Last updated: February 24, 2025
In May, Philadelphia experiences a diverse range of weather conditions, with temperatures fluctuating between a maximum of 35°C (95°F) and a minimum of 2°C (35°F). The average temperature settles at a mild 18°C (65°F), making it a comfortable time for outdoor activities. However, it's important to prepare for the wet days, as precipitation totals reach 133 mm (5.2 in) over approximately 14 days, contributing to a relatively high humidity level of 78%. This combination of warmth and moisture shapes a vibrant but variable climate, indicative of spring's transition towards summer.
In May, temperatures in Philadelphia begin to shed the chill of winter, ushering in a vibrant spring atmosphere. With a minimum temperature of 2°C (35°F) and an average rising to 18°C (65°F), the city begins to warm significantly. Days can reach a maximum of 35°C (95°F), highlighting the month’s potential for unexpected heatwaves. This transitional period not only showcases an increase in warmth compared to April's cooler average of 12°C (55°F) but also reflects a clear trend towards summer readiness, as the city gears up for the hotter months ahead. The climbing temperatures invite residents to enjoy outdoor activities and cultural events, making May a lively and vibrant time in Philadelphia.
May in Philadelphia typically marks a significant uptick in precipitation, as the city averages 133 mm (5.2 in) of rainfall over the month, making it one of the wettest periods of the year. This increase is reflected in the number of precipitation days, with rain falling on approximately 14 days, setting a trend for the summer months ahead. The consistent moisture helps to nourish the burgeoning greenery, creating a lush landscape, while the frequent showers can sometimes catch residents off guard. As the city transitions into the warmer season, these rainy days contribute to a vibrant, thriving environment, showcasing the delicate balance between sun and rain that defines Philadelphia's springtime charm.
As spring transitions into summer, May brings a noticeable decline in humidity levels in Philadelphia, dropping to 78%. This shift reflects a gradual decrease from the higher humidity percentages seen in the winter and early spring months, where averages hover around 84% to 81%. The trend indicates that as temperatures rise in the coming months, humidity will continue to fluctuate, reaching its lowest in the height of summer before beginning to climb again in late fall. Such changes create a dynamic climate that residents experience, with May marking a refreshing pause before the summer heat sets in.
In May, Philadelphia experiences a significant rise in UV exposure, with the UV Index reaching 10—indicating a very high risk of harm from unprotected sun exposure. As the weather warms, residents should be particularly cautious, as the burn time is a mere 15 minutes. This trend follows an upward trajectory from earlier months, where January’s moderate index of 3 slowly climbs to February's 5 and March's 6. April serves as a precursor to May’s peak with its own 9 index, urging Philadelphians to prepare for sun protection. As summer approaches, awareness is crucial; for more details on managing UV exposure throughout the year, check out the comprehensive guide on Philadelphia UV Index.
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As spring blossoms into summer, May in Philadelphia shines brightly with 273 hours of sunshine, showcasing a remarkable increase from the preceding months. Following a steady rise from January’s modest 144 hours, the city embraces longer days and warmer temperatures, with sunlight steadily climbing through April. This trend continues into June, where sunshine peaks at 311 hours, ushering in the peak of summer. The gradual ascent in sunlight hours reflects the vibrant energy of the city as residents eagerly enjoy outdoor activities and events, making May a delightful precursor to the sun-soaked days ahead.
As May rolls around in Philadelphia, residents can expect a 40% chance of sunny weather, slightly below the spring average. This statistic sits between the more promising forecasts of March at 55% and April at 44%, hinting at a transitional period where sunshine is still a delightful, albeit less certain, visitor. Interestingly, as we look toward the summer months, the likelihood of sunshine appears to decline further, with June dipping to 36% and August falling to 33%. This trend suggests that while May retains a fair amount of sunny potential, those craving consistent sunny days may find them more prevalent in the early spring and late summer, rather than in the heart of late spring.
As spring transitions into summer, May shines brightly with 14 hours of daylight in Philadelphia, marking a significant increase from the 13 hours experienced in April. This trend of lengthening days highlights the approach of peak summer, where daylight reaches its zenith around June, sustaining at 14 hours for a few months before beginning its gradual decline. The increasing daylight duration not only enhances outdoor activities but also uplifts spirits, as residents and visitors alike bask in the longer, sunlit hours that May graciously delivers.
