Sometimes you can get a pretty good starting blend by stacking one image on top of the other, aligning the layers and then choosing the top layer and using Blend If to limit the top layer to a particular tonal range. In this case, I put the dark layer on the bottom, light layer on top, aligned them and then used Blend If on the top layer and allowed the highlights from the dark layer to show through from underneath. To do this, in the blend if dialog you want to split the Highlight slider (OPT-click) and then pull the left Highlight slider half all the way to the left to the far shadow end of the grayscale. This will progressively blend the highlights from the two images.
Once that is done, you have a low-contra image with the full range of tones resented in the scene. You can use whatever tools you would like to increase global and local contrast, balance and edit color, etc. I gave the image a more painterly, super saturated look, but you could take this one in all sorts of directions. The sky is highly compressed and blocky in the posted preview images, so when you are lightening the sky and pushing the color contrast there, you reveal the limitations of the previews.
I went a little lighter than the doomsday sky look because, you know, there's no place like home....
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