Last updated: April 14, 2025
Guernsey’s climate is characterized by mild temperatures and varying precipitation throughout the year. The island experiences a minimum temperature of 0°C (32°F) in March in Castel, peaking at 22°C (72°F) in August, creating a pleasant summer atmosphere. Rainfall presents a marked seasonal pattern, with an average low of 33 mm (1.3 in) in April in Alderney and a notable high of 170 mm (6.7 in) in December. Humidity levels also fluctuate, averaging a comfortable 63% in July in Castel while reaching up to 92% during the wetter months of December in Alderney. Overall, Guernsey's climate offers a unique blend of temperate conditions suitable for both residents and visitors.
Guernsey is characterized by the Cfb climate zone, a mild maritime climate that ensures lush greenery and vibrant flora throughout the islands. This temperate climate is consistent across various locales, from Alderney to Torteval, promoting a rich biodiversity and providing residents with comfortable weather year-round. Areas like Saint Andrew and St Saviour experience cool summers and mild winters, making them ideal for outdoor activities and tourism. With this pleasant climate, Guernsey stands out as a captivating destination where nature and community thrive together.
| Climate Zone | Description |
|---|---|
| Cfb | Oceanic climate with mild temperatures and moderate rainfall year-round. |
Guernsey experiences a delightful range of temperatures throughout the year, with each month showcasing its unique character. Starting in January, the island sees minimums of around 3°C (37°F) and maximums reaching 14°C (57°F), primarily in Torteval. February is notably cooler, with temperatures plummeting to 0°C (33°F) in Castel. As spring approaches, March continues the chilly trend but begins to warm slightly, culminating in maximums of 13°C (56°F). The warmer months of April through September are marked by steadily rising temperatures, peaking at 22°C (72°F) in August. October and November bring a gradual cooling, with temperatures ranging from 8°C (47°F) to 17°C (63°F), while December closes the year with a gentle return to 5°C (41°F) as a minimum. Overall, Guernsey's climate showcases a fascinating transition from brisk winters to pleasantly warm summers, making it a captivating destination all year round.
In Guernsey, precipitation patterns reveal significant seasonal variations, with December being the wettest month, recording up to 170 mm (6.7 in) of rain in Alderney. This trend is mirrored in the number of rainy days, as December also sees the highest frequency, with 21 days of precipitation noted in Castel. Contrastingly, July is the driest month, featuring only 7 days of rain, illustrating a notable decrease in rainfall during the summer. The minimum April rainfall in Alderney drops to 33 mm (1.3 in), highlighting a spring lull before the winter rains return. These patterns underscore the dynamic climate of the region, where the transition from summer to winter dramatically shifts the landscape’s moisture levels.
Guernsey experiences a notable range in humidity levels throughout the year, with notable peaks and troughs that reflect its maritime climate. In July, the humidity dips to a more comfortable 63% in Castel, offering a refreshing respite during the summer months. Conversely, the winter months bring significantly higher humidity, reaching a maximum of 92% in December on Alderney. This trend highlights Guernsey's shift from the uplifting breezes of summer to the dampness of winter, creating a distinct seasonal rhythm that shapes the island's unique character.
In June, both Torteval and Castel experience an average daily maximum UV Index of 9, indicating a consistent trend across these regions in Guernsey. This high UVI signals a significant risk of harm from unprotected sun exposure, emphasizing the necessity for residents and visitors alike to take adequate precautions. As the summer months approach and sun intensity increases, awareness of UV levels becomes essential to ensure safety and promote skin health, making it crucial to regularly monitor local forecasts and adhere to sun safety guidelines.
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Guernsey experiences a fascinating variation in sunshine duration throughout the year. In January, both Torteval and Castel see modest sunlight, clocking in at 105 and 107 hours respectively. However, the sun truly shines in July, where both locations bask in a remarkable 436 hours of sunshine. This dramatic leap from winter to summer highlights the island's vibrant seasonal contrast, inviting sun-seekers to revel in its summer glow.
In Guernsey, the likelihood of sunny weather shows a notable upward trend as the year progresses. For instance, residents in Torteval can expect only a modest 20% chance of sunny days in January, a stark contrast to the 62% likelihood observed in April in Castel. This shift highlights the arrival of spring, bringing increasingly brighter days and more opportunities to enjoy the island's natural beauty. As the seasons change, so too does the promise of sunshine, making Guernsey an enticing destination as the year unfolds.
Daylight hours in Alderney showcase a remarkable transformation throughout the year, creating a dynamic atmosphere for both residents and visitors. In December, the island experiences a brief 8 hours of daylight, inviting a cozy, reflective ambiance that is perfect for winter festivities. As the seasons shift to June, however, Alderney bursts into life with an impressive 16 hours of sunlight, encouraging outdoor activities and vibrant social gatherings. This striking contrast illustrates the seasonal rhythm of the island, where shorter winter days give way to long, sun-drenched summer evenings, enhancing the unique charm of Guernsey's beautiful landscapes.
