The signal interruptions will affect aircraft GPS navigation systems, but not cell phones or other devices. Last year the USAF tested the new jamming software in exercises in Alaska.
The aircraft approach and departure areas around KLAS (Las Vegas) will be the most likely affected, but not the entire Western US. This is because RED FLAG 18-1 is being conducted out of Nellis AFB near Las Vegas, which will be using aircraft that transmit the jamming signals.
It would be interesting of anyone notices any automobile GPS hic-ups. Probably unlikely, since the radio frequencies involved are different. Read this regarding frequencies:https://www.gps.gov/systems/gps/modernization/civilsignals/.
This article has information about testing that was conducted out of Holloman AFB, New Mexico and Edwards AFB, California: http://www.af.mil/News/Article-Display/Article/1309991/dod-academia-test-systems-for-gps-denial/