The farming/gardening season is getting underway and typically in this part of the country, the last spring freeze occurs between April 19th and May 3rd. The National Climatic Data Center (NCDC) also produces frost and freeze maps and these can be found at: http://www.ncdc.noaa.gov/oa/climate/freezefrost/frostfreemaps.html
When necessary, the National Weather Service will issue a
Frost Advisory: Minimum shelter temperature forecast to be 33 to 36°F during the locally defined growing season, on nights with good radiational cooling conditions (e.g., light winds and clear skies).
Freeze Watch: Conditions are favorable for a freeze event to meet or exceed Freeze Warning criteria in the next 12 to 48 hours during the locally defined growing season.
Freeze Warning: Minimum shelter temperature is forecast to be 32°F or less during the locally defined growing season.