


Area Forecast Discussion
Issued by NWS Columbia, SC
Issued by NWS Columbia, SC
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603 FXUS62 KCAE 300702 AFDCAE Area Forecast Discussion National Weather Service Columbia SC 302 AM EDT Mon Jun 30 2025 .SYNOPSIS... Typical summertime weather is expected to continue into the start of the work week, with near to slightly above normal temperatures and daily shower and thunderstorm chances. More widespread showers and storms Tuesday and Wednesday and slightly cooler. Summer pattern returns for the second half of the week. && .NEAR TERM /THROUGH TONIGHT/... Key Message(s): - Upper trough becomes diffuse with near normal temperatures - Scattered afternoon/evening showers and storms The upper trough that has been over the region for several days becomes diffuse while the upper ridge over the western Atlantic ridges into the area. Again, little change in the atmospheric conditions with PWATs remaining high around 1.7-1.9 inches with MLCAPE values around 1000-1500 J/kg with weak wind shear. Hi-res guidance favors convection along the sea breeze where best surface convergence will exist and expect scattered diurnal convection, similar to previous days. Severe threat remains low and feel the localized flooding threat is there also given slow storm movements in unorganized pulse convection. Temperatures will be near normal with highs in the lower 90s while overnight lows fall into the lower to mid 70s with some lingering debris clouds. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... Key Message(s): - Widespread showers and storms associated with an upper trough. Rain will likely be heavy at times with marginal risk of flash flooding. Tuesday, an upper trough will approach the area from the northwest with flow shifting out of the southwest, advecting significant deep layer moisture into the area from the Gulf. PWATs expected to increase over the course of the day with the HREF indicating a 50 to 60% probability of values greater than 2 inches. The strongest forcing will likely remain west of the area through much of the day with diurnally driven showers and storms developing in the anomalously moist airmass. As the trough shifts into the area Tuesday evening, showers and storms likely become more widespread with efficient rain rates as the NAEFS mean shows PWATs exceeding the 90th percentile across the area. Unlike previous days, forcing will allow convection to continue well after sunset and into the overnight period. Northwestern half of the forecast area remains in a marginal risk of excessive rainfall from WPC mainly due to the anomalously high PWATs and long, skinny CAPE profiles. Storms should be moving fast enough to limit any significant flooding problems, however. Overall severe risk remains low with moderate destabilization and limited organization as strongest deep layer shear remains well north of the area. With increased moisture and a breakdown of the ridge, expect highs a few degrees cooler, in the upper 80s to low 90s. The upper trough will continue to shift through the area during the day Wednesday which will continue to allow for waves of showers and storms that will diminish from west to east over the course of the day. WPC ERO extends the marginal risk for Wednesday through the rest of the forecast area with a similar synoptic setup and efficient rain rates expected to continue along with moderate destabilization, especially in the eastern portion of the forecast area. Cooler once again Wednesday with highs generally in the mid to upper 80s. Lows for both Tuesday and Wednesday in the low 70s. && .LONG TERM /THURSDAY THROUGH SUNDAY/... Key Message(s): - Near normal temperatures with isolated afternoon convection each day. More typical summer pattern returns through the extended period with heights recovering as temperatures return to normal with highs in the low to mid 90s and lows in the low to mid 70s. Northwest flow develops with ensemble means indicating upper ridging builds over the central US. This will lead to some drier air moving in aloft with PWATs also returning to near normal. As the axis of the upper ridge shifts into the area for the weekend, broad subsidence expected to return to the area which will overall suppress convection. Still chance for isolated storms, mainly favoring the sea breeze but blended guidance generally favors limited coverage of any convection that develops each day in the long term. && .AVIATION /07Z MONDAY THROUGH FRIDAY/... Generally VFR conditions expected through the forecast period outside of convection. Similar pattern continues over the area with weak upper ridging as the upper trough to our west becomes diffuse. Another round of afternoon and evening scattered convection which could result in temporary restrictions. Winds generally light from the south less than 5 mph through sunrise then picking up to 6 to 8 mph by afternoon. Convection should wane during the evening hours with some lingering debris clouds. Possible vsby restrictions in predawn fog but confidence is low. EXTENDED AVIATION OUTLOOK...Patchy ground fog possible each night...but is unlikely to cause significant issues at the terminals. A front will approach the Southeast Tue/Wed leading to increased thunderstorm chances. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...None. GA...None. && $$