Alderney, part of Guernsey, boasts a mild maritime climate that captivates visitors with its charm throughout the year. With January temperatures hovering between 3°C and 14°C (37°F to 57°F), and July reaching a comfortable 13°C to 21°C (56°F to 69°F), the weather remains relatively stable. However, frequent rainfall, particularly in October when precipitation peaks at 144 mm (5.7 in), adds a refreshing touch to the island's lush landscapes. Humidity levels can be high, especially from November to January, making for a humid winter atmosphere. For more detailed information, explore the Alderney climate.
Castel, Guernsey, boasts a mild maritime climate that sees temperatures vary from a cool 3°C (37°F) in January to a warm 22°C (72°F) in August. With an average of 89% humidity during the winter months, the area tends to feel quite damp, especially as precipitation peaks in December at 163 mm (6.4 in). Spring and summer bring lighter rains and more comfortable averages, with May and June offering pleasant daytime temperatures and lower humidity levels. The charm of Castel lies not just in its weather but also in its stunning coastal scenery, making it a delightful spot year-round. For more detailed weather patterns, visit Castel climate.
Saint Andrew, Guernsey, enjoys a mild maritime climate characterized by moderately cool temperatures throughout the year. Winter months bring chilly lows around 0°C to 3°C (32°F to 37°F), while summers are pleasantly warm, reaching highs of 21°C to 22°C (70°F to 72°F) in July and August. Precipitation is relatively high, especially in late autumn and winter, with December averaging 163 mm (6.4 in) of rain. The region experiences a notable increase in humidity during these months, often exceeding 90% in winter. For a closer look at the year-round conditions in this charming area, explore the detailed Saint Andrew climate.
Saint Saviour, Guernsey experiences a mild maritime climate characterized by soft winters and cool summers. From the freshness of January, where temperatures hover around 3°C (38°F), to the warmth of August peaking at 22°C (71°F), the seasonality invites a variety of outdoor pursuits. Rainfall is frequent, especially in the autumn, with October witnessing a notable 144 mm (5.7 inches), while summer months like July and August bring a welcome respite with lower precipitation rates. Humidity remains relatively high, especially in the winter months, reaching 90% in November, creating a lush, green landscape year-round. For those curious about the seasonal nuances of this charming locale, more details can be found on Saint Saviour climate.
Nestled in the heart of Guernsey, St Martin experiences a temperate maritime climate characterized by mild temperatures throughout the year. Winter months can be chilly, with January lows dipping to 3°C (37°F), while summer brings comfortable warmth, peaking at 22°C (72°F) in August. Rainfall is most pronounced during the autumn, particularly in October, which can see up to 144 mm (5.7 in) of precipitation. Humidity tends to hover around 90% during the colder months, making the air feel brisk, yet it drops to more pleasant levels in summer. For a detailed overview of seasonal changes, explore the St Martin climate page.
Nestled in the heart of the Channel Islands, St Peter Port, Guernsey enjoys a maritime climate characterized by mild temperatures and variable precipitation throughout the year. Winters are cool, with January's averages hovering around 9°C (49°F), while summers bring warmth, peaking at 21°C (70°F) in July. With an annual humidity range from 63% in July to a peak of 90% in November, the air often feels fresh and invigorating. While rainfall is most abundant in the autumn months, particularly October, the charming landscapes remain lush and vibrant. Discover more about the region's weather patterns at St Peter Port climate.
St Sampson, Guernsey, offers a mild maritime climate characterized by cool winters and pleasantly warm summers. January and February tend to be the coldest months, with temperatures averaging around 9°C (49°F) and considerable humidity hovering above 88%, while July and August bask in highs of 21°C (70°F) to 22°C (72°F), providing the perfect backdrop for outdoor activities. Rainfall is frequent, particularly in October and December, which see over 160 mm (6.4 in) of precipitation, adding to the region’s lush greenery. With its varied weather, St Sampson invites visitors to enjoy its beautiful landscapes under ever-changing skies. For more details, check the St Sampson climate.
Nestled in the picturesque landscapes of Guernsey, Torteval experiences a mild and temperate climate characterized by its distinct seasons. Winters bring crisp temperatures, with January averaging around 9°C (49°F) and cozy, high humidity levels reaching 89%. As spring unfolds, temperatures rise, peaking in summer at a delightful 17°C (63°F) in August, though rainfall is common throughout the year, particularly in October when it reaches 144 mm (5.7 in). With its lush greenery and vibrant flora, the region's climate supports both outdoor adventures and serene escapes. For more detailed weather insights, explore the Torteval climate.
The climate of Guernsey presents a fascinating blend of seasonal contrasts, where temperatures can plummet to 0°C (32°F) in March in Castel, only to rise to a balmy 22°C (72°F) in August. This notable temperature range sets the stage for a vibrant ecosystem, though it’s accompanied by varying precipitation levels. For instance, April in Alderney experiences a modest 33 mm (1.3 in) of rain, while December sees a dramatic spike to 170 mm (6.7 in), marking the wettest month of the year. Humidity levels add another layer to the climate narrative, with July averaging a comfortable 63% in Castel before soaring to 92% in December in Alderney. Together, these elements create a rich tapestry of weather patterns that shape life on the island throughout the year, inviting both residents and visitors to appreciate its unique climatic character.