It happened when students arrived at school.
Ameren told Richwoods that the power could be out for three or four hours.
Students, given permission to leave by their parents or guardians, were given excused absences.
When the power was restored just before 8, parents were notified that their child could return to school.
Around 50 students had signed out and most of those students did return to school.
Ameren says more than 1,200 people were left without power in the 61614 area code following the storms.
All power was restored by 10:15 AM.
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