This is the shocking moment a store's roof collapsed during a heavy hailstorm that pummelled Brazil.

Dramatic footage captured the ceiling of a home improvement and construction supply shop crashing down as extreme weather swept through Castro, Parana, on Tuesday, August 26.

Local media reported that the violent storm also damaged several public buildings across the area.

Civil Defence officials confirmed around 2,000 people had been affected, with at least 600 receiving emergency assistance.

Authorities have opened the Plinio Menarim gymnasium to shelter displaced residents.

The unusual hailstorm reportedly began at around 9:10 am and lasted just under 20 minutes.

Meteorologist Allef Matos, from Parana's Environmental Monitoring and Technology System (Simepar), said the storm was triggered by a high-level cyclonic vortex moving across the region.