El Nino Watch
One paragraph: the level, the El Nino state, the local numbers with dates, what is on watch, and the next seasonal risk.
Koh Samui watch
Built from the factors, in this order: level and El Nino state ('Prepare -- strong El Nino (ONI +1.80 °C JJA 2026; RONI +1.36 °C; Nino 3.4 +3.0 °C week of 16 Sep)'); the local picture ('No immediate threat on Samui: rain 103% of normal (90 d to 18 Sep), waves max 0.5 m (forecast to Sat 26 Sep), no cyclone within 800 km (nearest 2,002 km)'); factors at Watch or Prepare; missing data; and the next risk of the season ('NE-monsoon heavy rain and rough seas Oct-Dec 2026; water stress Feb-Apr 2027'). `headline_local` is the same text without the first sentence (reused by the briefing).
Limits. The headline summarises; each factor card holds the full explanation and sources.
'No immediate threat' is only written when every critical factor has current data and none is at Act or Leave. Otherwise the headline names the hazards or the missing data and where to check by hand.
The El Nino 'Prepare' is about the 2027 dry season; the local numbers say whether anything threatens the island this week.