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Climate and Average Weather Year Round in Kauai Island Hawaii, United States

The climate in Kauai Island is warm, muggy, windy, and mostly clear. Over the course of the year, the temperature typically varies from 67°F to 85°F and is rarely below 61°F or above 86°F.

Based on the beach/pool score, the best time of year to visit Kauai Island for hot-weather activities is from mid May to mid October.

Climate in Kauai Island

warmJanFebMarAprMayJunJulAugSepOctNovDecNowNow79%79%58%58%clearovercastprecipitation: 5.2 inprecipitation: 5.2 in1.0 in1.0 inmuggy: 98%muggy: 98%36%36%beach/pool score: 8.2beach/pool score: 8.25.15.1
Kauai Island weather by month. Click on each chart for more information.

The temperature in Kauai Island varies so little throughout the year that it is not entirely meaningful to discuss hot and cold seasons.

Average High and Low Temperature in Kauai Island

Average High and Low Temperature in Kauai IslandJanFebMarAprMayJunJulAugSepOctNovDec0°F0°F10°F10°F20°F20°F30°F30°F40°F40°F50°F50°F60°F60°F70°F70°F80°F80°F90°F90°F100°F100°FJan 2678°FJan 2678°FSep 385°FSep 385°F67°F67°F76°F76°FJul 583°FJul 583°FOct 1483°FOct 1483°FDec 1079°FDec 1079°FApr 1779°FApr 1779°F75°F75°F74°F74°F70°F70°F70°F70°FNowNow
The daily average high (red line) and low (blue line) temperature, with 25th to 75th and 10th to 90th percentile bands. The thin dotted lines are the corresponding average perceived temperatures.
AverageJanFebMarAprMayJunJulAugSepOctNovDec
High 78°F78°F78°F79°F81°F83°F84°F84°F84°F83°F81°F79°F
Temp. 72°F72°F73°F74°F76°F78°F79°F80°F79°F78°F76°F74°F
Low 67°F67°F68°F70°F72°F74°F75°F76°F75°F74°F72°F69°F

The figure below shows you a compact characterization of the entire year of hourly average temperatures. The horizontal axis is the day of the year, 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 Kauai Island

Average Hourly Temperature in Kauai IslandJanFebMarAprMayJunJulAugSepOctNovDec12 AM12 AM2 AM2 AM4 AM4 AM6 AM6 AM8 AM8 AM10 AM10 AM12 PM12 PM2 PM2 PM4 PM4 PM6 PM6 PM8 PM8 PM10 PM10 PM12 AM12 AMNowNowcomfortablecomfortablecomfortablecomfortablewarm
frigid 15°F freezing 32°F very cold 45°F cold 55°F cool 65°F comfortable 75°F warm 85°F hot 95°F sweltering
The average hourly temperature, color coded into bands. The shaded overlays indicate night and civil twilight.
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© OpenStreetMap contributors

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In Kauai Island, the average percentage of the sky covered by clouds experiences significant seasonal variation over the course of the year.

The clearer part of the year in Kauai Island begins around December 11 and lasts for 4.1 months, ending around April 16.

The clearest month of the year in Kauai Island is January, during which on average the sky is clear, mostly clear, or partly cloudy 78% of the time.

The cloudier part of the year begins around April 16 and lasts for 7.9 months, ending around December 11.

The cloudiest month of the year in Kauai Island is October, during which on average the sky is overcast or mostly cloudy 41% of the time.

Cloud Cover Categories in Kauai Island

Cloud Cover Categories in Kauai IslandclearercloudierJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%Jan 1879%Jan 1879%Oct 1258%Oct 1258%Dec 1168%Dec 1168%Apr 1669%Apr 1669%NowNowclearmostly clearpartly cloudymostly cloudyovercast
0% clear 20% mostly clear 40% partly cloudy 60% mostly cloudy 80% overcast 100%
The percentage of time spent in each cloud cover band, categorized by the percentage of the sky covered by clouds.
FractionJanFebMarAprMayJunJulAugSepOctNovDec
Cloudier 22%24%28%32%31%27%28%28%34%41%37%28%
Clearer 78%76%72%68%69%73%72%72%66%59%63%72%

A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days in Kauai Island varies throughout the year.

