Nighttime and early-morning freezes will continue in the agricultural areas of California through the end of the week.
Tuesday night was the fifth night in a row of freezing or near-freezing temperatures for many growing areas, including the citrus crop.
Before the cold pattern eases, many growing areas will have had a week's worth of temperatures dipping to or below the freezing mark at night.
Porterville and Visalia, which lie near the heart of the citrus growing region, experienced temperatures dipping into the upper 20s Wednesday morning and should drop to or just below freezing Thursday and Friday morning.
According to Shirley Batchman of California Citrus Mutual, "Despite the chill, the freezes thus far have not caused any damage to the citrus crop."
Citrus fruit is somewhat buffered from the cold by the rind.
According to Agricultural Meteorologist Dale Mohler, "Table oranges are grown California, and these oranges have a thick rind."
"Oranges grown in Florida are primarily juice oranges, which have a thin skin and are more susceptible to freezes," Mohler added.
Because most of the groves in California are nestled against the foothills of the Sierra Nevada, there is almost always some sort of breeze stirring at night, preventing the really cold air from collecting over the groves.
If some of the hand fruit has cosmetic damage to the rind, it is generally pushed along as juice oranges.
This electric-powered wind machine produces moving air over the orange trees and circulates rising warm air. (AP Photo/William Wilson Lewis III)
"Wind machines can be used on calm nights to mix the air and prevent the cold from gathering over the groves," Batchman said.
For those not familiar with these devices, they resemble a wind generator. Except they are usually powered by fuel, rather than producing electricity.
The wind machines and other means of frost/freeze prevention may need to be implemented for the balance of the week.
Other crops and sensitive plants are also at risk in the pattern.
Since winds will be dropping off over a broad area at night for the balance of the week, more places may experience damaging temperatures.
According to California Weather Expert Ken Clark, "Wednesday morning was a bit colder than Tuesday morning with frosts in many valley spots."
"Temperatures will slowly moderate beyond Wednesday, but may still dip to freezing or frosty levels into Friday," Clark added.
In the wake of near to slight below normal temperatures during November, much of the Southwest was experiencing temperature departures of 5 to 10 degrees below-average for the first week of December.
During Monday morning, Dec. 6, 2011, at least 16 states west of the Mississippi River experienced below-zero temperatures, including Arizona and New Mexico, where record lows were set.
The danger of this particular episode of frosts and freezes in citrus areas of California should pass by the weekend.
Springlike warmth will pour from the Plains to the East over the next few days before another winter storm unfolds at midweek.
Despite a springlike start to the week, winter and substantial snow will make a comeback across the Midwest and Northeast at midweek.
A storm system will move east through the Rockies and spread snow into the Plains during the day on Tuesday.
Tropical Cyclone Lusi will bring the threat for flooding rains and damaging winds to parts of New Zealand late this week.
Although spring is on the horizon, the detrimental impacts of this year's harsh winter still loom as threats for roof collapses continue.
Record cold outbreak... 30 degree readings all the way to Southern Louisiana; 40-45 degree readings all the way to Florida.
Fort Collins, CO (1998)
5 degrees - tied for the coldest reading of the winter - the first winter on record (since 1889) with no 0 degree readings.
Record heavy snowfall: "one of the most paralyzing snowstorms in decades." Inwood had 48" on the ground by end of the storm.