XM Satellite Radio said its Navtraffic service will be expanded to include Orlando, Fla., and Tampa, Fla., beginning June 15, bringing the total number of cities served to 22.

The service, launched in fall 2004, uses XM’s satellite constellation to deliver traffic data directly to GPS navigation units. Navtraffic can provide an overlay of color-coded traffic flow information indicating how fast traffic is moving as well as obstructions such as accidents and construction on a driver’s chosen route.