The wetter season lasts 7.0 months, from October 5 to May 4, with a greater than 20% chance of a given day being a wet day. The month with the most wet days in Kauai Island is February, with an average of 8.3 days with at least 0.04 inches of precipitation.

The drier season lasts 5.0 months, from May 4 to October 5. The month with the fewest wet days in Kauai Island is June, with an average of 3.7 days with at least 0.04 inches of precipitation.

Among wet days, we distinguish between those that experience rain alone, snow alone, or a mixture of the two. The month with the most days of rain alone in Kauai Island is February, with an average of 8.3 days. Based on this categorization, the most common form of precipitation throughout the year is rain alone, with a peak probability of 30% on December 23.

Daily Chance of Precipitation in Kauai Island

Daily Chance of Precipitation in Kauai IslandwetwetdryJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Dec 2330%Dec 2330%Jun 310%Jun 310%Oct 520%Oct 520%May 420%May 420%NowNowrain
The percentage of days in which various types of precipitation are observed, excluding trace quantities: rain alone, snow alone, and mixed (both rain and snow fell in the same day).
Days ofJanFebMarAprMayJunJulAugSepOctNovDec
Rain 8.7d8.3d7.3d5.7d4.7d3.7d5.1d5.3d5.7d6.9d7.7d8.6d

To show variation within the months and not just the monthly totals, we show the rainfall accumulated over a sliding 31-day period centered around each day of the year. Kauai Island experiences extreme seasonal variation in monthly rainfall.

Rain falls throughout the year in Kauai Island. The month with the most rain in Kauai Island is January, with an average rainfall of 5.2 inches.

The month with the least rain in Kauai Island is June, with an average rainfall of 1.0 inches.

Average Monthly Rainfall in Kauai Island

The average rainfall (solid line) accumulated over the course of a sliding 31-day period centered on the day in question, with 25th to 75th and 10th to 90th percentile bands. The thin dotted line is the corresponding average snowfall.
JanFebMarAprMayJunJulAugSepOctNovDec
Rainfall 5.2″4.9″3.7″3.3″2.1″1.0″1.9″1.9″2.2″3.4″3.8″4.2″

The length of the day in Kauai Island varies over the course of the year. In 2024, the shortest day is December 20, with 10 hours, 47 minutes of daylight; the longest day is June 20, with 13 hours, 29 minutes of daylight.

Hours of Daylight and Twilight in Kauai Island

Hours of Daylight and Twilight in Kauai IslandJanFebMarAprMayJunJulAugSepOctNovDec0 hr24 hr4 hr20 hr8 hr16 hr12 hr12 hr16 hr8 hr20 hr4 hr24 hr0 hr12 hr, 7 minMar 1912 hr, 7 minMar 1913 hr, 29 minJun 2013 hr, 29 minJun 2012 hr, 8 minSep 2212 hr, 8 minSep 2210 hr, 47 minDec 2010 hr, 47 minDec 20nightnightdayNowNow
The number of hours during which the Sun is visible (black line). From bottom (most yellow) to top (most gray), the color bands indicate: full daylight, twilight (civil, nautical, and astronomical), and full night.
Hours ofJanFebMarAprMayJunJulAugSepOctNovDec
Daylight 11.0h11.4h12.0h12.7h13.2h13.5h13.3h12.9h12.2h11.6h11.1h10.8h

The earliest sunrise is at 5:53 AM on June 7, and the latest sunrise is 1 hour, 26 minutes later at 7:19 AM on January 15. The earliest sunset is at 5:53 PM on November 26, and the latest sunset is 1 hour, 32 minutes later at 7:25 PM on July 4.

Daylight saving time (DST) is not observed in Kauai Island during 2024.

Sunrise & Sunset with Twilight in Kauai Island

Sunrise & Sunset with Twilight in Kauai IslandJanFebMarAprMayJunJulAugSepOctNovDec2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AMJun 75:53 AMJun 75:53 AM7:25 PMJul 47:25 PMJul 4Nov 265:53 PMNov 265:53 PM7:19 AMJan 157:19 AMJan 15daynightnightSolarMidnightSolarMidnightSolarNoonSunriseSunsetNowNow
The solar day over the course of the year 2024. From bottom to top, the black lines are the previous solar midnight, sunrise, solar noon, sunset, and the next solar midnight. The day, twilights (civil, nautical, and astronomical), and night are indicated by the color bands from yellow to gray.

