Area Forecast Discussion

WHAT HAS CHANGED

Rain amounts have trended slightly higher for Wednesday night.

The aviation forecast was updated to reflect the recent 06Z TAF issuance.

KEY MESSAGES

1. Unseasonably warm and humid conditions are expected for the remainder of the week, with shower and thunderstorm chances increasing today and lingering through Friday.

DISCUSSION

Key message 1: Unseasonably warm and humid conditions are expected for the remainder of the week, with shower and thunderstorm chances increasing today and lingering through Friday.

A modestly active period ensues through at least Friday as trough located west of the area begins to lift toward the northeast, increasing rain and thunderstorm chances. For Wednesday, a weakening frontal boundary approaches from the west with showers and thunderstorms. Ahead of the front, some instability builds in during the afternoon but remains limited due to the anticipated cloud cover. Guidance also hints at weak shear as the front occludes and moves into the area. These less than favorable factors decreases confidence in severe weather coverage. However, cannot rule out an isolated strong to severe storm later today into tonight. Given the southeasterly surface winds, there could be an isolated flash flood risk especially along the Escarpment and foothills. Confidence remains low on in this though. Rain amounts vary in range with this frontal passage with 0.25"-1.5", with the higher amounts likely in the far western NC mountains and portions of Upstate SC and northeast GA.

Behind the front, the CWA remains in a steady southeasterly surface wind regime, funneling moisture into the region and keeping rain chances around. Aloft, a secondary low weakens from the breakdown of the decaying omega block and swings toward the Ohio/TN Valley. Rain chances look to be in the 30-40% for Thursday and increase in the NC Piedmont for Friday as the last bit of forcing pushes through. Guidance has a 20-30% chance for rain totals of 1" or higher for Friday in the eastern zones, which means confidence is lower that rain amounts with the second wave are minimal. Behind this last system, drier air pushes in as surface high pressure spills from the north and spreads into the region.

By Saturday, forecast looks to dry out and have cooler temps closer to normal. Overnight temps for the weekend and into the beginning of next week dip into the 30s for the mountains and upper 30s and 40s elsewhere.

AVIATION /06Z WEDNESDAY THROUGH SUNDAY/

At KCLT and elsewhere: A myriad of restrictions return to the region through the TAF period as moisture surges into the area ahead of an approaching cold front. Low stratus will expand overnight with MVFR to IFR ceilings common. Ceilings will gradually lift through the day, but most will likely remain at least MVFR, although brief VFR could return during the afternoon. Thereafter, a band of showers is expected to cross the area during the evening which will bring associated visibility and ceiling restrictions. A few TSRA cannot be ruled out either, especially at KAND. At least some degree of low stratus will linger into early Thursday morning. Winds will be generally light out of the south/southeast.

Outlook: Showers and associated restrictions will persist into at least early Thursday morning, as a cold front arrives in the region. Consistent improvement is not expected until Friday, when the cold front moves to our east and ushers in VFR conditions for the weekend.

GSP WATCHES / WARNINGS / ADVISORIES

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