Hitler's generals were opposed to the plan, but the Fuhrer's will prevailed and the counteroffensive was launched on December 16, 1944, by some 30 German divisions against Allied lines in the Ardennes region. Allied defenses there had been thinned to provide troops for the autumn defensive. Hitler's intention was to drive through Antwerp and cut off and annihilate the British 21st Army Group and the U.S. First and Ninth Armies north of the Ardennes.
Aided by stormy weather which grounded Allied planes and restricted observation, the Germans achieved surprise