The figure below presents a compact representation of the sun's elevation (the angle of the sun above the horizon) and azimuth (its compass bearing) for every hour of every day in the reporting period. The horizontal axis is the day of the year and the vertical axis is the hour of the day. For a given day and hour of that day, the background color indicates the azimuth of the sun at that moment. The black isolines are contours of constant solar elevation.

Solar Elevation and Azimuth in Kauai Island

Solar Elevation and Azimuth in Kauai IslandJanFebMarAprMayJunJulAugSepOctNovDec12 AM12 AM2 AM2 AM4 AM4 AM6 AM6 AM8 AM8 AM10 AM10 AM12 PM12 PM2 PM2 PM4 PM4 PM6 PM6 PM8 PM8 PM10 PM10 PM12 AM12 AM000010101010202020203030303040404040505050606070708000001010101020202020303030304040404050505060606070708045NowNow
northeastsouthwest
Solar elevation and azimuth over the course of the year 2024. The black lines are lines of constant solar elevation (the angle of the sun above the horizon, in degrees). The background color fills indicate the azimuth (the compass bearing) of the sun. The lightly tinted areas at the boundaries of the cardinal compass points indicate the implied intermediate directions (northeast, southeast, southwest, and northwest).

The figure below presents a compact representation of key lunar data for 2024. The horizontal axis is the day, the vertical axis is the hour of the day, and the colored areas indicate when the moon is above the horizon. The vertical gray bars (new Moons) and blue bars (full Moons) indicate key Moon phases.

Moon Rise, Set & Phases in Kauai Island

The time in which the moon is above the horizon (light blue area), with new moons (dark gray lines) and full moons (blue lines) indicated. The shaded overlays indicate night and civil twilight.

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.

Kauai Island experiences extreme seasonal variation in the perceived humidity.

The muggier period of the year lasts for 8.8 months, from April 1 to December 25, during which time the comfort level is muggy, oppressive, or miserable at least 52% of the time. The month with the most muggy days in Kauai Island is August, with 30.4 days that are muggy or worse.

The month with the fewest muggy days in Kauai Island is February, with 11.0 days that are muggy or worse.

Humidity Comfort Levels in Kauai Island

Humidity Comfort Levels in Kauai IslandmuggyJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Feb 1836%Feb 1836%98%Aug 2498%Aug 24Apr 152%Apr 152%Dec 2552%Dec 2552%NowNowoppressiveoppressivemuggymuggyhumidhumidcomfortablecomfortabledrydrymiserablemiserable
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
The percentage of time spent at various humidity comfort levels, categorized by dew point.
JanFebMarAprMayJunJulAugSepOctNovDec
Muggy days 12.9d11.0d13.8d17.0d22.5d28.2d30.4d30.4d29.3d29.0d23.2d17.7d

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 Kauai Island experiences significant seasonal variation over the course of the year.

The windier part of the year lasts for 2.7 months, from June 3 to August 27, with average wind speeds of more than 14.5 miles per hour. The windiest month of the year in Kauai Island is July, with an average hourly wind speed of 16.1 miles per hour.

The calmer time of year lasts for 9.2 months, from August 27 to June 3. The calmest month of the year in Kauai Island is January, with an average hourly wind speed of 12.9 miles per hour.

Average Wind Speed in Kauai Island

Average Wind Speed in Kauai IslandwindyJanFebMarAprMayJunJulAugSepOctNovDec0 mph0 mph2 mph2 mph4 mph4 mph6 mph6 mph8 mph8 mph10 mph10 mph12 mph12 mph14 mph14 mph16 mph16 mph18 mph18 mph20 mph20 mph22 mph22 mphJul 216.3 mphJul 216.3 mphJan 412.8 mphJan 412.8 mphAug 2714.5 mphAug 2714.5 mphNowNow
The average of mean hourly wind speeds (dark gray line), with 25th to 75th and 10th to 90th percentile bands.
JanFebMarAprMayJunJulAugSepOctNovDec
Wind Speed (mph) 12.913.314.515.114.015.516.115.113.713.514.513.9

The predominant average hourly wind direction in Kauai Island is from the east throughout the year.

