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Climate and Average Weather Year Round in Alotau Papua New Guinea

The climate in Alotau is warm, oppressive, windy, and overcast. Over the course of the year, the temperature typically varies from 76°F to 85°F and is rarely below 74°F or above 87°F.

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

Climate in Alotau

hotwarmhotJanFebMarAprMayJunJulAugSepOctNovDecNowNow35%35%12%12%overcastprecipitation: 7.1 inprecipitation: 7.1 in3.1 in3.1 inmuggy: 100%muggy: 100%96%96%beach/pool score: 6.3beach/pool score: 6.34.54.5
Alotau weather by month. Click on each chart for more information.

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

Average High and Low Temperature in Alotau

Average High and Low Temperature in AlotauJanFebMarAprMayJunJulAugSepOctNovDec0°F0°F10°F10°F20°F20°F30°F30°F40°F40°F50°F50°F60°F60°F70°F70°F80°F80°F90°F90°F100°F100°FAug 680°FAug 680°FJan 185°FJan 185°F76°F76°F81°F81°FNov 1184°FNov 1184°FMar 2684°FMar 2684°FJun 2081°FJun 2081°FSep 581°FSep 581°F79°F79°F81°F81°F77°F77°F77°F77°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 85°F85°F84°F83°F82°F81°F80°F80°F81°F83°F84°F85°F
Temp. 83°F83°F82°F82°F81°F79°F78°F78°F79°F80°F82°F83°F
Low 81°F81°F81°F80°F79°F78°F76°F76°F77°F78°F80°F81°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 Alotau

Average Hourly Temperature in AlotauJanFebMarAprMayJunJulAugSepOctNovDec12 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 AMNowNowwarmhothot
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.

San Andrés, Colombia (8,917 miles away); Golden Grove, Jamaica (9,280 miles); and Codrington, Antigua & Barbuda (10,228 miles) are the far-away foreign places with temperatures most similar to Alotau (view comparison).

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In Alotau, 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 Alotau begins around May 10 and lasts for 6.1 months, ending around November 14.

The clearest month of the year in Alotau is August, during which on average the sky is clear, mostly clear, or partly cloudy 34% of the time.

The cloudier part of the year begins around November 14 and lasts for 5.9 months, ending around May 10.

The cloudiest month of the year in Alotau is January, during which on average the sky is overcast or mostly cloudy 87% of the time.

Cloud Cover Categories in Alotau

Cloud Cover Categories in AlotauclearercloudiercloudierJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%Aug 1235%Aug 1235%Jan 612%Jan 612%May 1024%May 1024%Nov 1424%Nov 1424%NowNowmostly clearpartly cloudymostly cloudyovercastclear
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 87%87%84%79%76%75%69%66%69%73%77%85%
Clearer 13%13%16%21%24%25%31%34%31%27%23%15%

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

The wetter season lasts 4.5 months, from December 26 to May 10, with a greater than 38% chance of a given day being a wet day. The month with the most wet days in Alotau is February, with an average of 14.4 days with at least 0.04 inches of precipitation.

The drier season lasts 7.5 months, from May 10 to December 26. The month with the fewest wet days in Alotau is August, with an average of 7.8 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 Alotau is February, with an average of 14.4 days. Based on this categorization, the most common form of precipitation throughout the year is rain alone, with a peak probability of 51% on February 11.

Daily Chance of Precipitation in Alotau

Daily Chance of Precipitation in AlotauwetdryJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Feb 1151%Feb 1151%Aug 824%Aug 824%Dec 2638%Dec 2638%May 1038%May 1038%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 14.2d14.4d14.0d12.5d10.9d9.5d8.1d7.8d7.6d7.8d8.0d10.4d

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. Alotau experiences extreme seasonal variation in monthly rainfall.

Rain falls throughout the year in Alotau. The month with the most rain in Alotau is February, with an average rainfall of 7.1 inches.

The month with the least rain in Alotau is July, with an average rainfall of 3.2 inches.

