Florida's citrus industry isn't expecting any damage to crops from a deep freeze afflicting much of the U.S. 

Temperatures are expected to dip into the 30s in parts of Florida tomorrow. But Florida Citrus Mutual spokesman Andrew Meadows says temperatures must be at 28 degrees or lower four hours straight for fruit to freeze badly. 

Meadows is optimistic the citrus crop will stand up well to the colder temperatures.  

Fern growers checked their irrigation systems to make sure they will be ready to combat cold weather and shelters opened around the state as Florida prepared for freezing weather.
A hard freeze warning was issued for the northern half of the state. Emergency management officials warned that Monday night was expected to be the coldest night of this winter season, and record-low temperatures were expected to be broken in north Florida.
Temperatures were expected to get as low as the upper teens in north Florida, with the wind chill making it feel as cold as zero degrees.
In South Florida, low temperatures were expected to be around 40 degrees overnight.

Copyright: AP/Photo: Getty Images