


Area Forecast Discussion
Issued by NWS Columbia, SC
Issued by NWS Columbia, SC
676 FXUS62 KCAE 101807 AFDCAE Area Forecast Discussion National Weather Service Columbia SC 207 PM EDT Thu Jul 10 2025 .SYNOPSIS... The threat for damaging winds and localized flash flooding will continue across the forecast area this afternoon/evening due to the passage of an upper trough to our north. This trough is replaced by ridging this weekend, allowing temperatures to slowly rise with typical summertime showers and thunderstorms. The ridge breaks down early next week, leading to cooler temperatures and higher rain chances once again during the middle of next week. && .NEAR TERM /THROUGH TONIGHT/... Key Message(s): - Widespread showers and thunderstorms expected this afternoon and evening with damaging winds and flash flooding possible. A slow moving trough will continue to shift eastward today and serve as a focus for convective development. Upper support will gradually increase toward evening, with a shortwave pushing along the NC/SC border. Diurnally driven pulse convection will continue to develop with strong heating, as earlier cloudiness is now dissipating and pushing eastward. As such, low level lapse rates are increasing as temperatures push into the mid and upper 80s, likely settling in the low 90s for highs this afternoon. The surface environment remains muggy with dewpoints in the low to mid 70s. Forecast soundings are saturated through the column, and satellite estimates once again paint the entire forecast area with PWAT values over 2.0". Overall shear remains limited so expect the convective mode will still be pulse, but with storms having a bit more forward motion as southwest flow aloft is slightly stronger. This certainly won`t rule out training, and therefore we`re still concerned about a flash flooding threat. In particular, areas north of the I-20/I-26 interchange will be closely watched due to heavy rainfall and flooding which occurred on Wednesday, boosting antecedent soil moisture levels. Regarding the potential severe aspect, current MLCAPE values are around 1500- 2000 J/kg as any residual CIN continues to erode. DCAPE values are quite low with little dry air aloft, so the damaging wind threat will likely be due to precip loading. Hi-res guidance is consistent in developing a widespread field of convection over the next few hours. Of particular interest is the HRRR solution, which has been developing a line of stronger-looking storms moving through the northern CWA in conjunction with the aforementioned shortwave generally around 00Z this evening, over the last several runs. So we`ll need to see if this comes to fruition, as it may boost the flooding threat further. Overall, another quantity over quality day is expected with at least a few strong to severe storms given the widespread coverage. && .SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/... Key Message(s): - Scattered afternoon/evening showers and storms expected each day. - Temperatures gradually warm through the weekend. The upper trough that has brought more widespread showers/storms will begin its exit Friday as 500mb heights slowly rise through the day and moisture decreases some with mean HREF PWAT`s being between 1.8-2.0" as flow turns a bit more westerly. One last piece of shortwave energy brings another shot at scattered storms during the afternoon and evening Friday, though the recent 12z HREF mean solution and its members depict coverage being less than has been seen the past couple days, likely due to decreasing moisture and heights that will be slowly rising. Storms that do develop however, will bring similar risks to those from the previous days as ample instability is shown in forecast soundings (MLCAPE of 1500-2000 J/kg). With high moisture lingering above a decently mixed boundary layer, some gusty downburst winds will be possible in the strongest storms as they collapse. Due to this potential, the whole CWA is in a Marginal Risk for severe weather Friday (level 1 out of 5). Luckily the influence of the upper trough brings increasing flow aloft and thus while storms in this pulse environment will still have slower motions, they will at least have some steering flow to allow them to translate. Long/skinny CAPE profiles over deep moisture will bring another day with a potential for heavy rainfall and possible spots of flash flooding, especially toward the northern Midlands and a swath from Burke County GA toward Barnwell, Orangeburg, Aiken, and Lexington Counties, where increased soil moistures will make these areas a bit more sensitive to heavy rain. This weekend, upper troughing is replaced with ridging and moisture that returns to more seasonable levels. The building of ridging will allow hot/muggy conditions to move back into the region as heat indices peaking around 100-105 will be possible, mainly Sunday. More typical summertime convection is expected each day as PoP`s become more isolated to scattered each day. && .LONG TERM /MONDAY THROUGH WEDNESDAY/... Key Message(s): - Above normal temperatures on Monday with heat indices peaking between between 100-105. - Upper ridging breaks down into the midweek, bringing near normal temperatures and increase rain chances. The EC Ensemble and GEFS mean 500 mb anomaly solution are in decent agreement with ridging remaining overhead Monday, bringing another day with heat indices that top out near 105 and climatological precip chances. This ridging slowly breaks down during the midweek as an area of low pressure approaches the Bahamas, aiding in turning low level flow more southeasterly to easterly and bringing PWAT`s near 120% of normal and increasing PoP`s. Increased PoP`s look to keep temperatures closer to normal as well into the mid week. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... Periodic restrictions through the TAF period with stratus, followed by showers and thunderstorms this afternoon into this evening. This afternoon, expect SCT-NUM SHRA/TSRA at all TAF sites. Restrictions are expected with the strongest storms due to likely heavy rainfall, particularly impacting VSBYS. Best chance for TSRA generally 19-01z with showers or storms in the vicinity an hour or two before and after this window. Winds with TSRA may be gusty up to around 30 kts. Outside of convective gusts, surface winds generally SLY at 10 kts or less. Debris cloudiness expected overnight with winds dropping to light and variable to calm. Expect additional CIG/VSBY restrictions toward daybreak Friday, particularly at locations which receive heavier rainfall today. Guidance is keying in on CAE/CUB/OGB in particular. EXTENDED AVIATION OUTLOOK...There is the possibility of diurnally driven showers and thunderstorms this week with the potential for periodic restrictions. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...None. GA...None. && $$