The National Weather Service predicts that Las Vegas will see its first 100 degree day of the year early next week, with temperatures expected to reach the upper 90s on Friday and remain above the normal of 85 degrees. The weather service predicts that a "big high pressure ridge" will move into the Southwest, affecting temperatures well above the May normal. This is expected to occur as a "pretty good chance" that the valley will hit the century mark on Monday and Tuesday. Last year, Las Vegas hit 100 for the first time on May 21 and the average date of hitting 100 is May 24. The earliest Las Vegas has hit 100 was May 1, 1947.