A bushfire has jumped the South Australian border with residents in Victoria warned it could become dangerous and unpredictable as temperatures soar.

A bushfire that has spread from South Australia into Victoria may become dangerous and unpredictable amid hot temperatures, authorities warn.

Victorian residents in the far west, near the South Australian border, have been told leaving now is the safest option if they are not prepared to stay and fight the blaze.

The Watch and Act warning has been issued for Langkoop, Poolaijelo and Powers Creek as the grassfire at Poolaijelo burns out of control.

“Don’t wait — if you are not prepared to stay, leaving now is the safest option,” Victorian emergency authorities warned on Saturday morning.

“Conditions may change and get worse very quickly. Emergency services may not be able to help you if you decide to stay.”

The grassfire is travelling north east and is now burning in the Meereek State Forest.

Temperatures in the low 30s on Saturday in Victoria may cause the fire to become dangerous and unpredictable, with properties potentially impacted, authorities warned.

Firefighters have been working throughout the night and will continue to work with aircraft and heavy equipment on Saturday.

The grassfire at Wrattonbully crossed the South Australian border into Victoria on Friday afternoon.

The fire has now been contained in South Australia but it is actively burning in Victoria.

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