A potentially deadly heat wave is expected to bear down on parts of Arizona and California this weekend.
Temperatures are predicted to soar well past 110 degrees and perhaps top 120 degrees beginning on Friday in the deserts of southeast California and southern Arizona, Weather.com and the National Weather Service said.
Forecasters said highs could top 118 in Phoenix on Saturday, potentially setting a new record for that date in the Arizona capital, and increasing the risk of heat stroke and exhaustion.
"Exceedingly high temperatures can cause heat-related illness, including death,'' the National Weather Service said in an excessive heat warning that will be in effect between 8 a.m. Friday and 8 p.m. Sunday. The agency added that residents without air conditioning are most vulnerable during the period covered by the warning.
Authorities are also concerned about the risk to undocumented immigrants trekking through southern Arizona, where shade is scarce and temperatures are expected to reach between 115 and 121 degrees over the weekend.
"It's a very dangerous situation to have anyone out in these remote areas,'' Brent Cagen, a spokesman for the Tucson sector of the U.S. Border Patrol, told Reuters. "We definitely see a rise (in rescues and deaths) when it gets to be 115 or 120 degrees out in the desert,'' he added.
Cagen also told Reuters that Border Patrol agents, including 250 specially trained as emergency medical responders, carried out 374 rescues between Oct. 1 and May 31. Ninety-nine deaths, most from exposure, were reported during that period.