Cambodia weather in May

Cambodia weather in May – first showers of the wet season

Early–mid May stays mostly dry and very warm; by late month the first short showers arrive as the wet season approaches. Heat eases slightly when rains break the humidity, and crowds thin at the big-name temples. Expect bright mornings, hot middays and the odd late-day downpour — great conditions if you plan early starts and long lunch breaks.

May Quick Facts — Cambodia
• Siem Reap: ~26–35 °C; brief late-day showers possible, especially late month.
• Phnom Penh: ~27–35 °C; hot, humid afternoons; first storms break the heat.
• South coast & islands (Sihanoukville/Koh Rong): sea ~29–30 °C; more frequent but short showers.
Based on multi-year climate normals for May.

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1. May Weather Overview (What to Expect)

May straddles the end of the dry season and the start of the rains. Sunshine dominates many mornings; convection clouds can build by late afternoon, bringing short, heavy showers or a thunderstorm — most last 30–60 minutes.

Rainfall: low to moderate and unevenly distributed; more frequent toward month’s end and along the south coast.
Temperatures: afternoons commonly 33–35 °C on the plains; nights around 26–27 °C. Highlands run a few degrees cooler.
Humidity: rising; showers help take the edge off the heat.
Beach & Sea: sea stays warm ~29–30 °C; expect the odd passing shower and slightly choppier days.
Comfort level: best at dawn and after 16:00; plan shade or indoor time around noon–15:00.

May Climate Snapshot by Region

Region / Base	Average High (°C)	Average Low (°C)	Rainfall (mm)	Rain Days	Humidity (%)	Sea Temp (°C)
Siem Reap (Angkor)	35	26	~100–150	5–8	65–70	—
Phnom Penh (Capital)	35	27	~120–160	6–9	65–70	—
Sihanoukville / Kep / Kampot	32–33	27	~200–260	8–12	70–75	29–30
Mondulkiri / Ratanakiri (Highlands)	31–33	22–24	~140–200	8–12	65–70	—

2. Where to Go in May (Best-Fit by Traveller Type)

May rewards early risers and those who like fewer crowds. Use this quick selector to match your style to the right region:

Traveller Profile	Go Here	Why in May	Top Experiences
First-timers & culture lovers	Siem Reap (Angkor)	Quieter temples; bright mornings; short late-day showers	Angkor sunrise, Ta Prohm shade, Bayon bas-reliefs
City & food	Phnom Penh	Museums/cafés for peak heat; breezier evenings by the river	Royal Palace, National Museum, craft coffee & street-food
Beach & snorkeling	Kep, Kampot & islands off Sihanoukville	Warm water ~29–30 °C; showers usually short and passing	Kep crab market, Kampot pepper farms, Koh Rong/Koh Rong Samloem
Cooler mornings & soft adventure	Mondulkiri & Ratanakiri	Highlands are cooler at dawn; lush scenery begins to return	Observe-and-walk elephant programs, hill-tribe villages

Siem Reap & Angkor

Beat the heat with a pre-dawn start at Angkor Wat, rotate shaded interiors (Bayon/Angkor Thom) into late morning, then break for lunch/pool time. If showers roll in late day, they often clear for a golden-hour circuit.

Phnom Penh

Plan air-conditioned museum time around noon; riverside walks on Sisowath Quay feel best after 16:00. Keep a light rain layer for pop-up storms.

Kep, Kampot & the Islands

Seas remain warm and inviting (~29–30 °C). Showers are usually brief; boats to Koh Rong or Koh Rong Samloem run most days, with occasional weather holds.

Mondulkiri & Ratanakiri

Dawn temperatures are gentler than the plains. Early wet-season greens start returning — great for short hikes and softer landscapes. Choose ethical, no-riding elephant experiences.

Slash & Burn

Traveling in April–May, you may notice “slash & burn” agricultural practices in rural areas. Fires used to clear fields can create a light haze, especially outside major cities. It rarely disrupts travel, but visibility can soften and afternoons may feel stuffier.

3. Events & Festive Notes in May

King Norodom Sihamoni’s Birthday — 14 May (public holiday). Expect busier domestic travel and some government/office closures.
Royal Ploughing Ceremony (Bonn Chroat Preah Nongkoal) — date varies (often May). A traditional omen-reading ceremony marking the farming season; locations and timings vary year to year.
Coast & islands: sunset boats and barbecues continue; occasional showers are typically short.

4. Practical Tips for May Travellers

Heat & rain strategy: plan outdoors 06:00–10:00 & 16:00–18:30; keep a light rain layer for pop-up storms.
Packing list: breathable fabrics, sun hat, reef-safe sunscreen, sunglasses, quick-dry shoes/sandals, compact umbrella.
Temple etiquette: shoulders and knees covered; a light scarf or cover-up helps.
Transport buffers: allow a little extra time for flights/boats if afternoon storms are forecast.
Hydration: refillable bottle; electrolytes recommended for hot days.

5. Frequently Asked Questions (May, Cambodia)

Is May a good month to visit Cambodia?

Yes — if you like fewer crowds and don’t mind short showers. Mornings are bright, and rains usually arrive late day and pass quickly.

Is it very rainy in May?

Not usually. Early–mid May is often mostly dry; by late month you’ll see more short, heavy showers, especially on the coast.

How hot is Siem Reap in May?

Around 26–35 °C across the day. It feels hottest at midday; plan early starts and a long lunch break.

What is the sea temperature in May?

About 29–30 °C along the south coast and around the islands — ideal for swimming and snorkeling.

Where should I go in May?

For culture, Siem Reap (Angkor) with early starts. For beaches, Kep, Kampot and the islands off Sihanoukville. For cooler dawns and emerging greenery, head to Mondulkiri or Ratanakiri.