Average Monthly Rainfall in Alotau

Average Monthly Rainfall in AlotauJanFebMarAprMayJunJulAugSepOctNovDec0 in0 in2 in2 in4 in4 in6 in6 in8 in8 in10 in10 in12 in12 inFeb 277.1 inFeb 277.1 inJul 283.1 inJul 283.1 inSep 213.5 inSep 213.5 inNowNow
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 6.4″7.1″6.7″6.1″4.8″4.1″3.2″3.3″3.5″3.4″3.8″4.4″

The length of the day in Alotau does not vary substantially over the course of the year, staying within 43 minutes of 12 hours throughout. In 2024, the shortest day is June 21, with 11 hours, 31 minutes of daylight; the longest day is December 21, with 12 hours, 44 minutes of daylight.

Hours of Daylight and Twilight in Alotau

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 12.7h12.4h12.1h11.9h11.6h11.5h11.6h11.8h12.0h12.3h12.6h12.7h

The earliest sunrise is at 5:25 AM on November 18, and the latest sunrise is 52 minutes later at 6:17 AM on July 12. The earliest sunset is at 5:42 PM on May 27, and the latest sunset is 46 minutes later at 6:28 PM on January 27.

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

Sunrise & Sunset with Twilight in Alotau

Sunrise & Sunset with Twilight in AlotauJanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AMNov 185:25 AMNov 185:25 AM6:28 PMJan 276:28 PMJan 27May 275:42 PMMay 275:42 PM6:17 AMJul 126:17 AMJul 12daySolarMidnightSolarMidnightSolarNoonSunriseSunsetNowNow
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 Alotau

Solar Elevation and Azimuth in AlotauJanFebMarAprMayJunJulAugSepOctNovDec12 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 AM0000101010102020202030303030404040405050505060606060707080000010101010202020203030303040404040505050506060607070805690NowNow
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 Alotau

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.

The perceived humidity level in Alotau, as measured by the percentage of time in which the humidity comfort level is muggy, oppressive, or miserable, does not vary significantly over the course of the year, staying within 2% of 98% throughout.

Humidity Comfort Levels in Alotau

Humidity Comfort Levels in AlotauJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Aug 1396%Aug 1396%100%Feb 23100%Feb 23NowNowmiserablemiserableoppressiveoppressivemuggymuggy
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 31.0d29.0d31.0d30.0d31.0d29.9d30.4d30.0d29.4d30.7d29.9d31.0d

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 Alotau experiences significant seasonal variation over the course of the year.

The windier part of the year lasts for 5.8 months, from May 1 to October 25, with average wind speeds of more than 11.2 miles per hour. The windiest month of the year in Alotau is July, with an average hourly wind speed of 14.1 miles per hour.

The calmer time of year lasts for 6.2 months, from October 25 to May 1. The calmest month of the year in Alotau is January, with an average hourly wind speed of 8.1 miles per hour.

Average Wind Speed in Alotau

Average Wind Speed in AlotauwindyJanFebMarAprMayJunJulAugSepOctNovDec0 mph0 mph2 mph2 mph4 mph4 mph6 mph6 mph8 mph8 mph10 mph10 mph12 mph12 mph14 mph14 mph16 mph16 mph18 mph18 mphJul 3014.4 mphJul 3014.4 mphJan 77.9 mphJan 77.9 mphMay 111.2 mphMay 111.2 mphOct 2511.2 mphOct 2511.2 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) 8.18.28.610.011.913.014.113.913.011.79.88.4

The predominant average hourly wind direction in Alotau varies throughout the year.

The wind is most often from the west for 1.4 months, from January 27 to March 9, with a peak percentage of 35% on February 12. The wind is most often from the east for 4.2 months, from March 9 to July 14 and for 5.0 months, from August 15 to January 14, with a peak percentage of 64% on May 20. The wind is most often from the south for 1.0 months, from July 14 to August 15, with a peak percentage of 55% on July 28.

Wind Direction in Alotau

Wind Direction in AlotauENWESEJanFebMarAprMayJunJulAugSepOctNovDec0%100%20%80%40%60%60%40%80%20%100%0%NowNowwesteastnorthsouth
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).

Alotau 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 4.3 months, from December 8 to April 19, with an average temperature above 83°F. The month of the year in Alotau with the warmest water is February, with an average temperature of 85°F.

The time of year with cooler water lasts for 3.0 months, from July 1 to October 2, with an average temperature below 80°F. The month of the year in Alotau with the coolest water is August, with an average temperature of 79°F.

