wane, tapering off to 13 hours in August before descending back to 9 hours by November. This rhythmic cycle of light not only enhances the region's natural beauty but also invites residents and visitors alike to embrace the outdoor activities that flourish in the brighter months.
In May, Saint John, Canada, experiences a gentle lull in the winds, with an average speed of 4.8 m/s (11 mph). This marks a notable decrease from the blustery conditions of previous months, such as March's peak of 6.2 m/s (14 mph). As spring unfolds, the transition into warmer months is characterized by more moderate breezes, which can be perfect for outdoor activities and enjoying the blossoming scenery. Following May, the wind speeds slightly increase again in June to 4.9 m/s (11 mph), suggesting a pattern where early summer may bring more favorable conditions for sailing and seaside strolls, continuing a seasonal rhythm that balances between robust winter gusts and the calmer summer air.
The weather in Saint John 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 Saint John and find detailed weather information for every month.
In a striking contrast to January, May welcomes milder temperatures, with average highs reaching up to 20°C (68°F) compared to January's frigid max of 13°C (56°F). While January experiences chilly minimums, dipping to -22°C (-8°F), May's lowest temperature is a more bearable 1°C (33°F). Although both months see significant precipitation—117 mm (4.6 in) in May and 107 mm (4.2 in) in January—May's rainfall is spread over 12 days, allowing for more pleasant outdoor conditions. January, with its higher humidity at 83%, feels notably colder, whereas May's humidity of 78% complements its warmer climate. For more detailed January weather patterns, you can visit Saint John weather in January.
In comparing the weather of May and February, we notice significant differences in temperature and humidity. May experiences a much milder climate, with average temperatures ranging from a minimum of 1°C (33°F) to a maximum of 20°C (68°F), while February is considerably colder, with temperatures ranging from -20°C (-4°F) to a maximum of 10°C (50°F). Despite both months having similar precipitation levels—117 mm (4.6 in) in May and 112 mm (4.4 in) in February—the type of precipitation varies greatly, with February's chill often leading to snow or ice. Furthermore, the humidity is slightly lower in May at 78% compared to February’s 84%, contributing to the overall perceivable warmth in late spring. For more details on February's weather, check out Saint John weather in February.
In comparing the weather between May and March, it’s clear that May offers significantly warmer temperatures, with an average of 9°C (48°F) compared to March's average of -1°C (31°F). While March experiences colder nights, dipping as low as -17°C (2°F), May boasts milder nighttime temperatures, starting from a minimum of 1°C (33°F). Precipitation is also more frequent in May, with 117 mm (4.6 in) over 12 days, compared to 88 mm (3.5 in) over 10 days in March. Furthermore, humidity levels are slightly lower in May at 78%, compared to 82% in March. For a more detailed look at March weather, visit Saint John weather in March.
In comparing the weather of April and May, May emerges as a warmer month, with average temperatures significantly higher, ranging from a minimum of 1°C (33°F) to a maximum of 20°C (68°F). In contrast, April records lower temperatures, with a minimum of -5°C (23°F) and a maximum of 13°C (55°F). Both months are quite wet, with May receiving 117 mm (4.6 in) of precipitation over 12 days, while April has slightly more precipitation at 129 mm (5.1 in) over 13 days. Humidity levels are relatively similar, with April at 80% and May at 78%. For a closer look at April’s weather specifics, check out Saint John weather in April.
May and June showcase a gradual warming trend in weather conditions. In May, temperatures range from a chilly minimum of 1°C (33°F) to a pleasant maximum of 20°C (68°F), with an average temperature of 9°C (48°F). The month also sees 117 mm (4.6 in) of precipitation over 12 days, accompanied by humidity levels around 78%. In contrast, June offers a mild increase in temperatures, with minimums of 4°C (39°F) and maximums reaching 21°C (71°F), resulting in an average temperature of 13°C (56°F). Precipitation slightly decreases to 110 mm (4.3 in) over 11 days, while humidity rises to 82%. For more detailed information, you can check Saint John weather in June.
May and July present quite different weather patterns. In May, temperatures start chilly with a minimum of 1°C (33°F) and reach an average high of 20°C (68°F), accompanied by significant precipitation of 117 mm (4.6 in) over 12 days. The humidity level sits at 78%, making the air feel quite damp. In contrast, July experiences milder temperatures, with a minimum of 11°C (51°F) and an average maximum of 22°C (72°F). It also sees less rainfall at 92 mm (3.6 in) over 13 days, but the humidity rises to 84%, adding a touch of mugginess to the summer days. For those interested in a deeper look at what July has to offer, you can explore more here: Saint John weather in July.
