textproduct: Greenville-Spartanburg

WHAT HAS CHANGED

Thursday is looking drier across our area.

KEY MESSAGES

1. A slow-moving cold front will bring scattered showers and possibly a few embedded thunderstorms to our area this morning. A few more showers and storms may develop over the I-77 Corridor this afternoon, but any coverage should be minimal. 2. Drying high pressure spreads over the area Wednesday into Thursday. Diurnal shower and thunderstorm chances return by the end of the week and continue thru the weekend. High temperatures outside the mountains are expected to climb into the mid to upper 90s this weekend.

DISCUSSION

Key message 1: A slow-moving cold front will bring scattered showers and possibly a few embedded thunderstorms to our area this morning. A few more showers and storms may develop over the I-77 Corridor this afternoon, but any coverage should be minimal.

Another round of light to moderate showers is making its way into the NC mtns from eastern TN, as a few clusters of heavier showers move over the SC Upstate. We've yet to see any lightning from this activity, but I wouldn't rule out a few strikes over the next few hrs, as some elevated instability remains over our area. Otherwise, any severe threat has pretty much ended for our CWA. Based on the latest CAM guidance, the above-mentioned showers will continue to make their way eastward across our area into the morning, but should become more sct as they do. By late morning, any lingering showers should be moving east of our CWA as the actual frontal boundary moves further east. I can't rule out some additional showers and/ or thunderstorms developing this afternoon as the front lingers just E/SE of our CWA, but with little in the way of any upper-lvl support, storm initiation will be challenging.

Key message 2: Drying high pressure spreads over the area Wednesday into Thursday. Diurnal shower and thunderstorm chances return by the end of the week and continue thru the weekend. High temperatures outside the mountains are expected to climb into the mid to upper 90s this weekend.

Drier conditions and somewhat cooler temperatures are expected behind the front on Wednesday. On Thursday, the sfc high weakens and shifts east, as SLY low-level return flow begins to set up over our area. The latest model guidance is slower to modify the drier airmass over our area on Thursday, despite the SLY flow across our area. Thus, any substantial increase in PWAT/deeper moisture is now expected to remain to our south and west. As such, Thursday should be mostly dry with temperatures warming back to near-normal. On Friday, deeper moisture will spread back over our area as another weak frontal boundary approaches from the NW. This will allow for a return of diurnal convection and increasing temperatures from Friday thru the weekend. Over the weekend, highs across the Piedmont are expected to be in the mid to upper 90s, with heat indices exceeding 100 degrees. It is possible that heat products may be needed for portions of our CWA, depending on how much dewpts mix out in the afternoons, and whether or not temper- atures trend any warmer.

AVIATION /07Z TUESDAY THROUGH SATURDAY/

At KCLT and elsewhere: A fairly broad area of showers over eastern TN is about to move into the western NC mtns, though it will likely become more sct as it does so. There's a decent chance that KAVL and KHKY will get some shower activity from this, so I have TEMPOs for -SHRA from roughly 08 to 12z and MVFR visby/cigs. For KCLT and the Upstate terminals, confidence is lower so I have PROB30s and VCSH thru mid/late morning. There is some potential for embedded thunder with this activity, but mostly showers are expected. Any cig re- strictions should lift/sct by late morning, with VFR expected for the rest of the TAF period. Some of the near-term guidance still tries to develop some sct showers over the eastern SC Upstate and southern NC Piedmont this aftn, but this is looking less likely to occur. Otherwise, I still expect a transition to NW flow after daybreak, with low-end gusts carried at all TAF sites.

Outlook: Mostly dry, VFR conditions expected Wednesday and Thursday. Diurnal shower and thunderstorm chances increase again on Friday and continue thru the weekend.

GSP WATCHES/WARNINGS/ADVISORIES

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