Monsoon surge brings 70% rainfall to North, Northeast; Bangkok hit by thunderstorms

Bangkok will see thunderstorms, while the South faces moderate seas with waves up to two metres high.

Nationwide forecast: Monsoon surge causes widespread storms

The 24-hour forecast warns of isolated heavy rain in the North, Northeast, East, and South. Residents in these regions are advised to beware of flash floods and runoffs, especially in foothill areas, near waterways, and low-lying terrain.

The unsettled conditions are due to a low-pressure cell over northern Vietnam combined with a moderate southwest monsoon prevailing over the Andaman Sea, Thailand, and the Gulf of Thailand.

Marine conditions: Moderate waves, stormy seas

Wave conditions in the upper Andaman Sea are expected to reach about 2 metres in height, while seas in the lower Andaman and upper Gulf of Thailand will see waves ranging from 1–2 metres. In areas experiencing thunderstorms, waves could exceed 2 metres. Mariners are urged to exercise caution and avoid sailing near stormy areas.

Tropical storm Danas update

Typhoon Danas, which had earlier formed near Taiwan, has weakened into a severe tropical storm and is projected to make landfall in China between July 8 and 9. The storm will not directly affect Thailand, but it will strengthen the southwest monsoon currently over the country.

Regional Forecast Highlights (valid 6am, Monday (July 7) to 6am, Tuesday (July 8)

Bangkok and surrounding provinces:

Thunderstorms covering 60% of the area

• Low: 26–27°C 
• High: 33–34°C
• Southwesterly winds at 10–20 km/h

Northern Region:

Thunderstorms in 70% of the area with isolated heavy rain in Mae Hong Son, Chiang Mai, Chiang Rai, Lampang, Phayao, Nan, Phrae, Tak, Phitsanulok, and Phetchabun

• Low: 22–26°C 
• High: 30–34°C
• Southwesterly winds at 10–20 km/h

Northeastern Region

Thunderstorms are expected in 70% of the area, with isolated heavy rain in Loei, Nong Khai, Bueng Kan, Udon Thani, Sakon Nakhon, Nakhon Phanom, Kalasin, Mukdahan, Yasothon, Amnat Charoen, and Ubon Ratchathani.

• Low: 23–25°C
• High: 31–35°C
• Southwesterly winds: 10–20 km/h

Central Region:

Thunderstorms are expected in 60% of the area, especially in Lopburi, Saraburi, Kanchanaburi, Ratchaburi, Nakhon Pathom, Samut Songkhram, and Samut Sakhon.

• Low: 23–26°C
• High: 33–35°C
• Southwesterly winds: 10–20 km/h

Eastern Region:

Thunderstorms are expected in 70% of the area, with isolated heavy rain in Nakhon Nayok, Prachin Buri, Chanthaburi, and Trat.

• Low: 25–27°C
• High: 32–34°C
• Southwesterly winds: 15–35 km/h
• Sea conditions: Waves 1–2 metres high; over 2 metres in areas with thunderstorms

Southern Region (east coast):

Thunderstorms are expected in 40% of the area, mostly in Phetchaburi, Prachuap Khiri Khan, Chumphon, and Surat Thani.

• Low: 23–25°C
• High: 34–35°C
• Southwesterly winds: 15–35 km/h
• Sea conditions: Waves around 1 metre, rising to 1–2 metres offshore; more than 2 metres in stormy areas

Southern Region (west coast):

Thunderstorms are expected in 60% of the area, with isolated heavy rain in Ranong and Phang Nga.

• Low: 24–27°C
• High: 31–34°C
• Phang Nga and northwards:
• Southwesterly winds: 20–35 km/h
• Waves around 2 metres, exceeding 2 metres during storms
• From Phuket southwards:
• Southwesterly winds: 15–35 km/h
• Waves 1–2 metres, higher than 2 metres in thunderstorm zones