textproduct: Greenville-Spartanburg

WHAT HAS CHANGED

Updated Aviation Discussion.

KEY MESSAGES

1. Mountain valley fog...some locally dense will dissipate shortly after sunrise. Dry with a warming trend today through Saturday. Shower and thunderstorm chances return early next week.

DISCUSSION

Key message 1: Mountain valley fog...some locally dense will dissipate shortly after sunrise. Dry with a warming trend today through Saturday. Shower and thunderstorm chances return early next week.

Fog and low stratus has become widespread in the French Broad basin early this morning, with some locally dense fog observed. We are not anticipating the need for a Dense Fog Advisory, and fog is likely to burn off quickly after sunrise. Otherwise, upper heights will be on the rise today, as an amplified upper ridge/associated anticyclone begin building into the Southeast. This will start a warming trend that will continue through Friday, at which point the ridge will be breaking down. Max temps today will still be below normal by 5-7 degrees in most locations. Anomalously low dewpoints in the 40s will make for a quite pleasant day...likely one of the few such days that we will have for the next three-ish months. The air mass steadily modifies through the end of the week, but with the pattern supporting relatively dry surface high pressure and general subsidence, daily moisture/instability will be insufficient for convective development through Saturday. Temps warm to climo by Friday and plateau there through at least Monday as heights steadily fall. By Sunday, the air mass over the region is expected to modify sufficiently to allow for some diurnal convection to fire, mainly over the mountains.

During the early part of the new work week, the global models are in general agreement (although they differ widely in the details) in height falls and perhaps an associated frontal boundary coming into play over our region, with enhanced QPF response over the Southeast and Mid-Atlantic as moisture profiles become more typical of early June. PoPs therefore increase a little above climo (50-60% in the mountains; 30-40% elsewhere) for mainly diurnal convection Mon/Tue.

AVIATION /12Z WEDNESDAY THROUGH SUNDAY/

At KCLT and elsewhere: Fog/low stratus is widespread in the mountain valleys this morning...with KAVL currently reporting VLIFR conditions. Under early summer sun...the fog/stratus should not last any later than 14Z at KAVL. Otherwise, VFR is forecast through the period. Can't rule out more overnight restrictions at KAVL, but conditions currently appear to be less favorable...and any restrictions Thu morning will be most likely in the valleys west of KAVL. Winds will generally be light/variable early...becoming NE and increasing to 5-10 kts this morning, then light/variable again this evening.

Outlook: Dry conditions return and VFR remains into the weekend, except for some potential for daily morning mountain valley fog/low clouds.

GSP WATCHES/WARNINGS/ADVISORIES

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