Bihar Weather Alert: Thunderstorms and Heatwaves to Clash Across the State Today

KKN Gurugram Desk | While one part of Bihar prepares for thunderstorms and lightning, the other braces for intense heat and humidity. The India Meteorological Department (IMD) has issued Yellow and Orange Alerts for 31 districts due to expected rain, thunderstorms, and lightning, while warning of a severe heat day in seven key cities including Patna, Ara, and Buxar. Weather fluctuations today are driven by a trough line and easterly winds entering the state from the Bay of Bengal.

Top Highlights

• Orange and Yellow Alerts issued for 31 districts

• Thunderstorms, rain, and lightning expected

• Severe heat warning in 7 cities including Patna

• Temperature may drop by up to 3°C in the coming days

• Winds could gust up to 60 km/h in select regions

Dramatic Weather Shift Expected Across Bihar

The weather in Bihar is expected to fluctuate dramatically today, with contrasting conditions prevailing in different parts of the state. The India Meteorological Department (IMD) has predicted a complex mix of severe heat and thunderstorm activity, signaling an unstable atmosphere due to the formation of a trough line and the intrusion of easterly winds from the Bay of Bengal.

While northern and eastern Bihar may experience rain accompanied by lightning and thunderstorms, southern districts will battle with high humidity and rising temperatures, possibly leading to heatstroke conditions.

Heatwave Conditions in Southern Bihar

Severe Heat Warning in 7 Cities

The IMD has placed a Yellow Alert for heat in seven cities in southern Bihar:

• Patna

• Ara

• Buxar

• Arwal

• Sasaram

• Bhabhua

• Aurangabad

These areas are forecasted to experience a “Hot and Humid Day“, characterized by elevated maximum temperatures and high relative humidity, making conditions particularly oppressive.

According to meteorologists, heat indices could soar, making it feel 2–3°C warmer than the actual air temperature. Residents are advised to stay hydrated and avoid prolonged outdoor exposure during peak afternoon hours.

Unbearable Humidity in Patna

The capital city Patna is expected to witness partly cloudy skies, but no significant drop in temperature. Surrounding areas may receive light rainfall or experience thunderstorms, but Patna itself will remain hot and humid, causing discomfort for residents.

The urban heat island effect, common in major cities, may amplify the thermal sensation, leading to increased demand for electricity, water, and healthcare services.

Storm and Rain Warnings in 31 Districts

Orange Alert: High-Impact Weather Expected

The IMD has issued an Orange Alert—indicating more severe weather—for the following districts:

• Supaul

• Araria

• Kishanganj

• Madhepura

• Saharsa

• Purnia

• Katihar

• West Champaran

• East Champaran

• Gopalganj

• Siwan

• Saran

• Buxar

• Bhojpur

• Kaimur

• Rohtas

• Arwal

These areas may experience thunderstorms, light to moderate rainfall, and wind speeds up to 60 km/h. There is also a risk of cloud-to-ground lightning, prompting advisories for people to remain indoors and avoid open areas during storm activity.

Yellow Alert: Moderate Risk

A Yellow Alert has been issued for:

• Sitamarhi

• Sheohar

• Madhubani

• Darbhanga

• Muzaffarpur

• Vaishali

• Samastipur

• Patna

• Begusarai

• Sheikhpura

• Nalanda

• Jehanabad

• Gaya

• Nawada

In these areas, wind speeds may range between 30–40 km/h, and thunderstorms with isolated lightning could occur. Though less intense than the Orange Alert zones, caution is still advised.

Meteorological Explanation: What’s Causing the Shift?

According to the IMD, two primary atmospheric factors are responsible for the changing weather:

1. Trough Line Formation

A trough line (a low-pressure corridor) has developed across Bihar, which is a typical precursor to unstable weather conditions including rain, thunderstorm, and wind disturbances.

2. Influx of Easterly Winds

Moisture-laden easterly winds from the Bay of Bengal are contributing to increased humidity and the formation of cumulonimbus clouds, especially in northern and central Bihar.

These combined systems are not only causing convectional rainfall but also obstructing the free rise of temperatures in many parts of the state.

Temperature Trends: Slight Dip Anticipated

Due to rainfall and cloud cover, maximum and minimum temperatures across the state are expected to drop by up to 3°C in the next 2–3 days. While this will bring some relief in storm-hit districts, southern regions facing heatwave conditions may not experience significant temperature moderation immediately.

Temperature Forecast for Key Cities (Saturday, May 17)

Public Advisory: Safety Guidelines

Residents across Bihar are advised to follow the weather safety instructions issued by the IMD and district administrations:

During Thunderstorms

• Avoid using mobile phones in open areas

• Stay away from isolated trees or electrical poles

• Shelter indoors and unplug electronic devices

During Heatwave

• Drink plenty of water and electrolytes

• Avoid outdoor activities from 12 PM to 4 PM

• Use cotton clothing and cover the head when outside

Bihar’s Weather Technology Boost: AI to Predict Future Storms

In a recent development, Bihar’s meteorology department announced plans to implement Artificial Intelligence (AI) tools to predict storms and lightning events up to 10 days in advance. This advancement is expected to significantly improve disaster preparedness, especially in rural districts where lightning-related fatalities are historically high.

Impact on Daily Life and Agriculture

These erratic weather patterns are affecting daily routines, agriculture, power consumption, and health systems:

• Farmers are reporting delays in fieldwork due to uncertainty in rainfall patterns.

• Power grids are under stress due to rising demand from air conditioning and refrigeration.

• Health concerns such as dehydration and heatstroke are rising, especially among vulnerable populations.

May 17, 2025, will go down as a day of climatic contrast for Bihar—with parts of the state battling violent storms and others wilting under the pressure of heat and humidity.

As these weather fluctuations increase in intensity and frequency, it reflects a broader climate change challenge for India’s densely populated states. Continuous monitoring, rapid response systems, and public awareness are key to minimizing human and material losses.