Duke Energy - Winter Weather Information

An upper-level disturbance will approach the area from the northwest today and cross the region tonight. Considerable cloudiness is expected across the region with the possibility of snow showers across the higher elevations this afternoon.  Weak pressure builds across the region through Saturday. Skies will be sunny on Friday, but then considerable cloudiness returns on Saturday with much colder afternoon temperatures.

A storm system will develop over the Plains on Friday and rapidly strengthen over the Lower Mississippi Valley on Saturday, then cross the Southeast on Sunday as a major winter storm. While the models are in fairly good agreement overall, there are some minor differences that result in significant differences in the overall impact.  The first difference is the timing of precipitation onset.  The American model brings precipitation into southwestern NC and Upstate SC on Saturday evening whereas the European model is about 6 hours slower with precipitation not arriving in these areas until after midnight.  There appears to be more model guidance favoring the slower timing, so we will lean in that direction. Also, the European model has a slightly farther south/southeast track over the low-pressure center, which is also better aligned with other model guidance.  The track will determine where the snow/mix line sets up and which locations in the “wintry mix” zone get sleet vs. freezing rain.

Locations northwest of I-85 are expected to receive significant snowfall with this event.  The mountains can expect 12”+ of snow accumulation while the foothills can expect 6-12” of snow accumulation, with significant snow accumulations also possible across far northwestern portions of Upstate SC as well as western portions of the Triad area.  In the vicinity of the I-85 corridor and eastward toward the I-95 corridor, there will likely be a period of snow followed by a prolonged period of significant icing.  What remains unknown at this time is whether this will be sleet (i.e., ice pellets) or freezing rain (i.e., raindrops freezing on contact). The potential exists for widespread 0.25-0.40” ice accumulation across the Piedmont.  If much of this precipitation falls as freezing rain, then power outages will occur as the freezing rain will accumulate on trees and power lines.  However, if much of this precipitation falls as sleet, the impacts will be much lower with the main concern being hazardous roadways. 

Locations near and east of I-95 will have a period of wintry mix followed by a changeover to rain with minimal impacts. The precipitation will wind down on Sunday evening.

Temperatures will be very cold on Sunday. For the western Carolinas, the current forecast calls for readings to be nearly steady in the middle 20s through the morning and early afternoon then slowly rise toward 30 degrees by early evening, then be nearly steady around 30 degrees on Sunday night. For the eastern Carolinas, temperatures will be in the upper 20s in the morning and lower 30s in the afternoon, then warming to the lower 40s in the evening before dropping back into the 30s overnight.