Last updated: August 21, 2025
August in Hagatna, Guam presents a warm and humid tropical climate, with temperatures reaching a maximum of 29°C (85°F) and an average of 28°C (82°F). The minimum temperature hovers around 25°C (78°F), providing a consistently mild atmosphere. This month experiences significant rainfall, totaling 405 mm (16.0 in) across 30 days, making it one of the wetter periods of the year. With humidity levels around 80%, visitors can expect a lush, vibrant environment, perfect for enjoying the island's natural beauty amidst the warm, tropical rains.
In August, Hagatna, Guam experiences warm and consistent temperatures, with a minimum of 25°C (78°F) and a maximum that reaches up to 29°C (85°F). The average temperature hovers around 28°C (82°F), mirroring the tropical warmth experienced throughout the summer months. This steadfast warmth follows a trend seen since April, where temperatures remain relatively stable, indicative of Guam's pleasant tropical climate. With mild nighttime temperatures and daytime highs, August offers a perfect backdrop for outdoor adventures and beach activities, while maintaining the same inviting atmosphere that characterizes the alluring island life year-round.
August in Hagatna, Guam, sees a dramatic peak in precipitation, with a staggering 405 mm (16.0 in) of rain recorded, making it the wettest month of the year. This deluge occurs over 30 days, reflecting the island’s tropical climate and the onset of the monsoon season. The volume of rainfall nearly ties with July's total, which records 276 mm (10.9 in), yet the intensity marks August as a standout month. Following the trend of increasing precipitation from June onward, August serves as a vivid reminder of Guam's lush, verdant landscapes shaped by consistent rainfall. The increasing number of wet days, particularly in July and August, underscores a robust rainy season, crucial for the island's ecosystems and water supply.
In Hagatna, Guam, August typically sees a humidity level of 80%, marking a continuation of the trend established during the summer months. As the island transitions from the rainier season, humidity levels begin to stabilize, showing a slight dip from the higher percentages observed earlier in the year. Despite the decrease, this figure remains consistent with June and July, suggesting a humid maritime climate is a defining characteristic throughout late summer. As the year progresses into the fall, humidity gradually rises again in September. This pattern highlights the seasonal variability of humidity in Hagatna, where the peaks and valleys of atmospheric moisture create a richly tropical environment.
In August, Hagatna, Guam, maintains a UV Index of 14, which falls under the extreme exposure category, meaning that just 10 minutes of unprotected sun exposure can lead to skin damage. This month continues the trend seen since June, where the UV Index has consistently hovered around 14 or higher, reflecting a steady intensity of sunlight typical for the region during summer. Notably, from January through May, the UV levels were slightly lower but still classified as extreme, peaking in March and April at 15. As we move from August into the subsequent months, September is poised to increase to a UV Index of 15, highlighting a persistent pattern of intense solar radiation. For those planning outdoor activities, it's crucial to take protective measures against the sun's harsh rays during this time. For more information, check out the detailed Hagatna UV Index.
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In Hagatna, Guam, August experiences a delightful 269 hours of sunshine, contributing to a vibrant summer atmosphere. The month follows a trend of long sunny days seen throughout the year, peaking in May with 336 hours, then gradually tapering down as the year progresses. After a robust July with 300 hours, August still holds its own amidst the fading summer glow. Interestingly, while it may not reach the heights of the warmer months, the consistently high sunshine levels, especially compared to September's 259 hours, ensure that residents and visitors alike can enjoy the island's natural beauty, setting a warm and inviting backdrop for late summer adventures.
In Hagatna, Guam, the likelihood of sunny weather takes a significant dive in August, with only a 5% chance of sunshine, making it one of the cloudiest months of the year. This trend starkly contrasts with the preceding months, where March boasts a robust 63% chance of sun, gradually declining as summer approaches. By July, the chances plummet to just 13%, foreshadowing the heavy overcast conditions typical in August. As the year unfolds, the chances of sunny days fluctuate, but August remains notably dim, hinting at the challenges of planning outdoor activities during this sultry month.
