


Area Forecast Discussion
Issued by NWS Charleston, SC
Issued by NWS Charleston, SC
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198 FXUS62 KCHS 292355 AFDCHS Area Forecast Discussion National Weather Service Charleston SC 755 PM EDT Sun Jun 29 2025 .SYNOPSIS... High pressure will extend across the region through early week. A cold front will then approach the area around the middle of the week, possibly stalling near the coast through late week. && .NEAR TERM /THROUGH MONDAY/... Isolated to scattered showers and thunderstorms should dissipate this evening, leading to a dry overnight for land areas. Some shower activity may develop over portions of the Atlantic waters late tonight. But no impacts to coastal areas are expected. Low temperatures are forecasted to range from near 70 degrees inland to the mid to upper 70s along the coast. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... Monday and Tuesday: Weak, broad low pressure will be present over the Southeast in the upper levels Monday and Tuesday. The area is also positioned along the western periphery of ridging in the mid levels, as well as surface high pressure fixed over the Atlantic, otherwise no real defined synoptic features will be present. Models show PWAT values approaching 2.0" each afternoon, which combined with sufficient instability will be supportive of convection each afternoon. Given the lack of large scale forcing thunderstorms will likely focus along the afternoon sea breeze and boundary interactions. The forecast features PoPs generally 40-60% each afternoon; the greatest chances across southeastern GA where the greatest moisture/instability is focused. Temperatures will be consistent with highs both days in the upper 80s/lower 90s, and min temps in the low to mid 70s. Wednesday: Ensemble guidance is in fairly good agreement that an upper level disturbance will cross New England with trailing vorticity all the way towards FL. As this occurs, a cold front will approach from the northwest Wednesday morning. Deep moisture noted by a slight surge in PWAts to around 2.2", combined with sufficient instability should support numerous to widespread showers and thunderstorms. Seasonable temperatures are forecast with highs in the upper 80s to low 90s. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... The aforementioned cold front shows signs of stalling over or near the forecast area just before reaching the coast Thursday. Although it appears the axis of deep moisture will nudge offshore Wednesday night, enough moisture will remain to support scattered showers and thunderstorms Thursday, especially with llvl convergence to focus convection near the front. The upper level disturbance will then eject off the Northeast coast Friday. As this occurs, a return to a more climatological summer pattern is forecast with a chance of showers and thunderstorms during the afternoons. However a lesser confidence, but potential scenario, is that a weak surface low forms along the remnants of the front near the end of the week, which could keep elevated rain chances through next weekend. Temperatures will remain in the low 90s through next weekend. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... 00Z TAFs: Mainly VFR. Convection may bring some impacts late in the TAF time period. But probabilities of this are low, so we only went with VC at this time. Extended Aviation Outlook: Brief flight restrictions are possible Monday and Tuesday afternoon during convection. Wednesday and Thursday, more widespread coverage of showers and thunderstorms are forecast as a cold front approaches from the northwest. This could provide more frequent periods of ceiling and visibility restrictions. && .MARINE... Tonight, the marine zones will remain between high pressure centered over the western Atlantic and broad trough across the middle Carolinas and GA. This pattern should yield southerly winds generally between 10-15 kts. Seas are forecast to range between 2 to 3 ft. Monday through Friday: High pressure over the Atlantic will prevail through the upcoming week, yielding south/southwest flow. Gusts along the coast could reach 20 knots each afternoon in association with the afternoon sea breeze. With the approach of a cold front mid week, winds could surge across the local waters Tuesday evening. Small Craft Advisories could be needed, especially across the Charleston County nearshore waters. Seas will build to 2-4 ft by Monday night and remain through the period. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...None. && $$ NEAR TERM... SHORT TERM...BRS LONG TERM...BRS AVIATION... MARINE...BRS