Climate and monthly weather forecastDededo, GU
Climate and monthly weather forecast
The climate of Dededo
Resting in the tropical zone, Dededo in Guam, USA, experiences a tropical rainforest climate that falls under the Af category of the Köppen Climate classification. The weather patterns in this region maintain a relatively static variance throughout the year.The consistent feature of Dededo's climate is the high averages of humidity which hover around 78%. Temperature alterations are quite narrow from the peak of 84.7°F (29.3°C) to the minimal value of 79.7°F (26.5°C). The area's atmospheric pressure varies minutely between 29.79 in and 29.88 in, with only minor fluctuations which don’t tend to affect the overall climate of Dededo in any significant way.
A unique aspect of Dededo's climate is the abundant rainfall throughout the year, with peaks reaching up to 10.28" (261mm) in September followed by 9.76" (248mm) in August. Contrarily, the driest period still holds significant rainfall, from 1.81" (46mm) in March up to 2.83" (72mm) in January. Wind speeds in the area tend to be steady as well, ranging between 9.6mph (15.4km/h) and 16.3mph (26.2km/h), with gusts reaching up to 22.2mph (35.7km/h).
The best time to visit Dededo
Despite the consistent year-round rainfall, Dededo holds favorable conditions for tourists during the early months of the year. February and March although being a part of the drier period seems to offer the most balanced weather conditions. This period brings somewhat reduced rainfall from 2.28" (58mm) to 1.81" (46mm), with relative humidity at 77%. Sunshine hours are at an optimal level of 8.0 hours to 8.1 hours per day, providing ample daylight for exploration and outdoor activities.The worst time to visit Dededo
Planning a visit around the late summer months of August and September might not be the greatest idea due to the high volumes of rainfall, reaching up to 9.76" (248mm) and 10.28" (261mm) respectively. Together with increased cloudiness, this period also holds lower durations of sunshine and therefore, might not be the preferred time for tourists seeking outdoor activities.Spring weather in Dededo
Moving from winter to spring, the temperatures in Dededo take a slight leap from 81.7°F (27.6°C) to 83.3°F (28.5°C) between February and May. Corresponding to this period, the rainfall shows a rise from 2.28" (58mm) to 3.7" (94mm) across the same span. However, the Sunshine hours reach their zenith during spring ranging from 8.1 hours to a striking 10.6 hours per day.Summer weather in Dededo
The summer months from June to August in Dededo exhibit a notable surge in rainfall, with totals skyrocketing from 3.7" (94mm) to 9.76" (248mm). Accompanying this downpour, temperatures remain relatively steady, shifting from 84.7°F (29.3°C) and to 84.4°F (29.1°C). Sunshine hours in these months dwindle from their spring highs to levels between 8.6 and 7.6 hours per day.Autumn weather in Dededo
In Dededo, autumn holds the distinction of having the highest rainfall with 10.28" (261mm) seen in September. Although the precipitation tapers off to 8.46" (215mm) by October, it still remains significantly high. Alongside this, the temperature decreases slightly from 84.4°F (29.1°C) to 82.8°F (28.2°C), and sunshine dips to its yearly low at 6.9 hours per day.Winter weather in Dededo
Through the winter months of November to January, Dededo experiences a decline in rainfall, tapering from 4.69" (119mm) to 2.83" (72mm) respectively. Concurrently, the temperature takes a slight dip to reach 82°F (27.8°C) by January, with sunshine hours experiencing a minor rise from 6.3 to 7.6 hours per day. Therefore, despite it being winter, Dededo maintains its tropical weather, making it a year-round destination.Weather in January
In Dededo, Guam, a welcoming, moderately humid atmosphere characterizes January. The year begins with relatively comforting warmth and average rainfall. Slight movement in temperature from 80.6°F (27°C) to 82°F (27.8°C) can be detected, offering moderate fluctuation throughout the month. Weather in January »Weather in February
Moving into February, Dededo experiences minor adjustments with respect to January. Temperatures slightly fall from 82°F (27.8°C) to 81.7°F (27.6°C) while maintaining a relative humidity of 77%. Rainfall decreases, marking a mildly dry spell as the monthly average rainfall comes in at 2.28" (58mm). Weather in February »Weather in March
March delivers comparable weather conditions to February, embodying tropical delight. A subtle rise in temperatures is experienced, shifting back up to 82°F (27.8°C). It is marked with the same level of relative humidity as January, 78%. Weather in March »Weather in April
April sees a rise in temperature and rainfall from 82°F (27.8°C) to 82.9°F (28.3°C) and 1.81" (46mm) to 2.44" (62mm) respectively. The increase of rain and higher temperatures suggest the coming of a warmer season. While the consistent humidity persists, the increase of daylight hours encourage more outdoor activities. Weather in April »Weather in May