In Hagatna, Guam, August enjoys a delightful 12 hours of daylight, continuing the summer trend established in the preceding months. The daylight duration remains consistent from March through August, offering longer, sun-drenched days that invite outdoor activities and relaxation. As the year progresses towards autumn, daylight begins to taper off in September, returning to 11 hours by October. This stability in daylight duration during the summer months enhances the island’s vibrant atmosphere, making it an ideal time for visitors and locals alike to bask in the tropical sun. The seamless transition from vibrant summer days to shorter fall evenings is a hallmark of Guam's unique climate, capturing the essence of island life.
In Hagatna, Guam, the August wind brings a gentle breeze averaging 5.1 m/s (11 mph), marking a slight dip compared to the windier months earlier in the year. Following a peak in January and December at 8.0 m/s (18 mph), the wind speeds begin to wane during the summer months, with August reflecting a continuation of this trend. This seasonal fluctuation showcases the island's transition from the more vigorous gales of winter to the milder summer air, setting the stage for the calm and serene atmosphere that defines late summer in the region. As the time transitions to September, the winds remain consistent, reinforcing a tranquil tropical experience perfect for relaxation by the coastline.
Weather in Hagatna varies notably across the year, with each month offering distinct climate conditions. This page compares August’s weather to other months in Hagatna, focusing on differences in temperature, rainfall, humidity, and UV levels.
When comparing the weather in August and January, both months experience relatively warm temperatures, but with notable differences. In August, temperatures range from a minimum of 25°C (78°F) to a maximum of 29°C (85°F), with an average of 28°C (82°F). This month also sees significant rainfall, with 405 mm (16.0 in) of precipitation over 30 days, resulting in high humidity levels of around 80%.
In contrast, January presents slightly cooler temperatures, with minimums at 25°C (77°F) and maximums at 28°C (83°F), averaging 27°C (81°F). Rainfall is considerably less, with only 61 mm (2.4 in) spread across 15 days, and humidity is marginally higher at 83%. This reduction in rain and milder temperatures make January a more pleasant month for outdoor activities. For more detailed information about January weather, visit Hagatna weather in January.
In comparing the weather between August and February, we see some notable differences despite their similar warm temperatures. August experiences a higher average temperature, peaking around 29°C (85°F) and with significant precipitation totaling 405 mm (16.0 in) over 30 days, resulting in a distinctly humid atmosphere at 80%. In contrast, February is slightly cooler with an average temperature of 27°C (80°F) and a much lower rainfall of 77 mm (3.0 in) spread across 15 days, coupled with a humidity level of 82%. This makes February generally drier and more comfortable compared to the intense rainfall and stickiness of August. For more detailed insights, you can refer to Hagatna weather in February.
In comparing August and March weather, both months experience warm temperatures with minimal variation. August sees a minimum temperature of 25°C (78°F) and has an average of 28°C (82°F), peaking at 29°C (85°F). In contrast, March maintains similar temperatures, starting at a minimum of 25°C (77°F) and averaging 27°C (81°F), with a maximum of 28°C (83°F). However, the two months differ significantly in terms of precipitation; August receives a hefty 405 mm (16.0 in) over 30 days, while March experiences only 53 mm (2.1 in) over 15 days. Humidity levels are also comparable, with August at 80% and March slightly higher at 84%. For more details on March weather, visit Hagatna weather in March.
When comparing the weather in August and April, we find notable differences in both precipitation and humidity. August features a slightly higher average temperature of 28°C (82°F) and experiences significantly more rainfall, with 405 mm (16.0 in) over 30 days, compared to April's 94 mm (3.7 in) over just 18 days. Both months have similar maximum temperatures, but April has a slightly lower minimum temperature of 25°C (77°F), and its humidity sits at 84%, marginally above August's 80%. For more detailed weather information, you can refer to Hagatna weather in April.
