Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC

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295 FXUS62 KRAH 091433 AFDRAH Area Forecast Discussion National Weather Service Raleigh NC 1030 AM EDT Fri May 9 2025 .SYNOPSIS...
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A cold front will move south across NC this evening. A couple of areas of high pressure will follow and build from the Great Lakes to the Middle Atlantic and Carolinas through the weekend. A slow moving low pressure system will bring unsettled weather early next week.
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&& .NEAR TERM /THROUGH TONIGHT/...
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As of 1030 AM Friday... The precip has exited the area, with clearing skies taking over this morning. A few low to mid clouds are lingering along a boundary across portions of the SW Piedmont and western portions of the Sandhills. Looking a the Mid-Atlantic View of Satellite, you can clearly see the cold front that will move into Central NC later this evening and overnight. As its shifts across the region itll bring another chance of showers and storms. The atmosphere does not have much energy left after the storms from last night so expect less severe weather including damaging winds and small hail. The best chance for precip will be in the northeastern Piedmont early this afternoon and spreading south into the Sandhills and Coastal Plain late this afternoon/early evening. While the NW Piedmont has PoPs of 20% or less, an isolated shower or storm cannot be ruled out. Highs this afternoon will be in the mid 70s north, to low 80s south ahead of the front. As the frontal boundary exits the area sometime after sunset and before midnight, expect cooler drier air to filter in with overnight lows in the upper 40s north, to upper 50s south.
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&& .SHORT TERM /SATURDAY AND SATURDAY NIGHT/... As of 145 AM Friday... Sat will be seasonably cool and dry for most of the area, as the surface front settles to our S. Models are in good agreement with the mid level pattern consisting of a deep closed low over New England moving NE to the Canadian Maritimes during Sat, while upstream energy diving through Quebec maintains broad troughing down through the Mid Atlantic region. This trough connects to a second, nearly stationary closed low that will hold over LA through Sat night. While this mid level shear axis appears likely to hold to our NW through Sat night, a weak but cool/dense surface high will build over NC during the day, then shift E off the coast while a portion of a stronger high builds from the NW into NC right behind it, resulting in dry low levels and limiting pops to nothing more than isolated patches of light rain over the extreme S, within a shallower and less dry subcloud layer. Otherwise, we will see considerable high cloudiness spreading out of the central and E Gulf coastal region to the NNE across NC, yielding a trend to mostly cloudy skies Sat that will hold through Sat night. Expect below normal highs of 70-75, followed by lows from around 50 to 55. -GIH && .LONG TERM /SUNDAY THROUGH THURSDAY/... As of 255 AM Friday... An overall wet period is ahead, with rain chances ramping up Sun/ Sun night, peaking Mon through Tue night, before finally decreasing gradually and shifting E Wed/Thu. Periods of heavy rain are possible, which may lead to flooding. Sun: The mid level low wobbles but holds over LA through Sun, but as it deepens a bit, the mid level S flow out of the N Gulf into SC will increase and deepen, suggesting a further-north drift of 1"+ PW into S NC. While northern sections of the CWA should still be dry Sun as the surface high drifts offshore, enough of the latest deterministic models and ensemble suites are indicating precip spreading N into W and far S NC during the day that warrant drawing chance pops further N into the CWA Sun. Any precip across our S Sun should be light, however, given the weak forcing for ascent including initially muted moist upglide. Below normal highs should persist with cloudy skies, again mainly 70-75, although the NE and far N CWA should be the warmest with lower readings in the S and SW. Sun night through Tue night: Confidence is increasing that much of the CWA, but particularly the S and W sections, could see at least a couple of rounds of heavy and potentially flooding rainfall during this time frame. By Sun evening/night, as the surface high pushes over and just off the New England coast with a tightening MSLP gradient between the high and deepening surface low pressure over the central Gulf Coast, the increasing low level E/SE flow into the Southeast will produce strengthening and deepening moist isentropic upglide, with a long fetch of Atlantic moisture driving high moisture transport into the Carolinas. Terrain upglide may enhance lift, and LREF probabilities of 1.5-2" of rain in 24 hours is over 30% across our SW half. The LA closed low will open a bit but drift only slowly NE into the Mid South through Tue night, while the MSLP gradient remains tight between the surface high over the NW Atlantic and developing low pressure over SC into GA, keeping us within a surge of 1.5-1.9" PW (150-170% of normal) over the entire CWA Sun night through Mon night, followed by a focus over our E half Tue into Tue night as the slow-moving H8-H5 trough axis shifts gradually ENE through the area, nudging the best moisture transport into E NC and E VA. Models agree on cycles of enhanced forcing for ascent, including strong and deep moist isentropic upglide Sun night through Mon night, with DPVA from energy lifting out of the NE Gulf, and a shot of upper divergence in the exit region of the S mid level jet late Mon night through the first half of Tue. With good agreement among deterministic models and ensemble means on this pattern, will carry high pops (likely to categorical) through much of Tue, with a NE shift in higher pops out of the CWA late Tue through Tue night as a dry punch arrives from the S. Still expect a smaller-than-usual diurnal temp range, with slightly below normal highs and above normal lows. Wed-Thu: An improving trend is expected mid week, although our eastern areas may stay unsettled longer. Cold/deep mid level troughing over the W CONUS and downstream ridging developing over the Miss Valley will nudge our Ohio Valley low/trough slowly E as it continues to slowly weaken. While confidence in the forecast details declines, we`re likely to see the trailing mid level trough extend from OH/PA/WV SSE through central NC Wed before easing ENE Wed night and Thu with the encroaching Miss Valley ridge. Will keep above- climo pops E through Wed with a surface frontal system or low expected to track slowly E through the state, with pops then trending to near climo by Thu. -GIH && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... As of 755 AM Friday... An area of IFR ceilings that developed in rain-cooled air and atop moist soil from Thursday`s storms, and amid subsequent deep layer clearing over the wrn Carolinas, will linger at INT/GSO through ~14Z. It may also advect enewd while lifting with the onset of daytime heating and briefly affect RDU with an associated MVFR ceiling between 14-16Z. Isolated showers/storms will probably redevelop along and ahead of a cold front over the nrn NC Piedmont by early this afternoon, then grow in coverage (to scattered) and intensity across the RWI vicinity through late afternoon-evening. However, coverage and intensity of today`s convection should be lower than what it appeared in previous forecast issuances, owing to both more-limited instability in the wake of Thursday`s widespread storms and also weak and exiting large-scale lift by this afternoon. Outlook: Flight restrictions and rain, some moderate to heavy, will become widespread next Mon-Tue. && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...CA NEAR TERM...CA SHORT TERM...Hartfield LONG TERM...Hartfield AVIATION...MWS