Southern Highlands Climate

Last updated: January 18, 2025

The Southern Highlands of Papua New Guinea are characterized by a tropical rainforest climate (Köppen-Geiger class Af), showcasing a unique blend of warmth and humidity. With a minimum temperature of 8°C (47°F) recorded in November, the region experiences a mild average of 17°C (62°F) across the year. The climatic extremes peak in December, where maximum temperatures can reach 26°C (79°F), fostering a rich biodiversity and vibrant ecosystem. This distinctive climate not only shapes the local environment but also influences the cultural practices of its inhabitants.

Southern Highlands temperature by month

Temperature patterns in the Southern Highlands of Papua New Guinea reveal a consistent cooling trend during the mid-year months, with minimum temperatures typically ranging from 8°C (47°F) to 11°C (51°F) and average temperatures hovering around 16°C (61°F) in June through August. The region experiences a slight warming as the year progresses, with minimal variability in maximum temperatures around 25°C (77°F). The warmest month is December, with a peak of 26°C (79°F), while November marks the transitional period with its notably lower minimum temperature of 8°C (47°F). Overall, the climate exhibits mild seasonal variations, maintaining a temperate feel year-round and stabilizing around 17°C (63°F) as the average throughout the year.

Monthly Temperatures in Southern Highlands, Papua New Guinea

The chart illustrates Southern Highlands's temperature patterns throughout the year, with values aggregated from various locations across the region. It highlights seasonal variations and temperature changes across the months.
JanFebMarAprMayJunJulAugSepOctNovDec636262626261616161626263
Data source: Southern Highlands temperature data aggregated from multiple regional locations, generated using Copernicus Climate Change Service information.
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The average of daily temperatures (24 hours) calculated across all days in the month.

In Ialibu, temperatures range from a minimum of 8°C (47°F) in November to a maximum of 26°C (79°F) in March, reflecting a mild climate throughout the year (monthly temperatures in Ialibu). Similarly, Mendi experiences a minimum temperature of 10°C (50°F) in June and peaks at 26°C (79°F) in December, offering a comparable temperature profile (monthly temperatures in Mendi).

Precipitation Patterns in Southern Highlands

Precipitation patterns in the Southern Highlands of Papua New Guinea exhibit a notable seasonal rhythm, with March and May being the wettest months, recording 631 mm (24.8 in) and 662 mm (26.1 in) respectively. Conversely, July marks a dip in rainfall with only 386 mm (15.2 in), reflecting a distinct dry spell during the middle of the year. Consistent precipitation is observed throughout the year, contributing to the region’s lush tropical rainforest, with rainfall ranging between 386 mm (15.2 in) in July and 662 mm (26.1 in) in May.

The frequency of rainy days complements this precipitation data, with March featuring the highest number of rainy days (30), indicating a persistent wet climate. January and February also maintain high rainfall days at 25 and 27 respectively, while months like April and October see similarly dense rainfall. This relatively uniform distribution of precipitation secures abundant moisture throughout the year, which is instrumental for sustaining both the diverse ecosystems and the agricultural practices of the local communities.

Monthly Average Precipitation in Southern Highlands, Papua New Guinea

The average monthly precipitation in Southern Highlands, providing insights into seasonal rainfall patterns and the region's precipitation trends throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec549401631657662462386473580638459469
Data source: Southern Highlands precipitation data aggregated from multiple regional locations, generated using Copernicus Climate Change Service information.
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Sunshine Duration in Southern Highlands

In the Southern Highlands of Papua New Guinea, sunshine duration exhibits a distinct seasonal trend, with clear increases as the year progresses. From the beginning of the year, January receives 186 hours of sunshine, gradually rising to a peak of 231 hours in December. Noteworthy is the late-year period from May to December, where sunshine hours consistently trend upward, culminating in October and December, both marked by 226 hours or more. This increase indicates a transition that not only brings warmer temperatures but also enhances the region's vibrant ecosystems, supporting the growth of lush vegetation characteristic of tropical rainforests.

Conversely, the months leading up to the peak sunshine—particularly February through April—show a relatively stable pattern with hours ranging between 201 and 204. The slight dip in sunshine hours during the transition from March to April suggests a brief cloudier phase, but this is quickly followed by an increase as the weather stabilizes. Months like July and August maintain a high sunshine average, both around 226 hours, reinforcing the notion of a favorable climate for outdoor activities and agricultural output during these sun-rich periods. Overall, the evolving sunshine patterns underscore the unique climatic rhythms of the Southern Highlands, inviting both ecological and recreational opportunities.

