Valley chilled by sub-freezing overnight temperatures, citrus growers brace for frost

Parts of the central San Joaquin Valley cooled down below freezing for as long as five hours Saturday morning, and more below-average temperatures are on the way, the National Weather Service in Hanford said.

Meteorologist David Spector said Merced and Madera counties took the brunt of the chill early Saturday morning. It’s expected to be slightly colder Saturday night and into Sunday morning.

Lows are predicted to stay in the upper 20s and lower 30s in the coming week, with daytime highs in the mid-50s. The next chance of rain comes Thursday.

Carlos Gutierrez grows citrus on 150 acres in Orosi, Lindsay and Porterville. He was prepared for the freezing temperatures, which typically start after Thanksgiving.

“It’s most important to watch things at night,” he said. “It can cost you your whole crop.”

Gutierrez and other citrus growers use wind machines to battle overnight frost. These 40-feet-tall machines blow warmer air down on the fruit, which helps keep any humidity from forming into damaging ice crystals.

Some wind machines automatically turn on once the thermometer reaches 28 or 29 degrees, but most are manually operated. Farmers have to constantly check the temperatures overnight and into the early morning, making citrus farming a 24-hour-a-day job during the cold season.

The frost watch continues into late January or early February, depending on the crop, Gutierrez said. Mandarins, for example, are more susceptible to frost and have to be monitored longer.

Gutierrez begins to harvest his oranges in November and won’t be finished until April or May.

This story was originally published November 28, 2015 at 1:27 PM with the headline "Valley chilled by sub-freezing overnight temperatures, citrus growers brace for frost."