The frost/freeze program looks at three different temperature thresholds - frost (36°), freeze (32°) and hard freeze (23°), meaning we issue frost advisories for temperatures of 33-36° when frost is expected, a freeze watch/warning for temperatures of 24-32° and a hard freeze watch/warning for temperatures of 23° or less. Note though, the definition of hard freeze can vary from NWS office to office.
Since frost can form at or near ground level while observed air temperatures are slightly above freezing, frost advisories are issued for the 33-36° temperature range. Air temperatures are observed at a height of 2 meters (6.56 feet) above ground level. At night, heat radiates away from the ground, leaving the air very close to the ground the coldest. Therefore, when temperatures being observed by the sensor range between 32° and 36°, the temperature at ground level may be cold enough to support frost formation, given light winds and high relative humidity.
A basic graphic explaining this concept is shown below:
| Product | Criteria | Suspended |
| Frost Advisory | Issued when temperature is forecast to be between 33° and 36° on nights with calm winds when surface relative humidity is expected to approach or reach 100%. | Suspended for season after the first widespread frost is observed. |
| Freeze Watch | Issued up to 48 hours in advance when temperature might reach 24°-32° for at least 2 hours. | Suspended after after the first widespread freeze for the remainder of the cool season |
| Hard Freeze Watch | Issued up to 48 hours in advance when deep freezing temperatures (23° or colder) are possible any time during the winter season. | These will not be suspended. |
| Freeze Warning | Issued up to 24 hours in advance when temperatures are expected to reach 24°-32° for at least 2 hours. | Suspended after after the first widespread freeze for the remainder of the cool season |
| Hard Freeze Warning | Issued up to 24 hours in advance when deep freezing temperatures (23° or colder) are likely anytime during the winter season. | These will not be suspended. |
The table below summarizes the average first frost, freeze, and hard freeze dates for all of the climate sites in our forecast area based on the current 30-year (1991-2020) climate-normal period. Most locations experience their first frost in early November, first freeze in late November, and first hard freeze in late December/early January. It is important to remember that in the wintertime the Tallahassee Airport is often quite a bit cooler than areas within the city limits.
| Site | First Frost | First Freeze | First Hard Freeze |
| Tallahassee (TLH) | Nov. 10 | Nov. 25 | Dec. 27 |
| Apalachicola (AAF) | Nov. 24 | Dec. 13 | Jan. 13 |
| Panama City (ECP) | Nov. 12 | Nov. 24 | Dec. 31 |
| Marianna (MAI) | Nov. 9 | Nov. 24 | Dec. 27 |
| Dothan (DHN) | Nov. 12 | Nov. 28 | Jan. 8 |
| Albany (ABY) | Nov. 7 | Nov. 18 | Dec. 24 |
| Valdosta (VLD) | Nov. 9 | Nov. 23 | Jan. 7 |
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