speedometer not working...Tach is 95 3.8 TS

Driving in the storm today i noticed my speedometer is all the way to the right.... past 180 km/h and not moving... the tach is still functioning as is the odometer..... It's snowing pretty heavily and I've done some shifting from drive to reverse getting out of snow.... any idea what could have happened and how to fix????

Is the MIL light on? I suspect it is, with a code P0501 or P0502. Code 501 will set if speed goes from greater than 18 to 0 MPH in less than 2 seconds, brake not applied ( such as rocking out of snow) Pcm defaults, among other things to indicate speedometer may be inop, as will cruise control and TCC. Try disconnecting the battery for 30 seconds to clear codes and if there are no actual problems I suspect speedo should return to normal. If it doesn't let me know and I will sent you the logic tree.
Jeff