textproduct: Greenville-Spartanburg

WHAT HAS CHANGED

The aviation forecast was updated for the 00z TAF issuance.

KEY MESSAGES

1. Another Heat Advisory has been issued for Monday for Upstate SC, northeast Georgia, and the Charlotte Metro area. Hot and humid weather continues for most of the week, with triple digit heat index likely over the low terrain each afternoon. 2. Diurnal convection develops each afternoon this week, with some strong to severe storms as well as isolated nuisance flooding possible each day.

DISCUSSION

Key message 1: Another Heat Advisory has been issued for Monday for Upstate SC, northeast Georgia, and the Charlotte Metro area. Hot and humid weather continues for most of the week, with triple digit heat index likely over the low terrain each afternoon.

Stout subtropical ridging slowly retrogrades thru the period, but not fast enough to significantly lower heights and thicknesses until later in the week or next weekend. With the continued heat and humidity, another Heat Advisory has been issued for Monday. There may be enough of a break in the heat or humidity to limit the extent of the Advisories for Tuesday and Wednesday, but that's uncertain at this time.

The guidance continues to suggest a trof forming over the eastern CONUS for next weekend which would allow temps to drop to near or even below normal.

Key message 2: Diurnal convection develops each afternoon this week, with some strong to severe storms as well as isolated nuisance flooding possible each day.

The moist and unstable air mass will remain in place across the area through at least the middle of the week. With steep low level lapse rates, high DCAPE and PW values, wet microbursts will be possible with any storm that can grow tall enough. Severe storm coverage could be higher of Monday with an increase in bulk shear potentially leading to some organization.

By Thursday or Friday, a trof developing over the eastern CONUS could bring a period of more widespread daily convection as a series of shortwaves and a slow moving cold front impact the area into the weekend.

AVIATION /00Z MONDAY THROUGH FRIDAY/

At KCLT and elsewhere: Other than a few lingering showers just south of KGSP, all of the convective activity has dissipated across our fcst area this evening. Expect mainly cirrus overnight with another round of mtn valley fog and low stratus. There's a decent chance that the restrictions will reach KAVL, thus I have prevailing MVFR conditions beginning around 08z with a TEMPO for IFR/LIFR from roughly 09 to 13z. Also have MVFR visby at KHKY beginning around 08z, but confidence is lower there. Any restric- tions should dissipate by late morning. The only terminals that have a mention of showers/thunderstorms for tomorrow are KAVL with a PROB30 for TSRA, and KCLT with just a VCSH. Most of the near-term guidance has the best coverage over the mtns tomorrow. Otherwise, winds will generally be light and VRB to calm overnight. They will pick up from the W to NW Monday afternoon.

Outlook: Scattered showers and thunderstorms and their associated flight restrictions will be possible each afternoon/evening thru Tues. Low stratus and fog will be possible each morning, especially in the mtn valleys.

GSP WATCHES/WARNINGS/ADVISORIES

GA...Heat Advisory from noon to 8 PM EDT Monday for GAZ018-026-028- 029. NC...Heat Advisory from noon to 8 PM EDT Monday for NCZ070>072-082. SC...Heat Advisory from noon to 8 PM EDT Monday for SCZ008>014-019- 104>109.