Last updated: April 14, 2025
Guam's climate is characterized by warm temperatures and significant rainfall, making it a tropical paradise. Minimum temperatures hover around 25°C (77°F) in March in Mangilao, while the hottest month is September in Yigo, where maximum temperatures reach 30°C (86°F). Precipitation varies dramatically, with March in Yigo receiving a low of 51 mm (2.0 in), contrasted by the peak rainfall of 405 mm (16.0 in) in August in Mangilao. Humidity levels also fluctuate throughout the year, averaging a minimum of 80% in June and peaking at 84% in December in Mangilao. Overall, Guam's climate offers a blend of warmth and humidity, fostering lush landscapes and vibrant ecosystems.
Guam boasts a consistently warm and tropical climate across its various regions, classified under the Köppen-Geiger climate category Af, indicating a humid tropical climate characterized by high temperatures and significant rainfall throughout the year. From the bustling streets of Agana Heights to the serene shores of Umatac, residents and visitors alike enjoy lush landscapes nurtured by abundant moisture. Whether exploring the vibrant Hagatna, the scenic vistas of Talofofo, or the breathtaking beaches of Merizo, one can always expect a warm, inviting atmosphere and an enchanting tropical experience. From the northern town of Dededo to the southern enclave of Yona, Guam's climate is a key element of its charm, drawing countless visitors to its idyllic shores year-round.
| Climate Zone | Description |
|---|---|
| Af | Tropical rainforest climate with no dry season and high temperatures year-round. |
Guam's temperature remains pleasantly warm throughout the year, with minimal variation between months. From January to December, the minimum temperature typically hovers around 25°C (77°F), while maximum temperatures range from 28°C (83°F) in the cooler months to a peak of 30°C (86°F) during the summer. Notable month-to-month consistency is evident, particularly in Yigo, where highs reach 29°C (84°F) or more from January to April, then one can expect slight increases in June through September. Meanwhile, Mangilao and Talofofo exhibit similar trends, showcasing the island's tropical allure. This warm climate invites visitors year-round, making Guam an ideal destination for those seeking sun and warmth.
Precipitation patterns in Guam reveal a striking seasonal rhythm, with a notable minimum of just 51 mm (2.0 in) recorded in March at Yigo, signaling the dry spell leading into the wetter months. As the island transitions, August stands out with a dramatic peak of 405 mm (16.0 in) in Mangilao. This surge is reflected in the frequency of rainy days, where February sees the least rainfall days—only 14 days in Talofofo—while July experiences the maximum with a full 30 days of rain in Mangilao. Such trends highlight Guam's distinct wet and dry seasons, underscoring how dramatically the island's climate can shift and the implications this has for local ecosystems and daily life.
Guam experiences consistently high humidity throughout the year, with levels typically ranging from a minimum of 80% in June to a peak of 84% in December in Mangilao. This trend illustrates the island's tropical climate, characterized by warm temperatures and moisture-laden air. As humidity levels remain elevated, visitors and residents alike can expect a muggy atmosphere, particularly during the latter part of the year. This consistent humidity not only contributes to the lush vegetation that defines Guam's landscape but also plays a vital role in the overall weather patterns experienced on the island.
In April, both Mangilao and Talofofo experience strikingly high average daily maximum UV Index values of 15, signaling an intense level of ultraviolet radiation in Guam. This consistency in UVI across these two locations highlights a broader trend of elevated sun exposure during this month, underscoring the importance of sun safety in outdoor activities. As residents and visitors alike embrace the island's vibrant outdoor lifestyle, awareness of these UV levels becomes paramount to protect skin and overall health.
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Guam enjoys a delightful amount of sunshine throughout the year, with noticeable variations between the months and locations. In January, both Mangilao and Talofofo bask in around 232 and 233 hours of sunlight, respectively, providing a bright start to the year. As the days warm up in May, sunshine hours significantly increase, showcasing the island's tropical charm, with Talofofo receiving an impressive 335 hours and Mangilao slightly edging ahead at 336 hours. This upward trend in sunlight not only highlights the beautiful weather but also invites outdoor activities and exploration, making Guam a year-round paradise for sun lovers.
