A pair of freeze warnings have been issued across south central Iowa. The National Weather Service expects temperatures to drop to the upper 20s on Tuesday and Wednesday morning from midnight to 9 a.m. Frost and freeze conditions will kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. The National Weather Service recommends to prevent freezing and possible bursting of outdoor water pipes, they should be wrapped, drained, or allowed to drip slowly. Those that have in-ground sprinkler systems should drain them and cover above-ground pipes to protect them from freezing. Conditions for additional frost and freeze conditions are also possible again on Thursday morning as well. Typically, the last hard freeze of the winter season is in mid-April in the region.