In comparing the weather in August to that in May, both months share similar temperature ranges, with daily averages around 28°C (82°F) and maximum temperatures peaking at 29°C (84°F to 85°F). However, August is significantly wetter, experiencing an average precipitation of 405 mm (16.0 in) over 30 days compared to May's 78 mm (3.1 in) across 22 days. Humidity levels are also slightly lower in August at 80%, compared to 83% in May, making August feel a bit more oppressive despite its higher rainfall. For more detailed information about May weather, you can check Hagatna weather in May.
August and June exhibit similar temperature patterns, with both months averaging around 28°C (82°F) and experiencing a minimum of 25°C (78°F) and a maximum of 29°C (85°F). However, August is notably wetter, receiving 405 mm (16.0 in) of precipitation over 30 days, compared to June's 159 mm (6.3 in) over just 23 days. Both months maintain a high humidity level of 80%, but the increase in rainfall during August makes it a significantly wetter period. For a closer look at the weather conditions in June, check out Hagatna weather in June.
In comparing the weather of August and July, we observe that both months maintain similar temperature profiles, with minimums around 25-26°C (78°F), averages at 28°C (82°F), and maximums reaching 29°C (85°F). However, August is significantly wetter, receiving 405 mm (16.0 in) of precipitation compared to July's 276 mm (10.9 in), despite both months having the same number of rainy days. Humidity levels remain constant at 80% throughout both months. For a closer look at the weather specifics in July, you can visit Hagatna weather in July.
In comparing the weather of August and September, both months exhibit warm temperatures with a similar daily range, where August sees a minimum of 25°C (78°F) and an average of 28°C (82°F), while September maintains the same minimum but slightly increases the maximum to 30°C (86°F). August experiences higher precipitation, measuring 405 mm (16.0 in) over 30 days, compared to 375 mm (14.8 in) across 28 days in September. Humidity levels remain comparable, with August averaging 80% and September at 81%, indicating a consistently humid environment throughout both months. For more specific weather details, you can visit Hagatna weather in September.
In both August and October, the weather remains quite similar, with average daily temperatures hovering between 25°C (78°F) and 29°C (85°F). However, October experiences slightly less precipitation at 356 mm (14.0 in) compared to August's 405 mm (16.0 in), reflecting a marginal decrease in rainfall despite both months having high humidity levels of 80%. Additionally, while August sees rainfall on 30 days, October has slightly less, with rain occurring on 29 days. This means that while both months are warm and humid, October offers a touch drier experience. For a more detailed look at October weather specifics, you can check Hagatna weather in October.
In August, the weather is marked by a minimum temperature of 25°C (78°F) and an average of 28°C (82°F), with a maximum reaching 29°C (85°F). This month experiences considerable rainfall of 405 mm (16.0 in) over 30 days, coupled with high humidity at 80%. In contrast, November sees a similar temperature range, with a minimum of 26°C (79°F) and an average and maximum both at 28°C (82°F) and 29°C (85°F), respectively. However, precipitation drops significantly to 202 mm (8.0 in) across 26 days, with humidity slightly higher at 81%. For more details, you can check the Hagatna weather in November.
When comparing the weather in August and December, both months showcase warm temperatures with averages around 28°C (82°F); however, August tends to be slightly wetter and more humid. In August, the minimum temperature is 25°C (78°F), while December's minimum is marginally higher at 26°C (78°F). With 405 mm (16.0 in) of precipitation over 30 days, August is significantly rainier compared to December’s 105 mm (4.1 in) over 22 days. Additionally, December experiences a higher humidity level at 84%, compared to August’s 80%. For more detailed insights, you can visit Hagatna weather in December.
In August, Hagatna experiences a unique blend of warmth and moisture that sets it apart from other months. The temperatures consistently hover around a comfortable 28°C (82°F), creating an inviting atmosphere, while the high humidity levels at 80% contribute to a lush environment. However, this month is also marked by significant rainfall, with 405 mm (16.0 in) spread over 30 days, making it the wettest time of the year. This combination of warmth and frequent showers cultivates a vibrant tropical landscape, perfect for those who appreciate the beauty of a lush, green paradise. For more insights on Hagatna's weather patterns throughout the year, visit Hagatna Climate.