January Weather in Hagatna, Guam

Last updated: August 21, 2025

January in Hagatna, Guam offers a warm tropical escape, with average temperatures hovering around 27°C (81°F). The month experiences maximum highs reaching 28°C (83°F) and minimum lows dipping to 25°C (77°F), making it a delightful time for visitors. However, with 61 mm (2.4 in) of rainfall spread over 15 days, umbrellas may be a common accessory. The humidity level sits at a steamy 83%, adding to the island’s lush, vibrant atmosphere. Whether you're wandering the historic sites or soaking in the stunning beaches, January’s weather provides a captivating backdrop for exploring all that Hagatna has to offer.

January Temperature in Hagatna

In Hagatna, Guam, January marks the beginning of the year with consistently warm temperatures that set a delightful tone for the island's tropical climate. The minimum temperature lingers around a balmy 25°C (77°F), while the average reaches a comfortable 27°C (81°F). Residents and visitors can enjoy a pleasant maximum of 28°C (83°F), reflecting a stable pattern that is characteristic of Guam's weather throughout the winter months. As the year progresses, temperatures remain relatively steady, with only slight increases noted in the following months, showcasing a mild yet inviting atmosphere perfect for outdoor exploration and relaxation. The consistency in warmth not only enhances the island's charm but also creates an inviting environment year-round.

January Weather in Hagatna: Daily Temperature Highs, Lows, and Averages

The chart illustrates January temperature patterns in Hagatna, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Hagatna, January typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec808080818282828282828281
Data source: Temperature data for Hagatna generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

January Precipitation in Hagatna

In January, Hagatna, Guam experiences a moderate start to the year with precipitation totaling 61 mm (2.4 in) over 15 days, marking one of the lighter months compared to the heavier rainfall that follows. As the year progresses, rainfall begins to increase, with February seeing a slight bump to 77 mm (3.0 in), maintaining the same number of precipitation days. However, the real deluge begins in the warmer months, peaking dramatically in July and August, where rainfall skyrockets to 276 mm (10.9 in) and 405 mm (16.0 in) respectively, accompanied by nearly every day being overcast with rain. This trend of escalating precipitation continues into September and October, solidifying the region's reputation for a tropical climate characterized by intense rainfall. By the time December rolls around, annual precipitation trends reveal that the heavier rainy days have dwindled, resulting in a total of 105 mm (4.1 in) over 22 days, leaving behind a wetter, lush landscape as the year closes.

January Precipitation Trends in Hagatna

The chart displays monthly precipitation patterns in Hagatna, with values for each month alongside January’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how January’s conditions compare to those of other months. In Hagatna, January typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec6177539478159276405375356202105
Data source: Precipitation data for January generated using information from the Copernicus Climate Change Service.
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January Humidity in Hagatna

In January, Hagatna, Guam, experiences high humidity levels at 83%, setting the tone for the month as one of the more humid times of the year. This slight dip from February's 82% gives way to a gradual increase, peaking in March and April at 84%. Interestingly, as the year progresses into the hotter months, humidity remains relatively stable, fluctuating around 80-84% from June to December. This consistency suggests a characteristic tropical climate where moisture is a constant companion, creating a warm and enveloping atmosphere that is typical for the region. Overall, the trends reveal a humid environment, ideal for those who thrive in tropical conditions.

January Average Humidity in Hagatna

This chart illustrates the average monthly humidity levels in Hagatna, with January’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In January, average humidity in Hagatna is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec83%82%84%84%83%80%80%80%81%80%82%84%
Data source: Humidity data for January generated using information from the Copernicus Climate Change Service.

January UV Index in Hagatna

In January, Hagatna, Guam experiences a UV Index of 11, categorizing it as having extreme exposure with a burn time of just 10 minutes. This trend of high UV levels continues through the year, peaking at 15 in both March and April. Notably, while the index fluctuates slightly throughout the months, it remains consistently within the extreme range, reflecting an ongoing need for caution under the tropical sun. Even as the index dips slightly in the cooler months of November and December, it still hovers around an intense 11-12. Residents and visitors alike should be mindful of the sun's power year-round; for more information, visit Hagatna UV Index.