In Philadelphia, the winds of May bring a gentle breeze with an average speed of 3.1 m/s (7 mph), marking a slight decline from the more spirited March and April winds. This decrease signals the transition into summer, as the city prepares for the calmer gusts of June, which drop to 2.7 m/s (6 mph). Notably, May maintains a steady airflow compared to the brisker early spring months, offering a refreshing touch to the pleasant temperatures. As the seasons change, the wind gradually softens, making way for those lazy summer days ahead, while also hinting at the cyclical nature of Philadelphia's climate, where the coming months will continue to see wind speeds taper off further.
The weather in Philadelphia 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 Philadelphia and find detailed weather information for every month.
May and January present stark contrasts in weather. In May, temperatures range from a cool minimum of 2°C (35°F) to a warm maximum of 35°C (95°F), averaging around 18°C (65°F). This month experiences considerable precipitation, with about 133 mm (5.2 in) falling over an average of 14 days, and a humidity level of 78%. In contrast, January is much colder, with temperatures hovering between a minimum of -17°C (1°F) and a maximum of 20°C (68°F), averaging only 2°C (36°F). Despite having less precipitation at 63 mm (2.5 in) over 9 days, January has a higher humidity level of 84%. For more details, check out Philadelphia weather in January.
May and February present starkly contrasting weather patterns. In May, temperatures range from a chilly 2°C (35°F) at night to a warm 35°C (95°F) during the day, with an average of 18°C (65°F). The month experiences 133 mm of rainfall over 14 days, coupled with a humidity level of 78%. In contrast, February features much colder temperatures, dropping to a minimum of -15°C (5°F) and peaking at 26°C (78°F), with an average of only 4°C (39°F). It also sees slightly less precipitation at 108 mm over 11 days, although the humidity remains high at 83%. For more detailed insights on February weather, you can visit Philadelphia weather in February.
In comparing the weather between May and March, it's clear that May brings significantly warmer temperatures, with an average of 18°C (65°F) compared to March's cooler average of 7°C (44°F). March experiences lower minimum temperatures, plunging to -11°C (12°F), while May's minimum rarely drops below 2°C (35°F). Rainfall is more frequent in May, with precipitation occurring on about 14 days, resulting in 133 mm (5.2 in) of rain, compared to March's 107 mm (4.2 in) over 10 days. Although May has slightly lower humidity at 78%, it's still quite humid compared to the 83% during March. For more detailed insights, you can explore Philadelphia weather in March.
May generally features warmer temperatures compared to April, with average highs reaching 18°C (65°F) and max temperatures soaring up to 35°C (95°F), compared to April's average high of 12°C (55°F) and maximum of 32°C (89°F). While both months experience notable rainfall, May records 133 mm (5.2 in) across 14 days, slightly more than April's 105 mm (4.1 in) over 11 days. Interestingly, humidity levels in May average around 78%, just a bit lower than April's 81%. For a detailed look at the weather patterns in April, you can check Philadelphia weather in April.
May and June in the region exhibit a notable shift in weather patterns. In May, temperatures range from a brisk minimum of 2°C (35°F) to a warm maximum of 35°C (95°F), with an average of 18°C (65°F). This month also experiences significant rainfall, totaling 133 mm (5.2 in) over 14 days, contributing to humidity levels of 78%. In contrast, June sees a warmer climate with minimum temperatures rising to 10°C (50°F) and maximums reaching 36°C (98°F), resulting in an average temperature of 23°C (74°F). While June has slightly less precipitation at 102 mm (4.0 in) over 11 days, humidity remains high at 79%. Overall, June offers a generally warmer and drier experience compared to May. For more details, check out Philadelphia weather in June.
