WI: Germany captures Stalingrad as Operation Uranus is launched

What If by the time Operation Uranus started on November 19 1942, the Germans overran
all Soviet forces in Stalingrad and controlled the West Bank of the Volga. Would the POD's
required for this to happen prevent Uranus? If the Operation was still launched would it succeed?

Depends on the details. If the city falls on November 19th, then it doesn't have much of an effect as by the time the 6th Army can pull it's major fighting forces out of the city the Don and Stalingrad Fronts will already be shaking hands at Kalach. If the city fall in September or October, then the OTL Operation Uranus is probably never launched as the whole thing was predicated on the 6th Army being tied down in offensive operations within Stalingrad. Instead, you get a different major offensive operation directed at whichever part of the Axis line is the weakest (probably the Hungarians and Italians on the Don with the aim of capturing Rostov and therefore separating the Axis armies in the Caucasus from the Axis armies in Southern Russia).

What stops the Russians from crossing back across the Volga? German defenses parking their butts right across the river. And if they are invested in preventing the Russians from crossing over, unless they push the Russians off the southern Bank of the Don and farther south from Stalingrad, they can still be surrounded exactly the same way they were.

By late October it makes little difference. By then 62nd and 64th armies have done their job, they've basically gutted 6th Army and prevented Germans from forming mobile reserves, which were always their best defence. Uranus will be bloodier and take longer.

However with entire city in German hands Hitler will be even less willing to abandon it and hell bent on establishing contact only, not withdrawal. What might change is that Paulus would be more willing to launch break out since 6th army is in better shape. Then again, with entire city city in his hands (that is with Germans winning the battle as opposed to OTL failing to do so) he ight be unwilling to abandon such expensive gains.

Even with entire city in their hends Germans can't just empty it and throw everything at Uranus, not with 64th army still going concern and Soviets potentialy launching another Kotluban(-like) offensive