Maximum UV Index Levels in Hagatna for January

The chart shows the monthly maximum UV Index (UVI) for Hagatna in January, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In January, the maximum UV index in Hagatna typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec111315151314141415131211
Data source: Hagatna January UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

January Sunshine in Hagatna

January in Hagatna, Guam, welcomes visitors with 232 hours of sunshine, setting a vibrant tone for the year ahead. As the months progress, the island basks in increasingly radiant days, peaking in May with a dazzling 336 hours of sunlight. The gradual ascent from January through May reflects a steady climb toward summer, while June and July maintain a healthy glow, offering over 300 hours of sunshine each. However, as the year wanes, the sun's embrace softens, with August through October showcasing a decline yet remaining comfortably bright, ranging from 269 to 263 hours. With November and December providing a gentle wrap-up to the year, Hagatna's consistent sunny disposition clearly beckons sunseekers all year long.

Monthly Sunshine Duration in Hagatna: January Highlighted

The January sunshine duration represents the total number of hours Hagatna experiences direct sunlight during the month of January, excluding cloudy or obstructed periods. This chart compares the sunshine duration of January with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec232h267h316h314h336h319h300h269h259h263h280h286h
Data source: Hagatna January Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Hagatna During January

In Hagatna, Guam, January brings a 50% chance of sunny weather, making it a pleasant start to the year. As the winter months progress, the likelihood of sunshine slightly increases in February to 52% before reaching its peak in March at 63%. However, as the weather transitions into the warmer months, a noticeable decline occurs, with April and May showing significantly reduced sunshine probabilities at 38% and 34%, respectively. This downward trend continues into the summer, where sunny days become scarce, dipping to as low as 5% in August. Interestingly, the sunny weather does make a comeback in November, returning to the 50% mark, suggesting that while January offers decent sun, the month of March is ideal for those chasing blue skies before the summer rains set in.

Percentage of Sunny Days in January in Hagatna

The chart illustrates the percentage of sunny days in Hagatna throughout the year, with January highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Hagatna experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec50%52%63%38%34%35%13%5%13%9%50%35%
Data source: Hagatna January chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Hagatna in January

In Hagatna, Guam, January ushers in a consistent 11 hours of daylight, a pattern that holds steady through February. As spring approaches in March, daylight begins to increase, reaching 12 hours and maintaining this longer duration through the summer months of June and August. This period of extended daylight not only enhances outdoor activities but also enriches the vibrant island life. As September rolls around, daylight remains at that comfortable 12-hour mark before tapering back to 11 hours from October through December, marking the end of the year with a return to the shorter days. This rhythm of daylight in Hagatna beautifully reflects the region’s tropical climate, inviting both residents and visitors to enjoy the sun-soaked beauty year-round.

Average Daylight Hours in Hagatna for January

The chart illustrates the variation in daylight duration in Hagatna throughout the year, with January highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec11h 24m11h 41m12h 2m12h 25m12h 44m12h 53m12h 48m12h 32m12h 10m11h 48m11h 29m11h 20m
Data source: Hagatna daylight hours, calculated by summing the hours between sunrise and sunset for each day.

January Winds in Hagatna

In Hagatna, Guam, January kicks off the year with a brisk average wind speed of 8.0 m/s (18 mph), setting a lively tone that echoes through the month. As the year progresses into February, the winds slightly ease, averaging 7.8 m/s (17 mph), but still maintain an invigorating presence. By March, we see a gradual decline in wind speed, dropping to 7.1 m/s (16 mph), hinting at a calming trend that lasts through the warmer months. Remarkably, April experiences a notable dip to 4.9 m/s (11 mph), marking the transition into the milder summer conditions. The winds then fluctuate, peaking again in November at 7.2 m/s (16 mph), before wrapping up the year in December with a familiar return to 8.0 m/s (18 mph). This pattern reveals a dynamic yet predictable wind rhythm, reflective of Hagatna’s unique climate throughout the year.

