Track rain and storms across Nakhon Sawan and the upper Chao Phraya basin. Updates every 5 minutes.
Nakhon Sawan lies at the meeting point of the Ping, Wang, Yom, and Nan rivers — the source of the Chao Phraya, Thailand’s most significant waterway. This strategic position means rainfall here has a direct impact on water levels downstream towards Bangkok. The city serves as a vital flood monitoring location for the entire Central Plains.
Monsoon rains combine with runoff from the four main rivers. September–October are the most critical months for flooding — the 2011 floods that devastated Bangkok began in this watershed. Monthly rainfall averages 200–250 mm during the peak months.
In November, river levels gradually recede. April brings dry heat exceeding 40°C, with occasional pre-monsoon storms offering brief respite.
Rainfall falls below 15 mm per month. Water management in the Bhumibol and Sirikit dams becomes crucial, as reservoir levels determine dry-season water allocation for agriculture and cities further downstream.
One tap, and the rain at that precise spot tells its own story—showing intensity, precipitation type, cloud and air temperatures, and live national alerts, while making even the smallest rain pockets easy to identify and compare.
The Royal Irrigation Department monitors rainfall in the Nakhon Sawan watershed to coordinate dam releases and flood prevention for the entire Chao Phraya basin.
The surrounding plains are among Thailand's most productive rice-growing areas. Farmers time planting and harvesting around monsoon patterns tracked via radar.
Bung Boraphet, Thailand's largest freshwater lake, supports a significant fishing industry. Storm tracking helps fishermen on the lake stay safe.
Nakhon Sawan is a major highway junction connecting northern and central Thailand. Flood monitoring along Highway 1 and Highway 117 is essential during monsoon season.
Rain Viewer covers the whole of Nakhon Sawan province and the surrounding river basins. Coverage extends north towards Phitsanulok, east to Phetchabun, and south along the Chao Phraya towards Chai Nat and Singburi. The relatively flat terrain provides excellent radar propagation.
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The four main rivers converge here to form the Chao Phraya. Heavy rainfall in this catchment area flows downstream to Bangkok within days, making upstream radar monitoring essential for flood forecasting.
Yes. Prolonged heavy rainfall visible on radar over the Ping, Wang, Yom, and Nan river basins north of Nakhon Sawan signals rising water levels at the confluence, usually 12–24 hours later.
Farmers monitor radar to protect drying rice from unexpected rain and to schedule irrigation when natural rainfall is insufficient during dry spells in the monsoon season.
Nakhon Sawan’s rainfall feeds the entire Chao Phraya system, but what matters locally is the next two hours — not the season. The map updates every 5 minutes — often 2–5 minutes faster than other apps — so by the time a cell is building over the Ping valley upstream, you’ve already seen it heading towards the confluence.
Rain Viewer Essential gives you:
A 7-day forecast tells you October will be wet. Rain Viewer tells you whether the afternoon is clear enough to send in the cutting crew or wait until tomorrow.
Track rain in Nakhon Sawan — free
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