Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC
Issued by NWS Raleigh/Durham, NC
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695 FXUS62 KRAH 040550 AFDRAH Area Forecast Discussion National Weather Service Raleigh NC 1250 AM EST Thu Dec 4 2025 .SYNOPSIS... Weak high pressure will hold over the Southeast coast and eastern Carolinas this morning. A dry cold front will push southward through the region later today, settling just to our south as Arctic high pressure noses in from the north. Low pressure developing over the northern Gulf will track northeastward across the Southeast states and Carolinas late tonight through Friday. && .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 jet streak) 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 /06Z THURSDAY THROUGH MONDAY/... As of 1250 AM Thursday... With the exception of patchy MVFR fog over S and E areas until around 12z this morning, affecting RWI and perhaps FAY, VFR conditions are likely to hold across central NC today through at least mid evening (~03z Fri), but with increasing clouds. Weak high pressure over the eastern Carolinas will push SE and yield to a dry backdoor cold front that will drop S through the area later today, resulting in a shift of surface winds from light/variable this morning to light from the W or NW through mid afternoon, then shifting to be from the NE under 8 kts behind the backdoor front starting late today. Low pressure tracking NE from the N Gulf later today will bring increasing and thickening mid clouds from the WSW by afternoon, with slowly lowering bases. Clouds will become overcast after 22z, lowering further but still VFR through 03z, then there is a good chance for cigs to lower to MVFR at INT/GSO after 03z. Looking beyond 06z Fri, precipitation will spread into W sections including INT/GSO between 06z and 09z, before advancing over the rest of central NC after 09z, lasting through much of Fri, with a high chance of sustained sub-VFR conditions. This precipitation is likely to be mostly light snow at INT/GSO and a rain/snow mix at RDU at onset, with rain elsewhere. Precipitation will end W to E late afternoon through the evening, perhaps as a little drizzle or freezing drizzle, but sub-VFR conditions are likely to hold through Sat morning. Rain chances producing a period of sub-VFR conditions will continue at FAY Sat through Mon, with the highest chance late Sun into early Mon. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Hartfield NEAR TERM...AS SHORT TERM...Luchetti LONG TERM...AS AVIATION...Hartfield