The warning mainly applies to Mjölby, Boxholm, Ödeshög, Ydre, Motala, Vadstena and Ödeshög.
Traffic may go slower as there is a high risk of flooded roads.
As the ground is extremely dry, a downpour-like rain also means a great risk of flooding in basements, stormwater systems and viaducts.
On its website, SMHI writes that there may also be heavy rain in several parts of the country on Saturday and the warning may be extended.
Javascript is disabled
Javascript must be enabled to play video
Read more about browser support
A comparison shows how different types of substrates absorb water.
Photo: University of Reading/SVT