I'm far from an expert on this, but last year we had a bad storm (rain) roll through between 2pm and 4:30pm. I waited it out and by the time I got to the field the sun was somewhat attempting to break through the clouds. This field is 50 yards wide & 500 yards long of blue stem that had standing corn where I was planning on completing my 500 yard push and the remaining 3/4 was picked bean field. My thinking was they'll want to get their feathers somewhat dry as the rain had stopped, so I tired this field out due to the majority of the area around this strip was not tall. Right away I observed birds on the edges and pushed this field and got my limit in 40 minutes. I saw so many birds though it was crazy and made for a fun hunt. Although if all else fails hit the thick stuff where they are more protected from the elements.
Good luck!