A collision avoidance system for snowmobiles includes an array of sensors positioned on a front side of the snowmobile for detecting the presence and location of an approaching obstacle. The sensors include both heat sensors and speed sensors. A control unit is provided for processing signals received from the sensors and outputting audio signals indicative of the detected location of the approaching obstacle. A wireless transmitter transmits the audio signals to a receiver and speaker system contained in a headset or helmet. The speaker system includes left and right speakers contained in the headset or helmet which are adapted to be positioned near or within the driver's left and right ears and provide audible warnings to the driver. The control unit varies a loudness of the audible warnings in the left and right speakers to indicate a direction from which the detected obstacle is approaching.