Dangerous heat hits US with temperatures forecast to reach 115 degrees

Dangerous heat is enveloping a large swath of the U.S., with temperatures forecast to climb above 100 degrees Monday from California to Arizona to Texas to Missouri.

Temperatures on Monday could reach a scorching 111 degrees in Redding, California; 114 in Palm Springs; 112 in Las Vegas; and 115 in Phoenix.

East of the Rockies, the humidity combined with the heat will make it feel oppressive. The heat index -- what temperature it feels like with humidity -- is forecast to skyrocket to 111 degrees in Austin, Texas; 109 in Houston; 105 in Dallas; 104 in St. Louis and 99 in Memphis, Tennessee.

College Station, Texas, reached a record high temperature of 111 degrees this weekend. At Camp Mabry, a military base in the Austin area, the temperature reached a July record high of 110. Houston's George Bush Intercontinental Airport tied its all-time July record high temperature at 105 on Sunday.

More record highs are possible Monday in Texas, Northern California and Oregon.

This dangerous heat comes as a relentless drought continues to impact much of the West. More than than 75% of the West is experiencing drought conditions; over 97% of California dealing with severe drought.

Some of this heat will stretch into the mid-Atlantic and Northeast on Tuesday and Wednesday, with a forecast of 92 degrees in Washington, D.C., and Philadelphia and 91 degrees in New York. With humidity, it will feel like the upper 90s in some areas.

Click here for tips to stay safe in the heat.

ABC News' Dan Peck contributed to this report.