May stands as beginning of the warmest period in the town where mercury levels slightly rise from 82.9°F (28.3°C) to 84.2°F (29°C). As the month progresses, residents notice a significant increase in rainfall that reaches an average of 3.31" (84mm). Weather in May »Weather in June
In June, a distinctive wet season begins for Dededo, Guam. A slight temperature increase to 84.6°F (29.2°C) coincides with a notable increase in rainfall to 3.7" (94mm). Despite increased moisture level, daylight hours reach their peak, providing ample opportunities for outdoor activities. Weather in June »Weather in July
July presents a phenomenal rainfall surge, rising to a peak average of 7.52" (191mm). The temperature slightly steps up to 84.7°F (29.3°C), tying with the forthcoming August for the highest yearly temperature in Dededo. The month's high rainfall gives an added allure to the cascading waterfalls on the island, maximizing their striking beauty. Weather in July »Weather in August
The weather pattern in August maintains a steady course following July with a notable increase in rainfall reaching an unprecedented 9.76" (248mm). Moreover, the temperature ties with the previous month's high at 84.7°F (29.3°C). Weather in August »Weather in September
In Dededo, September carries on the high precipitation trend from August, with rainfall peaking at 10.28" (261mm). A minor decrease in temperature occurs, shifting from 84.7°F (29.3°C) to 84.4°F (29.1°C). This month combines heavy showers with the vibrant tropical sun, creating an intriguing blend of weather conditions. Weather in September »Weather in October
October marks the commencement of a declining phase in precipitation, as the rainfall decreases to 8.46" (215mm). The temperature follows a similar pattern, reducing to 84.2°F (29°C) from 84.4°F (29.1°C). October provides an opportunity to enjoy the pristine beauty of Guam as the weather starts to dry out. Weather in October »Weather in November
As November unfolds in Dededo, the rainfall further drops to 4.69" (119mm). There is a slight decrease in temperature to 83.5°F (28.6°C), providing a gentle cooling effect. As the cooling trend proceeds, November also provides enough sunshine to enjoy the island's attractions comfortably. Weather in November »Weather in December
December brings the year to a close, with temperatures dropping marginally from 83.5°F (28.6°C) to 82°F (27.8°C) and rainfall coming down to 2.99" (76mm). A festive atmosphere engulfs Dededo during these months, with the relatively cooler climate contributing to the cheer. Weather in December »Updated: Aug 11, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
The months with the highest humidity are January, March through May, October through December, with an average relative humidity of 78%.
Throughout the year, there are 288.5 rainfall days, and 60.08" (1526mm) of precipitation is accumulated.
January through August, October through December, with an average maximum UV index of 7, are months with the highest UV index.
February is the month when Dededo sees the average lowest temperatures, with a high of 81.7°F (27.6°C) and a low of 79.7°F (26.5°C).
The month with the least rainfall is March, when the rain falls for 20.2 days and typically collects 1.81" (46mm) of precipitation.
June has the longest days of the year, with an average of 12h and 54min of daylight.
June has the most sunshine of the year, with an average of 10.6h of sunshine.
In Dededo, the warmest months are July and August, registering an average high-temperature of 84.7°F (29.3°C).
With an average relative humidity of 76%, August is the least humid month.
The month with the most rainfall is September, when the rain falls for 28.1 days and typically aggregates up to 10.28" (261mm) of precipitation.
September is the month with the lowest UV index, with an average maximum UV index of 6.
With an average of 6.3h of sunshine, November has the least sunshine of the year.
December has the shortest days of the year, with an average of 11h and 18min of daylight.
Dededo does not utilize Daylight Saving Time (DST). ChST timezone is used over the entire year.
Average temperature
Dededo, GU
The warmest months (with the highest average high temperature) are July and August (84.7°F).
The month with the lowest average high temperature is February (81.7°F).
The month with the highest average low temperature is June (83.3°F).
The coldest month (with the lowest average low temperature) is February (79.7°F).
Average pressure
Dededo, GU
- Average pressure in January:
29.86"Hg - Average pressure in February:
29.88"Hg - Average pressure in March:
29.87"Hg - Average pressure in April:
29.86"Hg - Average pressure in May:
29.85"Hg - Average pressure in June:
29.84"Hg
- Average pressure in July:
29.8"Hg - Average pressure in August:
29.79"Hg - Average pressure in September:
29.79"Hg - Average pressure in October:
29.79"Hg - Average pressure in November:
29.82"Hg - Average pressure in December:
29.83"Hg
The month with the highest atmospheric pressure is February (29.88"Hg).
