textproduct: Greenville-Spartanburg

WHAT HAS CHANGED

Confidence continues to increase regarding the potential for strong to severe storms Monday afternoon and evening. SPC has upgraded areas mainly along and east of I-26 to a slight risk.

KEY MESSAGES

1. Dry today before daily shower and thunderstorm chances return the rest of the week. Strong to severe thunderstorms are possible Monday afternoon and evening with damaging winds being the main hazard.

DISCUSSION

Key message 1: Dry today before daily shower and thunderstorm chances return the rest of the week. Strong to severe thunderstorms are possible Monday afternoon and evening with damaging winds being the main hazard.

Weak sfc high pressure will linger over our area today which should help keep us mostly dry. Most of the near-term model guidance has backed off on PoPs this afternoon/evening which is in line with the latest CAM output. They continue to produce some isolated to sct showers/storms, but nearly all of them are just outside of our CWA. Based on the most recent output, our southernmost zones may have the best chance of seeing some shower activity. With low-level SWLY flow across our area today, temperatures will warm, with highs expected to be just above normal for the first day of summer.

A weak cold front will approach the western Carolinas from the W/NW on Monday, and move thru our area Monday night into Tuesday. A line of showers and thunderstorms is expected to develop out ahead of the front Monday afternoon/evening per the latest CAM guidance. The latest model guidance continues to depict roughly 20 to 30 kts of deep-layer shear ahead of the front and 1500 to 2000 J/kg of sfc-based CAPE across most of our CWA. Thus, severe storms are possible with damaging wind gusts being the main hazard. SPC has upgraded areas mainly along and east of I-26 to a slight risk, with areas west of I- 26 still in a marginal risk. Some scattered storms may develop ahead of the main line Monday afternoon and early evening, mainly across the North Carolina Foothills and Piedmont. The main line has slowed down a bit per the 06Z guidance, with activity not expected to push into the North Carolina mountains until ~6-8 PM. Activity will linger through the late evening hours as it pushes off the mountains. Breezy SW winds can also be expected ahead of the front on Monday, with gusts of 20 to 30 mph expected east of the mountains. Behind the front, a more diurnally-driven convective pattern returns for the rest of the week with highs near normal thru Thursday, and values just above normal for Friday and the weekend.

AVIATION /12Z SUNDAY THROUGH THURSDAY/

At KCLT and elsewhere: Expect dry, VFR conditions to continue at all sites thru the 12z TAF period. Other than a few high cirrus, skies have mostly cleared this morning. We'll likely see a few cumulus and high cirrus again this afternoon across the area. Any lingering fog and vsby restrictions should lift by 13-14Z. Winds will remain light and VRB to calm thru the morning and eventually pick up from the S/SW again this afternoon with speeds between 5 and 10 kts. KCLT will likely see some low-end gusts towards the end of their TAF period later tomorrow morning.

Outlook: Showers and thunderstorms and associated restrictions are likely to return as a cold front moves thru the area Monday into Tuesday. Diurnal chances for showers and thunderstorms continue behind the front for the rest of the week.

GSP WATCHES/WARNINGS/ADVISORIES

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