Area Forecast Discussion
Issued by NWS Columbia, SC
Issued by NWS Columbia, SC
947 FXUS62 KCAE 040059 AFDCAE Area Forecast Discussion National Weather Service Columbia SC 859 PM EDT Sun Aug 3 2025 .SYNOPSIS... Wet weather is favored this week as a stalled boundary lingers across the region. Expect chances for rain and perhaps a few thunderstorms each day, especially across the southern Midlands and CSRA. Temperatures will remain below average, potentially warming towards the end of the week. && .NEAR TERM /UNTIL 7 AM MONDAY MORNING/... Key Message(s): - Cooler wedge conditions with showers continue this evening. - Shower coverage may diminish some overnight before increasing again Monday morning. The frontal boundary remains to our south with solid wedge conditions continuing this evening as high pressure in the Great Lakes region remains in place. Fairly moist flow is seen on top of this cooler surface airmass, driving scattered to numerous showers across the FA this evening, with the help of a weak perturbation in the upper flow. Overall rain rates have been on the light side, but there have been periods of moderate rain with rates up to around 0.75"/hr and localized spots of up to 1"/hr recently. This has lead to a widespread area of 0.25-0.75" of rainfall over the past 6 hours per MRMS analysis in the CSRA and into the central Midlands where spots upwards of 1-1.75" have been seen. A couple spots of nuisance flooding cannot be ruled out as soil moisture content is a bit higher in the CSRA and central Midlands. This batch of showers is expected to continue this evening before diminishing some during the early overnight with a small shot of dry air. Chances are expected to return rather early Monday morning in the southern FA as 300-310K Isentropic lift becomes a bit stronger and PWAT`s remain near to just under 2" here. This activity then is expected to slowly overspread the Midlands through the morning. && .SHORT TERM /7 AM MONDAY MORNING THROUGH TUESDAY NIGHT/... Key message(s): - Periods of showers likely through the period with areas of heavier rainfall possible, especially south and west of the Columbia area. - Temperatures remain below seasonal values, warmer in many locations on Tuesday as the wedge erodes. An upper trough will be centered over the Mississippi River Valley at the start of the period, sluggishly shifting eastward. As the trough approaches the FA, winds aloft should shift out of the southwest allowing PWATs to increase across the region. At the surface, a stalled boundary lingers across the area while high pressure over New England keeps wedge conditions in place on Monday, likely breaking down on Tuesday. Guidance remains divided on heavy rainfall potential but confidence in seeing 1-2 inches of precipitation through Tuesday Night is highest south and west of I-26, across the southwestern Midlands and CSRA. The GFS continues to offer a drier solution on Monday and Monday Night, showing little to no precipitation north and east of Columbia, while the Euro has widespread rainfall across the CWA. CAMs are favoring the GFS solution, suggesting that the wedge will hold for one more day before breaking down. Rain chances should be higher across the entire forecast area on Tuesday. Temperatures should remain well below normal on Monday, with warmer values possible on Tuesday, especially south and east of Columbia. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... Key message(s): - Diurnally driven showers and thunderstorms possible through the end of the week. - Temperatures could gradually warm through the extended. The upper trough continues its slow progression towards the region while weakening. Meanwhile, weak forcing over the CWA leads to more typical daytime convection Wednesday through Friday. Guidance remains at odds during the mid to late week period, and especially towards the weekend when the GFS suggests an area of low pressure will develop off the Southeastern US, potentially moving northwest towards North Carolina. For now, have maintained the NBM solution, which shows daily rain chances and gradually warming temperatures. However, things may be drastically different if the solution advertised in the GFS plays out, so forecast confidence is low during the extended period. && .AVIATION /01Z MONDAY THROUGH FRIDAY/... Showers on and off through the period. A combination of restrictions possible, depending on where the taf site is located. Surface front will remain off to the south of the forecast area tonight into Monday, with wedgelike conditions persisting over the region. Higher shower likelihood, along with lower ifr/mvfr ceilings and visibilities, will exist near ags/dnl closer to the surface front location. Most guidance is dropping those two locations into restrictions later tonight, then keeping then down for both ceilings and/or visibilities in rain through the period. Further north at cae/cub/ogb, higher likelihood of remaining vfr outside of light rain showers through the period, and this too is reflected in the latest guidance. Even in those locations though, periods of rain are expected to move across the area over the next 24 hours, with variability in ceilings remaining possible. Winds will remain out of the east to northeast through the period. EXTENDED AVIATION OUTLOOK...Periods of widespread restrictions and rain possible through the week. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...None. GA...None. && $$