Last updated: January 18, 2025
Shimane, Japan, is characterized by a Cfa climate according to the Koppen-Geiger classification, which signifies a humid subtropical climate. This region experiences a notable temperature range, with minimum winter temperatures plummeting to -12°C (10°F) in February, while summer peaks can reach a sweltering 36°C (98°F) in August. The average annual temperature hovers around 16°C (61°F), showcasing the distinct seasonal variations that define Shimane’s climate and influence its natural landscapes and local weather patterns.
In Shimane, Japan, temperature patterns exhibit distinct seasonal trends that reflect the transition from cold winters to warm summers. January and February are characterized by subzero temperatures, with monthly minimums dropping to -12°C (10°F) in February, while averages remain around 6°C (43°F). As spring approaches in March and April, temperatures begin to rise, reaching a maximum of 28°C (82°F) in late April, indicating the onset of milder conditions. May sees further warming, with average temperatures climbing to 18°C (65°F), and summer months bring considerable heat, peaking in August with maximums hitting 36°C (98°F) and averages around 27°C (81°F). As the year progresses into autumn, September experiences a slight moderation with averages of 24°C (75°F), followed by a gradual cooling into November and December, where temperatures dip back down, closing the annual cycle with December averages around 8°C (48°F) amid winter's return.
Izumo experiences a temperature range from a minimum of -8°C (19°F) in February to a maximum of 36°C (96°F) in August, highlighting its marked seasonal variations monthly temperatures in Izumo. Similarly, Matsue records a minimum of -1°C (30°F) in January and reaches up to 32°C (91°F) in August, showcasing its own diverse climate patterns monthly temperatures in Matsue.
Shimane, Japan, experiences a notable precipitation pattern throughout the year, with distinct variations between seasons. Winter months, particularly January and February, receive consistent rainfall, averaging around 112 mm (4.4 in), with January recording precipitation over 16 days. As spring emerges, March marks a slight uptick in precipitation to 137 mm (5.4 in), while April and May see a decrease, averaging 120 mm (4.7 in) and 103 mm (4.1 in) respectively. These amounts demonstrate a transitional period characterized by relatively moderate rainfall.
The summer months, particularly July and August, present a dramatic spike in precipitation, often linked to the monsoon season, with July receiving the highest monthly total of 286 mm (11.3 in) across 16 days. August follows closely with 234 mm (9.2 in). As the season shifts into autumn, September also remains relatively wet with 227 mm (9.0 in). By contrast, November significantly drops to 63 mm (2.5 in), while December experiences a resurgence in precipitation at 132 mm (5.2 in)—a pattern that highlights Shimane's climatic variability.
In Shimane, Japan, sunshine duration exhibits a clear seasonal progression, with a steady increase in hours from the cold winter months to the warm summer season. January and February are characterized by limited sunshine, recording only 165 hours and 213 hours respectively. However, as spring unfolds, the region experiences a surge in sunlight, culminating in March with 258 hours, and reaching 281 hours in April. May continues this upward trend, boasting 303 hours of sunshine—a promising signal of the impending summer warmth that residents eagerly anticipate.
The summer months truly shine for Shimane, with August standing out as the sunniest month, offering an impressive 306 hours of bright sunshine. This peak contrasts sharply with the shorter days of winter, and even July maintains a robust 285 hours. As autumn arrives, sunshine hours gradually decline, with September recording 255 hours and October dropping further to 244 hours. The trend continues into November and December, where the hours of sunlight dwindle to 225 hours and 195 hours, respectively. This seasonal rhythm highlights not only the warmth of summer but also the stark contrast of light availability throughout the year, shaping the region's climate and lifestyle.
The UV Index in Shimane, Japan, demonstrates a pronounced variation throughout the year, reflecting seasonal changes in sun exposure. January and February see relatively moderate levels, with UV Index readings of 4 and 6 respectively, indicating a moderate to high exposure category. During these months, cautious sun protection is recommended, as the burn time is set at 30 minutes in January and reduced to 25 minutes in February. As spring transitions into summer, the UV Index escalates sharply, with March marking the onset of very high UV levels at 8, leading into April and May where it peaks at 11—designated as extreme exposure.
The peak summer months, July and August, maintain an even higher UV Index of 12, sustaining the extreme category, with a burn time of just 10 minutes. This emphasizes the critical importance of sun protection during the hottest months. As autumn approaches, the UV Index begins to decline, with September measuring 10 (very high) and then tapering to 7 in October (high). By November, the index drops to 5 (moderate), and December sees the lowest levels at 3 (also moderate). This seasonal progression underscores the need for heightened sun protection during the summer months while remaining mindful of varying levels of UV radiation throughout the year.
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Daylight duration in Shimane, Japan, exhibits a clear seasonal rhythm, beginning with shorter days in the winter months. Both January and February feature approximately 10 hours of daylight, providing limited sunlight during the colder season. As spring approaches in March, daylight starts to increase, reaching 11 hours. This upward trend continues into April and May, where daylight stretches to 13 hours and then 14 hours respectively, marking a significant uplift that aligns with the arrival of warmer weather and blooming nature.
The summer months maintain this extended daylight, with July and June consistently offering 14 hours of sunlight. However, as August fades into September, the daylight begins to wane slightly, dropping to 13 hours and then 12 hours as autumn sets in. October brings a further reduction to 11 hours, and by November, daylight returns to 10 hours, characteristic of the impending winter months. December concludes the year with the shortest daylight duration of 9 hours, emphasizing the cyclical nature of light and darkness that shapes daily life in Shimane.
Izumo, Japan, experiences a temperate climate with distinct seasonal variations. Winters can be cold, with January temperatures ranging from -4°C to 15°C and significant precipitation, peaking in July with 290 mm. Summer months are warm, featuring averages around 28°C in August and ample sunshine, offering 304 hours of sunlight that month. The city sees moderate rainfall throughout the year, with a gradual decrease in precipitation during the fall months. For more detailed weather information, visit Izumo climate.
Matsue, Japan experiences a temperate climate characterized by distinct seasonal variations. Winters are cold, with January temperatures averaging around 7°C (45°F) and considerable precipitation, peaking at 143 mm (5.6 in). As spring arrives, temperatures gradually rise, reaching 13°C (56°F) in April, while sunshine increases, especially in May, which boasts 305 hours. Summers are warm and humid, with July highs averaging 25°C (78°F) and significant rainfall of 245 mm (9.7 in). For detailed climate information, visit Matsue climate.
In conclusion, Shimane, Japan, showcases a dynamic interplay of climate, precipitation, sunshine duration, UV index, and daylight throughout the year. The notable seasonal variations in temperature and precipitation highlight the region's humid subtropical character, while the changing daylight and UV index reveal the importance of adapting outdoor activities and sun protection as the seasons progress. Understanding these climatic patterns not only fosters greater awareness of the local environment but also enhances residents' and visitors' experiences, allowing them to fully appreciate the beauty and distinctiveness of Shimane across its varied seasons.