What is this dark 'cloud' on S1 backscatter?

Can someone in the SNAP community explain what this dark ‘cloud’ is that is visible in the Sentinel-1 SAR backscatter over the India-Nepal border in June 2020?

VV (VH also shows it):

As you can see in the side-by-side comparison with Google Earth, it cuts across different terrains and landcovers. You can also see the dark line of the river through part of it.

It looks like it must be something in the atmosphere but it’s obviously not a normal cloud, can you get this from particulates or ice in a cloud?

Side-by-side with Google, scale bar is 12km:


Where is the data located?
Looks like thick rain clouds to me. Radar, especially short waves, are not fully independent from clouds.


Ah cool, I didn’t realise rain clouds could show up so strongly.

It’s at 27.28 lat, 84.54 long. Here’s the EO Browser link: