Las Vegas sweats through hottest June on record

June of 2015 was the hottest June in Las Vegas history, the National Weather Service said Wednesday. The average temperature of 91.9 degrees beat the previous record set in June 2013, when the average temperature was 91.5...Seven days in June set records for “high minimums” — days when the lowest temperature was hotter than any in previously recorded history...Weather Service meteorologist Jim Harrison attributed the heat to a long period of high pressure over the Western United States and the “heat island” effect...“There’s a bigger difference in our low temperatures at night than there is in our high temperatures at day compared to 20, 30, 40 years ago,” Harrison said.