The months with the lowest atmospheric pressure are August, September and October (29.79"Hg).
Average wind speed
Dededo, GU
- Average wind speed in January:
15.8mph - Average wind speed in February:
16.3mph - Average wind speed in March:
15mph - Average wind speed in April:
13.7mph - Average wind speed in May:
11.7mph - Average wind speed in June:
11.6mph
- Average wind speed in July:
10.3mph - Average wind speed in August:
9.6mph - Average wind speed in September:
9.9mph - Average wind speed in October:
11.2mph - Average wind speed in November:
14.7mph - Average wind speed in December:
15.7mph
The windiest month (with the highest average wind speed) is February (16.3mph).
The calmest month (with the lowest average wind speed) is August (9.6mph).
Average humidity
Dededo, GU
The months with the highest relative humidity are January, March, April, May, October, November and December (78%).
The month with the lowest relative humidity is August (76%).
Average rainfall
Dededo, GU
- Average rainfall in January:
2.83" - Average rainfall in February:
2.28" - Average rainfall in March:
1.81" - Average rainfall in April:
2.44" - Average rainfall in May:
3.31" - Average rainfall in June:
3.7"
- Average rainfall in July:
7.52" - Average rainfall in August:
9.76" - Average rainfall in September:
10.28" - Average rainfall in October:
8.46" - Average rainfall in November:
4.69" - Average rainfall in December:
2.99"
The wettest month (with the highest rainfall) is September (10.28").
The driest month (with the least rainfall) is March (1.81").
Average rainfall days
Dededo, GU
- Average rainfall days in January:
21.3 days - Average rainfall days in February:
17.5 days - Average rainfall days in March:
20.2 days - Average rainfall days in April:
19.3 days - Average rainfall days in May:
23.1 days - Average rainfall days in June:
25.4 days
- Average rainfall days in July:
28.9 days - Average rainfall days in August:
28.9 days - Average rainfall days in September:
28.1 days - Average rainfall days in October:
28.7 days - Average rainfall days in November:
24.3 days - Average rainfall days in December:
22.8 days
The months with the highest number of rainy days are July and August (28.9 days).
The month with the least rainy days is February (17.5 days).
Average daylight / Average sunshine
Dededo, GU
- Average daylight in January:
11h and 24min - Average daylight in February:
11h and 42min - Average daylight in March:
12h and 6min - Average daylight in April:
12h and 24min - Average daylight in May:
12h and 48min - Average daylight in June:
12h and 54min
- Average daylight in July:
12h and 48min - Average daylight in August:
12h and 36min - Average daylight in September:
12h and 12min - Average daylight in October:
11h and 48min - Average daylight in November:
11h and 30min - Average daylight in December:
11h and 18min
The month with the longest days is June (Average daylight: 12h and 54min).
The month with the shortest days is December (Average daylight: 11h and 18min).
- Average sunshine in January:
7h and 36min - Average sunshine in February:
8h and 0min - Average sunshine in March:
8h and 6min - Average sunshine in April:
8h and 30min - Average sunshine in May:
10h and 30min - Average sunshine in June:
10h and 36min
- Average sunshine in July:
8h and 36min - Average sunshine in August:
7h and 36min - Average sunshine in September:
7h and 54min - Average sunshine in October:
6h and 54min - Average sunshine in November:
6h and 18min - Average sunshine in December:
6h and 30min
The month with the most sunshine is June (Average sunshine: 10h and 36min).
The month with the least sunshine is November (Average sunshine: 6h and 18min).
Average sunshine days
Dededo, GU
- Average sunshine days in January:
5.4 days - Average sunshine days in February:
5.8 days - Average sunshine days in March:
6.6 days - Average sunshine days in April:
5.8 days - Average sunshine days in May:
4.3 days - Average sunshine days in June:
2.1 days
- Average sunshine days in July:
1.4 days - Average sunshine days in August:
1.6 days - Average sunshine days in September:
1.1 days - Average sunshine days in October:
1.4 days - Average sunshine days in November:
3.6 days - Average sunshine days in December:
4.7 days
The month with the most sunshine days is March (6.6 days).
The month with the least sunshine days is September (1.1 days).
Average UV index
Dededo, GU
The months with the highest UV index are January, February, March, April, May, June, July, August, October, November and December (UV index 7).
The month with the lowest UV index is September (UV index 6).
Average cloud cover
Dededo, GU
The months with the most cloud cover are January, August and October (Cloud cover 46).
The months with the least cloud cover are May and June (Cloud cover 39).
Average visibility
Dededo, GU
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
