Area Forecast Discussion
Issued by NWS Columbia, SC
Issued by NWS Columbia, SC
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573 FXUS62 KCAE 110703 AFDCAE Area Forecast Discussion National Weather Service Columbia SC 303 AM EDT Sun Aug 11 2024 .SYNOPSIS... Hot temperatures and high humidity are likely to lead to triple digit heat indices again today. Scattered afternoon and evening thunderstorms are also likely this afternoon. River flooding is expected to continue over the next several days. Temperatures then cool off slightly early this week with daily chances of afternoon showers and thunderstorms continuing. && .NEAR TERM /UNTIL 7 AM SUNDAY MORNING/... Key Message(s): - Patchy fog possible around daybreak Storms should diminish in coverage and intensity by midnight at the latest, with clouds likely diminishing thereafter as well. Lows tonight are expected to be in the mid 70s. && .SHORT TERM /7 AM SUNDAY MORNING THROUGH MONDAY NIGHT/... Key Message(s): - Isolated flash flooding and severe storm potential on Sunday, with decreasing risk on Monday The upper level pattern will be relatively zonal through the start of the week with a weak and diffuse surface boundary stalled across the area. This will raise a couple concerns as instability will be moderate to strong with CAPE in excess of 2000 J/Kg and DCAPE values around 1000 J/Kg. Pwat values will also remain in the 1.9 to 2.2 inch range and when combined with the surface boundary expect mainly diurnal showers and thunderstorms to develop each day. Pops will range from chance in the western Midlands to likely in the eastern Midlands with the concerns focusing on potential for strong and gusty winds along with locally heavy rainfall. The forecast area is covered by a SPC general thunder each day with WPC having a slight risk of excessive rainfall across much of the area Sunday and a marginal for Monday. With soils nearly saturated from recent rainfall expect any heavy rainfall to have the potential to result in localized flooding...especially in the eastern Midlands where the greatest amount of rain occurred. High temperatures each day will range from the upper 80s along the NC border to the mid 90s in the CSRA. Overnight lows will be in the low to mid 70s. && .LONG TERM /TUESDAY THROUGH SATURDAY/... Key Message(s): - A more typical summer pattern through next week with afternoon showers and thunderstorms The upper level pattern will become more amplified through the long term with ridging building over the central US and a trough over the eastern US. This will keep the area under typical summertime conditions with chances of mainly afternoon and evening showers and thunderstorms. The chances of convection will mainly be controlled by upstream convection, short waves and MCSs which could move into the area leading to some increased chances or nocturnal convection. With the trough over the eastern US temperatures should be slightly below to near normal through Saturday. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... IFR/LIFR conditions possible early this morning in fog and stratus, especially near the CAE/CUB/OGB terminals. Expect mainly mid and high level clouds this morning, with near calm winds. However, persistent low-level moisture across the area and clearing aloft over the next several hours will lead to some fog and stratus concerns toward sunrise. Fog and stratus may be slow to erode, but by 11/16z expect VFR conditions with scattered cumulus at 4-6k ft MSL. The air mass should become moderately to strongly unstable in the afternoon, with scattered thunderstorms expected after 11/18z. Confidence is still a bit low for TEMPO groups at the terminals, so used VCSH for now. Winds generally light and variable increasing S/SE this afternoon around 8 kts or less. Thunderstorms may produce erratic and gusty winds to 40 kts. Convection clears late this evening with winds returning to light and variable. EXTENDED AVIATION OUTLOOK...Afternoon and evening convection and associate restrictions will be possible through Thursday. Early morning fog and stratus could occur, especially at fog- prone AGS/OGB. && .HYDROLOGY... Key Message(s): - Area rivers have crested and are falling. The Pee Dee at Cheraw and the Wateree River at Camden are currently at moderate flooding levels, but will fall into the minor category shortly. Minor flooding will continue on the Congaree River south of Columbia in the Congaree National Park through tomorrow morning. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...None. GA...None. && $$