Twenty-three deaths were reported on Thursday and another 11 died on Friday, Ballia’s Chief Medical Officer Jayant Kumar said.
“All the individuals were suffering from some ailments and their conditions worsened due to the extreme heat,” Kumar told The Associated Press news agency on Saturday.
He said most of the deaths were because of heart attacks, brain strokes and diarrhoea.
Diwakar Singh, another medical officer, said the people were admitted to Ballia’s main hospital in critical condition.
“Elderly people are vulnerable to extreme heat too,” he said.
India Meteorological Department data shows Ballia reported a maximum temperature of 42.2 degrees Celsius (108 degrees Fahrenheit) on Friday, which is 4.7C (8F) above normal.
The scorching summer has caused power outages across the state, leaving people with no running water, fans or air conditioners. Many have staged protests.