LAS VEGAS—The Southwest United States continued to bake Saturday, and weather forecasters kept warnings in effect for excessive heat in Arizona, Nevada, and desert areas, at least through the weekend. High temperature marks didn’t fall Saturday, but Phoenix reached a sweltering high of 115 degrees F (46 degrees C) for the day and Las Vegas hit 111 degrees F (44 degrees C). Both were three degrees shy of records for the date, forecasters said. Predicted highs on Sunday of 116 degrees F (46.6 degrees C) in Phoenix and 113 degrees F (45 degrees C) in Las Vegas were expected to fall short of high marks for June 20, the National Weather Service said. But Phoenix did set a record Saturday for consecutive 115-degree (46-degree C) days, meteorologist Isaac Smith said, and Sunday could extend the record to six days. Neither city was expected to reach record highs on Sunday of …