In my experience jap millet seed will germinate in the mud but will rot in standing water. I'd get in in now where it is not flooded and continue to seed following the water down. No rain will be needed. But if you wait until it is dry you will require a rain and weed control.

This came up in mud and out grew the nutgrass and smartweed.

This came up in mud and out grew the nutgrass and smartweed.