The short version: Malaysia is warm and humid every single day of the year, and it rains all year too. There is no dry season. What actually changes is where the rain falls and how rough the sea gets, and that difference between the two coasts is the only thing on this page that will genuinely affect your trip.
If you are here about December specifically, the answer is: fine on the west coast, bad on the east. The full explanation is below.
Temperature barely changes, so stop planning around it
Lowland Malaysia sits at roughly 26 to 32 degrees during the day, all year, dropping to about 23 or 24 overnight. December is marginally the coolest month in Kuala Lumpur and the difference against the hottest month is a couple of degrees, which you will not notice against the humidity.
This is genuinely useful to know, because it means there is no month that is too hot or too cold to visit. Anyone telling you to avoid Malaysia because of temperature is padding an article. The only place with a meaningfully different climate is the highlands, and Cameron Highlands runs around 14 to 24 degrees, which is why Malaysians go there to escape the heat.
What varies is rain. That is the whole story.
The two monsoons, explained simply
Malaysia’s year runs in four phases, and knowing which one you are arriving in tells you more than any monthly average.
- Northeast monsoon, roughly November to March. Hits the east coast hard. This is the one that closes islands.
- First inter-monsoon, roughly March to May. Transitional, with thunderstorms.
- Southwest monsoon, roughly May to September. Milder, and affects the west coast far less dramatically.
- Second inter-monsoon, roughly October to November. Transitional again, and often the wettest stretch in Kuala Lumpur.
Here is the counterintuitive part. In Kuala Lumpur, the wettest periods are not the monsoons. They are the two inter-monsoon transitions, March to April and October to November. Most visitors assume “monsoon season” means the rainiest time for the capital, and for KL that is simply not how it works.
Why the two coasts are completely different
This is the single most important thing to understand about Malaysian weather, and it is the reason generic month-by-month guides mislead people.
The west coast, which includes Kuala Lumpur, Penang, Langkawi, Melaka and Pangkor, is sheltered by the island of Sumatra sitting across the strait. That creates a rain-shadow effect during the northeast monsoon, so while the east is being battered, the west stays relatively calm and sunny.
The east coast, which includes Tioman, Redang, the Perhentians, Kuantan and Kota Bharu, takes the northeast monsoon directly. November and December there can exceed 400 to 500 mm of rain in a month, several times what the west receives. Seas turn rough, ferries stop and most island resorts close entirely.
So “what is the weather like in Malaysia in December” has two correct and opposite answers depending on which side of a fairly narrow peninsula you are standing on.
| Period | West coast and KL | East coast and islands |
|---|---|---|
| November to February | Drier, good | Monsoon, islands closed |
| March to May | Wetter, frequent storms | Reopening, improving |
| June to September | Reasonably dry | Best conditions |
| October to November | Wettest stretch in KL | Closing down |
Month by month, honestly
A note on why this table has no precise millimetre figures. In Malaysia the year-to-year variation for any given month is larger than the difference between neighbouring months. A table claiming April gets 280 mm and May gets 220 mm implies a precision that does not survive contact with an actual wet April. The bands below are more honest and will serve you better.
| Month | KL and west coast | East coast | Verdict |
|---|---|---|---|
| January | Drier | Monsoon, closed | Good for KL, Penang, Langkawi |
| February | Driest stretch | Monsoon, closed | One of the best months west |
| March | Wetter, storms building | Reopening | Transitional |
| April | Wet, frequent storms | Good, improving | East coast becomes the better bet |
| May | Wet | Good | Go east |
| June | Drier | Very good | Strong all round |
| July | Drier | Very good | Strong all round |
| August | Moderate, haze risk | Very good | Good, watch air quality |
| September | Wetter, haze risk | Good | Mixed |
| October | Wettest stretch | Deteriorating | Weakest month overall |
| November | Wettest stretch | Monsoon begins, closing | Weak |
| December | Drier, improving | Peak monsoon, closed | Good west, avoid east |
December in detail, since that is what most people ask
In Kuala Lumpur, December daytime highs sit around 31 to 32 degrees with nights near 23. Expect something in the region of 230 to 250 mm of rain across the month, spread over roughly 20 days, and about 5 to 6 hours of sunshine a day. Those figures vary between sources, so treat them as the general shape rather than a forecast.
