Environment › Climate science
Extreme weather, monsoon and forecasting
Weather and its extremes: the monsoon and the ocean patterns that drive it, heatwaves, cyclones, cloudbursts and lightning, and the forecasts, radars and warnings that meet them. Prelims has asked about the Finance Commission's recommendations on disaster funding.
27 Aug 2026 · Prelims and Mains
Notified natural calamities
Whether a hazard is on the notified list decides how a State may pay for it, because a notified natural calamity is one for which a State may draw on its State Disaster Response Fund for relief and reconstruction.
- State Disaster Response Fund
- The fund a State draws on for relief and reconstruction immediately after a notified disaster.
- State Disaster Mitigation Fund
- The fund for long term works that reduce disaster risk before a disaster, rather than relief after one.
- Heatwaves and lightning became notified natural calamities on 27 August 2026, taking the list to 14, on a Sixteenth Finance Commission recommendation announced in the Lok Sabha on 4 August 2026.
- A hazard outside the list can be notified by a State itself as a local disaster, but funded only from a capped slice of the same money, 10 per cent of the annual allocation.
- Heat was earlier only a local disaster, so a State may now spend its full response fund on it.
- The response fund pays for relief after a disaster; the State Disaster Mitigation Fund pays for work that reduces risk before one.
- A Finance Commission is constituted under Article 280 of the Constitution and recommends how central taxes and grants are shared with the States.
- The Sixteenth Finance Commission recommended ₹2.04 lakh crore for State disaster funds for 2026-31, split between the two funds.
- An assessment cited with the notification puts over 57 per cent of districts at high to very high heat risk, and those districts are home to about three quarters of Indians.
- Disaster finance was built for sudden events such as floods and cyclones, and heat is a slow hazard.
UPSC has asked
- Prelims 2025: recommendations of the Fifteenth Finance Commission
See also: Heat Action Plans
12 Sep 2026 · 10 Sep 2026 · Prelims and Mains
Bihar's Ganga floods
The river stood at or above its highest recorded level at Patna and Bhagalpur in September 2026 while the State's rain since 1 June ran 27 per cent below normal, which is possible because the water that floods a plain need not have fallen on it.
Upstream rain
Rain far upstream, around Allahabad and Varanasi, sends high discharge down the Ganga
Record levels
The main river runs at or above its highest flood level (HFL), the highest it has been recorded at that gauge
Backwater effect
Tributaries such as the Gandak and the Punpun cannot discharge into it
Spill
They spill over their own banks instead
Spread
Silt raised beds and flat plains carry the water far across low lying land
- September rain was 31 per cent above normal and fell in heavy local spells.
- Water released from Nepal was not the main cause, so the fix is basin wide rather than bilateral.
- Embankments cut rivers off from their floodplains.
- Many people live on diara, the low riverine tracts that lie within the river's reach.
See also: Farakka Barrage
The Indian Express, 12 Sep 2026: Bihar floods underline need for basin-wide cooperation (editorial) (opens in a new tab) · The Indian Express, 10 Sep 2026: Bihar is flooded despite poor rains. Nepal is not the reason (opens in a new tab)
5 Aug 2026 · Prelims and Mains
Mission Mausam
A warning can only be as good as what the country is watching with, so India's answer has been to buy the watching first. The programme gathers radars, automatic weather stations and global artificial intelligence models into one network.
- weather modification
- Deliberate intervention in the atmosphere, such as seeding clouds, to change how much rain falls.
50Doppler Weather Radars with the India Meteorological Department
1,008automatic weather stations
174seismological observatories, against 86 in 2014
₹2,000 croreMission Mausam phase one outlay, 2024 to 2026
- Mission Mausam is the Ministry of Earth Sciences programme to widen India's observing network, sharpen its models and take up weather modification research.
- Phase one built most of the network the country now warns from.
- A second phase runs from 2026 to 2031 through six verticals, of which weather modification research is one.
- Its targets are set for 2030: forecasts 10 to 15 per cent more accurate, and hazard forecasts on a 5 km by 5 km grid reaching every household.
- Those targets therefore fall inside this second phase and not the next.
See also: Doppler Weather Radar
PIB, 5 Aug 2026: Mission Mausam and India's early-warning network (opens in a new tab)
9 Sep 2026 · Prelims and Mains
Doppler Weather Radar
A forecast becomes a warning only when something watches a storm as it builds, and in the hills the terrain works against the instrument that does.
- cloudburst
- Sudden very heavy rain, taken by the India Meteorological Department as more than 100 mm in an hour over a small area.
- Doppler effect
- The shift in a wave's frequency when its source and observer move towards or away from each other.
- A Doppler Weather Radar sends out a microwave pulse and reads the echo returned by raindrops, snow and hail, which tells it where precipitation is and how heavy it is.
- The Doppler effect in that echo also gives the speed at which those drops are moving, so the radar reads the wind inside a cloud and not only the rain falling out of it.
- Because it scans again every few minutes it follows a storm or a cloudburst as it develops, which is what turns a forecast into a warning.
- A radar beam travels in a straight line, so a ridge standing in front of it blocks the beam and the valley behind that ridge goes unwatched, which is beam blockage.
- Siting in the hills is a trade-off: a radar placed high sees over more ridges, but its beam then passes above the low cloud that is dropping the rain.
- A cloudburst builds and empties within the hour, so a gap in cover is not a slow loss of accuracy but a warning that never comes.
- Himachal Pradesh was sanctioned two more radars, taking the hill State from three to five, with the Union government funding them.
- The State's case was for cover that the existing three cannot give.
See also: Mission Mausam
- Backwater effect
- Water backing up behind a main river in spate, so a tributary cannot discharge into it and spills over its own banks.
Also filed elsewhere
- Heat Action Plans · on India's climate policy: NDCs, net zero and adaptation
Extreme heat is met city by city rather than nationally, which is at once the strength of the instrument and its limit.
- Himalayan forest fires · on Forests, grasslands and mountain ecosystems
The Parliamentary Standing Committee on Science and Technology, Environment, Forests and Climate Change, in its 412th report, found no study linking climate change to rising Himalayan forest fires, and what the range does have is two fire seasons with different causes.