Areas recovering from destructive Cyclone Fani will have to endure dangerous temperatures as a heat wave builds across northern and eastern India.

The heat already turned deadly with at least three deaths from sunstroke reported in Andhra Pradesh, according to OneIndia.

Seven deaths and more than 300 people have been hospitalized due to the intense heat since mid-March in Maharashtra, according to The Indian Express.

Just days after Cyclone Fani struck northeast Andhra Pradesh, parts of the state saw temperatures soar above 45 C (113 F).

This heat will continue to build and expand northward through cyclone-ravaged states of Odisha and West Bengal.

Cyclone Fani became the strongest cyclone to strike India in the past 20 years when it made landfall near Puri with winds equal to a Category 3 hurricane in the Atlantic and east Pacific.

The cyclone claimed at least 38 lives in Odisha, 25 of which were in Puri, according to the Times of India. A total of 42 people died in India with more than 10 million people still affected by the storm.

Fani also caused 17 deaths and 45 injuries in Bangladesh as the storm moved inland and weakened. 

As recovery efforts continue, residents and aid workers will face dangerous heat with temperatures near 38 C (100 F) at the coast and 40-43 C (104-110 F) for locations farther inland.

The hottest locations on any given day will endure temperatures near 45-46 C (113-115 F).

The dangerous heat will not be confined to areas that were affected by Cyclone Fani as heat builds throughout all of eastern and northern India.

It will be important for residents to take extra care in the heat to prevent illness. Drinking plenty of water, spending time in the shade and wearing light clothing will be necessary. When possible, strenuous outdoor activity should be avoided during the hottest part of the day.

Stagnant conditions contributing to the high heat will also result in dangerously poor air quality conditions. Face masks should be worn by anyone spending time outdoors. Children, the elderly and those with respiratory or cardiovascular health conditions should avoid spending time outside as much as possible.

More than 6,000 heat-related deaths have been reported in India since 2010, according to the Times of India.