Spring Weather in Rabaul Papua New Guinea

Daily high temperatures are around 85°F, rarely falling below 83°F or exceeding 87°F. The highest daily average high temperature is 85°F on November 9.

Daily low temperatures are around 80°F, rarely falling below 78°F or exceeding 82°F.

For reference, on November 7, the hottest day of the year, temperatures in Rabaul typically range from 81°F to 85°F, while on August 20, the coldest day of the year, they range from 79°F to 84°F.

The figure below shows you a compact characterization of the hourly average spring temperatures. 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.

San Andrés, Colombia (8,726 miles away) is the far-away foreign place with temperatures most similar to Rabaul (view comparison).

© OpenStreetMap contributors

Compare Rabaul to another city:

CompareMap

The spring in Rabaul experiences increasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy increasing from 76% to 87%.

The clearest day of the spring is September 4, with clear, mostly clear, or partly cloudy conditions 24% of the time.

For reference, on February 4, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 90%, while on August 22, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 25%.

A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Rabaul, the chance of a wet day over the course of the spring is gradually increasing, starting the season at 35% and ending it at 37%.

For reference, the year's highest daily chance of a wet day is 50% on February 8, and its lowest chance is 29% on October 23.

Rainfall

To show variation within the season and not just the monthly totals, we show the rainfall accumulated over a sliding 31-day period centered around each day.

The average sliding 31-day rainfall during the spring in Rabaul is rapidly increasing, starting the season at 4.9 inches, when it rarely exceeds 9.4 inches or falls below 1.2 inches, and ending the season at 6.0 inches, when it rarely exceeds 10.3 inches or falls below 2.6 inches.

The lowest average 31-day accumulation is 4.2 inches on October 22.

Over the course of the spring in Rabaul, the length of the day is gradually increasing. From the start to the end of the season, the length of the day increases by 19 minutes, implying an average daily increase of 13 seconds, and weekly increase of 1 minute, 29 seconds.

The shortest day of the spring is September 1, with 12 hours, 2 minutes of daylight and the longest day is November 30, with 12 hours, 21 minutes of daylight.

The latest sunrise of the spring in Rabaul is 5:50 AM on September 1 and the earliest sunrise is 24 minutes earlier at 5:26 AM on November 11.

The latest sunset is 5:52 PM on September 1 and the earliest sunset is 10 minutes earlier at 5:42 PM on October 25.

Daylight saving time is not observed in Rabaul during 2026.

For reference, on December 21, the longest day of the year, the Sun rises at 5:38 AM and sets 12 hours, 22 minutes later, at 6:00 PM, while on June 21, the shortest day of the year, it rises at 5:56 AM and sets 11 hours, 53 minutes later, at 5:49 PM.

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.

The figure below presents a compact representation of key lunar data for the spring of 2026. 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. The label associated with each bar indicates the date and time that the phase is obtained, and the companion time labels indicate the rise and set times of the Moon for the nearest time interval in which the moon is above the horizon.

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 Rabaul is essentially constant during the spring, remaining around 100% throughout.

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 Rabaul is very rapidly decreasing during the spring, decreasing from 11.3 miles per hour to 6.7 miles per hour over the course of the season.

For reference, on August 13, the windiest day of the year, the daily average wind speed is 11.7 miles per hour, while on November 23, the calmest day of the year, the daily average wind speed is 6.7 miles per hour.

The lowest daily average wind speed during the spring is 6.7 miles per hour on November 23.

The wind direction in Rabaul during the spring is predominantly out of the south from September 1 to September 18, the east from September 18 to November 26, and the west from November 26 to November 30.

Rabaul 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 Rabaul is gradually increasing during the spring, rising by 2°F, from 84°F to 86°F, over the course of the season.

The highest average surface water temperature during the spring is 86°F on November 24.

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 Rabaul 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.

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.

The average accumulated growing degree days in Rabaul are very rapidly increasing during the spring, increasing by 2,902°F, from 1,944°F to 4,846°F, over the course of the season.

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 Rabaul is essentially constant during the spring, remaining within 0.3 kWh of 4.8 kWh throughout.

The highest average daily incident shortwave solar energy during the spring is 5.1 kWh on October 19.

For the purposes of this report, the geographical coordinates of Rabaul are -4.200 deg latitude, 152.164 deg longitude, and 33 ft elevation.

The topography within 2 miles of Rabaul contains very significant variations in elevation, with a maximum elevation change of 1,752 feet and an average elevation above sea level of 275 feet. Within 10 miles contains very significant variations in elevation (2,192 feet). Within 50 miles contains large variations in elevation (6,778 feet).

The area within 2 miles of Rabaul is covered by trees (52%) and water (34%), within 10 miles by water (68%) and trees (24%), and within 50 miles by water (62%) and trees (32%).