Wind Direction in Kauai Island

Wind Direction in Kauai IslandJanFebMarAprMayJunJulAugSepOctNovDec0%100%20%80%40%60%60%40%80%20%100%0%NowNoweastnorthwestsouth
northeastsouthwest
The percentage of hours in which the mean wind direction is from each of the four cardinal wind directions, excluding hours in which the mean wind speed is less than 1.0 mph. The lightly tinted areas at the boundaries are the percentage of hours spent in the implied intermediate directions (northeast, southeast, southwest, and northwest).

Kauai Island 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 water temperature experiences some seasonal variation over the course of the year.

The time of year with warmer water lasts for 3.2 months, from July 30 to November 5, with an average temperature above 79°F. The month of the year in Kauai Island with the warmest water is September, with an average temperature of 80°F.

The time of year with cooler water lasts for 3.8 months, from January 5 to April 29, with an average temperature below 76°F. The month of the year in Kauai Island with the coolest water is February, with an average temperature of 75°F.

Average Water Temperature in Kauai Island

Average Water Temperature in Kauai IslandwarmcoolJanFebMarAprMayJunJulAugSepOctNovDec72°F72°F74°F74°F76°F76°F78°F78°F80°F80°F82°F82°FSep 2080°FSep 2080°F75°FFeb 1875°FFeb 18Jul 3079°FJul 3079°FNov 579°FNov 579°FJan 576°FJan 576°FApr 2976°FApr 2976°FNowNow
The daily average water temperature (purple line), with 25th to 75th and 10th to 90th percentile bands.
WaterJanFebMarAprMayJunJulAugSepOctNovDec
Temperature 75°F75°F75°F75°F77°F78°F79°F80°F80°F80°F78°F77°F

To characterize how pleasant the weather is in Kauai Island throughout the year, we compute two travel scores.

The tourism score favors clear, rainless days with perceived temperatures between 65°F and 80°F. Based on this score, the best time of year to visit Kauai Island for general outdoor tourist activities is from early November to mid August, with a peak score in the third week of January.

Tourism Score in Kauai Island

Tourism Score in Kauai Islandbest timebest timeJanFebMarAprMayJunJulAugSepOctNovDec002244668810108.08.06.96.9NowNowtemperaturetemperature cloudscloudsprecipitationprecipitationtourism score
The tourism score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

The beach/pool score favors clear, rainless days with perceived temperatures between 75°F and 90°F. Based on this score, the best time of year to visit Kauai Island for hot-weather activities is from mid May to mid October, with a peak score in the third week of June.

Beach/Pool Score in Kauai Island

Beach/Pool Score in Kauai Islandbest timeJanFebMarAprMayJunJulAugSepOctNovDec002244668810108.28.25.15.1NowNowtemperaturetemperature cloudscloudsprecipitationprecipitationbeach/pool score
The beach/pool score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

Methodology

For each hour between 8:00 AM and 9:00 PM of each day in the analysis period (1980 to 2016), independent scores are computed for perceived temperature, cloud cover, and total precipitation. Those scores are combined into a single hourly composite score, which is then aggregated into days, averaged over all the years in the analysis period, and smoothed.

Our cloud cover score is 10 for fully clear skies, falling linearly to 9 for mostly clear skies, and to 1 for fully overcast skies.

Our precipitation score, which is based on the three-hour precipitation centered on the hour in question, is 10 for no precipitation, falling linearly to 9 for trace precipitation, and to 0 for 0.04 inches of precipitation or more.

Our tourism temperature score is 0 for perceived temperatures below 50°F, rising linearly to 9 for 65°F, to 10 for 75°F, falling linearly to 9 for 80°F, and to 1 for 90°F or hotter.

Our beach/pool temperature score is 0 for perceived temperatures below 65°F, rising linearly to 9 for 75°F, to 10 for 82°F, falling linearly to 9 for 90°F, and to 1 for 100°F or hotter.

Definitions of the growing season vary throughout the world, but for the purposes of this report, we define it as the longest continuous period of non-freezing temperatures (≥ 32°F) in the year (the calendar year in the Northern Hemisphere, or from July 1 until June 30 in the Southern Hemisphere).

Temperatures in Kauai Island are sufficiently warm year round that it is not entirely meaningful to discuss the growing season in these terms. We nevertheless include the chart below as an illustration of the distribution of temperatures experienced throughout the year.

