Climate and monthly weather forecast
Guam National Wildlife Refuge, GU

The Guam National Wildlife Refuge, situated in the Pacific Ocean, enjoys a Tropical rainforest climate, encapsulated in the Köppen climate classification as 'Af'. This classification is characterized by high temperatures and heavy rainfall, distributed evenly throughout the year. The year-round climate exhibits minimal temperature fluctuations, with sea temperatures ranging in between 82°F (27.8°C) and 85.4°F (29.7°C). The daylight available at the refuge varies from a low of 11.3 hours to a high of 12.9 hours, with more daylight available during the summer months.

Observed temperature variations are minimal, suggesting a stable and consistent climate. The sea displays a pattern of warming up from January to September, with the highest mean temperature of 85.4°F (29.7°C) recorded in August. It then cools down marginally to reach 83.2°F (28.4°C) in December. In terms of daylight, the highest levels are experienced between May and July, with up to 12.9 hours of sunlight, whereas December has the lowest available daylight at 11.3 hours.

As a prominent feature of the 'Af' climate, constant rainfall is a recurring theme. Therefore, in Guam, there is no designated dry month; generally, rainshowers can be expected throughout the year. This abundant rainfall, coupled with the tropical temperature, results in high humidity creating a rich, verdant landscape.

Considering the ubiquity of rainfall and ongoing high temperature throughout the year, the best time to visit Guam National Wildlife Refuge fundamentally depends on individual preferences. Nonetheless, aiming for the months with the highest average daylight hours, which correspond to May through July, could be advantageous for tourists looking to engage in outdoor activities.

Again, due to consistent rainfall and high temperatures, Guam National Wildlife Refuge does not have a specifically unfavorable period. However, for those sensitive to high humidity and heat, the combination of both during the peak temperature months between July and September might prove uncomfortable.

Spring in Guam National Wildlife Refuge presents a blend of buoyant sea temperatures and increasing daylight hours. The sea temperature rises from 82°F (27.8°C) in March to 84°F (28.9°C) by May, contributing to the warm spring setting. Accompanied by an increasing trend in daylight, from 12.1 hours in March to 12.8 hours in May, it creates ample opportunities for enjoying wildlife and beach activities.

Summertime at the Guam National Wildlife Refuge witnesses the highest sea temperatures, escalating from 84.8°F (29.3°C) in June to 85.4°F (29.7°C) in August. The daylight hours peak at 12.9 in June and steadily decline to 12.6 in August. Despite frequent bouts of rain, it is a popular time to visit due to the ample daylight and warm tropical temperatures.

Autumn continues the patterns of warm sea temperatures, starting at 85°F (29.4°C) in September and gradually declining to 84.5°F (29.2°C) in November. Daylight hours reduce from 12.2 hours in September to 11.5 hours by November. Visitors during this period can still enjoy the engaging aspects of wildlife and scenic beauty of the refuge, in relatively comfortable weather.

Despite being winter, the weather remains warm, with sea temperatures around 83.2°F (28.4°C) in December, the lowest point in the year. Daylight hours continue to decline, with the year's minimum of 11.3 hours in December. The refuge presents a unique winter experience devoid of biting cold, characterized instead by wet and tropical conditions.

January in Guam National Wildlife Refuge reveals a transition out of the rainy season, with less precipitation and clearer skies than the preceding month. As a direct result of these conditions, outdoor activities are more enjoyable and favored by tourists and locals alike. Weather in January »

February continues the dry season trend in Guam National Wildlife Refuge, with milder weather conditions compared to the wet season. The daylight period continues to lengthen, giving tourists and locals additional time for outdoor leisure activities. Weather in February »

Moving into March, Guam National Wildlife Refuge experiences a rise in sea temperature, reaching an average of 82.6°F (28.1°C). This slight increase enhances the allure for water enthusiasts and beachgoers. Longer daylight hours, a trend observed since the start of the year, contribute to an increased interest in outdoor activities. Weather in March »

April welcomes a slight increase in sea temperature. The rise to 82.9°F (28.3°C) typically draws more crowds to the pristine beaches of Guam National Wildlife Refuge. Extended daylight hours yield a longer period for outdoor enjoyment, whether exploring nature trails or engaging in seaside fun. Weather in April »

May signals the transition towards the wet season in the Guam National Wildlife Refuge with slight increases in rainfall. The peak daytime temperature remains relatively high, but the sea temperature scales up to 84°F (28.9°C). Despite the onset of wetter conditions, there remains ample opportunity for tourists and locals to enjoy outdoor pastimes. Weather in May »

June marks the full onset of the wet season in the Guam National Wildlife Refuge even though sea temperature slightly rises to 84.8°F (29.3°C). The increasing precipitation influences the flourishing plant life, offering a remarkable display of vibrant greenery. Weather in June »

July sees a continuation of the wet season in the Guam National Wildlife Refuge, characterized by high precipitation. While the rainfall is notable, daytime temperatures remain high, and the sea reaches an annual high of 85°F (29.4°C). Weather in July »

August, another wet month in the Guam National Wildlife Refuge, experiences the highest sea temperature of the year at a toasty 85.4°F (29.7°C). Despite the downpours, the warm temperatures provide comfort for tourists and locals alike. Weather in August »

September's climate shift is marked by a decline in sea temperature, averaging around 85°F (29.4°C). Despite the wet season continuing, the warmth of the sea still encourages water-based activities such as snorkeling and surfing. Weather in September »

October in the Guam National Wildlife Refuge indicates a retreat from the wet season with reduced rainfall. This shift, combined with a comfortable sea temperature of 85°F (29.4°C), encourages more tourists to visit the island. Weather in October »

As November approaches in the Guam National Wildlife Refuge, there is a noticeable drop in sea temperatures to a cooler 84.5°F (29.2°C). This decrease subtly changes the dynamics of the sea, affecting water activities. Daylight hours further decline, aligning with the trend of shorter days as the year draws to a close. Weather in November »

In December, Guam National Wildlife Refuge experiences the coolest sea temperatures of the year, dropping to 83.2°F (28.4°C). These cooler waters affect marine life, instigating changes in behavior and migration patterns. Daylight reduces further, offering fewer hours for outdoor leisure and activities. Weather in December »