textproduct: Columbia

WHAT HAS CHANGED

Updated Key Message 1 and Aviation

KEY MESSAGES

- 1) Dry weather conditions continue into Friday.

- 2) Much-needed rainfall still appears likely Saturday night through Monday. Guidance seems locked in a general 0.5"-1.0" across the area, with higher totals more likely across the northern Midlands.

DISCUSSION

KEY MESSAGE #1: Dry weather conditions continue into Friday.

Dewpoints are starting to recover across the forecast area this evening. However, no significant increase in moisture will occur during the overnight period, with PWATs at daybreak expected to be in the 0.25 to 0.5 inch range.

While temperatures on Friday are forecast to be slightly cooler, another dry day is expected as the center of high pressure traverses the region, with critically low RH values between 20 and 25 percent in the afternoon. Generally light winds will keep fire danger to a minimum, but appropriate precautions should be made if burning on Friday. Modest moisture recovery is expected on Saturday ahead of the next storm system.

KEY MESSAGE #2: Much-needed rainfall still appears likely Saturday night through Monday. Guidance seems locked in a general 0.5"-1.0" across the area, with higher totals more likely across the northern Midlands.

Guidance is in better agreement on the specifics of the upcoming storm this weekend, with a baja low ejecting into the southwestern/southern US on Friday and Saturday. As it does so, our surface high will continue to shift eastward off the coast of the CONUS. Southeasterly flow is forecast to increase across the area and lead to a slow increase in moisture ahead of the surface low and 500 hPa trough. These features should arrive by Sunday, with a warm front lifting through the area gradually during the day. This tends to be a signal in which we would adjust the forecast for at least in-situ wedging. However, the exact details of this setup really don't favor strong wedging developing across the area. Now expecting the warm front to actually end up somewhere across the central or northern Midlands as the surface low approaches from the west. Upper level support should begin to increase Sunday morning, with isolated showers developing Sunday morning as isentropic lift increases. The heaviest rain is generally forecast across the northern Midlands and Pee Dee region, along and north of the warm front. Lift should be maximized here with strong warm and moisture advection. LREF clusters are in good agreement that this area features the highest probabilities of >1" of rain (~40-50% chance). The rest of the area should at least see a good soaking rain with the combination of isentropic lift ahead of the front and heavier rain along the front itself. Some thunder is possible within this band given we'll be south of the warm front (more than likely). So overall, this event does not look super impactful. Instead, we should see a nice, beneficial rain event that we really need.

AVIATION /00Z FRIDAY THROUGH TUESDAY/

VFR conditions expected through the TAF Period.

High pressure will persist over the region through Friday. Satellite imagery showing some intermittent cirrus which should continue through the overnight hours then skies become mostly sunny on Friday. Light to calm winds overnight will pick up from the northeast around 5 to 9 knots after 15z through the afternoon before diminishing a bit towards 00z.

EXTENDED AVIATION OUTLOOK...Restrictions are likely late Saturday through Sunday with a notable rain maker moving into the area.

CAE WATCHES/WARNINGS/ADVISORIES

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