Last updated: August 21, 2025
April in Karatsu, Japan is characterized by a delightful mix of mild temperatures and significant humidity. With maximum temperatures reaching up to 24°C (75°F) and an average of 15°C (59°F), the weather is perfect for outdoor exploration. However, the month experiences about 115 mm (4.5 inches) of rain spread over 9 days, contributing to a humidity level of 79% that blankets the region. This combination of warmth and moisture creates a vibrant atmosphere, making April a picturesque time to visit Karatsu.
In April, Karatsu experiences a delightful transition into spring, marked by a noticeable rise in temperatures. The minimum temperature settles around 7°C (45°F), while the average climbs to a comfortable 15°C (59°F), peaking at a pleasant 24°C (75°F). This increase reflects a broader trend as the region shifts from the chill of winter, with March averaging just 12°C (53°F), to the warmer embrace of May, where temperatures soar to an average of 19°C (67°F). April's mild conditions provide an ideal backdrop for outdoor activities and the blossoming of cherry blossoms, making it a vibrant month in the picturesque setting of Karatsu. As the days grow longer and warmer, the natural beauty of the area comes alive, inviting both locals and visitors to revel in the increasingly inviting weather.
In April, Karatsu experiences a notable shift in its weather patterns, with precipitation amounting to 115 mm (4.5 in) over approximately 9 days of rain. This marks a decline from March's heavy downpour of 136 mm (5.4 in), indicating a slight easing of the spring rains. Following this trend, May typically brings even more moisture, with 153 mm (6.0 in) expected, suggesting that while April serves as a transitional month, it still plays a crucial role in the overall increase in pre-summer rainfall. As the season progresses, the precipitation days continue to rise, culminating in July’s peak, but April provides a glimpse of the changing weather that characterizes this vibrant coastal region of Japan.
In April, Karatsu, Japan, experiences a noticeable surge in humidity, reaching 79% as the region transitions fully into spring. This increase follows a relatively stable range from January to March, where humidity levels hovered between 69% and 73%. As the month of April unfolds, the rising humidity serves as a precursor to the much more humid months ahead, with May seeing a significant jump to 87%. This trend highlights the gradual warming of the atmosphere, as spring blossoms into summer, and sets the stage for the sultry conditions that define Karatsu's climate during the hotter months.
In April, Karatsu experiences a significant rise in UV exposure, with the UV Index reaching 10, placing it in the very high category. This means residents and visitors need to be mindful of their sun exposure, as the burn time is reduced to just 15 minutes. Following the trend of climbing UV levels from the previous months, April indicates the onset of the more intense sun of spring, signaling the importance of sun protection as the summer months approach. As temperatures rise and outdoor activities increase, it's crucial to stay informed about the UV Index to ensure safety. For more details on UV levels throughout the year, check the Karatsu UV Index.
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As April unfolds its vibrant charm in Karatsu, Japan, the city basks in a delightful 281 hours of sunshine, marking a continued upward trend from the previous months. After starting the year with a modest 178 hours in January, the sun steadily gains strength, culminating in an impressive 305 hours in August. This progression highlights the gradual awakening of spring, as longer, sun-drenched days foster a sense of rejuvenation. Following April, May promises even more sunshine, encouraging residents and visitors alike to embrace the beauty of the season while reveling in the outdoors. The steady increase in sunlight not only enhances the natural landscape but also invigorates the spirit of the community.
In Karatsu, Japan, April brings a 41% chance of sunny weather, marking a slight improvement from the cooler, cloudier months of winter and early spring. This uptick follows March’s 37% likelihood, suggesting a gradual transition towards more favorable weather as the cherry blossoms begin to bloom. However, the sunshine potential dips in May to 33%, indicating a trend where sunny days become less frequent as the rainy season approaches in June. Overall, while April offers a decent opportunity for enjoying outdoor activities under the sun, it’s advisable to keep an eye on the forecast as the month unfolds.
