053 FXUS62 KCAE 041205 AAA AFDCAE Area Forecast Discussion...UPDATED National Weather Service Columbia SC 805 AM EDT Sun Apr 4 2021 .SYNOPSIS... Dry high pressure over the region will move offshore on Wednesday. A warming trend will continue through mid-week. The chance for showers and thunderstorms will increase late in the week as an upper level trough and cold front move into the region. && .NEAR TERM /THROUGH TONIGHT/... Frost Advisory expired at 8am. Northwest flow aloft will remain across the region with an upper ridge to the west and an upper low off the North Atlantic coast. Dry surface high pressure will dominate across the southeastern states. We can expect airmass modification with warming temperatures and a slight increase in moisture. Afternoon highs will reach the low to mid 70s with dewpoints near 30. Skies will remain clear through tonight with min temperatures in the low to mid 40s. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... Broad area of high pressure at the surface continues Monday with rising heights as upper ridging builds over the area. Expect another day with plentiful sunshine and temperatures rising to above normal in the mid to upper 70s. Overnight lows remain fairly mild as well in the upper 40s and low 50s. Tuesday the high shifts slightly farther south and east with a weak low pressure system passing well to the north of the area. This will lead to some increased westerly winds at the surface and maybe some high clouds in the northern Midlands but otherwise expect an uneventful weather day with strengthening in the upper ridge leading to highs in the upper 70s and low 80s. Tuesday night an upper low will strengthen over the Plains but with the ridge still hanging on over the Southeast, no impacts are expected until the second half of the week. Overnight lows in the low to mid 50s. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... High pressure looks to hang on one more day before the previously mentioned upper low begins to deepen and move east. Some slight moisture return expected Wednesday, although for much of the day the flow remains more zonal. Expect the deeper moisture to begin to move in Wednesday night with a deep SW flow developing and PWATs rising to near an inch in the western area by Thursday. Only a couple ECMWF or GEFS ensemble members put any measurable rain across the area before 8 AM Thursday so kept the forecast mostly dry Wednesday night. Warm advection ahead of a cold front both Wednesday and Thursday will favor highs in the low to mid 80s, expected near the consensus of MOS. Ridging may hold a bit Thursday in the eastern forecast area with a shortwave moving through the west with chances of showers highest in the Piedmont. While the signal is probably strongest among GEFS members, limited instability may be present Thursday with a bit more Friday so have kept the slight chance for thunderstorms mainly in the western area Thursday and chance for thunderstorms across the entire area Friday as the ridge really breaks down and the actual cold front pushes through the area. Uncertainty remains as to the evolution of the front as it moves into the Coastal Plain, whether it stalls or remains progressive with fairly significant spread amongst GEFS plumes for precip Saturday. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... VFR. Dry high pressure will reside over the region with clear skies. Light wind will become west-southwest 5 to 10 knots after 14z. EXTENDED AVIATION OUTLOOK...Late night/early morning shallow river valley fog may affect AGS. Otherwise, no significant impacts expected through Wednesday. The chance for convection and associated restrictions returns Thursday as a strong low pressure approaches from the west. && .CAE WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. && $$