Last updated: August 21, 2025
In May, the charming city of Karatsu, Japan experiences a delightful transition into warmer weather. With a maximum temperature reaching around 27°C (80°F) and an average of 19°C (67°F), it’s the perfect time to enjoy the outdoors. However, visitors should be prepared for some rain, as the month sees about 153 mm (6.0 in) of precipitation over 11 days, creating a lush environment. The humidity levels hover at a high 87%, adding a touch of tropical warmth to the vibrant spring atmosphere. This combination of warmth and occasional showers makes May an ideal time to explore Karatsu’s beautiful landscapes and cultural treasures.
In May, Karatsu, Japan begins to shake off the lingering chill of spring, ushering in more comfortable temperatures that invite outdoor exploration. With a minimum of 11°C (53°F) and a delightful average of 19°C (67°F), the days warm up nicely, reaching a pleasant maximum of 27°C (80°F). This significant jump in temperature from the cooler months marks a blossoming transition, as nature comes alive in vibrant colors and scents. As the month progresses, the mild and inviting climate makes May an ideal time for locals and visitors alike to enjoy the beauty of Karatsu's gardens and coastal views.
In May, Karatsu, Japan experiences a notable uptick in precipitation, receiving 153 mm (6.0 in) of rain over 11 days. This marks a significant increase from April's 115 mm (4.5 in), highlighting the city's transition into the wetter part of the year. As spring progresses, the rainfall sets the stage for lush landscapes, making May one of the months that contribute to the vibrant greenery seen later in the summer. Interestingly, the rainfall continues to build into the following months, with June rising sharply to 191 mm (7.5 in), indicating a trend of increasing precipitation as the region approaches its peak rainy season.
In May, Karatsu, Japan, experiences a notable spike in humidity, reaching 87%, which marks a significant rise compared to the preceding months. This increase sets the stage for the onset of summer, as April's humidity of 79% transitions into June's even higher level of 91%. The month of May is characterized by a lush, vibrant atmosphere, with moisture levels steadily climbing. As the region moves into the heart of summer, humidity peaks in July at a staggering 97%, illustrating a clear trend of escalating humidity that continues through the summer months, before tapering off into the drier fall. This pattern emphasizes the tropical climate of Karatsu, where the air feels thick and rich with moisture, especially in late spring and early summer.
As May arrives in Karatsu, Japan, residents and visitors alike should be prepared for a significant increase in the UV Index, which soars to 11, categorizing it as extreme and reducing burn time to just 10 minutes. This sharp rise follows a trend of escalating UV levels as spring transitions into summer, with April also marking a very high index of 10. The intensity in May is indicative of the region's growing exposure to solar radiation, persisting through June and July, when the index peaks further at 12. It's essential for everyone to take precautions during this time, prioritizing sun safety to avoid harmful effects. For more detailed insights, explore Karatsu UV Index.
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In May, Karatsu, Japan, basks in the glow of 293 hours of sunshine, marking a peak in the vibrant spring season. This delightful month continues the upward trend in sunlight that begins in January with only 178 hours. As the year progresses, the hours of sunshine steadily increase, with March and April showing significant growth at 262 and 281 hours, respectively. May shines particularly bright, outpacing all preceding months and hinting at the sun-drenched days of summer ahead. Following May, June sees a slight dip to 282 hours, yet it remains a sunlit haven, illustrating the gradual transition towards the sunnier and longer days of July and August, where sunshine hits a peak of 305 hours. This trend not only highlights the changing seasons but also invites visitors to revel in the rich and warm ambience that Karatsu offers during this lively month.
May in Karatsu, Japan, presents a 33% chance of sunny weather, positioning it slightly below earlier months like April. This suggests a gradual decrease in sunny days as spring gives way to the early onset of summer. While April still holds a higher likelihood of sunshine, May's sunshine reliability aligns with the trend observed from previous months, where the probability of clear skies tends to decline ahead of the summer’s typically more overcast conditions. As the year progresses into June, the chance of sunshine dips further, reaching a low of 27%, indicating that those seeking bright days might do well to enjoy the fleeting sunlight of May while it lasts. Overall, the pattern reveals a seasonal shift, making May’s sunshine a precious commodity before the summer humidity sets in.
