The Vikings will play Monday night's game against Chicago at the University of Minnesota's outdoor TCF Bank Stadium.  Investigators deterimined that the tears in the Metrodome roof cannot be repaired in time.  The roof collapsed Sunday morning after a snowstrom dropped approximately 20 inches of snow on the Twin Cities Saturday.  Viking quarterback Brett Favre is not going on injured reserve at least for now according to interim head coach Leslie Frazier.  Favre had an altrasound on his injury throwing shoulder Tuesday and the results were negative.  Frazier is holding out hope that Favre can return this season and maybe this week.  Backup quarterback Tarvaris Jackson has turf toe and is questionable to play Monday night.  Frazier expects the Vikings to sign a free agent quarterback this week that could see playing time on Monday night.  The Vikings play the Bears Monday night at 7:30pm, pregame on WJON at 6:30.