Lights in your house flicker during a storm due to trees and branches coming into contact with power lines which cause a short.
High winds and rain and lightning can affect the power lines and cause the breakers on the power lines to trip and come back on.
In some cases a branch or tree limb can come into contact with the power lines and cause the power line fault detector to trip and come back on and if the fault is not cleared it can cause the power to shut off.
Then a lineman would need to come out and clear the fault and reset the breaker or fuse.
If your lights are flickering throughout your whole house, it can be due to the current weather conditions, such as high winds and storms that can impact power lines.
Other reasons include loose service conductors in your central electrical panel, faulty connectors, worn down wiring, or improperly connected wiring.
The dimming and flickering in your lights is caused by the current surge when the circuit breaker trips and is reset, perhaps into a short circuit.
Probably on the circuit from your energy provider to your house there are some bad contacts on the wires, that get affected by bad weather.
If your power goes out and stays out then you should always call your electric company to let them know.
Then they will send a lineman out to start looking for the problem and to restore power as quickly and safely as possible.