This article is about Operation Wintergewitter - Eastern Front. For Operation Wintergewitter - Italian Front, see Operation Wintergewitter - Italian Front. Operation Winter Storm (German Unternehmen Wintergewitter) was the German Fourth Panzer Army's attempt to relieve the German Sixth Army from encirclement during the Battle of Stalingrad during World War II. The operation commenced on 12 December 1942 and was able to advance just halfway to its objective before a Soviet outflanking move further to the north forced the relief force to break off and withdraw, condemning the Sixth Army to defeat and capture. The surrounding of the German Sixth Army by Soviet forces in Operation Uranus had pushed the main body of the Wehrmacht's Army Group South back by sixty to eighty miles. While Fourth Panzer Army's XLVIII Panzer Corps established a line on the Chir River,