A storm that rolled through the Harrisonburg area left the Walmart near Dayton without power.
Emergency crews were dispatched to the store in the 2100 block of John Wayland Highway about 1:30 p.m.
Initial reports indicated the building was struck by lightning, but firefighters determined that an electrical pole supplying power to the structure was hit by lightning.
The building has been evacuated and will be closed until power is restored. Firefighters say the power company has been notified.