Organic dome modelling

Hi there, I have a very simple surface to model. However I am not able to know the process. Would be appreciate if anyone can helps. Please see the attached image.

Thanks heaps

Maybe network surface command. Or you can place two points at two corners and use sweep2 ? Or make a four side surface and draw that round shape from top view and trim surface.

The secret is understanding that NURBs surfaces are always 4-sided.
You can then have a different outer shape by trimming the surface.
Turn on each layer one-by-one to see the steps:
trimmed.3dm (534.5 KB)