As spring unfolds in Karatsu, Japan, daylight duration gradually increases, marking a significant shift in the seasons. In April, the days stretch to a comfortable 13 hours, a delightful prelude to May, where daylight remains steady at 13 hours. This consistency hints at the onset of summer, which in June and July sees daylight peak at a vibrant 14 hours. Following this luminous high, daylight begins to gently recede, easing back to 13 hours in August before transitioning into the softer light of autumn. As the year progresses, daylight gradually diminishes to 10 hours by November and further to a crisp 9 hours in December, bringing the cycle full circle. This rhythm of light not only guides the daily lives of Karatsu's residents but also beautifully represents the changing seasons.
In Karatsu, Japan, the breeze begins to soften in May, with an average wind speed of 3.7 m/s (8 mph), marking a noticeable decline from the earlier months. This gentle wind, ideal for outdoor activities, reflects the transition into summer, where the winds typically remain calmer, peaking in July and August at around 3.3 m/s (7 mph). Comparing the spring months, May holds a unique charm where the air feels lighter, allowing for pleasant strolls along the coast as the landscape bursts into bloom. As the year progresses, the winds pick up slightly in the fall, hinting at seasonal changes, but May distinctly represents a breezy lull, inviting both locals and visitors to embrace the mild, refreshing atmosphere.
Weather in Karatsu varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in Karatsu, focusing on differences in temperature, rainfall, humidity, and UV levels.
May and January present strikingly contrasting weather conditions. In May, temperatures range from a mild 11°C (53°F) at night to a warm 27°C (80°F) during the day, with an average of 19°C (67°F). This month also sees 153 mm (6.0 in) of precipitation over 11 days and a high humidity level of 87%. In contrast, January experiences much cooler weather, with temperatures dipping to a minimum of -1°C (31°F) and peaking at 18°C (64°F), averaging 8°C (46°F). Rainfall is less frequent, totaling 69 mm (2.7 in) over 9 days, accompanied by a lower humidity at 73%. For more detailed information on January weather, you can visit Karatsu weather in January.
May generally offers much warmer temperatures compared to February, with average readings soaring from a low of 11°C (53°F) to a high of 27°C (80°F), while February’s temperatures range from a chilly 0°C (31°F) to a milder 19°C (67°F). The increased warmth in May also comes with higher humidity levels at 87%, compared to February's more comfortable 69%. Precipitation is more significant in May, accumulating 153 mm (6.0 in) over 11 rainy days, whereas February sees only 84 mm (3.3 in) during the same number of days. For more details on February weather, you can visit Karatsu weather in February.
When comparing the weather in March and May, it’s clear that May offers a warmer and more humid climate. In May, temperatures range from a minimum of 11°C (53°F) to a maximum of 27°C (80°F), with an average of 19°C (67°F). In contrast, March is cooler, with temperatures ranging from a minimum of 5°C (41°F) to a maximum of 20°C (68°F), and an average of just 12°C (53°F). Both months experience around 11 days of precipitation, but May sees slightly more rainfall at 153 mm (6.0 in) compared to March's 136 mm (5.4 in). Additionally, the humidity levels in May are higher at 87%, compared to March's 71%. This variation highlights the transition from the chill of early spring to the warmth of late spring, making each month distinctly different. For more details on March weather, check out Karatsu weather in March.
In comparing the weather between April and May, it is evident that May experiences warmer temperatures overall. While April sees a minimum temperature of 7°C (45°F) and an average of 15°C (59°F), May's temperatures rise, with a minimum of 11°C (53°F) and an average of 19°C (67°F). Additionally, May tends to be wetter, reporting 153 mm (6.0 in) of precipitation over 11 days compared to April's 115 mm (4.5 in) over just 9 days. The humidity also increases in May, reaching 87%, compared to April's 79%. For more details about April's weather, you can visit Karatsu weather in April.
In May, temperatures in Karatsu typically range from a minimum of 11°C (53°F) to a maximum of 27°C (80°F), with an average of 19°C (67°F). The month experiences significant rainfall, totaling 153 mm (6.0 in) over about 11 days, accompanied by high humidity levels of 87%. In contrast, June sees warmer conditions, with minimum temperatures rising to 17°C (63°F) and maximums reaching 29°C (84°F), resulting in an average of 22°C (73°F). However, June also brings increased precipitation, averaging 191 mm (7.5 in) over 13 days, and humidity levels slightly higher at 91%. For more detailed information about the weather in June, check out Karatsu weather in June.