Average January Wind Speed in Hagatna

The chart displays monthly wind speed patterns in Hagatna, with values for each month shown alongside January's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how January's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec8.0 m/s7.87.14.97.94.75.55.15.05.37.28.0
Data source: Hagatna January wind data, generated using information from the Copernicus Climate Change Service.

How January Weather in Hagatna Compares to Other Months

Weather in Hagatna varies notably across the year, with each month offering distinct climate conditions. This page compares January’s weather to other months in Hagatna, focusing on differences in temperature, rainfall, humidity, and UV levels.

January and February share similar temperature ranges, with both months experiencing a minimum of 25°C (77°F), an average of 27°C (81°F), and a maximum of 28°C (83°F). However, February sees an increase in precipitation, totaling 77 mm (3.0 in) compared to January's 61 mm (2.4 in), while the number of rainy days remains constant at 15. Humidity levels are also nearly identical, with January at 83% and February at 82%. For more detailed information on the weather conditions in Hagatna during February, you can check Hagatna weather in February.

In January, the weather maintains a warm atmosphere with temperatures ranging from a minimum of 25°C (77°F) to a maximum of 28°C (83°F), averaging around 27°C (81°F). During this month, the area experiences 61 mm (2.4 in) of precipitation over 15 days, contributing to a relatively high humidity level of 83%. In contrast, March offers a similar temperature profile, with minimum and maximums also between 25°C and 28°C, averaging at 27°C. However, precipitation slightly decreases to 53 mm (2.1 in) while maintaining the same 15 rainy days, leading to a marginally higher humidity of 84%. For more detailed information, check out Hagatna weather in March.

In January, the weather features a warm climate with temperatures ranging from a minimum of 25°C (77°F) to a maximum of 28°C (83°F), accompanied by an average temperature of 27°C (81°F). However, January experiences a total precipitation of 61 mm (2.4 in) over about 15 days, contributing to a high humidity level of 83%.

Conversely, April shows a slight increase in maximum temperature, reaching up to 29°C (84°F) while maintaining the same minimum and average temperatures as January. The month also sees a rise in precipitation to 94 mm (3.7 in) over about 18 days and a subtle increase in humidity to 84%. Notably, for detailed information on the weather in April, visit Hagatna weather in April.

In January, the weather features a warm temperature range with minimums around 25°C (77°F) and averages reaching 27°C (81°F). Precipitation is significant, with 61 mm (2.4 in) spread over 15 days, and the humidity hovers at a high 83%. Conversely, May sees a slight increase in both temperature and rainfall, with an average temperature of 28°C (82°F) and maximums peaking at 29°C (84°F). Rainfall in May totals 78 mm (3.1 in) over 22 days, while humidity remains consistent at 83%. For more detailed insights, check Hagatna weather in May.

In comparing January and June weather, both months experience similar minimum temperatures, averaging around 25°C (77°F), but June tends to be slightly warmer overall, with an average temperature of 28°C (82°F) compared to January's 27°C (81°F). Precipitation shows a significant increase in June, with 159 mm (6.3 in) over 23 days, contrasted with January’s 61 mm (2.4 in) across 15 days. Humidity remains relatively high in both months, at 83% for January and 80% for June. For more detailed insights, check out Hagatna weather in June.

