Rainfall in Nagaon
Nagaon gets 63% of its rain from the monsoon, June to September, and June is its wettest month. In 2025 it got 1,330 mm, 14% below average (normal).
Month-wise rainfall in Nagaon
Average rain in each month, 2006–2025.
| Month | Average rain | Share of the year |
|---|---|---|
| January | 8 mm | 1% |
| February | 20 mm | 1% |
| March | 47 mm | 3% |
| April | 152 mm | 10% |
| May | 237 mm | 15% |
| June | 309 mm | 20% |
| July | 271 mm | 17% |
| August | 215 mm | 14% |
| September | 184 mm | 12% |
| October | 91 mm | 6% |
| November | 15 mm | 1% |
| December | 8 mm | 1% |
Yearly rainfall in Nagaon since 2006
Lighter bars are dry years, 20% or more below average (2006, 2021, 2023), when wells and borewells are drawn hardest. The last ten years averaged 9% less rain than the ten before.
What Nagaon's rain is worth to a building
Every millimetre of rain on a square metre of roof is a litre of water. A 100 m² roof in Nagaon sheds about 1,32,175 litres in an average year, most of it in four monsoon months. Sent into a recharge pit, it refills the ground instead of flooding the street.
Your building: how much can you recharge?
1 mm of rain on 1 m² is 1 litre. The surface factor allows for water lost to splash, evaporation and first-flush.
Frequently asked questions
What is the average annual rainfall in Nagaon?
About 1,555 mm a year, averaged over 2006–2025 from NASA POWER satellite and weather-model data for the centre of the district. The wettest year in that time was 2010 (1,980 mm) and the driest was 2023 (1,154 mm).
Which month gets the most rain in Nagaon?
June, with 309 mm in an average year, followed by July and May. January is the driest month (8 mm).
How much of Nagaon's rain falls in the monsoon?
63% of a normal year's rain falls from June to September. 7 months average 50 mm or more.
How much did it rain in Nagaon in 2025?
1,330 mm, which is 14% below the 2006–2025 average, or "normal" in the India Meteorological Department's terms.
Is rainfall in Nagaon increasing or decreasing?
The last 10 years averaged 9% less rain than the 10 before them. Year-to-year swings are still bigger than that change.
How much rainwater can a house in Nagaon harvest?
A 100 m² (about 1,076 sq ft) concrete roof in Nagaon sheds about 1,32,175 litres in an average year: area × rainfall × 0.85 for splash and evaporation. Sent into a recharge pit, that refills the ground under the house instead of running into the drain.
Rainfall from NASA POWER (bias-corrected satellite and weather-model rainfall) at the centre of Nagaon district. It reads close to, but not exactly the same as, India Meteorological Department rain-gauge totals, and rain varies within a district.