Last updated: August 21, 2025
In May, both the USA and Japan experience a vibrant transition into spring, with temperatures reaching a maximum of 30°C (86°F) and an average of 20°C (68°F), offering warm days for outdoor activities. However, the evenings can cool down to a minimum of 9°C (48°F), so light jackets might be handy. The weather is often playful, featuring 156 mm (6.2 in) of precipitation over approximately 11 days, which can lead to lush, green landscapes. With an average humidity of 84%, expect a blend of pleasantly warm days and the occasional rain shower, perfect for enjoying the unique charm of this season.
In May, the temperatures in the U.S. and Japan begin to blossom into the warmth of spring, showcasing a delightful transition. With minimums rising to 9°C (48°F) and an average of 20°C (68°F), the days become pleasantly balmy, peaking at a cozy 30°C (86°F). This is a significant leap from earlier months, hinting at the summer heat ahead. As flowers bloom and outdoor activities beckon, both countries experience a surge in warmth, melding comfortable days with cooler evenings. The upward trend from April underscores the shift toward summer, making May a vibrant month filled with life and warmth in both regions.
In May, the precipitation in the USA reaches a notable peak at 156 mm (6.2 inches), reflecting the transition into a wetter season. This increase is consistent with the overall upward trend observed in spring months, where rainfall builds after the relatively dry winter. Notably, May sees 11 days of precipitation, providing a refreshing contrast to the drier months that precede it. In comparison, Japan also experiences significant rainfall during this month, as it braces for the approaching rainy season, marked by lush landscapes and increased moisture. Both countries show a clear pattern of rising precipitation leading into the summer, setting the stage for the more intense rains of June and July.
As the seasons shift in both the USA and Japan, May marks a notable rise in humidity, peaking at 84%. This increase follows a moderately humid spring, with April at 78%, suggesting a trend towards more saturated air as summer approaches. The transition is quite significant compared to the earlier months, where humidity levels hover in the low seventies. By May, the air becomes palpably heavier, paving the way for the sultry conditions of June that continue to climb to 86%. This upward trajectory in humidity not only signals the onset of warmer months but also highlights a stark contrast to the drier, cooler winter months, as the lush landscapes of both countries prepare for the vibrant energy of summer.
As we move into May in both the USA and Japan, the UV Index stands at an intense 11, categorized as extreme. This marks a continuation of elevated UV levels experienced since April, where the burn time shrinks down to a swift 10 minutes for unprotected skin. Observing the progression from January's moderate exposure of 4 to the alarming numbers in recent months highlights a consistent rise in UV radiation, prompting increased vigilance for sun safety. As summer approaches, the UV Index remains a critical factor in outdoor planning and personal protection. For detailed information on UV levels, visit Usa UV Index.
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As spring transitions into summer, May shines brightly in both the USA and Japan, boasting an impressive 292 hours of sunshine. This month marks a notable increase from April's 276 hours, showcasing a steady upward trend in daylight as we approach the sunniest months of the year. The consistent rise in sunshine hours from January's 172 hours to May's peak reflects the joyful awakening of nature and the vibrant energy of longer days. Following May, the sunlight begins to slightly taper off into June and July, indicating a natural ebb, but the enthusiasm for the beautiful weather continues to flourish. With August reaching an exhilarating 297 hours, it’s clear that these months are cherished by many, highlighting the warmth and vitality that sunshine brings to life in both nations.
As spring transitions into summer, the likelihood of sunny weather in both the USA and Japan tends to fluctuate, with May experiencing a notably low chance of sunshine at just 32%. This marks a drop from the previous months, especially compared to April's sunnier disposition at 44%. The trend reveals that while early spring may offer occasional bright days, the onset of May introduces a more unpredictable weather pattern, often accompanied by increased cloud cover and precipitation. Interestingly, as the year progresses towards autumn, the chance of sunny days picks up again, peaking in October at an impressive 62%, hinting that while May's weather may be less favorable, the sun returns with vigor just a few months later.
