The Soviets have decided to pull back.
Not only did the fall of Belgorod contribute to this decision, but the Axis were able to surround the initial blocking force before Stalino and had fully secured the Melitopol pocket. Just to top off a bad turn for the Soviets, Dnepropetrovsk surrendered.
It might not be all bad as the muddy season is almost here. Maybe they could have held out a bit longer?
North, note Soviet forces withdrawing to the south east from Kharkov.
South, with Soviet forces also withdrawing from their failed attempt to relieve the Melitopol pocket.
The two pictures well show the shrinking front (both in terms of physical space and troop availability).