As we are ending 2023, the temperature high and/or low could be consistently at or less than 32°F with a possible chance of snow precipitation. For turfgrass areas in December, the process of dormancy for both warm and cool-season grasses has already occurred. In regards to water use in dormant lawns in cooler temperatures, December is not the time to use irrigation in grass areas. The Photo above is from Pioneer Underground Lawn Sprinklers. https://pioneerunderground.net/sprinkler-winterization-omaha/