Weather Siem Reap Today – Temperature, Rain & Hourly Forecast

Today in Siem Reap runs between 25 and 30°C, with thunderstorm.

Heavy rain around 00:00–00:00, up to 24.9 mm — avoid travel at that hour if you can.

Thunderstorms are possible around 00:00–00:00.

Maximum UV of 7.2 at 12:00 — wear a hat for longer stints outdoors.

Humidity of 91% pushes the felt temperature to 31°C.

Wind runs 9 km/h out of the north-west.

Temperatures ease off, bottoming out at 24°C on Wednesday 23/09.

The wettest day ahead is Friday 25/09 with about 50 mm.

Sunrise 05:53, sunset 18:01.

Siem Reap is roughly 15% drier than Phnom Penh over the year but has a wider day-night temperature range because it sits further from the sea. For Angkor visitors, November to February is the window: dawn can drop to 18–20°C, cool enough to walk the temple complex for hours. In April the sandstone surface temperature can exceed 45°C at midday, which is why most itineraries split into an early-morning and a late-afternoon session.

— Ban biên tập KhmerMeteo · Meteorological data editors

This measures upstream rainfall, not river level. Official levels and discharge come from the Mekong River Commission (MRC). Upstream rainfall causes the level, and is visible several days earlier. MRC

This measures upstream rainfall, not river level. Official levels and discharge come from the Mekong River Commission (MRC). Upstream rainfall causes the level, and is visible several days earlier. MRC

The Mekong now stands higher than the lake, so the Tonlé Sap river runs backwards and pumps water in. Fish move upstream into the lake to spawn. This is when the lake expands fastest.

Mekong basin rainfall: 39 mm over the past 72 hours, 30 mm forecast for the next 72.

This is a seasonal estimate combined with basin rainfall, not a measured level. Official water level and discharge come from the Mekong River Commission (MRC). The timing of the reversal varies year to year and has shifted noticeably over the past two decades.