TONIGHT: Mostly clear and comfortable with lows in the mid-60s.
TOMORROW: Mostly sunny and warmer with highs in the upper 80s to around 90. Humidity remains somewhat low.
EXTENDED: Upper level high pressure builds in from the southwest, allowing the jet stream to move north of us. Temperatures will respond to that by Tuesday, with highs getting into the low 90s and humidity increasing. The heat index will rise into the upper 90s. A few storms can't be ruled out, but better chances arise by Wednesday with a disturbances sliding across northern Missouri and southern Iowa. Once that moves out, we're in for a drier end to the week with temperatures increasing to the mid-90s and the heat index near 100 or just above.