


Area Forecast Discussion
Issued by NWS Columbia, SC
Issued by NWS Columbia, SC
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275 FXUS62 KCAE 012356 AFDCAE Area Forecast Discussion National Weather Service Columbia SC 756 PM EDT Tue Jul 1 2025 .SYNOPSIS... A weak front approaches the region leading to increasing rain and thunderstorm chances through Wednesday. Rainfall may be heavy at times and could lead to localized flooding mainly in flood prone areas. Drier air works into the forecast area from the north and west for the latter portion of the week limiting thunderstorm coverage with highest chances towards the coast. Isolated to scattered showers possible this weekend as low pressure potentially develops along the remnant frontal boundary. && .NEAR TERM /UNTIL 7 AM WEDNESDAY MORNING/... Key Message(s): - An approaching front will bring showers and storms across the area this evening. Not too much change in the forecast thinking for this afternoon and evening with an approaching trough and weak surface front nearing the area. Abundant low-deep layer moisture has pushed PWAT`s back to around 2.0" and surface dew points have held steady in the low-mid 70`s. Despite the approaching front, mid-level lapse rates will remain fairly mediocre and surface heating will not be terribly impressive either, yielding a modest ML CAPE environment in the HREF suite (around 1000 J/kg). Again, despite an approaching trough, there is only weak mid-deep layer winds associated with it and therefore only modest shear. The HREF has been consistent in producing widespread showers and storms this evening, which lines up nicely with this type of modest forcing, modest CAPE, and high moisture environment. Severe threat will remain highly isolated given the lack of shear and weak downdraft potential with a lack of DCAPE and dry air aloft. Some boundary collisions or cell mergers could pop a severe storm however. Heavy rain potential is present with these storms, but storm motion should preclude much flash flooding threat. But like with severe, the threat should be isolated but cannot rule out a few areas of flash flooding given the high PWAT`s and efficient instability profiles. Convection is expected to linger into the evening hours particularly across the western part of the area as the frontal boundary approaches from the west but intensity should wane by late evening. Widespread cloud cover overnight should limit radiational cooling and expect lows to be in the lower 70s. && .SHORT TERM /7 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... Key Message(s): - Widespread showers and storms - Localized flash flood risk mainly in flood prone areas An upper trough will shift into the eastern US on Wednesday. The associated cold front will sag into the Southeast providing surface convergence to aid in convective initiation during the afternoon. PWATs above 2 inches, low level convergence, and weak synoptic support will promote widespread showers and storms during the afternoon. Heavy rain will be possible given the above normal atmospheric moisture and weak to moderate instability in tall, skinny CAPE profiles. Although widespread flash flooding appears unlikely due to storm motion values around 10 kts, we may still see localized flash flooding, mainly in urban areas and other flood prone locations. With widespread rain expected, temperatures should be a bit cooler Wednesday with highs in the mid to upper 80s. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Key Message(s): - Drier air enters the region from the north and west A weak frontal boundary will settle across the Southeast during the latter portion of the week. With drier air impinging on the FA behind the front we will see lower rain chances from Thursday to Saturday compared to Wednesday. Depending on where the front settles, storm chances may be limited to the eastern half of the FA with higher rain chances near the coast. This weekend some ensemble members indicate potential for low pressure to develop along the remnants of the old frontal boundary. If this occurs that may draw moisture back into the region depending on the location of development. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... Low End Risk for a Passing Shower or Thunderstorm this Evening.... Thunderstorms have struggled to develop today across the forecast area. One line of decaying convection is approaching AGS/DNL with a second cluster approaching OGB. Have added a TEMPO for thunderstorms during the next few hours at these sites while keeping VCSH at CAE/CUB on the off chance something develops there before nightfall. Much of the overnight period is expected to be quiet as any lingering convection quickly diminishes with the loss of daytime heating. Guidance is once again hinting at the potential for low ceilings tomorrow morning so opted for mainly a persistence forecast at all terminals with a TEMPO for LIFR at DNL where decks were the lowest this morning. Ceilings should improve around midday giving way to scattered cumulus and eventually the threat for showers and thunderstorms in the afternoon. Leaving thunder chances out of the TAFs for now due to lower confidence. Probabilities for thunder in the afternoon will likely be highest at OGB. EXTENDED AVIATION OUTLOOK... Patchy low clouds and/or ground fog possible each night along with diurnally favored showers and thunderstorms. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...None. GA...None. && $$