As the year progresses in the USA and Japan, daylight duration undergoes notable changes, reflecting the shift in seasons. Starting with a stable 10 hours of daylight during January and February, there’s a gradual increase as spring approaches, peaking at 13 hours in both April and May. This trend continues into the summer months of June and July, where daylight reaches its annual high at 14 hours, providing ample sunlight for outdoor activities. However, as summer fades into autumn, daylight begins to taper off, dropping to 12 hours in September and continuing its descent through the fall, ultimately returning to 10 hours by November. This cyclical pattern highlights the rhythmic dance of daylight and darkness throughout the year, inviting exploration of nature and seasonal festivities.
In May, the average wind speed in the USA and Japan drops to 2.8 m/s (6 mph), reflecting a slight decrease from the earlier months like January and February, which boasted stronger winds of 3.0 m/s and 3.6 m/s respectively. This trend continues downward into June, where the wind speed further declines to 2.2 m/s (5 mph). April's winds, returning briefly to 3.0 m/s, act as a transitional phase before entering the more tranquil breezes of late spring and summer. Interestingly, this seasonal pattern hints at a cyclical nature where wind speeds fluctuate, peaking in the winter months before settling into a calmer state during the warmer period, only to rise again as autumn approaches. Overall, May serves as a pivotal point, marking the transition into milder wind conditions.
Weather in Usa varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in Usa, focusing on differences in temperature, rainfall, humidity, and UV levels.
May presents a warm and vibrant contrast to the chilly depths of January. With temperatures ranging from a minimum of 9°C (48°F) to a maximum of 30°C (86°F), May averages a comfortable 20°C (68°F), while enjoying significantly higher humidity at 84%. In comparison, January's frigid temperatures drop to a minimum of -4°C (25°F) and peak at a mild 16°C (61°F), averaging just 6°C (42°F). Additionally, January experiences less rainfall at 52 mm (2.0 in) over 6 days, compared to May's 156 mm (6.2 in) across 11 days. For more detailed insights, you can check Usa weather in January.
May's weather is considerably warmer and more humid compared to February. With average temperatures ranging from a cool 20°C (68°F) to a peak of 30°C (86°F), May truly ushers in the vibrancy of spring, despite receiving 156 mm (6.2 in) of rainfall over about 11 days. In contrast, February experiences much chillier conditions, with average temperatures hovering around 6°C (44°F) and a maximum of only 20°C (68°F), while precipitation is also lighter, totaling 71 mm (2.8 in) over 10 days. Overall, May offers a much more tropical feel, while February is characterized by crisp, wintery air. For more detailed information about February weather, check out Usa weather in February.
May typically showcases warmer weather compared to March, with average temperatures rising from 11°C (51°F) in March to a pleasant 20°C (68°F) in May. The maximum temperature in May can reach up to 30°C (86°F), while March peaks at 21°C (71°F). Additionally, May experiences higher humidity levels at 84%, significantly elevated from the 71% seen in March. Although May has slightly more precipitation, totaling 156 mm (6.2 in) over 11 days, March records 122 mm (4.8 in) of rainfall across 12 days. For more insights into March weather conditions, visit Usa weather in March.
In comparing the weather of April and May, we see a notable increase in temperatures and humidity levels. April experiences a minimum temperature of 5°C (41°F) and an average of 15°C (59°F), while May sees a rise to a minimum of 9°C (48°F) and an average of 20°C (68°F). The maximum temperatures also shift, with April peaking at 25°C (78°F) compared to May's 30°C (86°F). Furthermore, May has higher precipitation, totaling 156 mm (6.2 in) over 11 days, compared to April's 114 mm (4.5 in) across 9 days. With humidity levels also increasing from 78% in April to 84% in May, it's evident that May brings warmer and wetter conditions overall. For more detailed weather information, check out Usa weather in April.
In comparing the weather of May and June, we notice a significant rise in temperature, with June averaging at 23°C (74°F) compared to May's 20°C (68°F). The minimum temperatures increase notably from 9°C (48°F) in May to 16°C (61°F) in June, offering a warmer start to summer. However, June also sees a slight increase in precipitation, totaling 194 mm (7.6 in) over 14 days, compared to May's 156 mm (6.2 in) over 11 days, indicating a wetter month overall. Humidity remains similar, with June at 86% and May at 84%, contributing to that muggy summer feel. For more detailed information, you can check Usa weather in June.
