FXUS62 KMHX 060026 AFDMHX Area Forecast Discussion National Weather Service Newport/Morehead City NC 826 PM EDT Sun May 5 2024 .SYNOPSIS... High pressure will rebuild offshore while weak troughing continues across the Eastern Seaboard for the next few days, but warm moist southerly flow will lead to unsettled conditions. Drier but hotter conditions briefly expected Wednesday, before an approaching strong frontal system brings unsettled weather back to the area Thursday and Friday and potentially into the beginning of next weekend. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... As of 8 PM Sun...Shower and thunderstorm activity has been diminishing over the past couple of hours with loss of sfc heating. However, cannot rule out additional precip overnight with weak perturbations moving through flat ridging aloft ahead of an approaching shortwave. The best chance will once again be across coastal sections where nocturnal speed convergence could enhance precip chances. Evening update mainly captures PoP trends through the overnight. Previous discussion...Latest satellite and observational trends this afternoon show a messy picture across the Carolinas as a weak wave of low pressure ahead of a mid-level s/w trough migrates along a stalled frontal boundary draped across the NC Piedmont. Also of note is a weakening surface trough, which has proven to be a reliable focal point for showers through the day, now beginning to rotate back eastward as mean flow becomes southerly to southwesterly this afternoon. Airmass over the region is quite unstable with SPC mesoanalysis showing an uninhibited 1500-2000 J/kg SBCAPE pre-storm environment, although shear is severely lacking at 20 kt or less. Threat for showers and a few thunderstorms will continue into this evening, with the highest threat focused along the coastal plain where low-level convergence will be maximized. Isolated shower threat will continue along the coastal trough as it swings back eastward. Shear will remain very weak through the period and no severe risk is expected. Given long skinny CAPEs, locally heavy rainfall is possible in stronger storms but dry antecedent conditions preclude a flash flooding threat. Coverage will ebb tonight with loss of heating, but very muggy conditions will remain in place more in line with a summer-like pattern. A isolated showers remain possible inland, but modestly better coverage will be near the Crystal Coast and Outer Banks as nocturnal convective takes shape over the waters and threatens beach locales. Lows struggle to drop below the mid-60s inland, upper 60s along the water. && .SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/... As of 320 PM Sun...Cold front across eastern Canada this afternoon will gradually push south towards the mid-Atlantic tomorrow with increasingly southwesterly flow setting up across the Carolinas. Moist and unstable airmass will remain in place tomorrow and yet another round of showers and thunderstorms is anticipated. Coverage will be enhanced modestly as a stronger shortwave trough, currently over the lower MS Valley, lifts towards the region late tomorrow afternoon. Instability will not be a problem to come by, ranging from 1000-1500 J/kg, but a continued lack of shear will once again preclude an appreciable severe risk. Stronger shear associated with the s/w will work its way into the area in the early evening, but at this point activity will begin to wane with loss of heating and likely fail to utilize the more favorable winds. Convection will evolve in a classic summer pattern, with the first round along the seabreeze advancing inland and a second, decaying round as storms firing across central NC push towards the coastal plain. Highs will only be a couple degrees warmer than today, in the mid 80s inland and upper 70s to low 80s along the coast. && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... As 330 AM Sun...Unsettled weather will continue for the first half of the week as weak troughing lingers over the East Coast and warm moist southerly flow develops. By Wednesday drier conditions will briefly return but will be accompanied by an increase in heat and humidity. Then an approaching strong frontal system will bring unsettled weather back to the area late Thursday through Friday and possible into Saturday. Monday through Wednesday...Winds will veer to the SW Monday and Tuesday as high pressure rebuilds offshore. Despite this, a combination of weak troughing inland and deep moist southerly flow will bring fairly unsettled conditions through Tuesday. Showers and convection will be diurnally enhanced and will target the NC coastal plain. Temperatures will be in the upper 70s to low 80s Monday, and the low to mid 80s Tuesday. Drier conditions are briefly expected Wednesday as upper level riding builds back over the Southeast. Increasing low level thicknesses and continued SW flow will result in hot and humid conditions with afternoon highs reaching the upper 80s to low 90s inland, and low to mid 80s along the coast. Thursday through Saturday...Weak upper level troughing will again redevelop overhead Thursday with a large trough looming across the Great Lakes. This will bring a more conducive environment for afternoon/evening shower and thunderstorm development with hot and humid conditions expected again. However, questions remain about the quickness with which troughing will develop locally and have will limit precip chances to around 50% at this time range. A robust shortwave trough will swing southward into the area on Friday with a surface cold front also surging south from the Mid-Atlantic. Ahead of this front a moist and unstable airmass will persist, and the initial impression of this weather pattern indicates severe weather will be possible, with potential for a significant event if all ingredients come together. That being said, much can change at this time scale but we will continue to monitor this potential. The front will push through the area sometime Friday night or early Saturday, with mostly dry conditions expected by Saturday. A more seasonable airmass will move in behind the front with highs near to just below normal. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... SHORT TERM /through 18z Mon/... As of 8 PM Sun...Showers/storms diminishing this evening with loss of heating with VFR conditions across rtes. Expect MVFR cigs to develop late tonight, around 06-07z, across most areas with greatest chances inland from the coast. HREF probs show 50-70% chance of IFR across far inland rtes after 08z and have included at PGV and ISO. Cigs gradually lift through Monday morning with pred VFR expected to return mid to late morning. A moist and unstable airmass remain in place Monday and expect scattered to numerous showers/storms to develop during the afternoon bringing periods of sub-VFR conditions with greatest coverage expected along the sea breeze. LONG TERM /Monday night through Thursday/... As of 330 AM Sun...Generally VFR conditions are expected through mid next week, however unsettled conditions every day except Wednesday could lead to moments of sub-VFR conditions each afternoon/evening. && .MARINE... SHORT TERM /through Monday/... As of 330 PM Sun...Benign boating conditions in place for the waters this afternoon, outside of increasingly isolated shower activity along a coastal trough draped across the western Pamlico Sound, forecast to drift eastward through the period. Regional observations show southerly winds of around 10-15 kt with seas around 3-4 feet. These conditions will change little through Monday, with winds gradually veering southwesterly as cold front approaches from the north and winds increasing modestly in the evening with a tightening thermal gradient. Convective coverage increases modestly especially across Onslow and Raleigh Bays after midnight, then waning mid to late morning on Monday. LONG TERM /Monday night through Thursday/... As of 330 AM Sun...Decent boating conditions will continue early this week. Worsening conditions are expected by mid week with Small Craft conditions likely developing across portions of the coastal waters. Winds Monday night will generally be SW 10-15 kts, and then increase to 15-20 kts Tuesday. By Tuesday night, winds will strengthen slightly more, which will lead to occasional 25 kt gusts across the coastal waters through Wednesday. SW winds will increase further Thursday as the gradient increaes ahead of a cold front, and SW winds will become 20-30 kts. Seas will be mostly 2-4 ft through Tuesday morning, and will then increase to 3-5 ft. Late Tuesday night some 6 foot seas will develop across portions of the coastal waters through Wednesday. Seas will increase to 5-7 ft Thursday in response to strengthening winds. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...None. MARINE...None. && $$ SYNOPSIS...MHX NEAR TERM...SK/MS SHORT TERM...MS LONG TERM...SGK AVIATION...SK/SGK/MS MARINE...SGK/MS