106 FXUS62 KILM 160726 AFDILM Area Forecast Discussion National Weather Service Wilmington NC 326 AM EDT Thu May 16 2024 .SYNOPSIS... High pressure should bring dry weather today with pleasant temperatures. Rain chances will increase again this weekend as a new storm system advances eastward across the Southeast. As the low exits the Carolina coast Sunday, a cold front will push offshore bringing below normal temperatures Monday and Tuesday. && .NEAR TERM /THROUGH TONIGHT/... Widespread low stratus deck currently across most of southeast NC is expected to extend south into parts of the Pee Dee region over the next few hours. This low cloud deck may be stubborn during the morning and linger for a few hours past sunrise as winds remain light and minimal drying present below 700mb and thus how expansive/thick the stratus is will dictate how long it will take for the May sunshine to mix it out. After the low clouds dissipate, some afternoon diurnal cumulus will develop with high temps around 80-83F. There is a chance for an isolated storm along pinned sea breeze this afternoon, with light NW winds inland aiding convergence, and have included 15-20% pops across parts of Horry, Brunswick, and New Hanover counties. Ridge moves overhead tonight with clear skies and light winds allowing temps to drop to low-mid 60s. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... A shortwave ridge will move eastward across the coastal Carolinas Friday morning. Surface high pressure centered just downstream of this ridge will accompany it offshore, allowing southerly flow to develop during the day. The ridge's capping subsidence inversion will decay as mid level temps cool with the approach of an upper disturbance from the southwest. All this should allow scattered showers and thunderstorms to develop across South Carolina during the afternoon, pushing east to the coast Friday night. For the past several days models have had little, if any, consistency with their depictions of the upper level pattern and sensible weather this weekend. Over the past 24 hours broad consensus has begun to emerge and confidence is finally beginning to increase. A moderate-strength shortwave over the southern Mississippi Valley Saturday morning should slowly shift east toward the southern Appalachians by late Saturday night. Deep southerly flow from the Gulf will lead to both isentropic lift plus convective instability across the Carolinas, helping to develop widespread showers and embedded thunderstorms. Surface low pressure will develop early Saturday across the Mid South and should discontinuously move eastward, modulated by convective activity, until it reaches the Carolina coast after midnight. Over an inch of rain is forecast with higher amounts likely where convective training occurs. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... Model consensus has begun to increase for early next week, although it's in a different way than what was expected just 24 hours ago. An elongated area of surface low pressure should extend across the eastern Carolinas and offshore Sunday. As an upper level disturbance across the southern Appalachians moves eastward, it should help consolidate the low fully offshore, dragging a significant cold front southward across the area. Lift across this initially shallow front should lead to another round of significant rain and thunderstorms Sunday afternoon and evening, finally tapering off as the upper disturbance moves offshore. Although this is beyond our official rainfall amount forecasts, indications are a widespread half inch could occur with embedded higher amounts. Upper level ridging developing across the Great Lakes and New England will build north of our offshore disturbance Monday into Tuesday, leading to the disturbance either slowing appreciably or cutting off entirely. This may occur close enough to the Carolinas to provide one or two days of unseasonably cool northerly winds with coastal clouds and showers. I've trimmed back forecast highs significantly both days, although not quite as steeply as the 00z model consensus would indicate to maintain better continuity with our neighboring NWS office forecasts. Highs on Monday may have trouble rising much beyond the mid 70s. By Wednesday a shortwave moving eastward across Canada should erode the upper ridge to our north, allowing the captured shortwave off the Carolina coast to begin to progress eastward again. Assuming this occurs, we'll finally break back out into sun and seasonably warm temperatures. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... LIFR stratus deck around 300-400 ft has developed across most of southeast NC, including KILM and KLBT. With abundant low level moisture available, in part due to Wednesday's storms, look for this stratus deck to continue expanding southward. Have low clouds moving into KFLo around 8-9z. Confidence is less along coastal NE SC (i.e., CRE and MYR) where this is a lower chance of the stratus deck making it that far. Have still included TEMPO groups for both, mainly for lower vsbys. With light winds and minimal low level drying, morning stratus may be a bit stubborn after daybreak and take a few hours to burn off. After the stratus dissipates (perhaps 14-16z), look for some diurnal cumulus to develop with an isolated storm possible along pinned sea breeze in the afternoon. Winds remain fairly light throughout TAF period. Extended Outlook...VFR conditions to dominate Thursday night through Friday. The next system with potential periodic flight restrictions will affect the area this weekend into Monday. && .MARINE... Through Tonight...Conditions will continue to improve across the local coastal waters with earlier storms far offshore and surface ridging building in from the west during the day. Seas 3-4 ft at daybreak this morning will lower to 2-3 ft this afternoon and around 2 ft tonight, combination of quickly weakening S swell and a 1 ft E swell. Light offshore winds early today will turn southeasterly with sea breeze this afternoon. Friday through Monday...Light and variable winds Friday morning beneath high pressure will become southerly by afternoon as the high shifts offshore. Low pressure should gradually take shape across the Mid South Friday night, expanding eastward on Saturday. For the past several days weather models displayed an unusually large spread in possible outcomes for this weekend into early next week. While we're still far from certain, this morning's new model runs are converging on the idea that low pressure will move eastward across the Carolinas on Saturday and Saturday night developing widespread rain and thunderstorms. The low will move offshore late Sunday, dragging a cold front southward across the the area. A sizable pressure difference should develop between the offshore low and the colder air inland and Small Craft Advisory conditions in winds and seas may develop Monday. This general scenario is now shown by the 00z runs of the GFS, Canadian, and ECMWF models. && .ILM WATCHES/WARNINGS/ADVISORIES... NC...None. SC...None. MARINE...None. && $$ SYNOPSIS...TRA NEAR TERM...VAO SHORT TERM...TRA LONG TERM...TRA AVIATION...VAO MARINE...TRA/VAO