43 NC counties and 1 VA county are under alert, including Wake, Cumberland, Durham, Johnston, and Orange counties. Details
Published: 2015-02-17 01:45:00
Updated: 2015-02-17 15:47:44
Posted February 17, 2015
By Greg Fishel
Raleigh, N.C. — The big question entering Monday night was how much sleet would fall as opposed to freezing rain. One freezes before it hits the ground while the other freezes as it hits the ground, or any object for that matter.
Determining which one wins out is next to impossible, as it depends on many factors. First, how much above freezing is the air when it’s several thousand feet above the ground. If that warm nose is well above freezing, the falling rain drops assume the temperature of the air, and it becomes very difficult for them to freeze upon entering the cold air near the ground.
Second, how cold is the cold layer near the ground, and how deep is it? In this case, it was exceptionally cold. Temperatures in the teens with anything but snow falling in North Carolina is very rare. There are no exact thresholds that can be measured to determine whether sleet or freezing rain will be dominant.
Despite what some of you may think, this was indeed a potentially crippling ice storm. A degree or two difference anywhere in the lower 6,000 feet of the atmosphere would have resulted in a much different landscape this morning. We lucked out big time. And if the same situation presents itself in the future, we will handle it exactly the same way.