When planning a visit to Bihar in India, it helps to know that temperatures typically range from 23°C (73°F) in January up to 40°C (104°F) during the peak of May. Our detailed climate overview is based on data from Patna, the region's most well-known city. For more detailed climate information about other cities in the area, please see the section beneath the map further down the page.
The weather in Bihar during January and December is comfortably warm, with average temperatures ranging from 24°C (75°F) to 26°C (79°F).
April, May and June are generally the hottest months of the year.
Precipitation in Bihar varies considerably throughout the year. The wettest conditions occur in July with 323 mm (13 in) of rain, while November stays relatively dry with 5 mm (0.2 in). The region experiences its rainy season during June, July, August and September, when monthly rainfall can range from 190 mm (7.5 in) to 323 mm (13 in). The driest conditions can be found during January, February, March, April, November and December, with rainfall staying below 18 mm (0.7 in).
Visitors hoping to maximize their time in the sun should consider planning their trip for May, when daylight hours are at their peak.