Autumn 1942
I missed Summer pictures in Russia. But, essentially, German intelligence had convinced the Soviets that they were going to do their big Summer 1942 offensive in the South and caught the Russians off guard. When the reinforcements did come to the Eastern Front, they mainly got directed to Army Groups North and Center.
In the South, Hoth's panzer army seized the Donbas and Stalino, but was stopped by two Soviet fronts under Koniev and Rokossovsky.
The German hammer blows in the North caught Soviet Intelligence less prepared. Army Group North, spearheaded by Paulus' 6th Army, took Novgorod and cut the last land supply route to Leningrad. Meanwhile, Army Group Center, led by Manstein's 3rd Panzer Army and supported by armies under Weichs and Kleist advanced on Moscow. By the end of Autumn, Weich's had flanked Moscow from the South, taken Tula and ripped a large hole in the Soviet defenses. . . the road through Vladimir to Gorkii was wide open.