FALCON HEIGHTS, Minn. (AP) - Minnesota State Fair officials and fairgoers are bracing for what could be the hottest stretch of weather at the Great Minnesota Get-Together in 65 years.

An excessive heat warning is in effect through Tuesday for a large part of southern Minnesota and surrounding states through Tuesday. A heat advisory covers the rest of the southern two-thirds of the state. Highs will hit the 90s while heat indexes are forecast to reach 100 to 110. Nighttime conditions aren't expected to cool below the 70s to lower 80s.

Fair officials say 51 people were treated for heat-related issues Saturday, including 10 who had to go to the hospital.

Emergency physicians say they expect to see an increase in patients with heat-related illnesses this week as hot and humid conditions blanket the region.