textproduct: Greenville-Spartanburg

WHAT HAS CHANGED

The aviation forecast was updated to reflect the 12Z TAF issuance.

KEY MESSAGES

1. NW snowfall will continue into Saturday morning across the higher elevations along the Tennessee border. 2. Gusty winds and colder temperatures behind a strong cold front will linger through the weekend.

DISCUSSION

Key message 1: NW snowfall will continue into Saturday morning across the higher elevations along the Tennessee border.

Steep upper ridging will persist to our west while broad/deep upper trofing dominates downstream over the eastern CONUS. A cold front is now east of our fcst area with broad Canadian high pressure gradually spreading colder air across the western Carolinas. Although the bulk of the moisture will mostly mix out with the addition of the drier air from the NW, the NW flow and lingering low-level moisture along the NC/TN border increases the chances for the season's first snow. Overall, most of the latest model guidance doesn't appear to have changed significantly wrt QPF and/or snow amounts over the impacted areas. While a few locations outside the Smokies could see snow accumulations, the higher elevations of the Smokies (i.e., above 4500 ft) will have the best chance for accumulations, anywhere in the 2 to 6 inch range. Outside the Smokies, most locations along the NC/TN border are expected to get less than 2 inches. Model soundings continue to depict some amount of instability within the snow growth zone over the higher elevations of the Smokies. If this pans out, an uptick in snowfall amounts is likely over those locations. However, given the warmer temperatures leading up to this event, some of the snow will likely melt early on re- sulting in less accumulations. The issuance of a Winter Weather Advisory is not expected as most locations should receive less than 2 inches of snow. An SPS may be issued as the event unfolds.

Key message 2: Gusty winds and colder temperatures behind a strong cold front will linger through the weekend.

A broad/deep upper trof will remain over the eastern CONUS thru the weekend. At the sfc, a robust cP airmass steadily spreads over our area bringing the coldest air so far this fall. This airmass will keep most of the southeast dry and considerably colder. Cold overnight temperatures Friday and Saturday night increase the like- lihood of a widespread freeze across our CWA. The coldest night is still expected to be Saturday night with temperatures dipping into the 20s to low 30s across our area. We can expect steady warming next week, however temperatures will likely remain below normal thru at least mid-week. As a reminder, the growing season is con- sidered over across our fcst area and no freeze products will be issued for any part of our area going forward.

We can also expect gusty winds to continue across our fcst area, especially over the NC mtns, thru most of the weekend. Wind speeds are expected to remain below Wind Advisory criteria, however some ridgetops could see some 40+ mph gusts over the next couple of days. Elsewhere, gusts should be weaker.

AVIATION /12Z FRIDAY THROUGH TUESDAY/

At KCLT and elsewhere: Still expect mainly VFR conditions for the 12Z TAF period, with the exception of AVL, where periods of MVFR ceiling will be possible the next 2-3 hours. Scattered cu field should develop across the region at FL050-060, persisting for much of the day before dissipating after sunset, and giving way to a night of SCT/BKN altocu east of the mountains...and possible MVFR restrictions at AVL once again. Winds expected to stay out of the NW through the period, gusty through the day, especially at AVL and HKY, and remaining steady, if less gusty, through Friday night.

Outlook: Lingering snow showers through Saturday mid-morning along the Tennessee border, but no impacts expected at AVL other than the aforementioned possibility of a ceiling restriction. VFR returns Sunday onward.

GSP WATCHES/WARNINGS/ADVISORIES

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