I had accidentally missed the corner of the garden during the last heat spell. The potatoes were overlooked. The irrigation is turned only when the stock tanks need to be filled and the error with the sprinklers caused the problem.
About half of the row are now shriveling and dying. No amount of water will turn around the inevitable.
I’ll give them as much time as possible, but will soon be harvesting the half row and will continue to check sprinklers during the times that I have the irrigation running. (PS as you can see, the pig weeds have no problem growing with or without water, maybe I’m growing the wrong crop)
Schmidlin Angus Farm 
I made the same mistake with my potatoes. I confidently thought they were being watered according to my carefully planned water timer. Then when they were looking peaked, I realized many of the adjustable drippers were turned off. I am now enjoying the harvest of pretty darn good looking potatoes, even though they may be a tad smaller than they might have been.
sorry