Climate and monthly weather forecast
Sibu, Malaysia

Located in the heart of the tropical geography of Malaysia, Sibu experiences a predominant 'Af' or Tropical rainforest climate according to the Köppen climate classification. Notable for its consistently high temperatures and regular occurrences of rain throughout the year, the climate remains relatively stable with minor variations in weather parameters scattered across the year.

The temperature largely hovers between highs of 31.2°C (88.2°F) to 33°C (91.4°F) and lows within the range of 22.5°C (72.5°F) to 23.1°C (73.6°F). This consistent temperature profile provides an almost constant tropical climate environment, with no severe cold periods to mark distinct seasons. Concurrent with this constant heat, rainfall remains a dominant feature, with average monthly precipitation spanning from a low of 168mm (6.61") to a high of 368mm (14.49").

The frequency of rainy days throughout the year slightly fluctuates, with a minimum of 12 days in the middle of the year and reaching a crest of 20 days as the year ends. Providing the area with ample daylight, the sun appears for about 12 to 12.3 hours daily, with sunshine hours varying from 4.2 hours to 6.4 hours. This combination of abundant rain, high temperatures and adequate sunshine underscores the tropical rainforest climate of Sibu.

Sparing visitors from the constant rainfall that embodies Sibu's climate is the period from June to July. Despite being the driest months of the year, this period still witnesses an average of 193mm (7.6") to 168mm (6.61") of rainfall spread over about 12 rainy days. Coupled with consistently high temperatures of around 32.7°C (90.9°F) and extended sunshine hours reaching up to 6.4 hours per day, this time offers a relatively less humid climate for exploration and outdoor activity.

In contrast to the driest period, the months from December to January stand as the wettest throughout the year - showcasing a marked increase in rainfall, from 360mm (14.17") to 368mm (14.49"), spanning over 19 to 20 days. These increased rain episodes, coupled with slightly lower temperatures, could hamper outdoor activities and travel plans, making it less favorable for visitors.

In the tropical climate of Sibu, the concept of traditional spring does not apply. However, moving along the months, March to May demonstrate average temperature highs ranging from 32°C (89.6°F) to 33°C (91.4°F) and lows between 22.8°C (73°F) to 23.1°C (73.6°F). On average, a rainfall of 228mm (8.98") to 301mm (11.85") occurs across 15 to 17 rainy days, while daylight lasts for 12.1 to 12.2 hours with about 4.9 to 6.2 hours of sunshine.

June to August, normally considered as summer months in other regions, see a slight drop in rainfall in this part of Malaysia. The volume of rain falls between 168mm (6.61") to 218mm (8.58"), happening over 12 to 14 days. Enveloped in the tropical atmosphere, temperatures remain constant, moving from highs of 32.7°C (90.9°F) to around 32.6°C (90.7°F) and lows varying narrowly from 22.5°C (72.5°F) to 22.6°C (72.7°F). Hours of sunshine show an increase, touching up to 6.4 hours on longer days of 12.3 hours in June.

September through November, the months generally regarded as autumn in temperate regions, see a rise in rainfall again, with figures ranging from 276mm (10.87") to 295mm (11.61") over 16 to 19 days. Despite the rising rain episodes, temperatures largely remain constant with highs of 32.2°C (90°F) to 31.9°C (89.4°F) and lows around 22.7°C (72.9°F). Daily sunshine hours still remain substantial, from 5.4 hours on 12.1 hours long days.

There is no concept of a traditional winter season in Sibu's tropical climate. However, December marks the beginning of the wettest period in the year with an average rainfall of 360mm (14.17") over 20 days. The average high temperature drops slightly to 30.3°C (86.5°F) and the low reaching 22.8°C (73°F). This period is characterized by shorter sunshine durations of around 4.8 hours in 12-hour long days, further underscoring the propensity for indoor activities during this time.

January remains in the wettest quarter of the year in Sibu, characterized by significant rainfall encompassing 19 days on average. Comparatively, the subsequent month of February experiences a reduction of rainfall while cooler temperatures follow in March. Weather in January »

Transitioning from January, the weather in February sees a relative respite from raining days dropping to 15. Expect temperatures to become slightly warmer than the preceding month, though the difference isn’t too large. February is the month with the lowest amount of rainfall - 258mm (10.16"). Weather in February »

The month of March subtly initiates the transition toward the dry period in Sibu. The onset of warmer weather in comparison to February starts to become evident. An average temperature rise from 31.2°C (88.2°F) in February to 32°C (89.6°F) in March characterizes this trend. Weather in March »

The monthly highs continue to rise in April, a trend started by March. Equatorial equinox observed during this period culminates in the most extended daylight hours, an increase from 12.1 hours earlier. Despite a rise in temperature to 32.8°C (91°F), there is only a tiny increase in rainfall from the preceding month. Weather in April »

With high temperatures remaining steady, May in Sibu, Malaysia, marks the beginning of mildly cooler nights. The contrast with April is small, yet it marks the start of a consistent decrease in rainfall. The levels of UV radiation continue to be remarkably high during this sunnier period, indicating a need for sun protection. Weather in May »

June falls within the hot and dry period, which is synonymous with Sibu's equatorial climate. It is marked by a slight decrease in rainfall from May and a slight tinge of cooler temperatures at night. Temperatures remain high, even hovering around 32.8°C (91°F) during the day. Weather in June »

Subtle changes in Sibu weather continue in July. July's highlight is the decrease in average daily high temperatures, dipping under 32.7°C (90.9°F). The mild change in daylight hours and temperatures between June and July goes unseen to the untrained eye. Weather in July »

Notably, August's weather features slightly cooler nights compared to the preceding month of July. The increase in rainfall and intensity of UV radiation is not noteworthy, but it will affect outdoor activities. A slight increase in temperatures from 32.7°C (90.9°F) to 32.6°C (90.7°F) is observed from July to August. Weather in August »

A shift towards increased rainfall happens in September, setting grounds for the stormy quarter of the year. Gradual warming indicates an annual pattern of rising temperatures, which normally extends into the subsequent month of October. Weather in September »

October brings along a wee bit of warmth compared to September. This begins a trend noticeable in the succeeding months of November and December. From 32.2°C (90°F) in September, the temperatures rise to a high of 32.1°C (89.8°F) in October. Weather in October »

November follows the warming trend noted in the past few months, leading to the warmest period of the year. Rainfall tends to increase, given the approach of the wettest month of the year - December. The temperatures range close to 31.9°C (89.4°F) during the day, indicating a mild cooling effect from October. Weather in November »

December usually ends up as the month with the most rain in Sibu, lending a moist tinge to the closing of the year. A rising trend in precipitation is evident, which has been building up since October. A significant increase in rainfall to 360mm (14.17") is observed from November to December. Weather in December »