- 🌡️ Heatwave risk HIGH · consecutive days >35°C expected May · heat index 42–45°C · crop ET demand +15–20% before monsoon arrives
- 📅 Monsoon onset · Computing MJO-adjusted estimate…
- 🌊 Flood risk LOW–MOD now, rising Jul–Aug · low-lying paddy fields in Chao Phraya and Isan watch from mid-July · flash flood risk on Khorat slopes if MJO Phase 3–4 triggers convective burst
- 🌾 Crop stress MODERATE for Isan · cassava transplant window stresses under 28th-percentile root-zone moisture · rice seedbed establishment at risk without supplemental irrigation · mulching + drought-tolerant varieties recommended
- 💧 Reservoir buffer thin · Bhumipol 46% · Sirikit 72% · coordinate irrigation allocation with RID before planting commitments
- ⚠️ Watch Jul–Aug · El Niño development risk 60% · below-normal risk increases to 75–80% of normal if EN develops; simultaneously raises late-season flood risk in wet La Niña areas
For rice farmers in the Central Plains, the recommended posture is to hold transplanting until monsoon onset is confirmed — targeting late June rather than the usual early June window. Drought-tolerant varieties (RD47, RD51 for rainfed areas; managed KDML105 for irrigated) should be prioritised. Water allocation from Bhumipol and Sirikit will be tight; coordinate with district irrigation offices before committing to large planted areas.
Cassava growers on the Khorat Plateau face a drier-than-normal soil profile at planting time. GRACE satellite data confirms root-zone moisture at the 28th percentile — well below what supports stress-free establishment. Mulching, row orientation to shade soil, and delayed planting by 2–3 weeks where possible will reduce transplant mortality. Yield impact from early-season deficit in cassava is typically front-loaded: once canopy closes, the crop is resilient.
For supply chains and exporters, a below-normal early season raises quality risk for fresh produce and increases irrigation cost for export-grade crops. The FAO early warning status for Thailand is Monitor. The most critical decision window is the 15th–20th of each month, when updated forecasts from all agencies are published simultaneously.
