Warnings of excessive heat in the American Southwest have forced airlines to cancel dozens of of flights this week.

American Airlines flies certain routes with the Canadian-built Bombardier CRJ aircraft, which is not permitted to fly in temperatures above 117 degrees Fahrenheit. In Phoenix, Arizona, where temperatures are around a scorching 119, American Airlines had no choice but to preemptively cancel seven flights on Monday and 43 for Tuesday.

"Our smaller regional operations—those that use our CRJ aircraft types–will be most affected by the heat," the airline's communication specialist Kent Powell told CNN. "We really aren't expecting any change to the operation with our mainline aircraft."

According to National Weather Service meteorologist Tom Fisher, temperatures in Death Valley in eastern California and in the town of Needles near the Arizona border are expected to reach a whopping 127 degrees this week.



"A strong high pressure aloft over the southwest states will create hot conditions away from the coast at least through midweek, peaking Tuesday and Wednesday," the National Weather Service reported on Monday. "High pressure may weaken slightly the latter part of the week with inland temperatures slightly lowering through Friday."



Several Northern Californian cities broke heat records on Sunday, including Sacramento (106 degrees), San Jose (103 degrees) and San Francisco (88 degrees). The high temperatures have led to power outages in California's Central Valley, the Bay Area and southern parts of the state.

Transportation officials are also looking into whether the extreme heat is behind the buckling of several freeway lanes in West Sacramento on Sunday.