Weekend heat wave to bake western US

A construction worker is shown atop a roof at sunrise to beat daytime high temperatures, Thursday, June 27, 2013 in Queen Creek, Ariz. Excessive heat warnings will continue for much of the Desert Southwest as building high pressure triggers major warming in eastern California, Nevada, and Arizona. Dangerously hot temperatures are expected across the Arizona deserts throughout the week with a high of 118 by Friday. (AP Photo/Matt York)PHOENIX (AP) — Tigers at the Phoenix Zoo are getting frozen fish snacks. Temporary cooling stations are popping up to welcome the homeless and elderly. And airlines are monitoring the soaring temperatures to make sure it's safe to fly as the western U.S. falls into the grip of a dangerous heat wave.