The Bharat Forecast System

The Bharat Forecast System is a computer weather model. It takes today’s weather readings and calculates how the atmosphere will change. The result is a forecast for the next ten days.

When was it launched?

• The Ministry of Earth Sciences (MoES) launched BharatFS on 26 May 2025.
• The launch ceremony was held at Vigyan Bhawan, New Delhi.
• Dr Jitendra Singh dedicated it to the nation. He is Minister of State (Independent Charge) for Earth Sciences.
• The ministry called it one of the world’s first indigenously developed high-resolution forecast systems.

What does it predict?

• It gives 10-day forecasts of rainfall, temperature and low-pressure genesis.
• The output grid is about 6.5 km wide, per a January 2026 reply. The system is usually called 6 km.
• Its results appear on the NWP page of the India Meteorological Department (IMD).

The answer is IITM Pune, a research institute and not an IIT.

Which institutions were involved?

• The Indian Institute of Tropical Meteorology (IITM), Pune developed it.
• IITM is an institute of the Ministry of Earth Sciences, per the launch release.
• NCMRWF, Noida, and IMD supported the work.
• IITM says it was developed by IITM and operationalised by IMD.

What else did the launch release say?

• Four women scientists spearheaded the effort. The release does not name them.
• The release called the system an Atmanirbhar Bharat and Make in India milestone.
• It said other tropical regions could also benefit.

A weather model cuts the atmosphere into small boxes. It calculates the weather inside each box. Smaller boxes mean finer detail.

What changed from the older model?

• The older global model (GFS T1534) had a grid of about 12 km.
• BharatFS runs at about 6 km.
• The ministry says other operational global centres use 9 to 14 km.
• The ministry also says India is the only country running a global model at this resolution for real-time use. This is a ministry claim.

What is the TCo grid?

• BharatFS uses a Triangular Cubic Octahedral (TCo) grid.
• This design lets the model reach about 6 km over the whole globe.
• The model also accounts for India’s geography, such as the Himalayas and the Western Ghats.

How good is it?

• The ministry says extreme rainfall forecasts improved by about 30% in research mode.
• At launch, the minister cited a 64% gain in “core zones”.
• Later official replies say “significant improvement” over the core monsoon region. An August 2025 reply also gives about 30% better accuracy for extreme rainfall. Treat 64% as a launch-day figure.

A 6 km model needs huge computing power. Two machines made it practical.

What are Arka and Arunika?

• Arka is at IITM Pune. It has 11.77 petaflops.
• Arunika is at NCMRWF Noida. It has 8.24 petaflops.
• The Prime Minister inaugurated both in September 2024. The cost was Rs 850 crore.
• A separate 1.9 petaflop AI and machine-learning system was added.
• Arka means the Sun. Arunika means the glow of dawn.

What difference did they make?

• Runtime fell from about 12 hours to 3 to 6 hours. IITM’s own newsletter says 13 hours to 4.
• That speed allows real-time forecasting.
• The ministry says its computing grew from 6.8 petaflops in 2014 to 22 in 2024. It reached 28 in 2025 (22 petaflops at the 2024 inauguration, 28 per a March 2026 reply).

A coarse grid can miss a small storm. A finer grid can see it.

What does 6 km mean on the ground?

• The ministry says 6 km is about the size of a cluster of panchayats or villages.
• The aim is forecasts at panchayat-cluster level.
• The July 2026 reply says BharatFS serves block levels and then panchayat levels.

Who uses such forecasts?

• Farmers use them for crop planning, irrigation and harvesting.
• Water authorities can manage reservoirs better in the monsoon.
• Disaster teams use them to prepare for extreme rainfall.

BharatFS is one part of a bigger push. That push is Mission Mausam.

What is Mission Mausam?

• The Prime Minister launched it on 14 January 2025. A December 2024 reply gave September 2024.
• Its goal is a “Weather-ready and Climate-smart” nation.
• At the BharatFS launch, the minister gave its budget as Rs 2,000 crore.

How many radars does India have?

• India has 50 Doppler Weather Radars as of mid-2026.
• Older counts were 39 in December 2024 and 48 in February 2026.
• Another 50 are proposed, taking the total to nearly 100 within two years.
• An August 2025 reply says radar data mainly help nowcasts. A December 2024 reply says radar data are fed into weather models.

What are nowcasts?

• A nowcast is a very short-range alert, such as for thunderstorms.
• A 2025 reply says radar-based thunderstorm warnings cover up to 3 hours.
• IMD nowcasts for heavy rain cover up to 6 hours.

Since May 2025 IMD has used the model for operational forecasts.

Is it operational?

• Yes. A March 2026 reply says it was made operational in May 2025.
• IMD uses it to issue operational forecasts.
• The July 2026 reply calls it operational at 6 km.
• Its public outputs appear on IMD’s NWP site. They are not sent directly to stakeholders.

What other tools sit beside it?

• The older GFS and NCUM models run at 12 km. They have been operational since 2018.
• Mausamgram gives village-level forecasts. They are hourly for 36 hours, three-hourly for 5 days and six-hourly up to 10 days.
• IMD developed the Panchayat Mausam Seva portal with the Panchayati Raj ministry.
• On 12 May 2026 the minister launched an AI-driven monsoon advance forecast. It also launched a 1 km rainfall pilot for Uttar Pradesh.

What is still unclear?

• The 64% figure is the minister’s launch-day claim.

Use this order to keep the dates straight.

• Sep 2024: Arka and Arunika inaugurated.
• 14 Jan 2025: Mission Mausam launched.
• 26 May 2025: BharatFS launched at Vigyan Bhawan.
• 2025: MoES computing reaches 28 petaflops.
• 12 May 2026: AI monsoon advance forecast launched.
• Jun 2026: 50 Doppler radars, nearly 100 planned.

How can you remember it?

• Computers came first, then the mission, then the model.
• 6 km is half of the old 12 km.
• IITM Pune builds. IMD runs.