In May, temperatures begin to warm up, with a minimum of 9°C (48°F) and an average of 20°C (68°F), peaking at a maximum of 30°C (86°F). The month experiences significant rainfall, totaling 156 mm (6.2 in) over approximately 11 days, and humidity levels are relatively high at 84%.
In contrast, July brings hotter weather, with minimum temperatures rising to 19°C (67°F) and an average of 27°C (80°F), reaching a maximum of 34°C (93°F). However, this increase in temperature comes with even more precipitation, totaling 329 mm (13.0 in) over about 19 days, and humidity levels rising to 92%. For more details on July weather, you can visit Usa weather in July.
In May, the weather is relatively mild, with temperatures ranging from a minimum of 9°C (48°F) to a maximum of 30°C (86°F) and an average temperature of 20°C (68°F). However, it experiences quite a bit of rain, with a total precipitation of 156 mm (6.2 in) falling over 11 days, alongside a humidity level of 84%. In contrast, August brings significantly warmer temperatures, with a minimum of 20°C (68°F), an average of 28°C (83°F), and a high of 35°C (95°F). This month also sees increased rainfall, totaling 224 mm (8.8 in) over 14 days, and slightly higher humidity at 91%. For more details on weather patterns in August, you can visit Usa weather in August.
In May, the weather tends to be mild with average temperatures around 20°C (68°F) and a maximum of 30°C (86°F), but the month is marked by higher precipitation, totaling 156 mm (6.2 in) over approximately 11 rainy days. In contrast, September experiences warmer temperatures, with averages reaching 24°C (76°F) and highs of 33°C (91°F), though it also sees slightly more rainfall at 173 mm (6.8 in) over about 15 days. Both months share a consistent humidity level of 84%, creating a humid environment throughout. For a closer look at seasonal trends, you can check out this link: Usa weather in September.
May and October present a transition in weather patterns, with both months offering mild temperatures and relatively high humidity. In May, the minimum temperature hovers around 9°C (48°F), peaking at 30°C (86°F) on warmer days, while October shows a slightly higher minimum of 10°C (50°F) and a maximum of 29°C (85°F). Precipitation levels are comparable, with May receiving 156 mm (6.2 in) over 11 days, while October totals 138 mm (5.4 in) over just 9 days, indicating a slightly drier spell as the year winds down. Humidity remains high in both months, at 84% in May and falling just a notch to 83% in October. For more insights on weather patterns, check out Usa weather in October.
May and November showcase a distinct contrast in weather patterns. In May, temperatures fluctuate from a minimum of 9°C (48°F) to a warm average of 20°C (68°F) and can reach a maximum of 30°C (86°F). This month experiences 156 mm (6.2 in) of precipitation over about 11 days, contributing to a high humidity level of 84%. Conversely, November brings cooler temperatures, with a minimum of 4°C (40°F), an average of 13°C (56°F), and a maximum of 26°C (79°F). The precipitation is significantly lower in November, totaling 47 mm (1.9 in) over just 6 days, and the humidity decreases slightly to 81%. This makes May generally warmer and wetter than November, highlighting the seasonal transition as the year progresses. For more details on November weather, visit Usa weather in November.
May and December offer notably different weather experiences. In May, temperatures range from a mild 9°C (48°F) at night to a warm 30°C (86°F) during the day, with an average of 20°C (68°F). This month sees significant rainfall, with about 156 mm (6.2 in) spread over 11 days, contributing to a high humidity level of 84%. In contrast, December presents a much cooler climate, with temperatures dropping to a minimum of -1°C (31°F) and peaking at 21°C (71°F), averaging 8°C (46°F). Precipitation decreases sharply to 59 mm (2.3 in) over 8 days, with humidity slightly lower at 79%. For more details on weather in December, check this link: Usa weather in December.
As May unfolds in the USA, the weather showcases a delightful transition into warmer days, marked by a blend of comfortable temperatures and increased humidity. Unlike the chill of earlier spring months, May brings a pleasant balance with its average warmth, creating an inviting atmosphere for outdoor activities. However, as the month progresses, occasional rain can be expected, with precipitation occurring on several days, reminding residents of nature's whims. This contrasting combination of warmth and humidity makes May a unique bridge between the cooler spring and the upcoming heat of summer. To explore more about the climate in this vibrant season, visit Usa Climate.