Area Forecast Discussion
Issued by NWS Columbia, SC
Issued by NWS Columbia, SC
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866 FXUS62 KCAE 110527 AFDCAE Area Forecast Discussion National Weather Service Columbia SC 127 AM EDT Sat May 11 2024 .SYNOPSIS... High pressure keeps the area dry through the weekend and into the beginning of next week. The high moves offshore Monday and increasing moisture supports showers and thunderstorms returning for next week. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... Remaining convection has moved east of the forecast area and severe thunderstorms 231 has been cancelled. Cooler and drier air has already begun to enter the area with dewpoints falling into the mid to upper 50s at many locations along and north of I-20. Although there is plenty of low level moisture to consider stratus and fog with winds turning northerly overnight and remaining 5 to 10 mph coupled with drier air moving into the region do not expect any fog or stratus to develop. The northerly winds will also be advecting in cooler air and combined with the clear skies overnight lows will drop into the low to mid 50s. && .SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY NIGHT/... A much deserved break in the weather is expected this weekend as troughing, upper level convergence, and surface high pressure settle into the region. Guidance is in wonderful agreement in the forecast for Saturday and Sunday. Partly cloudy skies are expected on Saturday as a reinforcing shortwave dives through the Mid-Atlantic, with highs in the upper 70s. Lows will be in the 50s under clear skies Saturday night. Sunday should be a bit warmer with some downslope flow expected as high pressure shifts through the area. Highs should be in the 80s with lows in the upper 50s. && .LONG TERM /MONDAY THROUGH FRIDAY/... Fairly high confidence in the pattern that is expected to unfold next week. A progressive and meridional pattern is shown by LREF members by Monday and this should take us through the end of next week. Slow, lowish amplitude upper level trough is expected to be centered across the central Plains by Monday morning, with a ridge axis shifting across our FA through the day. Surface high pressure should still be in place but is expected to shift offshore by Monday night, with moisture and isentropic lift increasing through the day. Rain is likely by Monday night, with each group of ensembles in the LREF showing ~70-80% of members with rain chances by Monday night. Surface low should slowly push eastward on Tuesday, settling over the OH Valley. Strong westerly and southwesterly flow is shown by both operational models and LREF members. While operational models are unsure about convective potential, the overall synoptic setup is one that tends to favor at least thunderstorms across the FA. LREF members generally show decent probabilities (25-40%) of sufficient CAPE and shear to support potential strong storms. So we`ll need to keep a close eye on model trends over the next couple of days. Rain chances look to peak Tuesday evening, with the trough axis shifting the best lift and surface low to our east on Wednesday. The break looks short, though, as another shortwave is expected to dig into the south-central Plains. A ridge axis will likely settle in over the region by Wed/Thur, with significant uncertainty regarding the pattern thereafter emerging. The shortwave trough that digs into the southern plains looks like it could be significant, but timing and amplitude issues abound amongst LREF members and operational models. For now, will keep the NBM as is given the significant uncertainty in the long term. Temps should be seasonal or slightly below normal in this period given the repeated shots of rain and potential cloud coverage. Highs will likely be in the upper 70s to mid 80s with lows in the 60s. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... VFR conditions expected through the TAF period. High pressure moving into the region is providing clear skies to the area. Skies are expected to remain mainly clear through the TAF period, with the exception of some fair weather cumulus during the afternoon hours. Light and variable winds become north to northeast between 5 and 10 kts, then shift to more westerly after about 17z. Dry conditions and a low level jet should hinder any fog development. EXTENDED AVIATION OUTLOOK...Showers and thunderstorms and associated restrictions are possible Monday through Wednesday. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...None. GA...None. && $$