Area Forecast Discussion
Issued by NWS Columbia, SC
Issued by NWS Columbia, SC
034 FXUS62 KCAE 311804 AFDCAE Area Forecast Discussion National Weather Service Columbia SC 204 PM EDT Sun Aug 31 2025 .SYNOPSIS... High pressure building in from the north will result in relatively dry conditions with below normal temperatures through Tuesday. Low chances for precipitation late Wednesday and Thursday as a disturbance passes through, with drier and warmer conditions for late week. && .NEAR TERM /THROUGH TONIGHT/... Key Message(s): -Cool high pressure filling in from the north will yield calm and breezy conditions. Broad troughing is in place across the eastern US, with strengthening northwesterly flow aloft over the area. Northeasterly flow continues to strengthen as well as the corresponding surface high slides into the Great Lakes and New England. A secondary vort max is pushing down through the primary trough axis, and along with some upslope component to the low level flow, is forcing some showers in the Upstate; lapse rates are also notably steeper to our northwest. These showers could drift south towards the western Midlands, but confidence is very low in that given PWAT`s are down around 1.0". Otherwise, breezy winds to roughly 20 mph are likely throughout the afternoon and evening with some residual winds lingering overnight as a moderately strong low level jet develops. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... Key message(s): - Below normal temperatures and very low humidity. A closed upper level low over the Mid-Atlantic on Monday will slowly lift northward and open up as it moves into southern Quebec by Tuesday night. The result will be persistent broad upper level troughing over the region through the period. At the surface, a wave of low pressure will move northeast along a baroclinic zone off the Carolina coast on Monday, acting to reinforce a surface wedge of high pressure which will continue to build down along the lee of the Appalachians through Tuesday. The low-level flow will be northeasterly while the mid/upper-level flow will have more of a northwesterly/westerly component. This will result in very dry conditions across the area with mainly high level cloudiness expected. Very low dew points (HREF mean depicts upper 40s to lower 50s) and precipitable water values (HREF mean depicts PWATs of 0.6-1.0 inches) will keep the relative humidity at levels rarely seen for this time of year. Only slight modification is expected for Tuesday. Temperatures will also be unseasonably cool, with daytime highs in the upper 70s to mid 80s and nighttime lows in the upper 50s to lower 60s. One other note, winds could be breezy at times on Monday as the low-level inversion breaks and a modest low level jet mixes to the surface producing wind gusts upwards of 20-25 mph at times in the late morning and afternoon. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... Key message(s): - Deep troughing favored through the first half of this period, modifying by the end of the week - Light rain possible midweek Long range ensembles depict a deep trough persisting, with a trough axis (and associated short wave energy aloft) swinging through toward the end of the work week. The upper flow will then become more zonal Friday and Saturday. Moisture will gradually increase mid- week, with a front expected to lift north on Thursday. This will present the greatest chance for any precipitation during the forecast period, with blended guidance showing mainly isolated showers and thunderstorms possible Wednesday night and Thursday. A return to drier weather will occur Friday and Saturday as high pressure builds from the northwest. Temperatures will remain near to slightly below normal through mid- week, then rise above normal by late week. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... Breezy VFR conditions expected throughout the period. High pressure is digging into the region with gusty northeast winds expected both today and Monday; gusts up to 20 knots are possible today and 25 knots tomorrow afternoon. Outside of scattered cu, not much to mention in terms of cigs for today or tonight. A strong low level jet and relatively limited moisture should prevent any fog-stratus for Monday morning. Winds around 2k feet late tonight could approach LLWS criteria, but generally expected max LLWS of 20-25 knots from the northeast overnight. EXTENDED AVIATION OUTLOOK...Dry weather generally favored through the extended with low chances for significant restrictions. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...None. GA...None. && $$ SYNOPSIS... NEAR TERM... SHORT TERM... LONG TERM... AVIATION...