Area Forecast Discussion
Issued by NWS Columbia, SC
Issued by NWS Columbia, SC
963 FXUS62 KCAE 301754 AFDCAE Area Forecast Discussion National Weather Service Columbia SC 154 PM EDT Sat Aug 30 2025 .SYNOPSIS... Showers across south-central SC and the CSRA expected today as a broad trough slides into the eastern US. High pressure building in from the north will result in relatively dry conditions with below normal temperatures Sunday through Tuesday. Low chances for precipitation late Wednesday and Wednesday night as a disturbance passes through, with a return to drier conditions for late week. && .NEAR TERM /THROUGH TONIGHT/... Key Message(s): - Scattered light showers in the southern Midlands this afternoon, otherwise calm weather expected. A broad trough continues to dig into the eastern US, with the trough axis currently pushing through our area. A notable moisture gradient is consequently in place across the region, seen in the surface obs and water vapor aloft, with PWAT`s below 1.0" in the northern and western Midlands but over 2.0" in the extreme southern Midlands. A few showers continue along the moist side of this gradient, downstream of the trough axis, this afternoon. As the trough progresses east this afternoon and evening, northwesterly dry advection aloft with increase northeasterly low level flow will push this moisture gradient further south and rain chances should fall to near zero across the entire forecast area. Some low morning stratus is likely across the southern Midlands on Sunday, but otherwise no notable sensible weather impacts are expected. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... Key message(s): - Drier, with below normal temperatures expected A large upper trough will continue to dig across the eastern CONUS, with a closed low developing over the Mid Atlantic region Sunday night into Monday. Meanwhile low pressure will develop along a baroclinic zone off the southeast coast, reinforcing the surface wedge building southward along the lee of the Appalachians. Unlike typical in-situ wedges, this synoptic setup does not favor any significant moisture advection into the region. Model soundings depict northeast flow prevailing at the surface, with west/northwest flow aloft. In fact, precipitable water values could be 50-60% of normal by Monday. There could be enough mid-level moisture to result in partly cloudy skies on Sunday, with more sunshine looks on tap for Monday. Temperatures will be below normal, with highs generally in the lower to mid 80s and lows in the upper 50s to lower 60s. Breezy northeast flow is expected each afternoon due to a tight surface pressure gradient, with gusts upwards of 20-25 mph possible at times. && .LONG TERM /TUESDAY THROUGH SATURDAY/... Key message(s): - Deep troughing favors cooler than normal conditions through the long term - Light rain possible midweek Ensembles show persistent deep upper level troughing over the eastern CONUS through the long term period. Dry weather will continue through Tuesday, but an approaching short wave trough could increase cloud cover on Wednesday and bring some precipitation late Wednesday into Wednesday night. Operational guidance is once again showing some greater rainfall totals, but blended guidance is not yet on board so uncertainty exists during this period. For the remainder of the period, the deep upper troughing will continue but to what degree is somewhat uncertainty with varying amplitudes depicted by the models. Overall, temperatures will remain below normal through the long term period, with the greatest potential for any rain coming mid-week. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... VFR conditions expected this afternoon and overnight. Some fog- stratus possible in the morning Sunday, primarily at OGB. A slow moving moisture boundary is pushing through the area with a few lingering showers possible at OGB through 20z. Otherwise, precip chances will steadily drop off this afternoon as drier air mixes in aloft. Cigs should continue to remain VFR through the afternoon and evening at all sites. Winds will strengthen this afternoon out of the northeast, with some gusts up to 18-20 knots possible. Stratus is likely Sunday morning, but should remain confined to OGB and possible AGS-DNL; confidence is notably higher at OGB for some MVFR or IFR cigs around sunrise. The setup looks similar for Sunday with a few isolated showers mainly focused in the southern Midlands with some impacts possible at OGB, AGS, DNL. EXTENDED AVIATION OUTLOOK...Moisture advection into the region may lead to early morning stratus or fog this weekend and into early next week. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...None. GA...None. && $$