Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC

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000 FXUS62 KRAH 220116 AFDRAH Area Forecast Discussion National Weather Service Raleigh NC 908 PM EDT WED SEP 21 2016 .SYNOPSIS... An upper-level low across the eastern Carolinas will drift slowly south and weaken tonight and Thursday. Otherwise a moist, northeasterly low level flow will persist for much of the work week. && .NEAR TERM /OVERNIGHT/...
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As of 908 PM Wednesday... The main weather concerns tonight are around the heavy rain threat over NE Carolina associated with the deep easterly flow to the north of the main mid/upper level low pressure. The mid/upper level low pressure was still lingering over eastern NC this evening. The main problem area is to the north of the low over northeastern NC and southeastern VA, where the deep and moist onshore flow continued to promote areas of heavy rain. Rainfall rates over the NE part of our region under some of the heavier showers have been less than 0.50 inch per hour in the past 5-6 hours, producing 6 hourly totals of 2.5 inches around Roanoke Rapids. These heavy rains falling on the already saturated soils did lead to some reports of high water, but no road closures in that region. Rainfall rates in the past few hours have backed off as have the reports of high water around Halifax. Satellite and radar data suggest that some of the Hi-Res models were overdone on the coverage and rainfall rates now, and in the previous 6 hours. In addition, the models were too quick to move the heavy showers southward. Although a flash flood watch was considered for the Roanoke Rapids to Tarboro areas, we decided to hold off due to the expectation that flooding (if it does develop) would most likely be localized to one or two counties, and the uncertainty of whether or not additional training would occur over the same regions that had the heaviest rain in the past 12-24 hours or spread out into lighter totals to the south and west. Elsewhere, spotty light rain showers were observed over the eastern Piedmont through the Sandhills and southern Coastal Plain region. No showers were noted over the western Piedmont. For the overnight, we will maintain the categorical POP in the Coastal Plain with likely POP into the eastern Piedmont,dropping off rapidly to less than 20 POP in the west. Low overcast in the east ranging to partly cloudy skies in the Yadkin Valley. Lows in the 60s expected.
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&& .SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/... As of 400 PM Wednesday... Not a lot of change in the weather pattern for Thursday and Thursday night but a gradual shearing and weakening of the upper low and filling of the surface low will decrease the moisture transport and limit precipitation coverage. While scattered showers and even a thunderstorm are possible again on Thursday, the coverage will be notably less than previous days with a focus across the Coastal Plain and eastern Piedmont. Rainfall rates and intensity will be less than previous days as well. A widespread overcast is expected to start the day with some thinning and breaks in the overcast expected during the afternoon. Highs will range in the upper 70s to lower 80s. Scattered showers and isolated thunderstorms on Thursday afternoon will gradually diminish on Thursday evening with the loss of heating. Skies will become mostly cloudy again overnight with lows in the mid 60s to near 70. -Blaes && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... As of 225 PM Wednesday... The upper cutoff low fills and is gradually absorbed into the long wave trof over the eastern CONUS...allowing the airmass over the area to finally dry out Friday into Saturday as deeper moisture is nudged offshore. Increasing sun will allow temps to recover backtoward normal...mostly mid 80s Friday...with mid and upper 80s onSaturday. The east coast trof deepens and a backdoor cold front surges south down the coast by mid day Sunday. Condensation in the cool air advective regime behind the front will lead to mostly cloudy skies with perhaps some patchy light rain through Sunday night. Highs will be mostly in the upper 70s across north to lower 80s south. The cool ridging behind the front will be locked on Monday...with mostly mid 70s highs...warming to the upper 70s for Tuesday with some lower 80s on tap for Wednesday ahead of our next front approaching in the late week. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... As of 840 PM Wednesday... 24 Hour TAF Period: An upper level low pressure system will bring a period of adverse aviation conditions with sub-VFR conditions across central NC into Thursday. Periods of rain will continue to rotate through the area through Thursday, with the bulk of the rain tonight affecting KRWI/KRDU and possibly KGSO and KINT while the main axis of precip on Thursday should be further east and closer to KRWI and KFAY. Cigs are expected to fall into the IFR category overnight, before slowly improving to MVFR by late morning/early afternoon Thursday, possibly reaching VFR at a few sites during Thursday afternoon. However, the latest hi-res guidance continues to hint at the potential for some LIFR cigs and/or visbys at KRWI and KFAY within +/- a couple of hours of daybreak. North-northeasterly winds are expected to continue through the period in the 8 to 13 kt range, with possibly some gusts to as high as 20 kts this evening and again on Thursday. Outlook: An upper-level low across the coastal Carolinas will slowly weaken on Thursday night and Friday. A moist, northeasterly low level flow will persist into the first part of the weekend resulting in periods of adverse aviation conditions with sub-VFR ceilings, especially during the overnight and reduced visibilities in scattered showers. A cold front will push through the region late Saturday resulting in improving conditions for Sunday and Monday. && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Badgett NEAR TERM...Badgett SHORT TERM...BLAES LONG TERM...mlm AVIATION...BLAES is the U.S. government's official web portal to all federal, state and local government web resources and services.