In May, temperatures range from a cool minimum of 2°C (35°F) to a warm maximum of 35°C (95°F), with an average temperature of 18°C (65°F). The month experiences significant precipitation, totaling 133 mm (5.2 in) over about 14 days, alongside high humidity levels of 78%. In contrast, July sees warmer conditions, with temperatures ranging from a minimum of 14°C (58°F) to a peak of 37°C (99°F) and an average of 26°C (79°F). Precipitation remains relatively similar at 131 mm (5.2 in) but occurs over just 13 days, and humidity slightly decreases to 74%. For more information, check Philadelphia weather in July.
In May, temperatures in the area range significantly, with a minimum of 2°C (35°F) and an average of 18°C (65°F), while it can peak at a warm 35°C (95°F). This month also sees a notable amount of precipitation at 133 mm (5.2 in) over 14 days, accompanied by relatively high humidity levels at 78%. In contrast, August offers milder mornings with a minimum temperature of 14°C (58°F) and a comfortable average of 25°C (77°F), while still reaching a maximum of 35°C (96°F). Rainfall in August is slightly higher at 134 mm (5.3 in) and also occurs over 14 days, but the humidity decreases to 72%, making the heat feel more bearable. For a closer look at what to expect, check out Philadelphia weather in August.
In May, temperatures range from a minimum of 2°C (35°F) to a maximum of 35°C (95°F), averaging around 18°C (65°F). The month experiences significant precipitation, totaling 133 mm (5.2 in) over about 14 days, accompanied by high humidity at 78%. In contrast, September sees a slightly warmer average temperature of 22°C (71°F) with a minimum of 6°C (44°F) and a maximum that matches May at 35°C (95°F). The precipitation is less, totaling 93 mm (3.7 in) over just 10 days, and humidity levels are marginally lower at 75%. For more specifics on the weather conditions, you can refer to Philadelphia weather in September.
May and October in Philadelphia present notable weather contrasts despite sharing similar temperature extremes. In May, temperatures range from a minimum of 2°C (35°F) to a maximum of 35°C (95°F), with an average of 18°C (65°F) and relatively high precipitation of 133 mm (5.2 in) across 14 days. October, on the other hand, sees slightly cooler temperatures with a minimum of 2°C (37°F) and a maximum of 35°C (96°F), averaging around 16°C (61°F). The month is less rainy, boasting only 106 mm (4.2 in) over 9 days, but has a marginally higher humidity level at 81%. For a more detailed outlook on Philadelphia weather in October, you can explore the specifics further.
May and November exhibit stark contrasts in weather. In May, temperatures range from a minimum of 2°C (35°F) to a high of 35°C (95°F), with an average of 18°C (65°F). The month is characterized by substantial rainfall, amounting to 133 mm (5.2 in) over 14 days, accompanied by a humidity level of 78%. In contrast, November experiences much cooler conditions, with temperatures dipping as low as -8°C (18°F) and peaking at 25°C (77°F), averaging around 8°C (47°F). Rainfall is lower in November, with about 83 mm (3.3 in) over 8 days, and slightly higher humidity at 85%. For a detailed look at November weather, visit Philadelphia weather in November.
May and December present striking contrasts in weather patterns. In May, temperatures range from a mild 2°C (35°F) at night to a warm 35°C (95°F) during the day, with an average of 18°C (65°F). The month sees around 133 mm (5.2 in) of precipitation over 14 days and maintains a humidity level of 78%. In contrast, December experiences much colder temperatures, with a minimum of -12°C (10°F) and a maximum of 19°C (67°F), averaging just 4°C (40°F). Although the total precipitation is slightly lower at 100 mm (4.0 in) over 10 days, the humidity is slightly higher at 84%. These differences highlight the seasonal transition between the warmth of spring and the chill of winter. For more detailed information, you can visit Philadelphia weather in December.
As the vibrant bloom of spring unfolds, May in Philadelphia brings a delightful shift in weather that contrasts sharply with the preceding months. With warmer temperatures settling in, residents can expect more sun-kissed days and the occasional heat wave, making it the perfect time for outdoor activities. However, along with the rising warmth, May also ushers in a higher chance of rain, with nearly half the month experiencing precipitation. This blend of warmth and humidity creates a refreshing yet sometimes unpredictable climate, setting the stage for the vibrant summer ahead. To explore more about the fascinating weather patterns throughout the year, visit Philadelphia Climate.