Thanks Bruce and Shu! @Bruce, That's pretty much the way the scene looked, with the setting sun glancing the undersides of the clouds. I've only added a touch of sat in LR to enhance the buildings - if I back it off to neutral, the clouds look almost unchanged.
Thanks Trav & Sharon! Looked up and saw this as I was getting into my car last night in NYC - just at sunset. Braced against my moon roof frame to shoot straight up long exp. Took 4 or 5, but this is the only one that came out sharp.