* WHAT...Thunderstorms will initially develop over the Mogollon Rim and other sky islands of Southeast Arizona during the early afternoon, track southwest into the valleys of Southeast Arizona and become widespread during the late afternoon, then move across the lower deserts of Southeast Arizona through the evening. The stronger storms will produce organized thunderstorm outflow winds between 45-55 mph, resulting in dense blowing dust with visibility between one-quarter and one-half mile and possibly a haboob with near-zero visibility. For the Extreme Heat Warning, dangerously hot conditions with temperatures 107 to 112. Major to Extreme HeatRisk is expected. * WHERE...South Central Pinal County, Southeast Pinal County, Tohono O'odham Nation, and Western Pima County. * WHEN...For the Extreme Heat Warning, until 8 PM MST Monday. For the Blowing Dust Advisory, from 4 PM to 10 PM MST Monday. * IMPACTS...Hazardous driving conditions due to reduced visibility. Heat related illnesses increase significantly during extreme heat events. * ADDITIONAL DETAILS...Warm overnight low temperatures of 84 to 90 degrees in the deserts will provide little to no relief from heat overnight. Warmest overnight low temperatures expected in the Western Deserts.