SHEBOYGAN, Wis. (WHBL) - Schools throughout the Sheboygan area have shut down for the day and travel is nearly impossible.  The city of Sheboygan is under a snow emergency as of 7:30 this morning.  Six to 8 inches of heavy, wet snow is making travel hazardous.  Sgt. Jason Lierman of the Sheriff's Department said they received more than 100 calls overnight of vehicles either stuck in the roadway or in the ditch.  He said some they were able to get to, some they weren't.  Lt. Bill Adams of the Sheboygan Police Department said travel in the city is also nearly impossible.  He said they had vehicles stuck in the street throughout the city overnight.  Sheboygan Public Works Director Dave Biebel said city crews worked throughout the night to keep emergency routes open and would continue efforts throughout the day.  He said the snow emergency means no parking on snow emergency routes, boulevards, cul de sacs or dead end streets.  Parking in the neighborhoods should be on the odd side of the street.  Biebel also said there will be no garbage pickup today.