Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC

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000 FXUS62 KRAH 281642 AFDRAH Area Forecast Discussion National Weather Service Raleigh NC 1245 PM EDT SUN AUG 28 2016 .SYNOPSIS...
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High pressure will persist over the region through today. An upper level disturbance over the Atlantic will drift west toward the Carolina coast through Tuesday.
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&& .NEAR TERM /THROUGH TONIGHT/... As of 1025 AM Sunday... Little change required to the near term forecast. Patches of low clouds/stratus have begun to erode. This should lead to mostly sunny or partly cloudy skies at most locations by mid day. 12Z upper air analysis depicts an area of high pressure at the surface and aloft extending sw-ne across most of the western Piedmont. Subsidence associated with this feature should inhibit convective development later this afternoon. In the east, low level analysis depicts a weak trough and attendant weak moisture convergence along the eastern periphery of our forecast area. This should aid in the development/maintaining isolated to scattered convection later this afternoon. Best threat for a shower or storm should be confined to locations east of I-95, and more so in vicinity of Goldsboro and Clinton. 850MB temps are about 3 deg C cooler compared to same time Saturday. This supports afternoon temps a solid 5-7 degrees cooler than Saturday. This yields max temps this afternoon near 90 to the lower 90s. A steady east-ne confluent onshore flow aided by the approach of a developing tropical depression off the NC coast will result in variably cloudy skies and a threat for showers along the east-se fringe of our forecast area. Otherwise expect mostly clear-partly cloudy skies elsewhere. Overnight temps near 70-lower 70s. && .SHORT TERM /MONDAY THROUGH MONDAY NIGHT/... As of 400 AM Sunday... Monday looks fairly similar to today, with the upper low drifting inland over SC and briefly stalling. A strong moisture gradient will set up again with the surface ridge and deeper mixing in the west, and better moisture/instability over the coastal plain. A weak offshore surface low drifting toward the NC coast will have little impact here, and scattered showers and a few storms will again be confined to the southern coastal plain. Highs in the upper 80s and lower 90s. Lows monday night in the upper 60s and lower 70s. .LONG TERM /TUESDAY THROUGH SATURDAY/... As of 226 PM SATURDAY... WV imagery this morning depicts an increasingly well-defined mid to upper level low off the SERN U.S coast. The forecast models continue to indicate this feature will drift W --around the SRN periphery of the initially strong sub-tropical ridge centered over the Middle Atlantic states-- and stall along the SERN U.S. coast early this week, before shearing out and lifting away from the region through the middle of the week. The presence of this mid-upper low, and a NRN stream trough forecast to migrate across the NERN U.S through early week, will cause the preceding sub-tropical ridge to succumb over the Middle Atlantic states and ultimately split, with one center expected to retrogress into the central U.S. and the other retreat into the central N. Atlantic Ocean. A broad trough will develop between the two /over ERN U.S./ through the end of the week. This pattern aloft will play an important role in what becomes of the now well-advertised tropical wave along the NRN coast of Cuba this morning, which the models now generally agree will enter the ERN Gulf of Mexico early to mid-week. Significant model spread regarding the track and timing of the associated low develops thereafter, though it seems reasonable that low will eventually be influenced by the aforementioned ERN CONUS trough aloft and be drawn NEWD through or along the SERN U.S coast, with an associated increased probability of rain, through the end of the forecast period. Of greater predictability will likely be a NRN stream cold front forecast to settle through the SRN Middle Atlantic states and Carolinas Thu-Fri, with an accompanying chance of convection maximized in central NC Thu-Thu night. Cooler and drier conditions in post-frontal high pressure ridging across the Middle Atlantic region would follow, though the duration of this post-frontal regime will hinge upon what happens with the tropical low and associated moisture potentially approaching from the south later Fri and Sat. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/...
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As of 1245 PM Sunday... There is high confidence that VFR conditions will prevail across the western Piedmont of central NC through Monday night as an area of high pressure at the surface and aloft extends overhead. Surface winds out of the northeast may be breezy at times Monday, gusting between 14-18kts. Along and east of the highway 1 corridor, periods of cloudiness will occur, resulting in MVFR/IFR ceilings, with the lowest ceilings expected between 09Z-15Z Monday. A few showers may skirt in vicinity of KFAY and KGSB , and south of KRWI this afternoon through early evening, and again Monday afternoon. The difference in pressure between the high to the west and the approach of tropical depression to our east will yield breezy northeast winds Monday of 10-14kts with occasional gusts near 20kts. The above conditions expected to occur again Tuesday. Forecast confidence lowers for the remainder of the work week as model guidance offering varied solutions concerning the approach of a low pressure system from the south-southwest, and a cold front from the nw. At this time, the risk of adverse aviation conditions appear greater at KFAY and KRWI, and less so at KRDU, KGSO, and KINT.
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&& .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...BS NEAR TERM...WSS SHORT TERM...BS LONG TERM...MWS AVIATION...WSS is the U.S. government's official web portal to all federal, state and local government web resources and services.