As spring unfolds in Karatsu, Japan, daylight duration increases significantly during April, reaching 13 hours of sunlight. This marks a noticeable shift from the preceding months, where daylight lingered around 10 to 11 hours. The growth in daylight not only brightens the landscape but also heralds the onset of warmer weather, promising longer days ahead. Following April, daylight remains consistent at 13 hours in May and tapers slightly to 14 hours in June, showcasing a delightful progression that fuels outdoor activities and blooming nature. This upward trend in daylight continues throughout the spring and summer, creating an inviting atmosphere for both residents and visitors alike.
As April unfolds in Karatsu, Japan, a gentle breeze sweeps through, with an average wind speed of 4.0 m/s (9 mph). This slight dip from March's 4.1 m/s suggests a transition towards calmer spring days. Interestingly, as the seasons progress, wind speeds generally decline, reaching their lowest in June at 2.7 m/s (6 mph). However, the rejuvenating winds of March and April often invigorate the landscape before giving way to the more tranquil summer months. As autumn approaches, the winds pick back up again, reflecting a seasonal cycle that enchants residents and visitors alike. This rhythmic dance of wind speeds underscores the refreshing charm of Karatsu's spring, drawing in those who appreciate nature's subtler shifts.
Weather in Karatsu varies notably across the year, with each month offering distinct climate conditions. This page compares April’s weather to other months in Karatsu, focusing on differences in temperature, rainfall, humidity, and UV levels.
April and January exhibit notably different weather patterns. In April, temperatures range from a minimum of 7°C (45°F) to a pleasant average of 15°C (59°F), peaking at 24°C (75°F). The month also experiences higher precipitation at 115 mm (4.5 in) over 9 days, contributing to a humid atmosphere with 79% humidity. In contrast, January is colder, with temperatures dipping as low as -1°C (31°F) and averaging around 8°C (46°F), reaching a maximum of 18°C (64°F). Precipitation is less frequent, totaling 69 mm (2.7 in) over the same number of days, and the humidity is slightly lower at 73%. For more detailed information, you can check Karatsu weather in January.
April weather in Karatsu is notably milder than February, with average temperatures rising from 8°C (47°F) in February to a more comfortable 15°C (59°F) in April. The maximum temperatures in April can reach up to 24°C (75°F), compared to February's maximum of 19°C (67°F). Additionally, April experiences higher precipitation levels, with 115 mm (4.5 in) over 9 days, while February sees 84 mm (3.3 in) across 11 days, resulting in slightly higher humidity in April at 79% compared to February's 69%. For a more detailed look at February's weather, visit Karatsu weather in February.
April typically brings milder temperatures compared to March, with minimums around 7°C (45°F) and average highs reaching 24°C (75°F), while March sees slightly cooler conditions with a minimum of 5°C (41°F) and maximums up to 20°C (68°F). Precipitation is also notable in both months, but April experiences a bit less rainfall at 115 mm (4.5 in) over 9 days, compared to March's 136 mm (5.4 in) over 11 days. Additionally, humidity levels rise in April to 79%, slightly higher than March's 71%, contributing to a more humid feel as spring progresses. For a closer look at the weather specifics for March, you can check Karatsu weather in March.
April and May present a notable transition in weather patterns. In April, temperatures range from a minimum of 7°C (45°F) to a maximum of 24°C (75°F), with an average temperature of 15°C (59°F). The month sees around 115 mm (4.5 in) of precipitation over 9 days, accompanied by a humidity level of 79%. In contrast, May experiences warmer conditions, with temperatures fluctuating between a minimum of 11°C (53°F) and a maximum of 27°C (80°F), yielding an average of 19°C (67°F). However, it also brings increased precipitation, totaling 153 mm (6.0 in) across 11 days, alongside a higher humidity level of 87%. This shift highlights the transition towards a more humid, rainy period as spring progresses. For more detailed information about the weather in May, you can check Karatsu weather in May.
April and June present quite different weather patterns. In April, temperatures range from a cool 7°C (45°F) at night to a mild average of 15°C (59°F), peaking at a comfortable 24°C (75°F) during the day. However, the month experiences significant rainfall, with 115 mm (4.5 in) spread over 9 days and humidity levels at 79%. In contrast, June brings a noticeable warmth with minimum temperatures starting at 17°C (63°F), an average of 22°C (73°F), and highs reaching up to 29°C (84°F). The month is also wetter, accumulating 191 mm (7.5 in) of precipitation over 13 days, along with increased humidity at 91%. For a detailed look at June's weather, visit Karatsu weather in June.