Average Water Temperature in Alotau

Average Water Temperature in AlotauwarmcoolJanFebMarAprMayJunJulAugSepOctNovDec76°F76°F78°F78°F80°F80°F82°F82°F84°F84°F86°F86°FJan 2785°FJan 2785°F79°FAug 1379°FAug 13Dec 883°FDec 883°FApr 1983°FApr 1983°FJul 180°FJul 180°FOct 280°FOct 280°FNowNow
The daily average water temperature (purple line), with 25th to 75th and 10th to 90th percentile bands.
WaterJanFebMarAprMayJunJulAugSepOctNovDec
Temperature 85°F85°F84°F84°F82°F81°F79°F79°F79°F80°F82°F84°F

To characterize how pleasant the weather is in Alotau 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 Alotau for general outdoor tourist activities is from early July to late September, with a peak score in the second week of August.

Tourism Score in Alotau

Tourism Score in Alotaubest timeJanFebMarAprMayJunJulAugSepOctNovDec002244668810106.36.32.32.3NowNowtemperaturetemperature precipitationprecipitationtourism 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 Alotau for hot-weather activities is from mid May to mid November, with a peak score in the second week of August.

Beach/Pool Score in Alotau

Beach/Pool Score in Alotaubest timeJanFebMarAprMayJunJulAugSepOctNovDec002244668810106.36.34.54.5NowNowtemperaturetemperature 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 Alotau 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 Alotau

Time Spent in Various Temperature Bands and the Growing Season in AlotauJanFebMarAprMayJunJulAugSepOctNovDec0%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 2NowNowwarmhotcomfortable
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 Alotau

Growing Degree Days in AlotauJanFebMarAprMayJunJulAugSepOctNovDec0°F0°F2,000°F2,000°F4,000°F4,000°F6,000°F6,000°F8,000°F8,000°F10,000°F10,000°FJul 490°FJul 490°FAug 2900°FAug 2900°FJun 3011,153°FJun 3011,153°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 some seasonal variation over the course of the year.

The brighter period of the year lasts for 2.5 months, from September 12 to November 27, with an average daily incident shortwave energy per square meter above 5.9 kWh. The brightest month of the year in Alotau is October, with an average of 6.1 kWh.

The darker period of the year lasts for 3.3 months, from April 10 to July 20, with an average daily incident shortwave energy per square meter below 4.8 kWh. The darkest month of the year in Alotau is June, with an average of 4.4 kWh.

Average Daily Incident Shortwave Solar Energy in Alotau

Average Daily Incident Shortwave Solar Energy in AlotaubrightdarkJanFebMarAprMayJunJulAugSepOctNovDec0 kWh0 kWh1 kWh1 kWh2 kWh2 kWh3 kWh3 kWh4 kWh4 kWh5 kWh5 kWh6 kWh6 kWh7 kWh7 kWh8 kWh8 kWhOct 206.2 kWhOct 206.2 kWhJun 214.4 kWhJun 214.4 kWhSep 125.9 kWhSep 125.9 kWhNov 275.9 kWhNov 275.9 kWhApr 104.8 kWhApr 104.8 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) 4.94.74.74.74.54.44.75.35.96.16.05.4

For the purposes of this report, the geographical coordinates of Alotau are -10.315 deg latitude, 150.457 deg longitude, and 36 ft elevation.

The topography within 2 miles of Alotau contains very significant variations in elevation, with a maximum elevation change of 1,532 feet and an average elevation above sea level of 131 feet. Within 10 miles contains very significant variations in elevation (3,566 feet). Within 50 miles also contains extreme variations in elevation (5,984 feet).

The area within 2 miles of Alotau is covered by water (60%), trees (25%), and cropland (11%), within 10 miles by water (48%) and trees (42%), and within 50 miles by water (76%) and trees (20%).

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

Alotau is further than 200 kilometers from the nearest reliable weather station, so the weather-related data on this page were taken entirely from NASA's MERRA-2 satellite-era reanalysis . 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.

The temperature and dew point estimates are corrected for the difference between the reference elevation of the MERRA-2 grid cell and the elevation of Alotau, according to the International Standard Atmosphere .

All data relating to the Sun's position (e.g., sunrise and sunset) are computed using astronomical formulas from the book, Astronomical Algorithms 2nd Edition , by Jean Meeus.

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 airports and weather stations are provided by AskGeo.com .

Maps are © OpenStreetMap contributors.

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.