Area Forecast Discussion
Issued by NWS Columbia, SC
Issued by NWS Columbia, SC
571 FXUS62 KCAE 030000 AFDCAE Area Forecast Discussion National Weather Service Columbia SC 800 PM EDT Fri Oct 2 2026 .WHAT HAS CHANGED... No significant changes. Aviation discussion updated for 00z TAFs. && .KEY MESSAGES... - 1. Front approaching the area leading to increasing chances for rain and cooler temps this weekend and into next week. Increasing concern for localized flash flooding. && .DISCUSSION... .KEY MESSAGE 1: Front approaching the area leading to increasing chances for rain and cooler temps this weekend and into next week Increasing concern for localized flash flooding. High pressure has shifted offshore with upper ridging continuing over the forecast area this evening. While there has been a modest moisture increase in the low levels, evident by dew points around 5 to 10 degrees higher than yesterday, much of this increase remains shallow with 12z sounding out of CHS showing dry air persisting in the mid levels. While some light to moderate showers are moving into the southern portion of the forecast area, capping and dry air aloft will limit convective coverage through this evening. As the upper ridge axis shifts offshore into tonight, more significant moisture increase is expected with southwesterly flow developing aloft. HREF mean indicates PWATs will rise to above 2 inches across the forecast area, closer to 2.2 inches near the Coastal Plain. This amount of moisture is unusual for October as the NAEFS is at the 99th percentile. This will lead to widespread cloud coverage and chances for scattered showers in the morning, although forcing will be generally weak so any showers will likely remain light. While instability will generally be weak with blended guidance indication probability of sbCAPE greater than 1000 J/kg around 20 percent or less. As a result, storm coverage may be somewhat isolated, with severe storms unlikely and moderate to heavy rain the main threat. Heaviest will likely be along the axis of the approaching boundary which higher resolution guidance generally favors in the northern half of the area, although the exact location for heaviest rain axis remains uncertain. Trends are leaning towards along and north of I-20 with the heaviest rain setting up from east to west. Strong convergence along this boundary will likely continue into Saturday night and may lead to some general flash flooding concerns into the day on Sunday when upper level forcing strengthens as a robust shortwave likely moves through the area. Coverage looks to be more scattered Saturday and widely scattered Sunday evening with the bulk of the rain likely Sunday into Monday. With moisture anomalously high, the most likely scenario this weekend is widespread rainfall amounts greater than 2 inches, with blended probabilities of 60-70 percent. HREF LPMM indicates this higher axis of greater than 3 inches with localized spots of even higher amounts. Drier air will begin to move in from the north Monday with the axis of heavier rain shifting southward as an upper trough digs into the Northeast. Models have generally been favoring drier air into the middle of next week with cooler air behind the front. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... VFR conditions will generally prevail this evening, though a few showers could briefly lower VSBYs. Scattered showers and storms develop Saturday with better chances for restrictions. Increasing clouds with CIGS around 8-10kft MSL developing this evening. Isolated -SHRA are possible, but confidence remains too low to include in the TAFs. A heavier shower may briefly reduce VSBYs. Moisture will continue to increase through the TAF period, and some MVFR restrictions are possible early Saturday morning, though widespread impacts are not expected to be as significant as in previous nights. Scattered showers and isolated thunderstorms will increase in coverage throughout the day Saturday as CIGS decrease, and periodic MVFR CIGS restrictions are possible. For now, PROB30 groups have been added between 12-18z for -SHRA. Prevailing -SHRA is then more likely Saturday afternoon into the evening. Winds through the period should be light and variable or SLY/SWLY around 7 kts or less. EXTENDED AVIATION OUTLOOK...Scattered to widespread showers and isolated thunderstorms this weekend may lead to restrictions. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...None. GA...None. && $$ DISCUSSION...NS AVIATION...EC