textproduct: Greenville-Spartanburg

WHAT HAS CHANGED

Allowed the Winter Weather Advisory to expire.

KEY MESSAGES

1. The colder air mass lingers over the region through Wednesday night, keeping well below normal temperatures around. Freezing low temperatures will return each night, impacting sensitive vegetation that has already started blooming from the recent abnormally warm weather. 2. Warming trend remains on track starting Thursday and lasting through the weekend. A backdoor cold front still could bring showers on Monday.

DISCUSSION

Key message 1: The colder air mass lingers over the region through Wednesday night, keeping well below normal temperatures around. Freezing low temperatures will return each night, impacting sensitive vegetation that has already started blooming from the recent abnormally warm weather.

Lingering northwest flow snow along the NC/TN border should gradually diminish through this evening before drying up. Upper trough axis will shift east of the CWFA later this afternoon as colder thicknesses remain in place with broad upper troughiness lingering through the middle part of the week. Surface high remains in control as it becomes situated over the eastern-third of the CONUS through Wednesday. A weak mid-level clipper system will dive into the Southeast on Wednesday, which will bring clouds back into the region with some of the high-res guidance suggesting this wave could bring a few snow showers to portions of the NC mountains, mainly along the immediate Tennessee border during the daytime period. Little to no accumulations are expected and with the dry antecedent airmass in place, precipitation will initially struggle to make it to the surface, if at all. Otherwise, cold and dry weather will be in store through Wednesday night with afternoon highs running 15-20 degrees below normal, while overnight lows each night running 10-15 degrees below normal.

Key message 2: Warming trend remains on track starting Thursday and lasting through the weekend. A backdoor cold front still could bring showers on Monday.

Warming llvl return flow develops on Thursday, boosting lower elevation maximum temperatures into the lower 60s. NW NC looks to be on the southern fringe of a period of weak larger scale forcing as a shearing clipper system translates acrs the central Appalachians Thursday night. Model ensembles continue to limit any showers associated with it's passage to locales north of the region. Further llvl warming and rising of upper heights will be seen on Friday with Piedmont maximums fcst to climb into the lower 70s.

Upper heights atop the SE CONUS continue to rise through the weekend supporting maximum temperatures climbing into the lower 80s in the Piedmont. Model guidance is still advertising the passage of another clipper system over the weekend, the effects of which will mainly be limited to locales north of the cwfa with the latest ensemble guidance keeping pcpn chances less than 15 percent this far south.

The inherited slight chance pop for showers will remain for Monday coincident with the approach and passage of back door cold front which ushers in a cooler airmass for next Tuesday.

AVIATION /18Z TUESDAY THROUGH SUNDAY/

At KCLT and elsewhere: VFR conditions will prevail through the forecast period. Low-end gusts will lingering through the afternoon before subsiding later this evening into tonight. West to northwesterly winds will continue through this evening before toggling to a north to northeasterly wind overnight. Winds continue to turn the dial by Wednesday morning with east to northeasterly winds, and finally settling at a southerly component by Wednesday afternoon at 5-10 kts. KAVL will maintain a northwesterly wind before switching out of the south by Wednesday. An increase in mid/upper-level clouds are expected Wednesday morning through the end of the period, but cigs remain at VFR.

Outlook: Mostly dry and VFR through the rest of the week.

GSP WATCHES/WARNINGS/ADVISORIES

GA...None. NC...None. SC...None.