Time Spent in Various Temperature Bands and the Growing Season in Kauai Island

Time Spent in Various Temperature Bands and the Growing Season in Kauai IslandJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%100%Jan 1100%Jan 1100%Jul 2100%Jul 2NowNowcoolcomfortablewarmhot
frigid 15°F freezing 32°F very cold 45°F cold 55°F cool 65°F comfortable 75°F warm 85°F hot 95°F sweltering
The percentage of time spent in various temperature bands. The black line is the percentage chance that a given day is within the growing season.

Growing degree days are a measure of yearly heat accumulation used to predict plant and animal development, and defined as the integral of warmth above a base temperature, discarding any excess above a maximum temperature. In this report, we use a base of 50°F and a cap of 86°F.

Growing Degree Days in Kauai Island

Growing Degree Days in Kauai IslandJanFebMarAprMayJunJulAugSepOctNovDec0°F0°F1,000°F1,000°F2,000°F2,000°F3,000°F3,000°F4,000°F4,000°F5,000°F5,000°F6,000°F6,000°F7,000°F7,000°F8,000°F8,000°F9,000°F9,000°FJan 590°FJan 590°FMar 231,800°FMar 231,800°FDec 319,396°FDec 319,396°FNowNow
The average growing degree days accumulated over the course of the year, with 25th to 75th and 10th to 90th percentile bands.

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 experiences significant seasonal variation over the course of the year.

The brighter period of the year lasts for 4.4 months, from April 14 to August 28, with an average daily incident shortwave energy per square meter above 6.9 kWh. The brightest month of the year in Kauai Island is June, with an average of 7.5 kWh.

The darker period of the year lasts for 2.9 months, from November 4 to February 1, with an average daily incident shortwave energy per square meter below 4.9 kWh. The darkest month of the year in Kauai Island is December, with an average of 4.2 kWh.

Average Daily Incident Shortwave Solar Energy in Kauai Island

Average Daily Incident Shortwave Solar Energy in Kauai IslandbrightdarkdarkJanFebMarAprMayJunJulAugSepOctNovDec0 kWh0 kWh1 kWh1 kWh2 kWh2 kWh3 kWh3 kWh4 kWh4 kWh5 kWh5 kWh6 kWh6 kWh7 kWh7 kWh8 kWh8 kWh9 kWh9 kWhJun 97.6 kWhJun 97.6 kWhDec 144.2 kWhDec 144.2 kWhApr 146.9 kWhApr 146.9 kWhAug 286.9 kWhAug 286.9 kWhNov 44.9 kWhNov 44.9 kWhFeb 14.9 kWhFeb 14.9 kWhNowNow
The average daily shortwave solar energy reaching the ground per square meter (orange line), with 25th to 75th and 10th to 90th percentile bands.
JanFebMarAprMayJunJulAugSepOctNovDec
Solar Energy (kWh) 4.55.36.16.97.47.57.47.16.55.54.64.2

For the purposes of this report, the geographical coordinates of Kauai Island are 22.049 deg latitude, -159.531 deg longitude, and 0 ft elevation.

The topography within 2 miles of Kauai Island is essentially flat, with a maximum elevation change of 0 feet and an average elevation above sea level of 0 feet. Within 10 miles is also essentially flat (0 feet). Within 50 miles is also essentially flat (0 feet).

The area within 2 miles of Kauai Island is covered by trees (62%), shrubs (22%), and herbaceous vegetation (14%), within 10 miles by trees (57%) and shrubs (22%), and within 50 miles by water (92%).

This report illustrates the typical weather in Kauai Island, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016.

The details of the data sources used for this report can be found on the Lihue Airport page.

Disclaimer

The information on this site is provided as is, without any assurances as to its accuracy or suitability for any purpose. Weather data is prone to errors, outages, and other defects. We assume no responsibility for any decisions made on the basis of the content presented on this site.

We draw particular cautious attention to our reliance on the MERRA-2 model-based reconstructions for a number of important data series. While having the tremendous advantages of temporal and spatial completeness, these reconstructions: (1) are based on computer models that may have model-based errors, (2) are coarsely sampled on a 50 km grid and are therefore unable to reconstruct the local variations of many microclimates, and (3) have particular difficulty with the weather in some coastal areas, especially small islands.

We further caution that our travel scores are only as good as the data that underpin them, that weather conditions at any given location and time are unpredictable and variable, and that the definition of the scores reflects a particular set of preferences that may not agree with those of any particular reader.

Please review our full terms contained on our Terms of Service page.