


Area Forecast Discussion
Issued by NWS Columbia, SC
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Issued by NWS Columbia, SC
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-- Discussion containing changed information from previous version are highlighted. --820 FXUS62 KCAE 131028 AFDCAE Area Forecast Discussion National Weather Service Columbia SC 628 AM EDT Sun Jul 13 2025 .SYNOPSIS... Hot temperatures are expected to start off the week with weak upper ridging in place. The ridge then breaks down, leading to cooler temperatures and higher rain chances during the mid-week period. A new upper ridge could build in from the east to end the week with slowly warming temperatures. && .NEAR TERM /THROUGH TONIGHT/... Key Message(s): - Very hot and humid with scattered strong in the afternoon & evening. Weak and broad ridging aloft will continue to build across the Southeast throughout Sunday, with the ridge just upstream of our area. As a result, flow low-deep level flow will shift more westerly- northwesterly on Sunday, but with a very widespread deep moist airmass, northwesterly flow will not do much to drop PWAT`s. Still expected 1.8-2.0" PWAT`s across the area with surface dews points in the 70`s. Like we have seen the last few days, this moisture and plenty of heating will still allow plenty of instability to develop this afternoon; HREF broadly produces 1800-2200 j/kg of ML CAPE by mid-afternoon. There is not any sort of capping aloft despite the subtle ridging, so convection should steadily develop throughout the afternoon as we hit convective temps. Severe thunderstorm threat looks limited with marginal DCAPE, but a few spots of strong- damaging winds are expected, like we have seen the last few days. Besides the convection this afternoon, the heat will notable. Heat indices should climb to around 105F this afternoon with high temps in the mid 90`s and dew points in the mid 70`s. The warmest temps and dews will remain south of I-20 and towards the coastal plain, where any subtle downsloping flow will not mix out to. Its somewhat close to Heat Advisory criteria in spots, but not expected to reach 108F, let alone for two hours. && .SHORT TERM /MONDAY THROUGH MONDAY NIGHT/... Key message(s): - Hot and humid Monday with heat index values near advisory criteria, especially in the CSRA. - Isolated to scattered afternoon and evening convection, most likely in the eastern Midlands. Upper ridging breaks down on Monday due to the combination of a passing trough to our north and an upper low to the south. Its influence should result in another hot and humid day across the forecast area with forecast heat indices between 100 and 105 in the Midlands and 103 and 108 in the CSRA. Will need to monitor trends to see if a Heat Advisory will be required for the CSRA. Regardless, typical heat precautions should continue to be taken when working outside during peak heating. The ample moisture should produce isolated to scattered showers and thunderstorms, especially in the eastern Midlands as the sea breeze boundary moves inland. As is the case during summertime pulse convection, any thunderstorm that develops has the potential to become strong to marginally severe producing damaging winds in addition to small hail, frequent lightning, and heavy rainfall. && .LONG TERM /TUESDAY THROUGH SATURDAY/... Key message(s): - Seasonal temperatures with scattered showers and thunderstorms possible each day. Upper ridge fully breaks down during the mid-week period, resulting in more typical temperatures for mid-July. The Bermuda high will continue to advect a warm, moist air mass from the Gulf into our forecast area with high PWAT values through the extended. Guidance suggests that rain chances will be highest on Wednesday when a weakening cold front may try to enter the region. Beyond this, there may be tropical development in the northern Gulf, but current guidance suggests it will move west as a new upper ridge builds into the Southeastern US from the east. This could cause temperatures to gradually rise, though daily scattered showers and thunderstorms remain in the forecast for the entirety of the long term. && .AVIATION /10Z SUNDAY THROUGH THURSDAY/...-- Changed Discussion --Some low confidence morning stratus-fog possible around sunrise. Scattered storms likely again in the afternoon and evening. Stratus and fog has not materialized as of 10z this morning thanks to some lingering mid-level clouds. We could see some brief sunrise surprise fog-stratus through 13z with some MIFG, so only included a VFR tempo to reflect that. Otherwise light winds, 5-8 knots, will turn out of the northwest for the afternoon with typical summer cu developing through the early afternoon. Scattered storms are again expected this afternoon and evening, with a prob30 mention covering this period. EXTENDED AVIATION OUTLOOK...There is the possibility of diurnally driven showers and thunderstorms into early next week with the potential for periodic restrictions.-- End Changed Discussion --&& .CAE WATCHES/WARNINGS/ADVISORIES... SC...None. GA...None. && $$ SYNOPSIS... NEAR TERM... SHORT TERM... LONG TERM... AVIATION...