May and July exhibit notable differences in weather patterns. In May, temperatures range from a minimum of 11°C (53°F) to a maximum of 27°C (80°F), with an average of 19°C (67°F) and a relatively high humidity level of 87%. This month also experiences 153 mm (6.0 in) of precipitation across 11 days.
In contrast, July sees significantly warmer temperatures, with minimums around 20°C (68°F), averages of 26°C (79°F), and maximums reaching 33°C (91°F). The humidity spikes to a striking 97%, and the month is much wetter, receiving 323 mm (12.7 in) of rainfall over 18 days. For a more detailed look at July's weather, you can visit Karatsu weather in July.
In May, temperatures begin to warm up with a minimum of 11°C (53°F) and an average of 19°C (67°F), reaching up to a pleasant maximum of 27°C (80°F). However, this month is also marked by significant rainfall, receiving about 153 mm (6.0 in) over 11 days, accompanied by relatively high humidity at 87%.
In contrast, August experiences much warmer weather, with minimum temperatures around 21°C (70°F) and average highs reaching 28°C (83°F), peaking at a maximum of 33°C (92°F). The month is wetter, with total precipitation of 266 mm (10.5 in) over 13 days, and humidity rises to 94%. For more details on the August climate specifics, you can check out Karatsu weather in August.
Overall, while May offers a mild and moderately rainy spring, August boasts hotter temperatures and increased humidity, making it a more tropical experience.
In comparing the weather between May and September, we notice a significant increase in temperature as the seasons transition. May features a milder climate, with average temperatures ranging from a cool 11°C (53°F) to a warm 27°C (80°F), while September experiences warmer conditions, with temperatures ranging from 19°C (66°F) to a peak of 32°C (91°F). However, September also sees a rise in precipitation, averaging 210 mm (8.3 in) over 16 days, compared to May's 153 mm (6.0 in) over 11 days. Despite the slightly lower humidity in September at 84%, the overall warmth and increased rainfall contribute to a more tropical feel. For a detailed look at conditions specific to one location, check out Karatsu weather in September.
May and October both exhibit pleasant temperatures, with May averaging 19°C (67°F) and October slightly warmer at an average of 20°C (69°F). The maximum temperatures in October can reach up to 29°C (84°F), making it a bit warmer than May, where the max is 27°C (80°F). However, May tends to be wetter, with 153 mm (6.0 in) of precipitation over 11 days compared to October's 112 mm (4.4 in) over 10 days. Additionally, humidity levels are higher in May at 87%, while October experiences a more comfortable humidity of 79%. For more detailed insights, you can check Karatsu weather in October.
May and November present contrasting weather patterns. In May, temperatures range from a minimum of 11°C (53°F) to a maximum of 27°C (80°F), with an average temperature of 19°C (67°F). This month experiences significant rainfall with about 153 mm (6.0 in) over 11 days, and high humidity levels at 87%. In contrast, November sees cooler temperatures, with a minimum of 7°C (45°F), an average of 15°C (59°F), and a maximum of 23°C (74°F). Precipitation drops to 53 mm (2.1 in) over just 7 days, and humidity decreases to 75%. For more details about November weather, you can visit Karatsu weather in November.
In May, the weather is significantly warmer, with average temperatures ranging from a minimum of 11°C (53°F) to a maximum of 27°C (80°F), highlighting the arrival of spring. However, this month also experiences higher precipitation, totaling 153 mm (6.0 in) over approximately 11 rainy days, along with a high humidity level of 87%. In contrast, December offers a much cooler climate, where temperatures typically range from a minimum of 1°C (35°F) to a mild maximum of 21°C (71°F), with an average of 10°C (50°F). The month sees considerably less rainfall at 81 mm (3.2 in) over 9 days, and lower humidity at 72%. For more details on December weather in this region, you can visit Karatsu weather in December.
As spring transitions into summer, May in Karatsu offers a delightful blend of mild warmth and vibrant greenery. With an average temperature of 19°C, it stands out as a pleasing month compared to the cooler temperatures of earlier spring months. However, the increased humidity—averaging around 87%—and heightened precipitation levels with about 11 rainy days can bring a refreshing, albeit damp, atmosphere. This unique weather pattern makes May a time of rejuvenation, as nature flourishes and prepares for the hotter months ahead. For more insights into the city's climate year-round, visit Karatsu Climate.