Newest Himawari and GOES satellite images: infrared works day and night, true colour only by day.
Ocean
The newest images from geostationary weather satellites 36,000 km above the equator: - Himawari-9 (Japan Meteorological Agency) at 140.7 E: the full Earth disk and a Southeast Asia sector covering Thailand and the Gulf of Thailand. New image every 10 minutes. - GOES-West (GOES-18) over the central / eastern Pacific, where the Nino 3.4 region lies, and GOES-East (GOES-19) over the Americas (Peru / Ecuador).
Limits.
Pixels are 2-4 km: a single storm cell over Samui is a dot.
Bright cloud does not always rain; thin high cirrus looks bright in infrared too.
The image is 10-40 min old when you see it (scan + publish + our check interval).
For rain now, use the radar layer; for forecasts, the local risk page.
How to read it
Infrared (Himawari B13, GOES band 13): brightness = cold. Bright white blobs are tall, cold thunderstorm tops (heavy rain); grey is low cloud; dark is clear sky or warm sea. Works day and night.
True colour (Himawari "True Color Reproduction"): what your eye would see; cloud is white, haze and smoke are milky brown-grey. Black at night.
GeoColor (GOES): true colour in daylight, infrared clouds plus city lights at night.
A spiral of bright white cloud with a clear centre is a tropical cyclone.
The time shown is UTC (Koh Samui = UTC + 7).
Why it matters for Koh Samui
El Nino moves the Pacific's big thunderstorm clusters east, away from Indonesia and toward the central Pacific: fewer bright white clusters over the Maritime Continent, more near the date line. On the Southeast Asia sector you can watch storms and squall lines approach the Gulf of Thailand and smoke haze in dry spells.