Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC

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000 FXUS62 KRAH 120610 AFDRAH Area Forecast Discussion National Weather Service Raleigh NC 110 AM EST Tue Dec 12 2017 .SYNOPSIS... A pair of dry cold fronts will cross central North Carolina today. Cold high pressure will build in tonight through Wednesday. A fast moving upper level disturbance will move through the region Wednesday night. && .NEAR TERM /TONIGHT/... As of 925 PM Monday... Clear skies this evening will give way to increasing cloud cover overnight as a potent s/w disturbance and associated cold front approach from the west. In addition to the increasing cloud cover, expect we`ll see winds stay up overnight (generally light out of the south to southwest). This will lead to warmer overnight low tonight, with temps possibly even rising a few degrees after midnight across the western portion of the area as cloud cover increases. Thus, expect low temps will generally range from around 30 in the usual rural cold spots to the mid 30s in the urban areas. && .SHORT TERM / TUESDAY AND TUESDAY NIGHT/... As of 300 PM Monday... ...Gusty NW winds to 25-30 mph with wind chills in the 10-15 degree range Tuesday evening... The main cold front and upper level feature will move across central NC between 12z and 18z. This is when the mid and high level moisture will increase enough for variably cloudy skies. Once the cold front passes, winds will shift to the WSW and increase to 15-20 mph with gusts to 30 mph. CAA will be delayed a few hours behind the front due to the strong westerly downslope component. Guidance is robust in warming temperatures well into the mid 50s to lower 60s in the east, with highs 50-55 NW. Expect a very sharp drop in the temperatures late Tuesday and Tuesday evening with strong cold dry air advection. Readings will slip below freezing within a few hours of sunset in the Triad, and by late evening in the Triangle. Mainly clear skies and diminishing winds are expected late Tuesday night. Lows will be in the lower to mid 20s. Wind chill readings of 10-15 are likely from mid evening through the early morning hours. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... As of 230 PM Monday... Cold air will be advecting into Central NC in northwest flow on Wednesday in the wake of the dry cold frontal passage. Despite full sun, highs will be capped in the mid 30s north to low 40s south. Overnight lows in the mid to upper 20s. Meanwhile, a shortwave will begin diving south-southeastward from central Canada, through the High Plains and toward the Mid-Atlantic. The resultant upper level winds will become briefly more westerly then southwesterly on Wednesday night. A reflection of this wave will be seen at the surface as a low moving through the OH Valley region, eastward to the Atlantic. The winds will become more southwesterly at the surface late Wednesday/Wednesday night ahead of the aforementioned low and its attendant cold front. This cold front, which won`t be as potent as the previous one, will stall over Central NC Thursday into Friday. A low strengthening along the stalled front over the area will result in an increase in temperature gradient from WV to SC on Friday. Persistent west-southwesterly flow into the region will result in increased warm, moist air advecting into the Carolinas and thus an increase in precipitation potential, mainly along and ahead of the front. The front should finally move eastward over the Atlantic late Friday into Saturday, allowing cold air to advect into the area from the northwest as high pressure migrates eastward along the Gulf coast, ridging into the Carolinas. Another frontal system develops in the Midwest Saturday/Sunday, approaching the Mid- Atlantic Sunday/Monday. Medium range models are in fairly good agreement for being so far out in time, so this may be a system of focus for the next week or so. Highs through Saturday will generally range from mid 40s to mid 50s, while lows will fluctuate between low to mid 30s and mid to upper 20s. Ahead of the next frontal system, temperatures will likely moderate, highs the mid 50s and lows into the mid && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... As of 110 AM Tuesday... High confidence in VFR conditions for the next 24 hours across all of central NC. But a surge of strong and gusty winds today may lead to handling difficulties with aircraft this afternoon through tonight. A dry cold front and potent upper level trough will cross the area today, bringing a period of VFR cigs with cloud bases over 5,000 ft AGL and unrestricted vsbys. Surface winds will veer from SW to WNW and NW with frontal passage, occurring around 14-15z at INT/GSO and 15z-18z at RDU/RWI/FAY. Sustained speeds post-front of 12-17 kts, with gusts to 22-28 kts, are likely, continuing through much of tonight as colder air pours into the area. Looking beyond 06z Wed, surface winds will decrease overnight and back to WSW by daybreak Wed. VFR conditions will hold through Wed, then the approach and passage of an upper level disturbance across VA and northern NC may bring a period of cigs (likely VFR but may be briefly high-end MVFR) Wed night with a possible flurry. VFR conditions should then dominate Thu through Sat, although yet another disturbance may bring a period of MVFR cigs Fri. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Hartfield NEAR TERM...BSD SHORT TERM...Badgett LONG TERM...KC AVIATION...Hartfield is the U.S. government's official web portal to all federal, state and local government web resources and services.