In Guam, the likelihood of sunny weather varies significantly throughout the year, showcasing a distinct seasonal trend. For instance, in March, residents and visitors in Yigo can enjoy a promising 64% chance of sunny skies, making it a prime time for outdoor activities and exploration. In stark contrast, August in Mangilao presents a much more challenging scenario, with only a 5% likelihood of sunshine. This fluctuation not only illustrates the changing patterns of Guam's weather but also highlights the importance of planning around these seasonal variations for optimal enjoyment of the island's natural beauty.
In Guam, daylight hours showcase a distinct variation across the seasons. During December, residents of Yigo can expect around 11 hours of daylight, offering a shorter sunlit span that complements the cooler festive season. In contrast, June brings a vibrant 12 hours of daylight to Mangilao, enhancing outdoor activities and beach excursions in the tropical warmth. This trend reflects the island's consistent tropical climate, where longer days in the summer months encourage exploration and enjoyment of Guam's natural beauty.
Agana Heights, Guam, boasts a tropical climate characterized by warm temperatures year-round, with averages hovering around 27°C (81°F). January through March sees minimums of 25°C (77°F) and an occasional peak of 28°C (83°F), while summer months can escalate to 30°C (86°F) in September. Though the islands bask in warmth, they also experience a significant rainy season from June to August, where precipitation can exceed 400 mm (16.0 in) in August alone. Humidity levels remain consistently high, averaging around 80%, creating a lush atmosphere perfect for those seeking vibrant natural beauty. Discover more about the region's weather patterns in detail at Agana Heights climate.
Agat, Guam enjoys a tropical climate with consistently warm temperatures ranging from a mild 25°C (77°F) to a balmy max of 30°C (86°F) throughout the year. The average temperature hovers around 28°C (82°F), making it an ideal destination for sun-seekers. However, visitors should be prepared for the island's significant rainfall, particularly from June to August, when monthly precipitation can exceed 400 mm (16 inches). Humidity remains high, generally between 80-84%, adding a touch of stickiness to the warm air. For a deeper dive into Agat's climate patterns, check out Agat climate.
Nestled in the heart of the Pacific, Asan, Guam boasts a tropical climate characterized by warm temperatures year-round. With monthly averages hovering around 27°C (81°F), you'll hardly find a chilly day, although July and August can see the mercury rise to an inviting 30°C (86°F). Rainfall varies significantly, peaking in late summer with August's impressive 405 mm (16.0 in), while the more moderate months bring around 60-100 mm. The humidity remains consistently high, averaging around 81%, but this only adds to the island's lush, vibrant scenery. For more details, check out the Asan climate.
Nestled in the vibrant landscape of Guam, Barrigada boasts a tropical climate characterized by warm temperatures and seasonal rains. Throughout the year, residents and visitors enjoy averages hovering around 27-28°C (81-82°F), with peak highs reaching 30°C (86°F) during September. While January to April experiences moderate rainfall, the summer months of June to August see a dramatic increase, with August alone recording 405 mm (16.0 in)—perfect for lush greenery but a reminder to stay prepared! Humidity levels remain consistently high, between 80-84%, adding to the tropical allure. For a more detailed look, please visit the Barrigada climate.
Chalan Pago-Ordot, Guam, boasts a tropical climate characterized by warm temperatures year-round. With average highs hovering around 28°C (82°F) and occasional peaks of up to 30°C (86°F) in September, residents and visitors alike can expect consistent warmth. However, the island is not without its rain, especially during August when precipitation can soar to 405 mm (16.0 in)—making it the wettest month. Despite the moisture, humidity levels remain relatively stable, generally floating around 80-84% throughout the year. Whether you're seeking sunny days or a splash of tropical rain, Chalan Pago-Ordot's climate presents a unique blend that's always inviting. For more details, visit Chalan Pago-Ordot climate.
Situated in the heart of the Pacific, Dededo, Guam boasts a tropical climate that offers warmth and humidity year-round. Temperatures typically hover between 25°C and 30°C (77°F to 86°F), ensuring a consistently pleasant atmosphere for beach lovers and outdoor enthusiasts alike. While the months of June through August bring the heaviest rainfall, with averages peaking at 405 mm (16.0 in) in August, the showers often serve to refresh the vibrant landscape rather than detract from the sun-soaked ambiance. The humidity remains elevated, averaging around 80%, contributing to the lush, green surroundings. Discover more about this enchanting climate at Dededo climate.
