Area Forecast Discussion
Issued by NWS Columbia, SC
Issued by NWS Columbia, SC
985 FXUS62 KCAE 141026 AFDCAE Area Forecast Discussion National Weather Service Columbia SC 626 AM EDT Sat Jun 14 2025 .SYNOPSIS... An active weather pattern continues this weekend with widespread showers and thunderstorms expected each day. Ridging builds into the region next week which will lead to warming temperatures and a more typical summertime pattern of scattered thunderstorms. Heat Index values may exceed 100 degrees in the long term. && .NEAR TERM /THROUGH TONIGHT/... Key Message(s): - Scattered to widespread shower/storm chances continue to start the weekend. - Heat indices up to around 100F are expected this afternoon. Some scattered convection is on going early this morning mainly in the eastern Midlands with some elevated instability remaining and PWAT`s around 2.1-2.2" across the whole FA. This activity likely continues through sunrise before a brief break maybe seen through the mid to late morning, allowing instability to build again with deep moisture remaining in place as southerly to southwesterly moisture transport continues. The synoptic picture does not change much through the day with the region remaining in between the subtropical high offshore and upper trough that is now entering the Mississippi Valley. This trough will near closer through the afternoon and evening, possibly sending some shortwave energy toward the region. The maintenance of southwesterly to southerly flow will bring temperatures back into the upper 80s to low 90s and with the very humid airmass in place, heat indices peaking near 100-102F are expected during peak heating in the afternoon. Scattered to widespread summertime diurnal convection once again is expected during the afternoon and evening in a modestly to strongly unstable environment, where an isolated strong to marginally severe storm cannot be ruled out with the primary hazards of damaging winds, heavy rainfall, and frequent lightning. As was realized near the Columbia Metro and toward Sumter County last evening, where the interaction of mesoscale boundaries occur, training slow moving thunderstorms could bring localized flash flood situations with multiple inches of rain falling in a couple hours. Where these potential interactions occur will be the main item of interest as we keep deep moisture and very efficient rainfall rates in these storms this afternoon and evening. Similar to the past couple of nights, some of this activity may carry into the overnight period with the moist airmass in place and lows that only fall into the low 70s. && .SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/... Key Message(s): - Isolated damaging winds possible in the afternoon High pressure slides to our south on Sunday promoting a more westerly flow pattern with slightly lower PWAT values than the previous few days. Lee side troughing in the wake of the Appalachians and a sea-breeze will trigger convection in the afternoon as the air mass destabilizes. Although instability will be weak to moderate, steep low level lapse rates may allow for a downburst wind threat. A shortwave may also pass to our north on Sunday afternoon supporting convective development although the stronger PVA may be in NC. CAMs show limited coverage however they have consistently been underdone the past few days. With PWAT values ranging from 1.75 to 2 inches the heavy rain threat is a little lower than the previous few days. Highs will be in the upper 80s to low 90s. Lower dewpoints should keep max Heat Index values in the 97 to 102 degree F range. && .LONG TERM /MONDAY THROUGH FRIDAY/... Key Message(s): - Seasonable weather with daily thunderstorm chances - Heat index values approaching or exceeding 100F next week Next week, the ridge off of the Southeast Coast will build west leading to height rises over the forecast area mid-week. The NAEFS shows that heights over the FA are not exceptionally anomalous but will still favor temps a few degrees above normal. Afternoon highs will warm into the lower-mid 90s each afternoon of the long term. Overnight lows will also be a few degrees above normal with values in the low to mid 70s. PWAT values will return to near normal values by mid-week. Ridging over the region and near normal atmospheric moisture will support traditional summertime conditions with isolated to scattered convection each afternoon. && .AVIATION /10Z SATURDAY THROUGH WEDNESDAY/... Periods of MVFR to IFR restrictions being seen at all sites this morning and should continue before 14-15z. More restrictions are possible this afternoon and evening with convection. A stray shower is moving away from CAE/CUB this morning as some stratus is seen developing with periods of SCT to BKN ceilings at all sites. Most of the TAF sites have solidly been in MVFR conditions but periods of IFR have been seen and are expected to continue before 14-15z. Ceilings then gradually rise to VFR with SCT cumulus and high clouds expected. Winds today look to be out of the southwest to south at 8-11 kts with some isolated gusts toward 15-18 kts possible this afternoon. More scattered to widespread afternoon/evening showers and storms are expected after 16-18z where intermittent restrictions will be possible at each terminal. Some of this activity may linger toward into the early overnight period but at this time, there is low confidence in any possible restrictions overnight due to showers/storms. Despite lingering moisture, model guidance has not been overly impressed with any stratus development tonight and thus I have opted to leave mention of this out at this time, though some brief MVFR ceilings/visibilities are not out of the question. EXTENDED AVIATION OUTLOOK...Brief restrictions are possible each afternoon/evening into early next week with typical summertime convection. Patchy early morning fog and stratus may also cause some restrictions. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...None. GA...None. && $$