GISTDA expects heavy rain across Thailand to ease from September 28
GISTDA expects Thailand’s heavy rain risk to ease from September 28 as atmospheric moisture declines, though scattered rain will persist in several regions.
- Thailand's heavy rain is forecast to ease from September 28, according to the nation's space agency, GISTDA.
- The period of greatest concern for heavy downpours was identified as September 26-27, particularly in the Central and Eastern regions.
- The prediction is based on data showing that atmospheric moisture, a key factor in heavy rain, is expected to weaken significantly from September 28.
- Despite the improving conditions, residents were advised to remain alert as scattered rainfall may continue in several areas after this date.
Thailand’s heavy rain is expected to begin easing from September 28 after the period of greatest concern on September 26-27, particularly in the Central and Eastern regions, according to the Geo-Informatics and Space Technology Development Agency (GISTDA).
GISTDA is tracking atmospheric moisture using Integrated Vapor Transport (IVT) data alongside satellite information, geo-informatics technology and weather forecasting models. The data help identify the direction and concentration of moisture moving from the sea towards land, one of the factors used to assess areas at risk of heavy rain and flash flooding.
On Sunday (September 27), moisture transport is expected to weaken but remain at levels 2-3 over the upper South, the upper Gulf of Thailand and parts of the East. Overall rainfall should begin to decline, although the Central and Eastern regions could still receive heavy rain of about 35-90 millimetres per day.
Atmospheric moisture to weaken from September 28
Conditions are expected to improve from September 28, with IVT readings across most areas falling to levels 1-2, indicating weak to moderate moisture transport.
Some atmospheric moisture is expected to remain over the Andaman Sea, the upper South and the upper Gulf of Thailand, while IVT readings could still reach level 3 in some areas.
By September 29-30, moisture levels across the country are forecast to fall to levels 1-2, significantly reducing the risk of heavy rain.
Scattered rainfall is nevertheless expected to continue in several areas, particularly the lower North, the West, the upper Northeast and the East.
Central and eastern areas urged to remain alert
GISTDA advised people in risk-prone areas, particularly in the Central and Eastern regions, to closely monitor heavy rain and accumulated rainfall on September 26-27.
Areas with high levels of accumulated rainfall could face flash flooding or run-off.
From September 28-30, both atmospheric moisture and rainfall intensity are expected to decline, indicating that heavy rain will gradually ease. People are still advised to continue monitoring local weather conditions and official warnings.
