Heavy rain expected in 32 provinces with 70% of Bangkok affected

Today’s weather forecast from the Meteorological Department of Thailand (TMD) predicts heavy rain across 32 provinces, with Bangkok expected to experience downpours over 70% of its area. Citizens are advised to stay alert for potential flash floods and forest runoff.

The TMD issued a weather forecast for the next 24 hours, predicting thunderstorms and heavy rainfall in central, eastern, and southern Thailand. Residents in these regions are urged to be cautious of heavy rain and accumulated rainfall, which could lead to sudden flooding and forest runoff, particularly in mountain slopes near waterways and low-lying areas.

The high-pressure system or cold air mass from China covering the upper northern and upper northeastern regions of Thailand is causing this weather pattern. This results in easterly and southeasterly winds bringing moisture from the South China Sea and the Gulf of Thailand to cover the lower northern, lower northeastern, central, and eastern regions.

Along with the monsoon trough passing through the upper Gulf of Thailand, the eastern and upper southern regions are also affected. In the Andaman Sea and the Gulf of Thailand, moderate waves are expected. The Andaman Sea will see waves between one to two metres, while the Gulf of Thailand will have waves about 1 metre high and more than 2 metres in areas with thunderstorms.

Mariners in these regions are advised to proceed with caution and avoid sailing in areas with thunderstorms.

In the northern region, there will be thunderstorms covering 60% of the area, mostly in Mae Hong Son, Tak, Kamphaeng Phet, Sukhothai, Phichit, and Phetchabun provinces. Temperatures will range from a minimum of 21 to 24 degrees Celcius (°C) to a maximum of 32 to 34°C. Easterly winds will blow at a speed of 10 to 15 kilometres per hour (km/h).

Regional updates

In the northeastern region, thunderstorms are expected in 60% of the area, primarily in Loei, Chaiyaphum, Nakhon Ratchasima, Buriram, Surin, Sisaket, Khon Kaen, and Nong Bua Lam Phu provinces. The temperature will range from 22 to 25°C at the lowest to 32 to 33°C at the highest, with easterly winds blowing at 10 to 20 km/h.

In the central region, 70% of the area will experience thunderstorms with heavy rain in some places, particularly in Kanchanaburi, Ratchaburi, Phra Nakhon Si Ayutthaya, Nakhon Pathom, Samut Sakhon, and Samut Songkhram provinces. Temperatures will range from 23 to 25°C at the lowest to 31 to 34°C at the highest, with easterly winds blowing at 10 to 20 km/h.

In the eastern region, 70% of the area will have thunderstorms with heavy rain in some places, especially in Nakhon Nayok, Prachin Buri, Chachoengsao, Chon Buri, Rayong, Chanthaburi, and Trat provinces. The temperature will range from 23 to 25°C at the lowest to 32 to 34°C at the highest, with variable winds blowing at 15 to 30 km/h. The sea will have waves about 1 metre high, and more than 2 metres high in areas with thunderstorms.

In the southern region (eastern coast), 40% of the area will have thunderstorms with heavy rain in some places, particularly in Phetchaburi and Prachuap Khiri Khan provinces. Temperatures will range from 23 to 25°C at the lowest to 30 to 35°C at the highest, with variable winds blowing at 15 to 30 km/h. The sea will have waves about 1 metre high, and more than 2 metres high in areas with thunderstorms.

In the southern region (western coast), 30% of the area will have thunderstorms, mostly in Ranong and Phang Nga provinces. Temperatures will range from 23 to 25°C at the lowest to 31 to 35°C at the highest, with southwesterly winds blowing at 15 to 35 km/h in areas from Phuket upwards and 15 to 30 km/h from Krabi downwards. The sea will have waves between 1 to 2 metres high, and more than 2 metres high in areas with thunderstorms.

In Bangkok and its vicinity, 70% of the area will see thunderstorms with heavy rain in some places. Temperatures will range from 25 to 26°C at the lowest to 32 to 34°C at the highest, with easterly winds blowing at 10 to 20 km/h.