Kapolei (HI) Monthly Rainfall & Precipitation

This page shows both the average monthly rainfall and the number of rainy days in Kapolei, Hawaii, United States of America. Long-term data from 1990 to 2020 was used to calculate these averages. Let's explore the details to provide you with a complete overview.

Kapolei's climate is marked by below-average rainfall, accumulating 377 mm (15 in) of precipitation yearly. The distribution includes a distinct dry season during certain months as shown in the precipitation charts below.

Monthly Precipitation Levels

The average number of days each month with precipitation (> 0.2 mm (0.01 in))

Significant seasonal changes in precipitation occur throughout the year. During the wettest month, December receives substantial rainfall, averaging 53 mm (2.1 in) of precipitation, recorded across 12 rainy days.

In contrast, the driest month, July brings less rainfall, with 15 mm (0.6 in) over 10 rainy days.

December, the wettest month, has a maximum daytime temperature of 26°C (79°F). The city receives 199 hours of sunshine in this period. During the driest month July you can expect a temperature of 28°C (82°F). For more detailed insights into the city's temperatures, visit our Kapolei Temperature page.

Kapolei's average annual precipitation is 377 mm (15 in). Let's compare this to some popular worldwide tourist destinations:

The city of Rome, Italy, has an average annual precipitation of 832 mm (33 in), spread fairly evenly throughout the year.

Meanwhile, Buenos Aires, Argentina, enjoys a humid subtropical climate with 1000 mm (39 in) of annual rainfall, mostly in the summer.

In Brisbane, Australia, the annual precipitation is 979 mm (39 in), making it wetter than Sydney.

Ho Chi Minh City, Vietnam, receives 1955 mm (77 in) of annual rainfall, with a pronounced wet season from May to November, typical of its tropical monsoon climate.

Precipitation amounts are measured using specific gauges installed at weather stations, collecting both rain and snow and any other type of precipitation. Rainfall is measured directly in millimeters, while that from snow and ice is obtained by melting it. Automated systems often incorporate heaters to make this easier.

Information from these stations is transmitted via Wi-Fi, satellite, GPS, or telephone connections to central monitoring networks. This information is immediately updated and integrated into weather models and forecasts.

Climate change is affecting precipitation patterns worldwide, including Kapolei (HI):

• Changing Rainfall Patterns: Global warming causes drastic changes in the patterns of rainfall. Some areas have been experiencing increased frequency and intensity of rainfall, while other areas experience longer dry spells or even droughts.
• Local Impacts: Many regions are experiencing heavier rainfall in the winter months and drier, hotter summers. This affects agriculture, water resources, and ecosystems.

• The U.S. has a significant number of thunderstorms every year, with over 14.6 million taking place across the world annually.
• Approximately 70% of lightning bolts strike land rather than oceans.
• A storm named John was the longest-lasting Pacific tropical storm, continuing for 31 days. As it crossed the dateline twice, it changed status from a hurricane to a typhoon and back to a hurricane.

For more detailed information about Kapolei (HI)'s weather, including sunshine hours, humidity levels, and temperature data, visit our Kapolei (HI) Climate page.