The following areas were previously under mandatory evacuations, but were downgraded to voluntary: Amorose, Alvarado A and Laguna A, Alberhill, Glen Ivy A, Glen Ivy B, Glen Eden, Grace, Horsethief A, Laguna A, Matri, McVicker A, Rice and Withrow A.
Nearly 800 homes were under threat, which came out to about 2,800 residents. Along channels, heavy debris flows rushed down hillsides and near the back of homes.
Mayor Natasha Johnson said it was unclear what hillsides could come down and harm neighborhoods.
"We just don't know the stability of our hills anymore. The fire did its devastation and as much as we can prepare for large sums of debris flow, the hills behind us that are not a concern could become a concern very quickly. So that is what takes place when we look at mandatory evacuations," she said.
Residents also captured thick mud flowing down the roads in front of their homes, bringing down mailboxes and dragging trash cans.
Temescal Canyon Road near Lake Street was flooded with murky and muddy waters.
A storm cell is expected to sit over the area for some time and bringing some significant rains. Officials are worried about the amount of debris and rain that could inundate Rice Canyon.
MANDATORY EVACUATION in the following zones was ordered effective immediately today: Amorose, Alberhill, Glen Ivy A, Glen Ivy B, Glen Eden, Grace, Horsethief A, Laguna A, Matri, McVicker A, Rice, Withrow A. MUST GO NOW. @RivCoReady @CtyLakeElsinore #HolyFloodWatch pic.twitter.com/aQUTO3y9SX— CAL FIRE Riverside (@CALFIRERRU) December 6, 2018
Flash flood watches had been issued for the areas. Officials said it was unclear for how long the evacuation orders would be in place, but did expect more rains in the evening.
The rain also caused traffic problems along the 60 Freeway, where several car crashes happened.
Last week's storm brought mud and debris down some canyons and even into some homes not far from the burn scar area.
Residents were urged to heed any warnings and be ready if the storm gets worse.