In April, the weather is characterized by milder temperatures, with a minimum of 7°C (45°F) and an average of 15°C (59°F), peaking at 24°C (75°F). The month experiences significant rainfall, totaling 115 mm (4.5 in) over about 9 days, with a humidity level of 79%. In contrast, July sees much warmer temperatures, with a minimum of 20°C (68°F) and an average high of 26°C (79°F), reaching as high as 33°C (91°F). The precipitation also increases sharply to 323 mm (12.7 in) over 18 days, paired with a higher humidity level of 97%. For more details on July weather, check out Karatsu weather in July.
April and August present markedly different weather conditions. In April, temperatures range from a cool minimum of 7°C (45°F) to a pleasant maximum of 24°C (75°F), with an average of 15°C (59°F). The month sees around 115 mm (4.5 in) of precipitation over approximately 9 days, with humidity levels at 79%. In contrast, August experiences much warmer temperatures, peaking at a high of 33°C (92°F) and maintaining an average of 28°C (83°F), while the minimum temperature is consistently higher at 21°C (70°F). Precipitation also increases significantly in August, totaling 266 mm (10.5 in) across about 13 days and accompanied by higher humidity at 94%. For more details about the weather specifics in August, you can refer to Karatsu weather in August.
April and September present distinct contrasts in weather. April typically experiences milder temperatures, with averages ranging from a low of 7°C (45°F) to a high of 24°C (75°F), while September enjoys warmer conditions with temperatures that range from a minimum of 19°C (66°F) to a maximum of 32°C (91°F). Additionally, September tends to be wetter, receiving about 210 mm (8.3 in) of precipitation over 16 days compared to April's 115 mm (4.5 in) over 9 days. Humidity levels are also higher in September, averaging 84% compared to April's 79%. For more detailed information about September weather, you can check Karatsu weather in September.
April and October exhibit notable differences in weather patterns, despite similar levels of precipitation. In April, temperatures range from a minimum of 7°C (45°F) to a maximum of 24°C (75°F), with an average of 15°C (59°F) and 9 days of rainfall totaling 115 mm (4.5 in). The humidity remains high at 79%. In contrast, October offers warmer temperatures, with a minimum of 13°C (56°F) and a maximum of 29°C (84°F), averaging 20°C (69°F). Although it experiences slightly less precipitation at 112 mm (4.4 in) over 10 days, the humidity remains consistent at 79%. For a closer look at October weather specifics, you can visit Karatsu weather in October.
April and November share similar average temperatures, with both months featuring a minimum of 7°C (45°F) and an average of around 15°C (59°F). However, April tends to be wetter, receiving 115 mm (4.5 in) of rainfall over about 9 days, compared to November's lighter precipitation of 53 mm (2.1 in) over just 7 days. Additionally, April's humidity is slightly higher at 79%, while November experiences a more comfortable 75%. For those curious about specific conditions in November, more details can be found in this link: Karatsu weather in November.
April boasts a milder and warmer climate than December, with temperatures ranging from a minimum of 7°C (45°F) to an average of 15°C (59°F) and a maximum of 24°C (75°F). In contrast, December sees cooler temperatures, with a minimum of 1°C (35°F), an average of 10°C (50°F), and a maximum of 21°C (71°F). Precipitation is higher in April at 115 mm (4.5 in) over 9 days compared to December's 81 mm (3.2 in) over the same number of days. Additionally, April experiences higher humidity at 79%, while December's humidity is slightly lower at 72%. For a closer look at December weather, you can visit Karatsu weather in December.
April in Karatsu marks a delightful transition into spring, where the weather becomes noticeably milder compared to the chill of winter months. With comfortable temperatures and a significant amount of rainfall, this month often feels refreshing, breathing new life into the blooming landscapes. The high humidity adds a touch of warmth, making outdoor activities particularly enjoyable, despite the occasional rainy day. For those seeking to understand the unique climate characteristics of Karatsu throughout the year, be sure to explore more at Karatsu Climate.