Power should be restored to most Belleville area homes by midnight, but East St. Louis residents likely will experience outages until Monday morning.
Victoria Busch, an Ameren spokeswoman, said that more than 4,370 residents in St. Clair and Madison counties remained without power as of 5 p.m. Sunday.
"We have quite a few poles that were down as well as primary wire down because of the winds," Busch said. "We have to get the primary wire up and then we will be able to restore the distribution lines."
Residents should stay away from downed lines and assume all lines are live, Busch said.
For more information on outages, visit www.ameren.com/outagecenter or www.ameren.mobi. To report a downed line, call 1-800-755-5000.
There were 25 to 30 mph winds in St. Clair County on Sunday, with some gusts blowing about 50 mph, according to the National Weather Service.
The National Weather Service issued a wind advisory for the St. Louis and metro-east that expired 6 p.m.
A wind advisory is issued when gusts are expected to be in the 45 to 57 mph range. Such winds could cause property damage and motorists should be aware of cross winds.
The most intense winds were expected to diminish by sunset, the agency said.