What time on a friday afternoons does the 10 east from San Bernardino, Ca. begin to back up.? -

heading east starting from san bernardino, around 4pm, it will be pretty slow, but only for about 10 miles, and nothing terrible (not even stop-and-go). from the 215 to yucaipa, it will be slow, but after that, it is pretty clear and open as you head out towards palm springs.heading east from la, you might as well not leave after noon, like obviousman said. after 8, it will start to clear up.

Any time after noon, depending on the weekend.