The German assault began on 16 December 1944, at 05:30, with a massive artillery barrage on the Allied troops facing the Sixth SS Panzer Army. By 08:00 all three German armies attacked through the Ardennes. In the northern sector Dietrich’s Sixth SS Panzer Army assaulted the Losheim Gap and the Elsenborn Ridge in an effort to break through to Liège. In the center von Manteuffel’s Fifth Panzer Army attacked towards Bastogne and St. Vith, both road junctions of great strategic importance. In the south, Brandenberger’s Seventh Army pushed towards Luxembourg in their efforts to secure the flank from Allied attacks.
The attacks by the Sixth SS Panzer Army’s infantry units in the north fared badly because of unexpectedly fierce resistance by the U.S. 2nd and 99th Infantry Divisions at the Elsenborn Ridge, stalling their advance; this caused Dietrich to make the decision to commit his panzer forces early. Starting on 16 December, however, snowstorms engulfed parts of the Ardennes area. While having the desired effect of keeping the Allied aircraft grounded, the weather also proved troublesome for the Germans because poor road conditions hampered their advance. Poor traffic control led to massive traffic jams and fuel shortages in forward units.
The Germans fared better in the center (the 20 mile (30 km) wide Schnee Eifel sector) as the Fifth Panzer Army attacked positions held by the U.S. 28th and 106th Infantry Divisions. The Germans lacked the overwhelming strength as had been deployed in the north; but they succeeded in surrounding two regiments (422nd and 423rd) of the 106th Division in a pincer movement and forced their surrender. That was a tribute to the way that Manteuffel’s new tactics had been applied. The official U.S. Army history states: "At least seven thousand [men] were lost here and the figure probably is closer to eight or nine thousand. The amount lost in arms and equipment, of course, was very substantial. The Schnee Eifel battle, therefore, represents the most serious reverse suffered by American arms during the operations of 1944–45 in the European theater."The Complete Article