As the mercury soars over 40 degrees across the state, Victorians are now being urged to keep electricity usage at a minimum to prevent blackouts.

Melbourne can expect some wild weather over today and tomorrow with thunderstorms settling in on Friday afternoon. The heat is expected to push the power grid to the limit.

The Australian Energy Market Operator has recommended that residents turn down their energy consumption between 1pm and 8pm today. It includes any unnecessary appliances, like your dishwasher and washing machines.

When it comes to your air conditioner, you can still use it, but keep it between 23 and 26 degrees.

On Sunday, Melbourne will finally get cool change which will reset weather conditions.