Area Forecast Discussion
Issued by NWS Columbia, SC
Issued by NWS Columbia, SC
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184 FXUS62 KCAE 021045 AFDCAE Area Forecast Discussion National Weather Service Columbia SC 645 AM EDT Sun Jun 2 2024 .SYNOPSIS... Moisture continues to increase over the region through early to mid next week. This will lead to isolated to scattered convection mainly in the afternoons and evenings. A cold front approaches the Southeast late next week leading to increasing rain chances. Temperatures should rise to near normal values over the next few days. && .NEAR TERM /THROUGH TONIGHT/... Satellite imagery shows that clouds have generally spread across almost the entire forecast area. Upper air analysis indicates that the axis of a shortwave trough is moving through Tennessee and Georgia this morning with another shortwave behind it near the Alabama and Mississippi border. Radar continues to show some light rain showers across the Southeast, though not sure exactly how much of this activity is hitting the ground. Have only seen a few of stations in and around the area showing rain hitting the ground. Today and Tonight: Upper shortwaves are expected to continue translating eastward through the day, bringing the chances for showers and potentially thunderstorms along with them. As a result, we should see isolated to scattered showers and storms peaking in coverage this afternoon into early evening time frame before diminishing overnight. The highest coverage of activity is favored for the western Midlands and Upper CSRA. There does not appear to be much of a severe threat today with any storms that form as both instability and especially spear are forecast to be lacking. For example, the HREF mean surface based CAPE is around 500 J/kg with around 15 kts of 0-6 km shear. As daytime heating wanes overnight, the chances for precipitation decrease as well. Temperatures are forecast to be similar, or just a tad cooler than yesterday, with highs in the lower 80s for most. Overnight lows are likely to remain in the mid 60s once again. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... Monday and Monday night...Long wave upper trough will extend from the Mid Atlantic south through the Carolinas early in the day then shift to the coast in the afternoon. The Bermuda high will be offshore with weak south- westerly flow across the area. The moisture appears to decrease somewhat through the day with the higher precipitable water shifting to the east. Models suggest relatively weak to moderate instability instability in the afternoon as temperatures rise into the mid to upper 80s with warm advection. Relatively steep low to mid level lapse rates noted with inverted V sounding profile. Mid level lapse rates are weak and there may be a developing cap in the afternoon as trough moves toward the coast. The ECMWF does show a short wave moving through the area and the GEM shows a weaker one. The lift appears focused in the Pee Dee. Perhaps a sea breeze front may move inland during the afternoon to provide lift. The CAMS show limited convective coverage...i.e., widely scattered. NBM focus pops in the east. Cut pops back slightly from NBM, but expect some isolated showers in the morning then scattered showers/thunderstorms mainly in the afternoon mainly in the east. Any convection should diminish quickly in the early eventing. Lows near normal values in the mid to upper 60s. Tuesday and Tuesday night...Mid level ridge appears stronger Tuesday and instability appears weaker than Monday although low to mid level lapse rates appear steep given temperatures continue to climb to around 90 degrees with continued warm advection. Think there may be a strong cap. Moisture decreases as well with precipitable water down to 1.3 inches. Trigger lacking although another sea breeze front is possible. Cut pops to slight chance most areas in the afternoon with chance along the 95 corridor. Low temps a little warmer, mainly upper 60s. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... Ensemble models have been consistent. Upper level ridge flattens early in the period and shifts east. Moisture increases again across the region especially by Thursday with models indicating high probability of values > 1.5 inches, possibly near 2 inches. Deep upper low over south central Canada will be building southeast with generally northwest flow across the southeast. Embedded short wave troughs will be moving through the area as trough develops in the southeast. At the surface, a cold front is expected from the Ohio Valley southwest to the mid Mississippi valley in the day Thursday. The front will be moving toward the southeast late week, moving into the area Friday. Scattered convection expected Wednesday and Thursday. Ensembles indicating chance of moderate instability with increasing triggers for thunderstorms. Deep layer shear becomes moderately strong by Thursday as the front approaches from the northwest. Stronger lift possible with diffluent flow aloft. So, at this time marginal severe threat. Drier air moving in by Saturday. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... VFR conditions expected through the TAF period. Extensive cloud cover remains over the region with a few light showers heading into the Midlands from the Southwest. However, restrictions have yet to be recorded and don`t expect vis to go much below 10SM. if at all. So have included VCSH at CUB and CAE through 15z to account for this activity. After this wave of activity passes, additional chances for showers and a few thunderstorms are possible once again this afternoon and evening. Have included VCSH at CUB/CAE/AGS/DNL to account for this, but more fine tuning will likely be needed in future updates. Winds are expected to generally become southerly less than 10 kts through the TAF period. EXTENDED AVIATION OUTLOOK...Isolated afternoon and evening showers and thunderstorms Monday through Thursday with intermittent CIG/VSBY restrictions possible. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...None. GA...None. && $$