Nestled in the heart of the Pacific, Hagatna, Guam enjoys a tropical climate characterized by warm temperatures and significant rainfall. Throughout the year, average temperatures hover around a balmy 27°C (81°F), peaking slightly higher in the summer months. Visitors can expect a spectrum of humidity levels, typically around 80-84%, enhancing the lush beauty of the island. However, be prepared for the rainy season, which peaks in August with a staggering 405 mm (16.0 in) of precipitation, making those sunny days even more special. To explore more about the weather patterns and what to expect during your visit, check out the full details on the Hagatna climate.
Inarajan, Guam boasts a consistently warm tropical climate, characterized by average temperatures ranging from a delightful 27°C (81°F) in the cooler months to a toasty 30°C (86°F) during peak summer. Humidity remains high throughout the year, hovering around 80-84%, adding to the island's sultry feel. The rainy season peaks in July and August, with precipitation soaring to 275 mm (10.8 in) and 388 mm (15.3 in) respectively, creating a lush, vibrant landscape. For those looking to explore this breathtaking coastal region, it’s essential to consider the weather; you can find more details on Inarajan climate.
Nestled in the heart of the Pacific, Mangilao, Guam boasts a warm tropical climate that enchants visitors year-round. With average temperatures hovering between 27°C (81°F) and 29°C (84°F), residents and travelers can expect pleasant warmth accompanied by soothing ocean breezes. However, humidity levels remain relatively high, ranging from 80% to 84%, adding a tropical lushness to the air. The rainy season peaks from June to October, where precipitation can soar to an impressive 405 mm (16.0 in) in August, making it a perfect time to embrace the island's vibrant greenery. For more detailed insights, explore the Mangilao climate.
Nestled in the heart of Guam, Merizo experiences a warm tropical climate characterized by consistently mild temperatures year-round. With average highs around 28°C (82°F) and lows near 25°C (77°F), residents and visitors bask in comfortable weather, though the island sees increased rainfall during the summer months, peaking in August with an impressive 388 mm (15.3 in). Humidity levels fluctuate between 80-84%, creating a lush environment that enhances the region's vibrant landscapes. For those looking to explore more about this beautiful locale, detailed insights on its climate can be found here.
Nestled in the vibrant landscapes of Guam, Mongmong-Toto-Maite boasts a tropical climate that remains warm and inviting year-round. Temperatures consistently hover between 25°C (77°F) and 30°C (86°F), with the warmest months peaking in September. During the wet season, particularly from June to August, heavy rainfall transforms the region, with August experiencing over 405 mm (16.0 in) of precipitation. Humidity levels tend to be elevated, ranging from 80% to 84%, creating a lush environment that's characteristic of the island. For a more detailed look at the area's weather patterns, explore the Mongmong-Toto-Maite climate.
Nestled in the tropical heart of Guam, Piti enjoys a warm climate year-round, with temperatures ranging from a comfortable 25°C to 30°C (77°F to 86°F). January through March sees mild days, with averages hovering around 27°C (81°F), while the summer months from June to August bring a rise in both heat and humidity, reaching 29°C (85°F). Rainfall peaks during the summer, with August experiencing the highest precipitation at 405 mm (16.0 in), setting the scene for lush landscapes. Humidity levels remain relatively high, averaging around 80-84%, creating a vibrant, tropical atmosphere that's perfect for outdoor adventures. Discover more about the unique weather patterns in this enchanting region at Piti climate.
Nestled in the tropical embrace of the Pacific, Santa Rita, Guam boasts a remarkably consistent climate, with temperatures ranging from a mild 25°C (77°F) to a warm 30°C (86°F) throughout the year. The island experiences its wettest months from July to August, where rainfall can exceed 400 mm, bringing a lush vibrancy to its stunning landscapes. Despite the humidity hovering around 80% for much of the year, the balmy air invites outdoor adventures year-round. For those who love tropical warmth mixed with the thrill of seasonal rains, Santa Rita offers a captivating experience. To learn more about this enchanting destination, visit Santa Rita climate.
