Patna: Bihar is likely to experience a hotter-than-usual summer in 2026, with temperatures already rising sharply in March and forecasts indicating that the mercury could cross 40°C in the coming months. Weather experts say changing atmospheric patterns, reduced rainfall and geographical factors are contributing to the early onset and intensity of heat across the state.
According to weather observations, the temperature has already reached 36.8 degrees Celsius in March. Meteorologists expect the maximum temperature to remain around 34 degrees Celsius in the coming days, while April could see the mercury touching 40°C.
Private weather forecasting agency AccuWeather has predicted that between April 12 and April 26, the maximum temperature may remain at 39°C or above in several parts of Bihar. Similarly, from May 15 to May 26, temperatures may cross 40°C, accompanied by heatwave conditions.
Why summer arrived early
Weather experts attribute the early arrival of summer to the absence of strong western disturbances over northern India. Western disturbances are weather systems that originate near the Mediterranean Sea and travel eastward, carrying moisture through regions such as the Gulf countries, the Black Sea and the Caspian Sea before reaching the Indian subcontinent.
When these systems hit the Himalayas, they usually cause rainfall and snowfall in the mountains, which in turn brings rain and cooler temperatures to the plains. However, meteorologists say no major western disturbance has been active over India since November 2025. As a result, winter conditions weakened early and temperatures began rising rapidly.
This led to the winter season ending in February in Bihar, with heat setting in earlier than usual. In the first 12 days of March itself, temperatures crossed 35°C in several places.
Low rainfall intensifying heat
Officials from the India Meteorological Department (IMD) say the intensity of summer has been increasing every year. According to weather data, temperatures in 2024 were higher than in 2023, and 2025 recorded more heat than 2024. Early projections suggest that 2026 may turn out to be even hotter.
Typically, summer conditions dominate April, May and June, but this year the heat began intensifying from March. Meteorologists believe the main reason is the early end of the rainy season and declining rainfall over the years. Monsoon showers have become less intense compared to earlier decades, which contributes to rising temperatures.
Why Dehri in Rohtas records higher temperatures
In recent years, the town of Dehri in Rohtas district has recorded some of the highest temperatures in Bihar, particularly in 2025, 2022 and 2020. Traditionally, Gaya has been known as the hottest location in the state, but the recurring high temperatures in Dehri have raised questions.
Experts say the reason lies in the region’s geographical and climatic conditions. The area is part of the northern plains and lies far from the sea. Unlike coastal regions, inland areas tend to heat up more rapidly. Hot and dry winds blowing from the west and northwest, commonly associated with heatwaves, further increase the temperature.
Why Gaya experiences extreme heat
Gaya continues to remain one of the hottest places in Bihar due to its unique geographical features. The city is surrounded by rocky hills on three sides, and vegetation on these hills is sparse.
These rocky surfaces absorb heat from the sun during the day and release it slowly at night, trapping warmth in the surrounding air. The dry riverbed in the region also contributes to the heat-trapping effect.
Another factor is Gaya’s proximity to the Tropic of Cancer, where the sun’s rays fall more directly. In addition, the influence of the Chotanagpur plateau contributes to higher temperatures in the region. Meteorologists believe Gaya is again likely to record some of the highest temperatures in the state this year.
Rain forecast and weather alert
The IMD has forecast rainfall in parts of Bihar between March 15 and March 19. Light rain may occur at one or two locations in northwest Bihar, north-central Bihar, northeast Bihar and southeast Bihar during this period.
Rain is likely in southwest Bihar on March 16, while south-central Bihar may receive showers on March 16, 17 and 19.
The department has also issued a yellow alert for thunderstorms and lightning between March 15 and March 18. Wind speeds during this period may reach 30 to 50 km/h.
Health risks during changing weather
Doctors have warned that fluctuating temperatures could increase the risk of illnesses.
Senior physician Dr Rajeev Kumar of PMCH said rapid changes in temperature are causing more people to fall sick.
“This is a favourable period for viruses to spread. Viruses generally cannot grow in extremely cold or extremely hot conditions, but moderate fluctuations create ideal conditions for infections,” he said.
Hospitals are currently seeing a rise in patients suffering from allergies, cold, cough and fever. Doctors also report an increase in mosquito-borne diseases such as typhoid and malaria. Seasonal illnesses like measles and chickenpox are also more common during this time.
Impact on agriculture
Agricultural scientists say rising temperatures could affect crop production. Wheat crops in Bihar are currently nearing harvest, and excessive heat may shrink the grain size.
The recent easterly winds have helped keep temperatures balanced for now, but if the heat intensifies, irrigation demand may increase.
Pulses are also nearing harvest, while higher temperatures may reduce germination in maize crops.
Agricultural experts say another growing concern is the pattern of monsoon rainfall in recent years. Although the monsoon arrives on time, rainfall distribution has been uneven.
Farmers have increasingly faced delays in paddy sowing due to insufficient early rainfall. Last year, the monsoon arrived in May, but June remained largely dry. It was only after rainfall in July that paddy crops received adequate water, creating difficulties for farmers across the state.
