Average Weather in May in Honolulu Hawaii, United States
In Honolulu, the month of May is characterized by gradually rising daily high temperatures, with daily highs increasing by 2°F, from 82°F to 84°F over the course of the month, and rarely exceeding 86°F or dropping below 80°F.
Daily low temperatures increase by 2°F, from 71°F to 73°F, rarely falling below 68°F or exceeding 76°F.
For reference, on August 23, the hottest day of the year, temperatures in Honolulu typically range from 76°F to 87°F, while on January 28, the coldest day of the year, they range from 68°F to 79°F.
Average High and Low Temperature in May
The figure below shows you a compact characterization of the hourly average temperatures for the quarter of the year centered on May. The horizontal axis is the day, the vertical axis is the hour of the day, and the color is the average temperature for that hour and day.
Average Hourly Temperature in May
The month of May in Honolulu experiences gradually decreasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy decreasing from 33% to 27%.
The clearest day of the month is May 31, with clear, mostly clear, or partly cloudy conditions 73% of the time.
For reference, on October 31, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 41%, while on January 18, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 79%.
Cloud Cover Categories in May
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Honolulu, the chance of a wet day over the course of May is rapidly decreasing, starting the month at 15% and ending it at 8%.
For reference, the year's highest daily chance of a wet day is 25% on January 11, and its lowest chance is 6% on June 20.
Probability of Precipitation in May
To show variation within the month and not just the monthly total, we show the rainfall accumulated over a sliding 31-day period centered around each day.
The average sliding 31-day rainfall during May in Honolulu is decreasing, starting the month at 1.2 inches, when it rarely exceeds 3.5 inches, and ending the month at 0.4 inches, when it rarely exceeds 1.1 inches.
Average Monthly Rainfall in May
Over the course of May in Honolulu, the length of the day is gradually increasing. From the start to the end of the month, the length of the day increases by 24 minutes, implying an average daily increase of 48 seconds, and weekly increase of 5 minutes, 37 seconds.
The shortest day of the month is May 1, with 12 hours, 57 minutes of daylight and the longest day is May 31, with 13 hours, 21 minutes of daylight.
Hours of Daylight and Twilight in May
The latest sunrise of the month in Honolulu is 6:00 AM on May 1 and the earliest sunrise is 11 minutes earlier at 5:48 AM on May 31.
The earliest sunset is 6:56 PM on May 1 and the latest sunset is 13 minutes later at 7:09 PM on May 31.
Daylight saving time is not observed in Honolulu during 2017.
For reference, on June 21, the longest day of the year, the Sun rises at 5:50 AM and sets 13 hours, 26 minutes later, at 7:16 PM, while on December 21, the shortest day of the year, it rises at 7:04 AM and sets 10 hours, 50 minutes later, at 5:54 PM.
Sunrise & Sunset with Twilight in May
We base the humidity comfort level on the dew point, as it determines whether perspiration will evaporate from the skin, thereby cooling the body. Lower dew points feel drier and higher dew points feel more humid. Unlike temperature, which typically varies significantly between night and day, dew point tends to change more slowly, so while the temperature may drop at night, a muggy day is typically followed by a muggy night.
The chance that a given day will be muggy in Honolulu is very rapidly increasing during May, rising from 39% to 62% over the course of the month.
For reference, on September 21, the muggiest day of the year, there are muggy conditions 93% of the time, while on March 9, the least muggy day of the year, there are muggy conditions 29% of the time.
Humidity Comfort Levels in May
This section discusses the wide-area hourly average wind vector (speed and direction) at 10 meters above the ground. The wind experienced at any given location is highly dependent on local topography and other factors, and instantaneous wind speed and direction vary more widely than hourly averages.
The average hourly wind speed in Honolulu is essentially constant during May, remaining within 0.3 miles per hour of 7.7 miles per hour throughout.
For reference, on July 3, the windiest day of the year, the daily average wind speed is 8.9 miles per hour, while on January 10, the calmest day of the year, the daily average wind speed is 6.6 miles per hour.
The lowest daily average wind speed during May is 7.4 miles per hour on May 19.
Average Wind Speed in May
Wind Direction in May
Honolulu is located near a large body of water (e.g., ocean, sea, or large lake). This section reports on the wide-area average surface temperature of that water.
The average surface water temperature in Honolulu is essentially constant during May, remaining within 1°F of 77°F throughout.
Average Water Temperature in May
This section discusses the total daily incident shortwave solar energy reaching the surface of the ground over a wide area, taking full account of seasonal variations in the length of the day, the elevation of the Sun above the horizon, and absorption by clouds and other atmospheric constituents. Shortwave radiation includes visible light and ultraviolet radiation.
The average daily incident shortwave solar energy in Honolulu is essentially constant during May, remaining within 0.2 kWh of 7.4 kWh throughout.
Average Daily Incident Shortwave Solar Energy in May
For the purposes of this report, the geographical coordinates of Honolulu are 21.307 deg latitude, -157.858 deg longitude, and 23 ft elevation.
The topography within 2 miles of Honolulu contains significant variations in elevation, with a maximum elevation change of 810 feet and an average elevation above sea level of 79 feet. Within 10 miles contains significant variations in elevation (3,104 feet). Within 50 miles contains large variations in elevation (4,121 feet).
The area within 2 miles of Honolulu is covered by artificial surfaces (72%) and water (22%), within 10 miles by water (47%) and artificial surfaces (24%), and within 50 miles by water (91%).
This report illustrates the typical weather in Honolulu year round, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016.
Temperature and Dew Point
There are 2 weather stations near enough to contribute to our estimation of the temperature and dew point in Honolulu.
For each station, the records are corrected for the elevation difference between that station and Honolulu according to the International Standard Atmosphere , and by the relative change present in the MERRA-2 satellite-era reanalysis between the two locations.
The estimated value at Honolulu is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Honolulu and a given station.
All data relating to the Sun's position (e.g., sunrise and sunset) are computed using astronomical formulas from the book, Astronomical Tables of the Sun, Moon and Planets , by Jean Meeus.
All other weather data, including cloud cover, precipitation, wind speed and direction, and solar flux, come from NASA's MERRA-2 Modern-Era Retrospective Analysis . This reanalysis combines a variety of wide-area measurements in a state-of-the-art global meteorological model to reconstruct the hourly history of weather throughout the world on a 50-kilometer grid.
Land Use data comes from the Global Land Cover SHARE database , published by the Food and Agriculture Organization of the United Nations.
Elevation data comes from the Shuttle Radar Topography Mission (SRTM) , published by NASA's Jet Propulsion Laboratory.
Names, locations, and time zones of places and some airports come from the GeoNames Geographical Database .
Time zones for aiports and weather stations are provided by AskGeo.com .
Maps are © Esri, with data from National Geographic, Esri, DeLorme, NAVTEQ, UNEP-WCMC, USGS, NASA, ESA, METI, NRCAN, GEBCO, NOAA, and iPC.