Sinajana, Guam enjoys a tropical climate characterized by consistently warm temperatures throughout the year. With minimums hovering around 25°C (77°F), average highs barely reach 30°C (86°F) in the warmest months of August and September, ensuring a comfortable atmosphere for residents and visitors alike. However, this paradise comes with a significant rainy season; July and August see heavy rainfall, with monthly totals peaking at 405 mm (16.0 in). The humidity stays relatively high, ranging between 80% and 84%, enhancing the lush, vibrant landscapes. For a deeper dive into the local weather patterns, explore the detailed Sinajana climate.
Nestled in the heart of the Pacific, Talofofo, Guam boasts a tropical climate that delights visitors year-round. Average temperatures hover around a pleasant 27-28°C (81-82°F), making it an ideal escape from colder regions. However, be prepared for significant rainfall during the summer months, particularly in August, when precipitation can reach an astonishing 388 mm (15.3 in). Humidity remains consistently high throughout the year, generally floating between 80-84%, contributing to the lush, verdant landscapes that define this beautiful locale. For more details on the weather patterns, check out the full overview of Talofofo climate.
Tamuning, Guam, boasts a tropical climate that's both warm and humid year-round, making it a paradise for sun-seekers. Temperatures generally hover between 25°C (77°F) and 30°C (86°F), with the warmest months being September and October. Rainfall varies significantly, with the peak occurring in August, where it can reach an impressive 405 mm (16.0 in), creating a lush, vibrant landscape. Despite the rains, the high humidity, often around 84%, adds to the tropical allure. For more detailed information, visit the Tamuning climate.
Umatac, Guam enjoys a tropical climate characterized by consistently warm temperatures year-round, with averages hovering around 27°C (81°F). From January to December, the minimum temperatures rarely dip below 25°C (77°F), and highs can reach up to 30°C (86°F), particularly in the summer months. However, this paradise does experience its share of rainfall, especially from June to August, where precipitation can peak at a staggering 388 mm (15.3 in) in August. Despite the humidity staying relatively high, averaging 80-84%, the warmth invites a vibrant lushness to the region's landscapes. For an in-depth look, check out the Umatac climate.
Nestled in the tropics, Yigo, Guam boasts a warm and inviting climate year-round, with average temperatures hovering between 27°C (81°F) and 28°C (82°F). Humidity levels remain high, often around 80–84%, adding to the island’s lush, vibrant environment. While the dry season from January to April sees modest rainfall, the monsoon months from June to October can bring heavy downpours, peaking in August with an impressive 388 mm (15.3 in). This dynamic climate not only nurtures stunning natural landscapes but also offers a unique experience for visitors and locals alike. Explore more about this captivating weather in Yigo at Yigo climate.
Yona, Guam, boasts a tropical climate characterized by warm temperatures year-round, with averages hovering around 27°C (81°F) to 28°C (82°F). While the highs can reach up to 30°C (86°F) in September, even the coolest months stay pleasantly mild, making it a haven for sun-seekers. The region does experience significant rainfall, particularly between June and August, where monthly totals can soar above 400 mm (16 in), leading to lush, vibrant landscapes. With humidity levels lingering around 80%, the air is often thick and warm, wrapping visitors in an immersive tropical embrace. For a more detailed overview, check out the Yona climate.
The climate of Guam showcases a tropical landscape characterized by warm temperatures and significant rainfall throughout the year. With minimum temperatures averaging 25°C (77°F) in March in Mangilao and peaking at 30°C (86°F) in September in Yigo, residents and visitors alike can expect a consistently warm environment. However, the island's precipitation patterns reveal a stark contrast; March experiences a relatively low rainfall of 51 mm (2.0 in) in Yigo, while August can deliver as much as 405 mm (16.0 in) in Mangilao, highlighting the wettest period of the year. Moreover, humidity levels maintain a high percentage, with averages reaching 80% in June and peaking at 84% in December, indicating a consistently muggy atmosphere. This interplay of warmth, moisture, and seasonal shifts shapes Guam's unique climate, contributing to its lush landscapes and vibrant ecosystems.