Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC
Issued by NWS Raleigh/Durham, NC
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206 FXUS62 KRAH 032028 AFDRAH Area Forecast Discussion National Weather Service Raleigh NC 328 PM EST Wed Dec 3 2025 .SYNOPSIS... Continental Polar high pressure will migrate across the Southeast through early Thursday. A dry cold front will lead Arctic high pressure across and offshore the Middle Atlantic later Thursday through Friday, while weak waves of low pressure will track along a wavy frontal zone from the northern Gulf to offshore the Southeast coast. && .NEAR TERM /THROUGH TONIGHT/... As of 1240 PM Wednesday... * Unseasonably cold with variable cloudiness through the overnight period. A broad area of 1022mb high pressure leaking across the southern Appalachians will continue to drift eastward throughout the day before becoming increasingly diffuse by Thurs morning. Patches of flat strato-cumulus clouds, visible on satellite imagery over the western Piedmont into the Sandhills and Coastal Plain, will provide locally greater coverage of partly to mostly cloudy skies through the afternoon before gradually thinning late this evening into tonight. Light surface winds will become more south to southwesterly through the afternoon and keep surface dew points fairly steady as moisture north of the stalled occluded front to our south counteracts the very dry air just above the PBL. Limited horizontal moisture advection is expected overnight within the weak pressure gradient, but relatively moist afternoon crossover temperatures and pockets of heavily saturated soils from Tues rainfall, may result in patchy fog. Widespread fog is not anticipated as waves of cirrus with varying thickness shift over the region overnight and should provide an unfavorable factor to an otherwise excellent radiational cooling night for radiation fog. Lows tonight will settle in the mid 20s to low 30s. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... As of 326 PM Wednesday... * Increasing clouds and milder/more-seasonable Thu * Precipitation developing, including a rain/snow mix that will probably transition to all snow for several hours across the nrn Piedmont, late Thu night-Fri morning Aloft, a southern-stream long wave trough will extend from western Mexico east through the Deep South and just offshore the Mid- Atlantic on Thursday. An associated anomalous upper jet (peaking into the 99th percentile) will strengthen across the Mid-Altantic Thursday evening resulting in increasing divergence over the southeast US. At the sfc, a strong Arctic high will move across the Ohio Valley and into the Mid-Atlantic Thursday, extending cold and direr air into central NC. The high will initially be favorably placed for light some wintry precipitation (mostly in the climatologically favored north of I-85 area) before weakening and progressing offshore Friday. Thursday should start off mostly sunny, but considerable cloudiness and moisture will spread south to north over central NC through Thursday evening. Temperatures will peak in the lower to mid 50s Thursday afternoon. Lift associated with increasing WAA in the mid-levels will generate a precipitation shield across the TN Valley that will quickly expand northeast along the southern Appalachians/Foothills/Piedmont through early Friday morning. Partial thickness and forecast soundings continue to suggest that an initial rain/snow mix on the northern periphery of the shield will likely transition to a period of all snow for a few hours (primarily along and north of I-85) Friday morning. Some light accumulations will be possible in this vicinity before thermal profiles trend above freezing via continued WAA and amid weakening cold/dry advection from the weakening/transitory sfc high. During this transition period, some sleet and/or freezing rain may develop again mostly along and north of I-85. However, without a persistent feed of cold/dry air, any ice accumulations should be fairly manageable/negligible. As we progress through Friday afternoon and evening, a sfc low will develop along the coastal Carolinas and drive offshore through Saturday morning. Lift associated with this feature (along with continued divergence aloft within the exiting jetstreak) will promote continued light rain primarily along and east of US-1 Friday night. A few models have hinted at some light freezing rain re- developing across the NC/VA border Friday night, but think this will trend drier with time. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... As of 140 PM Wednesday... * Mixed precipitation event possible Sun night into Mon, but synoptic pattern is typically unfavorable for impactful snowfall. * Bitterly cold temperatures possible Tues morning. A strong and elongated jet will be in place Sat morning from the southern Plains through the Mid-Atlantic and into the Atlantic with 150-175kts at 250mb (1-2 SD above normal). On the equatorward side of the jet, anomalous deep-layer moisture will remain in place with perturbed H5 flow directed across the Southeast and Mid-Atlantic. This should favor a continued chance for light rain possible through Sun. Although the mid-levels should still be cold enough for ice-crystal formation, lack of saturation above -8C and warming low- levels will keep all precipitation liquid through Sun. Forecast uncertainty increases with an added wrinkle of potential p- type concerns Sun night into Mon. The primary driver in uncertainty with this next system is the amplitude and propagation speed of the northern stream wave as it shifts across eastern Canada and the Northeast. Cluster analysis from the old 00z grand-ensemble suggest a quicker northern stream wave and shortwave ridging moving across the Northeast, resulting in a more favorable surface high placement ahead of the next wave, would provide a greater concern for snowfall in the Piedmont and northern Coastal Plain. Climatology suggest cold air arriving `just in time` for the onset of precipitation is typically not favorable for measurable snow in the Carolinas. This methodology and leaning on climatology keeps the forecast all rain for now. Forecast turns quieter and colder early next week as cold high pressure on the backside of the Sun night/Mon system filters into the area and PWAT values drop to well below normal. Tues morning could be bitterly cold with the surface high centered directly over the area. Lows in the low/mid 20s to upper teens Tues morning certainly appear possible. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... As of 1240 PM Wednesday... Scattered to broken MVFR stratocumulus has indeed blossomed over the Coastal Plain and eastern Sandhills (nearest FAY) this afternoon. A separate area around 3,500 to 5,000 ft stratocumulus from SC has spread north into the southern Piedmont with fleeting low-VFR cigs as far north as the Triad terminals. The MVFR stratocu may affect FAY vicinity for the next several hours before lifting to around 3,000-4,000 ft this evening. There is a potential for FAY to remain around high-MVFR cigs into late this evening, but opted for a more optimistic forecast for now. Cooling temperatures tonight, atop saturated soil from yesterday`s rain, will probably promote the development of at least patchy fog Thu morning, with highest probability of occurrence and lowest visibility restrictions from near CLT to FAY to OCW to as far north as RWI. Outlook: Another storm system is expected Fri into Sat and will likely bring flight restrictions to all central NC terminals. A period of snow/sleet remains possible for the northern terminals (GSO/INT/RDU) Fri morning before transitioning to all rain by the afternoon. && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...MWS NEAR TERM...AS SHORT TERM...Luchetti LONG TERM...AS AVIATION...AS/MWS