textproduct: Columbia

WHAT HAS CHANGED

Expected rain totals ticked down through Monday. Aviation discussion updated for 18Z forecast.

KEY MESSAGES

- 1. Some scattered showers possible Saturday-Sunday with more widespread rain chances Monday, but potential totals have trended down.

DISCUSSION

Key Message 1: Some scattered showers possible Saturday-Sunday with more widespread rain chances Monday, but potential totals have trended down.

A relatively unsettled patterns continues throughout the rest of Saturday through Monday as deep troughing lingers over the eastern US and interacts with a reservoir of gulf moisture. However, the majority of the heavier showers and persistent rain chances are staying to our south as a series of strong MCS's have cut off some of the gulf moisture advection. General instability and high PWAT's could still pop some scattered showers or an isolated t-storm Saturday and Sunday afternoons, especially along and south of I-20.

More widespread showers and storms are expected Monday as a strong shortwave and associated surface front push through, but the potential for notable accumulations has trended down. LREF clusters and overall ensemble guidance has backed off considerably on potential totals from this slowing front for much of the area; generally 0.5-1.0" likely along I-95 and south of I-20, less than 0.25" expected to the north of I-20. Overall the down trend in totals is due to some offshore low pressure development and stronger convection to our south. These both prevent the strongest moisture advection and higher PWAT's from pushing into SC. So the best chances for heavier precip will be focused in the afternoon, closer to the coast and in the southern CSRA. Drier air fills in late Monday and Tuesday with another front moving through on Wednesday.

AVIATION /16Z SATURDAY THROUGH WEDNESDAY/

Generally VFR and MVFR cig conditions likely through Sunday morning before some lower stratus rolls in.

While deeper moisture has pushed into the area, bringing cigs down, rain showers and thunderstorms have remained south of all TAF locations. A few scattered showers are possible this afternoon that could impact terminals, but below confidence for a TAF mention right now. Cigs this afternoon and evening should climb back to VFR with southwesterly winds between 10-15 knots. Tonight, some increasing moisture will push lower stratus into the region with MVFR or IFR cigs likely Sunday morning. Showers will likely sneak into OGB as this push of low stratus moves in Sunday morning, but the rest of the terminals should remain dry. Additional low end rain chances are possible early Sunday afternoon.

EXTENDED AVIATION OUTLOOK...Another system brings a chance for restrictions with showers and thunderstorms last Sunday and especially into Monday.

CAE WATCHES/WARNINGS/ADVISORIES

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