Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC

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898 FXUS62 KRAH 271733 AFDRAH Area Forecast Discussion National Weather Service Raleigh NC 132 PM EDT Mon May 27 2024 .SYNOPSIS... Unseasonably warm and humid airmass will continue unsettled conditions through tonight. A series of cold fronts will move through central NC through mid week with high pressure building overhead for the weekend. && .NEAR TERM /THROUGH TONIGHT/...
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As of 855 AM Monday... ...There is a level 2 risk for severe storms today with another unseasonably warm and humid airmass in place... Continued uncertainty today wrt to thunderstorm coverage. The well forecasted upstream MCS has largely decayed east of the mountains. Convective cloud debris has overspread much of the western to central Piedmont, with some clearing out ahead across the southern Piedmont/Sandhills/southern Coastal Plain. Given the extensive cloud cover this morning, it`s still not entirely clear how much recovery we`ll see later today. Nonetheless, there is clearly a few MCV features embedded within the decaying MCS evident on regional radar that may generate convection along either a developing lee-trough or along the cold pool. It appears that the best coverage (after this morning`s convection moves northeast of our area) potential may be across the southern Piedmont/Sandhills/Coastal Plain through early this afternoon. Guidance suggests an MCV embedded within the deeper convection currently over Georgia may drive through these areas later today (also where residual CIN will likely erode the quickest). However, can`t rule out storms blossoming further north, as a few weaker MCVs currently moving across southwestern VA and the NC high terrain move east across the NC/VA border. Overall, the parameter space still suggests any storm that fires could become severe today with strong mid-level lapse rates and plenty of effective shear to play with. Morning RAP-derived hodographs, as well as VWP profiles depict some curvature in the wind field across much of central NC thus far. Despite this, we have some residual stable conditions near the sfc early this morning. Thus, convection thus far has been largely elevated in nature. It would appear that as we progress this morning, hail may be the better threat at first, before transitioning to a more-so damaging wind threat as that sfc stability erodes quite quickly this morning (already see 70 temps over upper 60s dew points). The low-level flow will also continue to strengthen as we progress into the afternoon hours, and as such, better kinematics will support a non-zero chance for a few tornadoes today. The better tornado probabilities still appear to be east of US-1 (and moreso into MHX/AKQ`s CWAs), but rotating storms will be possible across all of central NC through early this evening. Overall storm motion should be quick enough to preclude widespread flooding concerns. However, given how juicy the atmosphere is, can`t rule out isolated urban and low-drainage flooding from any heavier downpour today. Rain chances should diminish later this evening as drier air punches in from the west. Persistent swly flow will promote highs in the mid to upper 80s/lower 90s.
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&& .SHORT TERM /TUESDAY AND TUESDAY NIGHT/... As of 305 AM Monday... Aloft, a s/w should track through SC Tue then out over the Atlantic Tue night as the base of the trough moves over central NC. Meanwhile at the surface, the cold front should be over the NC Piedmont by daybreak Tue, then continue eastward through the area through the day and offshore Tue night. Expect NW flow in the wake of the front Tue, however the arrival of cooler air may be delayed until Tue night. Cannot rule out a shower/storm over the southern/central Coastal Plain on Tue ahead of the cold front, but that activity will move out with the passage of the front and dry weather is expected area-wide Tue night. Highs Tue should generally range from low/mid 80s north and northwest to upper 80s south and southeast. Lows Tue night will depend on the arrival of cooler air, but for now expect upper 50s north to low/mid 60s south. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... As of 230 AM Monday... An upper level trough will amplify as it progresses eastward over and through the mid-Atlantic and Carolinas. Several s/w disturbances will pass over the area as they swing through the trough, however for now they still appear relatively moisture-starved. The trough should shift offshore over the weekend, with the sub-tropical ridge slowly progressing eastward through the area behind it. At the surface, with the cold front offshore by early Wed, a trough may linger over central NC Wed before cool high pressure builds in from the west Wed night through Fri. The high should be over central NC Fri night/Sat. Forecast confidence decreases beyond Sat as model solutions diverge. For now, expect largely dry weather through Sat night, although will have to keep an eye on the passing s/w disturbances for potential precipitation development. Temperatures should be near normal for Wed, then near to below normal through the remainder of the forecast period. && .AVIATION /18Z MONDAY THROUGH FRIDAY/...
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As of 132 PM Monday... Outside of temporary restrictions from scattered afternoon convection, VFR conditions should largely prevail through the 24 hr TAF period. There is considerable uncertainty wrt to convection the rest of today. Observational and model trends suggest the best chance for storms would be at the eastern TAF sites the next several hours. However, confidence in any storms impacting even these airports is quite low. Otherwise, expect layered VFR clouds to persist through much of the rest of the period, with perhaps some scattered stratus across the east early Tuesday morning. Gusty sswly sfc flow will subside around sunset tonight, with light winds expected overnight. Outlook: VFR conditions should persists through the extended as dry high pressure wedges in.
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&& .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Swiggett NEAR TERM...Luchetti SHORT TERM...KC LONG TERM...KC AVIATION...Luchetti