A method for providing alerts for a traffic slowdown includes receiving location data for at least a first vehicle of a plurality of vehicles, map matching the location data for at least the first vehicle to a road network, calculating an approaching speed for at least the first vehicle at a first time, calculating a final speed for at least the first vehicle at a second time, and generating a traffic slowdown message in response to the approaching speed and the final speed. The traffic slowdown message includes at least one characteristic of the traffic slowdown.