Area Forecast Discussion
Issued by NWS Columbia, SC
Issued by NWS Columbia, SC
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116 FXUS62 KCAE 151702 AFDCAE Area Forecast Discussion National Weather Service Columbia SC 102 PM EDT Wed May 15 2024 .SYNOPSIS... Showers and thunderstorms will be possible again this afternoon, with isolated strong to severe storms. Upper ridging will provide a brief break in the unsettled conditions on Thursday. Shower and thunderstorms chances increase again Friday and especially on Saturday with unsettled weather lingering into early next week. Ridging builds in during the middle of next week resulting in decreasing rain chances and a gradual increase in temperatures. && .NEAR TERM /THROUGH TONIGHT/... Low clouds have cleared or lifted quickly across the forecast area as daytime heating has begun. Temps have been raised over the next several hours as we were running a bit low and I expect mid to upper 80s for the majority of those along and south of I-20 this afternoon. The real weather maker is expected to push into the region over the next several hours. A robust shortwave, noted in satellite imagery, continues to push southeastward from southern TN this morning. Ahead of this, warm and moist low-levels are expected to help yield moderate instability (~1000-1500 j/kg of CAPE) across much of the area, especially as mid-level temps cool on the approach of the shortwave. Shear looks relatively weak, but sufficient for organized multi-cell clusters this afternoon. Guidance has been a bit slow to initiate convection with recent events, and this event looks no different. Raised PoPs beginning at 18z because the shortwave is going to approach the area around this time, with convection increasing in coverage thereafter. As it pertains to severe weather, instability will be more than sufficient and shear will be merely sufficient. Looking at DESI mean soundings, westerly storm relative shear favors hailers, but mid-level moisture looks to increase in coincidence with improving forcing through the afternoon. But low-level look to dry a bit, which would help as well and should help promote near severe downdrafts. So overall, the slight risk for the northern and northeastern FA is reasonable, with strong to marginally severe storms (max threats of 0.75"-1.25" hail, 55-65 mph wind gusts) possible through the afternoon hours. PREVIOUS DISCUSSION: Tonight, any lingering convection should wane and shift to the Coastal Plain by midnight with drier air and high pressure building into the area behind a weak cold front. Clearing skies overnight should favor radiational cooling and expect overnight lows slightly cooler than tonight with lows in the upper 50s to lower 60s. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... Thursday and Thursday Night: Drier weather will return back into the area as an upper ridge builds in from the west. Should see much more sunshine through the day as a west-northwesterly wind pattern brings some downsloping across the cwa. This should also have the affect of bringing temperatures back into the low to mid 80s for afternoon highs. Overnight lows will be mild in the low to mid 60s. Friday and Friday Night: The upper ridge begins to move east through the day in response to an upper level low moving out of the Southern Plains. Moisture will once again be on the increase, so even though the day will start off dry, the region should see the development of isolated to scattered showers or thunderstorms during the afternoon. Better rainfall chances should occur Friday night as the deeper trough moves towards the region. Temperatures for the afternoon will reach the low to mid 80s. With the expected increase in clouds, overnight lows in the mid to upper 60s. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... Some uncertainty exists Saturday due to timing differences with the models. Even if there are some timing issues, at some point Saturday there should be numerous showers and/or thunderstorms across the entire cwa. NBM shows likely to categorical pops for much of the day, and will not really stray much from those numbers. Sunday will see the upper low eventually moving through and east of the cwa, and should see some shower activity early in the day before some drying becomes possible during the afternoon and evening. Behind the low, drier air returns and will bring dry conditions then from Sunday night through Wednesday. Temperatures next week rise back above normal. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... VFR conditions generally expected through the forecast period outside of some early morning fog/stratus. Overnight convection has dissipated and fog and stratus has also dissipated or shifted away from the terminals. However, satellite imagery showing some stratus moving northward through GA which may impact AGS/DNL so included a tempo group through 15z and also at OGB where some stratus is still lingering nearby. Light southerly winds pick up to around 10 knots by 15z from the southwest with gusts to 20 knots through the afternoon. Isolated afternoon convection possible as the upper trough moves through the region but coverage not high enough to include in this forecast. EXTENDED AVIATION OUTLOOK...Showers and thunderstorms and associated restrictions are possible again Friday and Saturday. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...None. GA...None. && $$