FL Freeze Warning Issued For Christmas Eve, Crops At Risk

TAMPA BAY, FL — A winter storm that has frozen much of the country is bringing below-freezing temperatures to Florida, putting the state's important agricultural sector at risk.

The National Weather Service in Tampa Bay has issued a freeze warning until 10 a.m. on Christmas Eve, Dec. 24.

A freeze watch remains in effect from late Saturday, Dec. 24, through Christmas morning on Sunday.

A warning means freezing conditions are expected within 36 hours and a watch means conditions are expected in about 48 hours.

The weather service said the freeze warning was issued in anticipation of sub-freezing temperatures as low as 31 degrees in Polk, Hardee, Highlands, coastal Pasco, Hillsborough and inland Manatee counties. The freezing point of water is 32 degrees.

The freeze warning is in effect for most of east central Florida from Friday into Saturday morning.

Additionally, the weather service has issued a wind chill advisory from 1 a.m. to 10 a.m. Saturday for portions of southwest and west-central Florida. Weather experts say there could be wind chills as low as 20 degrees, which could result in hypothermia if precautions aren't taken.

There is a high risk of rip currents at all central Florida Atlantic beaches, and poor to hazardous boating conditions across the Atlantic waters.

A historic winter storm is affecting a majority of the country with more than 60 percent of the population, or 240 million people, under some form of winter weather warning as a powerful Arctic front continues to sweep across the eastern third of the nation, according to the NWS.

Related: How To Keep Pipes From Freezing, Bursting During FL Cold Blast

Winter weather advisories remain in effect from the Canadian border south to the Rio Grande, Gulf Coast and central Florida Peninsula while spanning from the Pacific Northwest to the Eastern Seaboard.

Statewide, the National Weather Service said skies will become cloudy as the cold front bringing frigid Arctic air enters Florida Friday.

Temperatures will quickly fall to the coldest temperatures of the season Friday night. Several hours of freezing conditions are expected for most of east central Florida, with the exception being the Treasure Coast.

The NWS said the freezing temperatures will kill crops and other sensitive vegetation, as well as damage unprotected outdoor plumping.

Residents should bring pets indoors and provide shelter for horses and livestock.

Those who are homeless are urged to seek shelter. All Tampa Bay counties have announced the opening of cold-weather shelters for residents who are homeless or have no heat in their homes. The freezing weather poses the biggest risk to small children and the elderly.

The National Weather Service said residents can expect temperatures to fall to around 29 degrees Friday night. The cold front will also bring 14 mph winds with gusts of 22 mph.

During the day Saturday, temperatures will reach a high near 48 degrees with wind chills as low as 22 degrees. On Saturday night, temperatures will dip to around 28 degrees with more of the same expected for Christmas day and night.

By Monday, the low will be about 35 degrees and will creep back up to 43 degrees on Tuesday night.

The University of Florida IFAS Extension said growers around Central and North Florida are frantically preparing for the freeze, which could potentially wipe out entire fields of crops.

“While we have not had significant freeze damage in recent years, there are increased chances for severe weather events with our current climate conditions,” said Juanita Popenoe, a Lake County UF/IFAS Extension agent who teaches a winter weather school for growers. “With the neutral El Niño phase we are currently in, this is historically where we have had our worst cold weather spells.”

She said frost can easily injure plants by causing ice crystals to form within the plant cells. When these crystals form, water becomes unavailable to the plant tissues, which causes the leaves to appear to be water-soaked, shriveled, brown or black.

She advises all growers to have a freeze protection system in place.

Small acreage and low-growing commercial crops can be covered with straw mulch, plastic, tar paper or reemay cloth to protect them from frost. These coverings work to reduce the heat loss from the ground and plant’s surface, and, in doing so, protect the crops from the drop in nightly temperatures. Covers should be removed during the day when the sun is out.

On small acreage farms, 100-watt lamps can also be used to emit warmth and reduce frost damage. If possible, cluster container plants together underneath the lamp. If the plants or crops cannot be transplanted, then hang the heat lamps, so that their rays cover a larger area.

Using fog clouds can also help farmers protect their crops from frost because the fog reduces the amount of radiative heat loss from the surface. However, it is difficult to maintain the correct fog coverage across all crops.

Most growers use watering tactics to protect crops during a night frost. This involves thoroughly watering the soil during the day. The wetter soil will hold the heat better than dry soil, thus protecting the crops’ roots and keeping the surface temperature from dropping too low.

“Making sure you have enough fuel to run the tanks and understanding the best time to turn the irrigation on can be a challenge," Popenoe said. "If you wait too long, the water will be frozen in the tubes and you cannot protect your crop.”

A freeze also has the potential to kill costly landscaping.

Ed Thralls, a horticulturalist with the University of Florida IFAS Extension, said there are several steps homeowners can take to avoid plant loss when temperatures fall 32 degrees or lower.

• Water your plants: This will bring heat into the soil.
• Cover your plants: Use old sheets or towels to completely cover the plants from the top to the ground. “This traps heat coming from the ground and keeps the plant warm,” Thralls said.
• Set with soil: Use soil and mulch around the edges to hold the cover down. “Bricks and stone won’t keep the heat in, so it’s better to use soil or mulch,” he said.
• Move potted plants: Place them in the garage or under benches on the porch. “The closer you move them to the house, the more heat the plants will get,” Thralls said.
• After the freeze, remove the cover, especially if the freeze is followed by a hot day.

If it’s too late and plants have been damaged by a freeze, he said don’t be in a hurry to prune back the damaged material. The damaged leaves can provide cover for the next freeze event, he said.

“Once freezing weather is over for good, then you can prune the dead leaves,” Thralls said. “You may even want to wait until you see new growth before pruning.”

For more information, click here.