textproduct: Columbia

WHAT HAS CHANGED

Aviation discussion updated for 12z TAF.

KEY MESSAGES

- 1. Generally low chances of rain through Friday, favoring the CSRA with a warming trend expected across the area.

- 2. Increased chances of rain over the weekend with highest chances Sunday into Monday.

DISCUSSION

Key Message 1: Generally low chances of rain through Friday, favoring the CSRA with a warming trend expected across the area.

Only a few showers and thunderstorms this afternoon, mainly confined to the CSRA. The PWAT gradient from north to south will generally range from about 1.5" to around 2". Showers and storms that form across the southern Midlands/CSRA will carry potential for some heavier downpours given high PWATs and slow storm motions.

Temperatures will be warming into Friday as broad upper ridging spans the entire CONUS. NAEFS continues to show 850mb temperatures above the 99th percentile both days while even remaining above the 90th percentile through the middle of next week. 700mb temperatures are also above the 97th percentile into the middle of next week. Notably, the bullseye of highest anomalies is generally toward the coastline and eastern NC, so perhaps expect the eastern Midlands into the Pee Dee reach the hottest temperatures during this stretch. From a sensible weather perspective, expect high temperatures to push back into the mid and upper 90s with Friday being the warmest day. Dewpoints were adjusted for today and Friday to account for some deeper mixing which would result in some drier air mixing down to the surface. Still, these values will be in the low to mid 70s and heat indices are expected to rise back above 100 degrees and could reach 105 or higher by Friday.

Key Message 2: Increased chances of rain over the weekend with highest chances Sunday into Monday.

The pattern shifts slightly this weekend as guidance suggests the upper ridge axis will slide just slightly back toward the west. This will leave an opening in the southeast that may allow for an area of tropical low pressure to develop in the northeast Gulf. Models eject this feature quickly along the SC coast and out to sea, but not before it brings some better kinematics to the region and PWATS back over 2". There may also be a secondary feature that moves quickly through the region from north to south and helps enhance the rain threat. As such, the next best chance for precip is likely Sunday into Monday. There may be a slightly better chance of severe weather on Sunday as well given these conditions (better shear, stronger winds, shortwave energy). Also of note, NHC continues to carry a 20% area across the northeastern Gulf into the Carolina's coastline for possible tropical development in the next 7 days.

AVIATION /12Z THURSDAY THROUGH MONDAY/

Mostly VFR conditions are expected throughout the period with brief visibility restrictions this morning.

A front remains south of the terminals early this morning with deep layer dry air generally in place. Brief fog this morning may lead to temporary visibility restrictions at times, although fog remains very shallow and as a result, expecting any restrictions to dissipate quickly this morning. Widespread showers and storms not expected today, although a slight chance for storms will be in place for the Augusta terminals, but probability at this point is below 30 percent. Scattered cumulus around 5kft expected late this morning through the afternoon. Winds will be light and variable this morning increasing to around 5 knots out of the southwest.

EXTENDED AVIATION OUTLOOK...Potential for restrictions from showers and thunderstorms return this weekend.

CAE WATCHES/WARNINGS/ADVISORIES

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