Heavy rains and dust storm also lashed Uttarakhand, Punjab and Haryana.
Dust storms are common in this part of India during summer but loss of life on this scale is unusual.
The Indian Meteorological Department (IMD) had predicted that monsoon is likely to be normal this year.
Two persons succumbed in each in Saharanpur, Kanpur Nagar, Mirzapur and Hamirpur while one each died in Bareilly, Pilibhit, Chitrakoot, Rae Bareli and Unnao, Mathura, Amroha, Banda, Sitapur, Sambhal, Etawh, Allahabad and Rampur. Officials said most of the deaths were due to collapsed homes.
Dust clouds plunged swathes of north India into darkness as winds of more than 130 kilometres per hour (80 miles per hour) brought down feeble mud houses and killed people where they slept.
James stays flawless in first round as Cavs advance
James' buzzer beating 3 pointer was a devastating blow to IN , but fortunately for them they were able to bounce back IN game 6 . Houston is an outstanding perimeter team and you need all of your weapons at your disposal which they clearly don't have.
"As per figures received till noon, 50 people were killed and 38 injured in the dust storm in different parts of the state", our New Delhi correspondent reports quoting Uttar Pradesh Relief Commissioner Sanjay Kumar.
Numerous dead were sleeping inside when their houses collapsed after being struck by intense bursts of lightning.
Of the casualties, many have been caused by lightning, which struck at many places after the dust storm settled down.
A sudden change in the weather was also reported in the national capital and NCR region. He also said that relief would be given within 24 hours to the affected people. More thunderstorms are expected.
Meanwhile, the Business Standard reported at least 15 flights, including at least two worldwide aircraft, were diverted from Delhi airport due to the bad weather.
The stormy weather comes in the wake of a heat wave that pushed temperatures above 40 degrees Celsius.