Forecast low for night (sprinkler monitor)

One of my uses for the forecast is to know if I need to winterize the sprinkler before night time. The current day high/low display is for the midnight to midnight time. While I understand that is technically correct, it would be nice to have an option to change the high/low time period (sunrise/sunset would be great.) I’ve read in other posts that there are really no standards so it would be hard to accommodate all preferences. I understand, but a simple entry could just take the day forecast and shift the results by a certain number of hours.