textproduct: Greenville-Spartanburg

WHAT HAS CHANGED

Updated the aviation discussion.

KEY MESSAGES

1. Mainly diurnal convection through much of the next seven days, with hotter-than-normal temperatures expected late this week.

DISCUSSION

Key message 1: Mainly diurnal convection through much of the next seven days, with hotter-than-normal temperatures expected late this week.

Areas of fog and low stratus this morning will dissipate relatively quickly after daybreak. The tail end of a shortwave crosses the area this afternoon. This combined with a weak boundary from a dissipated overnight MCS will provide forcing for a line of convection to develop and cross the area from the northwest with near normal diurnal timing. Instability and shear will be weak, but with good forcing a few strong or severe storms are possible. Isolated heavy rain is also possible, but will be more limited than we saw on Tuesday.

An upper ridge builds over the area through Friday before a series of shortwaves bring more zonal flow for the weekend and even a trough developing early next week. The result is hot temperatures developing over the area, with Friday being the hottest day. Right now, it appears the model blend in on the high end of guidance. While the probability of highs above 90 outside of the mountains is very high Thursday through Sunday, the probability of highs above 95 is quite low for our area, more likely to our east and south. Therefore, have gone a little below the blend for highs. This still brings heat index values near 100 for Thursday and around 100 on Friday. Temps then slowly fall to around normal as heights fall with the zonal flow and trough.

Diurnal convection continues Thursday through the weekend favoring the mountains each day due to the ridge limiting instability or creating high LFC's outside of the mountains. Chances increase across the area early next week with the height falls and shortwave activity.

AVIATION /12Z WEDNESDAY THROUGH SUNDAY/

At KCLT and elsewhere: LIFR to VLIFR at KHKY, KAVL, and KAND will scatter out/dissipate by 14Z. Restrictions are looking less likely at the other sites this morning. That said, can't rule out a brief MVFR cig as there are clouds at that level floating around. Then cirrus continues with VFR Cu for the afternoon. A line of convection develops and sweeps across the area with a near normal diurnal timing. Fog and stratus return overnight at KAVL and KHKY. Light S to SE winds this morning, N at KAVL, pick up from the S to SW during the day, then back light overnight.

Outlook: Diurnal convection and associated restrictions are expected into the weekend. Mtn valley fog and low stratus are possible each morning.

GSP WATCHES/WARNINGS/ADVISORIES

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