May and August exhibit distinct weather characteristics that reflect the transition from spring to late summer. In May, temperatures range from a chilly minimum of 1°C (33°F) to a pleasant maximum of 20°C (68°F), with an average of 9°C (48°F). Conversely, August boasts a milder climate, with minimum temperatures beginning at 11°C (53°F) and maximum temperatures reaching 23°C (74°F), resulting in a comfortable average of 17°C (63°F). While May experiences a higher amount of rainfall, totaling 117 mm (4.6 in) over 12 days, August is comparatively drier with 89 mm (3.5 in) of precipitation over 10 days. Humidity levels are relatively high in both months, at 78% in May and slightly higher at 82% in August. For more detailed insights on weather patterns, you can check Saint John weather in August.
May and September offer distinct weather experiences, showcasing a transition from spring to autumn. In May, temperatures range from a chilly 1°C (33°F) at night, averaging around 9°C (48°F) during the day, and peaking at 20°C (68°F). This month sees moderate rainfall, with precipitation totaling 117 mm (4.6 in) over about 12 days and an average humidity of 78%. In contrast, September brings a milder climate with nighttime lows around 7°C (45°F), an average daytime temperature of 15°C (59°F), and highs reaching 22°C (73°F). Although slightly less rain falls than in May, with 108 mm (4.3 in) over 10 days, the humidity increases to 82%. For more insights on September conditions, check out Saint John weather in September.
May and October present a contrast in weather as spring transitions to autumn. In May, temperatures range from a chilly minimum of 1°C (33°F) to a pleasant maximum of 20°C (68°F), with an average of 9°C (48°F). The month experiences about 117 mm (4.6 in) of precipitation over 12 days, accompanied by a humidity level of 78%. In comparison, October sees slightly cooler temperatures, with a minimum of 0°C (33°F) and a maximum of 19°C (67°F), but a higher average of 11°C (52°F). Precipitation increases slightly to 123 mm (4.8 in), also spread over 12 days, and humidity rises to 82%. This slight uptick in moisture and cooler temperatures marks the transition into fall. For more detailed information, check out Saint John weather in October.
May and November present contrasting weather patterns in terms of temperature and precipitation. In May, temperatures range from a minimum of 1°C (33°F) to a maximum of 20°C (68°F), with an average of 9°C (48°F). The month experiences 117 mm (4.6 in) of precipitation over approximately 12 days, creating a relatively mild and humid atmosphere with humidity levels around 78%. In contrast, November brings cooler conditions, with temperatures dipping as low as -12°C (10°F) and peaking at 16°C (62°F), averaging 5°C (40°F). This month also sees increased precipitation, totaling 184 mm (7.3 in) over about 14 days, coupled with higher humidity at 84%. For more detailed information, you can explore Saint John weather in November.
May and December present stark contrasts in weather patterns. In May, temperatures range from a chilly 1°C (33°F) at night to a pleasant maximum of 20°C (68°F) during the day, accompanied by an average of 9°C (48°F). The month is relatively wet, with 117 mm (4.6 in) of precipitation spread over 12 days and a humidity level of 78%.
Conversely, December's temperatures dip significantly, reaching a minimum of -18°C (-1°F) and topping out at 14°C (57°F), with an average of -1°C (31°F). This month also experiences higher precipitation at 142 mm (5.6 in) over the same number of days, with humidity slightly elevated at 82%. For more details on December weather, refer to Saint John weather in December.
As spring unfolds in May, Saint John's weather transitions to a more pleasant and inviting atmosphere, marking a significant shift from the colder months. With rising temperatures averaging around 9°C, this month invites locals and visitors alike to embrace the outdoors, though the crisp morning air lingers with cooler minimums. While May brings some rainfall, with 12 days of precipitation, it also contributes to the lush greenery that characterizes the landscape as spring blossoms into life. This unique blend of mild temperatures and moderate humidity at 78% makes May a delightful time to explore the vibrant beauty of the city. For more insights into the weather patterns and what to expect throughout the year, visit Saint John Climate.