Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC

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000 FXUS62 KRAH 020742 AFDRAH Area Forecast Discussion National Weather Service Raleigh NC 240 AM EST Fri Dec 2 2016 .SYNOPSIS... High pressure will build over the Eastern U.S. from the west through the upcoming weekend. An approaching upper level disturbance and moist flow from the Atlantic and Gulf will bring increasing rain chances beginning Sunday night. && .NEAR TERM /today through tonight/...
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As of 205 AM Friday... Another quiet day with high pressure building in at the surface from the NW, and rising heights aloft as the axis of the broad mid level ridge shifts eastward over the Southeast states. Forecast soundings unanimously show a dry and stable column, with the only clouds likely to be a few high thin clouds resulting from minor high level moisture within a fast mid-upper flow across the region. Slightly below normal thicknesses projected today balanced by abundant sunshine should yield highs close to normal, from the mid 50s to around 60. High thin clouds will continue to stream into the area tonight as blowoff from TX convection tops the broad ridge and srreams into the region. Lows 30-36 under fair skies with light winds. -GIH
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&& .SHORT TERM /Saturday through Saturday night/...
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As of 240 PM Thursday... The surface ridge, centered over the central Miss Valley early Sat, shifts NE through the Great Lakes region through Sat night while continuing to extend SE through NC. Pieces of energy emanating from the deep low over NW Mexico will slowly break down the ridge as they ride along its top into NC, resulting in slowly thickening and lowering clouds, particularly Sat night. Expect mostly sunny skies early Sat to trend to partly sunny in the afternoon, then to cloudy Sat night from SW to NE as moist upglide strengthens and deepens in the mid levels. Expect no pops, however, as the column remains quite dry below 700 mb. Thicknesses should be slightly lower Sat than on Fri, suggesting cooler highs in the lower to mid 50s. Increasing clouds should limit radiational cooling in the SW CWA Sat night, lesser so in the NE, so expect lows to range from the mid 30s NE to around 40 SW. -GIH
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&& .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... As of 335 PM Thursday... The extended forecast will be characterized by a series of shortwaves progressing through the central U.S. Though the model solutions are in much better agreement for Sunday through Tuesday, significant model differences arise thereafter. As a result, forecast confidence beyond Tuesday is quite low. Sunday through Tuesday: An upper level cut-off low over NW Mexico will usher a good amount of moisture into the Gulf Coast states and southeast U.S. Sunday while a weak ridge lingers over the east coast. Meanwhile, a northern stream shortwave over the Midwest will progress eastward, though the impact it will have on the ridge is a bit uncertain and will have an impact on the northeastward extent of the Pacific moisture. The better chance for rain to move into the region will come Monday and Tuesday as the aforementioned low starts to move northeast through the Midwest and interacts with another shortwave traversing a strengthening trough over the Rockies. The advection of additional moist air being picked up off the Gulf in the southwesterly flow will result in increasing chances for rain over the Carolinas. Highs Sunday will still be somewhat cool, upper 40s to low 50s before warming up into the mid to upper 50s Monday and Tuesday. Lows will generally be in the upper 30s to low 40s. Wednesday and Thursday: The low should be absorbed into the northern stream flow by late Tuesday/Tuesday night and the rain should exit to the east Tuesday night. Though the upper level patterns appear similar on Wednesday and Thursday, the difference in the strength and location of the next low/trough is significant. As a result, forecast uncertainty is high with respect to both weather and temperatures. Per the GFS...Central NC could get a quick shot of rain followed by strong cold advection and the chance to see lows in the low to mid 20s Thursday night. Conversely...the ECMWF is stronger and slower with the system and given the latest solution, the rain would be delayed until late Thursday/Thursday night. For now, will keep this period dry with highs in the mid 50s to low 60s and lows decreasing from 40s Wednesday night to 20s and 30s Thursday Night. && .AVIATION /06Z Friday through Tuesday/... As of 1235 AM Friday... High confidence in VFR conditions for the next 24 hours. High pressure will continue to build into the region, with deep dry air as mid level ridging shifts over the Southeast states. Only a few thin high clouds are expected across the area today through tonight, and low humidities will result in VFR vsbys. Surface winds will be light from the NW through daybreak, then from the W or WNW at 8-12 kts through sundown, and light from the NW again tonight. Looking beyond 06z Sat: High clouds will steadily increase and thicken with lowering bases to around 10 000 ft AGL through Sat night, and to around 5 000 ft AGL Sunday with light rain spreading in late from the SW as an upper level disturbance approaches from the SW and a surface frontal zone moves in from the south. Confidence is high that conditions will deteriorate further to IFR Sunday night and remain poor at IFR or LIFR Monday into Tuesday with periods of rain and potential low level wind shear. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Hartfield NEAR TERM...Hartfield SHORT TERM...Hartfield LONG TERM...KCP AVIATION...Hartfield

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