In comparing the weather between January and July, several notable differences emerge. January features slightly cooler temperatures, with an average of 27°C (81°F) and maximum highs reaching 28°C (83°F), alongside a total precipitation of 61 mm (2.4 in) spread over 15 days. In contrast, July sees slightly warmer conditions, with an average temperature of 28°C (82°F) and maximums peaking at 29°C (85°F). However, July is markedly wetter, experiencing a substantial increase in rainfall to 276 mm (10.9 in) over 30 days, while maintaining a relatively high humidity level of 80%. For further details on July weather patterns, you can check Hagatna weather in July.

In January, the weather in Hagatna features mild temperatures, with a minimum of 25°C (77°F) and an average of 27°C (81°F). The month experiences moderate precipitation, accumulating 61 mm (2.4 in) over 15 days, alongside relatively high humidity at 83%. In contrast, August brings warmer temperatures with a minimum of 25°C (78°F) and an average of 28°C (82°F), peaking at 29°C (85°F). However, August is significantly wetter, receiving 405 mm (16.0 in) of rainfall over 30 days, while humidity remains slightly lower at 80%. For more detailed information, check Hagatna weather in August.

In January, temperatures in Hagatna typically range from a minimum of 25°C (77°F) to a maximum of 28°C (83°F), with an average around 27°C (81°F). The humidity is relatively high at 83%, and there is light rainfall, totaling 61 mm (2.4 in) spread over about 15 days. In contrast, September experiences slightly warmer weather, with temperatures averaging 28°C (82°F) and peaking at 30°C (86°F). However, it is significantly wetter, with precipitation reaching 375 mm (14.8 in) over an impressive 28 days. This slight decrease in humidity to 81% doesn’t alleviate the impact of the increased rainfall. For more specifics on the weather, you can check Hagatna weather in September.

In January, the weather is generally warm, with average temperatures ranging from a minimum of 25°C (77°F) to a maximum of 28°C (83°F). This month experiences about 61 mm (2.4 in) of precipitation over 15 days, with humidity levels at 83%. In contrast, October sees a slight increase in average temperature, with a minimum of 25°C (78°F) and a maximum of 29°C (85°F). However, it is significantly wetter, receiving 356 mm (14.0 in) of rainfall over 29 days, accompanied by a slightly lower humidity of 80%. For more detailed insights, visit Hagatna weather in October.

In January, the weather is warm but slightly less humid, with average temperatures ranging from a minimum of 25°C (77°F) to a maximum of 28°C (83°F). Precipitation is relatively low at 61 mm (2.4 in), occurring on about 15 days. In contrast, November experiences slightly higher temperatures, with averages between 26°C (79°F) and 29°C (85°F), and significantly more rainfall, totaling 202 mm (8.0 in) over 26 days. Humidity levels in November are also just a bit lower at 81%. For more detailed information, you can check Hagatna weather in November.

In comparing the weather between January and December, both months experience warm temperatures, but January is slightly cooler with a minimum temperature of 25°C (77°F) compared to December's 26°C (78°F). The average temperatures are similar, with January averaging 27°C (81°F) and December at 27°C (82°F). However, December sees higher maximum temperatures, reaching 29°C (84°F) versus 28°C (83°F) in January. Additionally, December has significantly more precipitation, totaling 105 mm (4.1 in) over 22 days, while January receives 61 mm (2.4 in) across 15 days, resulting in a drier start to the year. The humidity levels are almost identical, with January at 83% and December slightly higher at 84%. For more specifics on December weather conditions, you can visit Hagatna weather in December.

Compare Hagatna's Climate with Cities Worldwide

Conclusion: What to Expect From January Weather in Hagatna

January in Hagatna offers a mild respite from the often hotter and drier months that follow. With average temperatures hovering around a pleasant 27°C (81°F), the warmth is accompanied by a notable increase in humidity—a characteristic feature of this time of year. Visitors can expect more frequent rain, as January sees an average of 15 days with precipitation, contributing to a total of 61 mm (2.4 in). This increase in moisture creates a lush, vibrant landscape, setting the stage for a unique tropical experience. For those interested in a deeper dive into the climatic dynamics of this region, check out Hagatna Climate.