RIVERSIDE (CNS) - Extreme heat is expected in the Coachella Valley today and high temperatures are predicted for other parts of Riverside County, according to the National Weather Service.High pressure will weaken today and cause a slight dip in temperatures, but conditions will strengthen on Tuesday and bring temperatures back up through Thursday, forecasters said.The NWS issued an excessive heat warning that will last until 9 p.m. Thursday in the Coachella Valley.High temperatures today will be 89 degrees in Riverside, 103 in the Coachella Valley, 99 in the San Gorgonio Pass near Banning, 75 in Idyllwild, 88 in Lake Elsinore, 85 in Temecula and 89 in Hemet.Nighttime lows are expected to remain in the low- to mid-70s through Thursday in the Coachella Valley, meaning the mi