Monthly Sunshine in Southern Highlands, Papua New Guinea

Monthly sunshine duration represents the total hours of direct sunlight Southern Highlands receives each month, excluding periods when the sun is obscured by clouds or other obstructions.
JanFebMarAprMayJunJulAugSepOctNovDec186h204h202h201h223h222h226h224h207h226h213h231h
Data source: Southern Highlands sunshine duration data aggregated from multiple regional locations, generated using Copernicus Climate Change Service information.

Southern Highlands UV Index Trends

The UV Index in the Southern Highlands of Papua New Guinea presents significant health considerations, particularly during the months of January through April, when levels peak at 18—categorized as extreme. This indicates a critical need for sun protection, with a short burn time of just 10 minutes during these months. The high UV Index not only emphasizes the intensity of solar radiation in this region but also highlights the importance of proactive measures such as sunscreen application, protective clothing, and seeking shade to mitigate risks of skin damage.

As the year progresses into May and beyond, the UV Index shows a gradual decline, dropping to 14 in May and further down to 12 in June. Despite this decrease, the levels remain classified as extreme, maintaining a burn time of 10 minutes throughout the year. Even in the late months of the year, such as October and December, the UV Index stabilizes at around 16, reminding residents and visitors alike that sun safety remains paramount. The consistent high UV levels throughout the year underline the need for ongoing awareness and protective behaviors to ensure health and well-being in this tropical environment.

Monthly Maximum UV Index for Southern Highlands, Papua New Guinea

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in Southern Highlands. It measures the strength of ultraviolet radiation from the sun and helps assess the risk of sunburn and UV-related health issues.
JanFebMarAprMayJunJulAugSepOctNovDec161818171412131516161616
Data source: Southern Highlands UV Index data aggregated from multiple regional locations, generated using Copernicus Climate Change Service information.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

Daylight Hours in Southern Highlands

The Southern Highlands of Papua New Guinea experience relatively consistent daylight duration throughout the year, predominantly featuring 12 hours of daylight from January through March. This equilibrium is characteristic of equatorial regions, where seasonal fluctuations in daylight are minimal. As the year transitions into the cooler months of April through August, daylight hours drop slightly to 11 hours, reflecting a subtle shift that contrasts with the stable, predictable patterns observed earlier in the year.

Following this brief reduction, daylight duration returns to 12 hours in September, indicating another phase of stability as the year draws to a close. The months of October, November, and December mirror this trend, reinforcing the pattern of balanced light exposure that benefits both the local ecosystems and communities. This relatively uniform daylight availability throughout the year supports agricultural practices and contributes to the vibrant biodiversity characteristic of the region's tropical environment.

Average Monthly Daylight Hours in Southern Highlands, Papua New Guinea

This chart shows the total daylight hours Southern Highlands receives each month, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec745h737h727h716h708h705h706h713h723h733h742h747h
Data source: Southern Highlands daylight hours, calculated based on aggregated data for various regional locations, determined by the times between sunrise and sunset.

Climate Highlights of Southern Highlands's Popular Destinations

Ialibu, Papua New Guinea, experiences a temperate climate characterized by mild temperatures and significant rainfall throughout the year. Average temperatures range from a minimum of 8°C (47°F) in November to a maximum of 26°C (79°F) in March, with an overall average around 17°C (62°F). Precipitation is highest from March to April, peaking at 680 mm (26.8 in) in April, while July sees the least rainfall at 323 mm (12.7 in). Sunshine hours are relatively high during the mid-year months, reaching up to 229 hours in July and August. For more details, visit Ialibu climate.

Mendi, Papua New Guinea, experiences a tropical highland climate characterized by moderate temperatures and significant rainfall throughout the year. Average temperatures range from 16°C (61°F) to 17°C (63°F), with maximum temperatures peaking at around 26°C (79°F) in December. Rainfall is plentiful, particularly from May to September, with monthly precipitation often exceeding 600 mm (23.6 in). Mendi benefits from a fair amount of sunshine, especially in the drier months, with July receiving up to 223 hours of sun. For more detailed information, visit Mendi climate.

Conclusion

In conclusion, the Southern Highlands of Papua New Guinea exhibit a unique climatic tapestry characterized by consistent temperature patterns, significant precipitation, high UV Index levels, and stable daylight duration throughout the year. This region's tropical rainforest climate, marked by extreme UV exposure, necessitates ongoing awareness regarding sun safety, especially in the sunniest months. The reliable rainfall and daylight hours create an ideal environment for rich biodiversity and agricultural activities, while the cyclical nature of these climatic elements fosters sustainable living for the communities inhabiting this vibrant landscape. Collectively, these factors highlight the delicate balance of the Southern Highlands' ecosystem, underscoring the importance of environmental stewardship and informed practices to preserve this unique region.

Discover the Climate of Southern Highlands's Places

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