Another round of oppressive heat is expected today in south central Iowa. Heat index values will again approach and likely top 100 in the afternoon and early evening hours. State Climatologist Justin Glisan says this most recent heat wave was caused by a dominant high pressure system that prevented cooler air from entering the region, which not only kept it hot, but also dry. Relief is in sight as a cold front sweeps through the region in the next few days, bringing a return of chances for precipitation, with the best opportunity coming Friday night. Daytime highs will drop into the low-to-mid 80s long term as well. Stay tuned to KNIA/KRLS for the latest weather information.