Twenty rain days out of thirty-one sounds alarming and is not, because of how the rain arrives. In KL it usually comes as a heavy afternoon or evening thunderstorm lasting perhaps an hour, then clearing. You are rarely rained off for a whole day. Our guide to the KL rainy season goes into that pattern properly.
December is also peak travel season. School holidays, Christmas and New Year mean higher hotel rates, busier attractions and packed domestic transport. Weather is not the constraint in December; other travellers are.
If you are picturing a beach holiday in December, go west. Langkawi and Penang are at their most reliable. The east coast islands are shut. Our guide to beaches and islands reachable from KL covers which are open when.
The haze, which most guides skip
Around August and September, smoke from agricultural fires in Sumatra and sometimes Kalimantan can drift across the strait and settle over the Klang Valley. In a bad year the skyline disappears, air quality readings climb into unhealthy territory and people with asthma have a genuinely unpleasant time.
It does not happen every year and severity varies a lot. But it is a real seasonal risk that tourism material tends not to mention, and if you have a respiratory condition it is worth knowing before you book late-August dates. Check current air quality readings close to your travel date rather than assuming.
What this means for planning
- City trip to KL: any month works. Rain is short and the city is built for it. Pick your dates on price and crowds instead.
- West coast beaches: November to February is the sweet spot, especially January and February.
- East coast islands: April to September, and nothing outside March to October.
- Trying to do both coasts: aim for the March to April or September to October shoulders and accept a compromise.
- Diving: April to September on the east coast, when visibility is best.
- Avoiding crowds: skip December and major school holidays.
For Kuala Lumpur specifically, including festivals and events that matter more than weather when picking dates, see our guide to the best time to visit Kuala Lumpur.
What to pack, briefly
The same things in every month, which is one advantage of a climate this consistent. Light breathable clothing, something with sleeves for mosques and temples, a compact umbrella or light rain layer, and a warm layer for the aggressive indoor air conditioning, which catches more visitors out than the rain does. Our KL packing guide has the full list.
If a storm does trap you, it is not a lost afternoon. Our list of things to do in KL when it rains covers the indoor options.
Official & useful resources
Frequently asked questions
What is the weather like in Malaysia in December?
Warm and humid everywhere, roughly 23 to 32 degrees, but the two coasts differ sharply. The east coast is in the northeast monsoon with heavy rain, rough seas and island resorts closed. The west coast, including Kuala Lumpur, Penang and Langkawi, is much drier and is one of the better times to visit those areas.
Does Malaysia have a dry season?
No. It rains year round across the whole country. What changes is which coast is getting the heaviest rain and how rough the sea is. Any guide promising a dry season is oversimplifying a tropical climate.
What is the rainiest month in Kuala Lumpur?
The wettest stretch is usually October to November, during the second inter-monsoon, with a secondary peak in March and April. Counterintuitively, the northeast monsoon months are not the wettest for KL, because the west coast is sheltered by Sumatra.
Is it always hot in Malaysia?
In the lowlands, yes. Expect roughly 26 to 32 degrees by day and about 23 to 24 at night, almost every day of the year, with high humidity throughout. The exception is the highlands, where Cameron Highlands sits around 14 to 24 degrees.
Which month is best to visit Malaysia?
June and July are the strongest all-round months, with reasonable conditions on both coasts. For the west coast alone, January and February are excellent. For east coast islands and diving, April to September. October and November are the weakest overall.
When does the haze affect Malaysia?
Typically August and September, when smoke from agricultural fires in Indonesia can drift over the peninsula. It does not occur every year and severity varies. If you have a respiratory condition, check current air pollutant index readings before travelling in those months.
Related reading
- Best time to visit Kuala Lumpur, festivals, crowds and prices
- KL in the rainy season, is it a dealbreaker
- Things to do in KL when it rains
- What to pack for Kuala Lumpur
- The Kuala Lumpur travel guide
