textproduct: Greenville-Spartanburg

WHAT HAS CHANGED

Rain and snow amounts are trending lower for the mountains.

Updated aviation section for 18Z TAF issuance.

KEY MESSAGES

1. Slightly warmer temperatures tonight as dry conditions persist through midweek. 2. Precipitation chances increase late in the week, including the potential for mountain snow as much colder air overtakes the region.

DISCUSSION

Key message 1: Slightly warmer temperatures tonight as dry conditions persist through midweek.

High pressure continues over the southeast into midweek ahead of the next potential system. Relatively quiet pattern through midweek as temps warm to normal and conditions remain dry. Temperatures overnight look to be slightly warmer, reducing chances for frost. Cannot rule out some frost forming on elevated surfaces, especially in the mountains. After tonight, gradual moisture return increases overnight temps across the entire CWA.

Key message 2: Precipitation chances increase late in the week, including the potential for mountain snow as much colder air overtakes the region.

The bigger story turns to the next system looking to move in at the end of the week. Synoptically, an amplifying ridge out west develops a strong trough downstream by Thursday. At the surface, a strong continental polar airmass looks to spill into the central and eastern CONUS, bringing the coldest temperatures of the season to the area. Meanwhile, guidance depicts a developing surface low that crosses the Ohio Valley and lifts northeast. Latest trends have put the low slightly further south, but still mostly out of the region. The main impact from this system looks to be the first snow of the winter season for the mountains. As the low lifts northeast, colder air looks to wrap around and head toward the mountains. Lingering moisture at the NC/TN border Thursday night into Friday night could bring measurable snow for some locations along the spine. At this time, this NW flow snow event is trending drier from previous model runs, but still on track for snow accumulations. Locations along the NC/TN border look to have a 30-50% chance for 2" or more of snow accumulations. Depending on how model guidance trends as the event nears and confidence in snow amounts, will determine if a Winter Weather Advisory is needed. Once the snow chances taper off Friday night, confidence is increasing that widespread freezing temps are likely for Friday and Saturday nights. As a reminder, the growing season is considered done after November 11 and no freeze products will be issued for any part of the CWA afterwards.

AVIATION /18Z MONDAY THROUGH SATURDAY/

At KCLT and elsewhere: VFR conditions prevail through the TAF period at all sites. Winds become light and VRB through the overnight hours with calm winds at KHKY/KGSP/KGMU. KCLT should pick up again from the SW Tuesday afternoon. BR is possible again at KAND for a brief period Tuesday morning so a TEMPO from 11z-13z should suffice for 2SM vsby. Skies remain SKC and not other restrictions anticipated.

Outlook: VFR through Wednesday, outside of some patchy mountain valley fog/low stratus each morning. A cold front may bring precipitation and associated restrictions Thursday into Friday.

GSP WATCHES/WARNINGS/ADVISORIES

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