El Nino Watch

JTWC tropical cyclone warnings

US Joint Typhoon Warning Center warnings for the NW Pacific and North Indian Ocean, plus its daily advisory of developing disturbances.

Hazards

JTWC issues a warning every 6 hours for each tropical cyclone: position, 1-minute sustained winds and gusts, and a 5-day forecast track. Its Significant Tropical Weather Advisory also lists disturbances that could develop, west to the Malay Peninsula.

Limits. A military forecast centre, not Thailand's official warning service: the TMD's warnings are the official ones for Thailand. JTWC winds (1-minute) are higher than JMA's (10-minute) for the same storm.

How to read it

Same map severity as the JMA storms (red within 300 km, orange within 800 km). 'Final warning' means the storm is dissipating or has moved out; it is shown in green. Winds are in knots.

Why it matters for Koh Samui

JTWC covers the Bay of Bengal and Andaman Sea as well as the South China Sea, and its advisory often flags a Gulf of Thailand disturbance before it gets a name.

Sources

ENSO status now

ONI (NOAA CPC)
+1.80 °C, JJA 2026 (previous +1.39 °C)
RONI (NOAA CPC)
+1.36 °C, JJA 2026
Nino 3.4 weekly (NOAA CPC / OISST)
+3.0 °C anomaly, week of 16 Sep 2026 (SST 29.6 °C)