Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC
Issued by NWS Raleigh/Durham, NC
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352 FXUS62 KRAH 082101 AFDRAH Area Forecast Discussion National Weather Service Raleigh NC 400 PM EST Sat Nov 8 2025 .SYNOPSIS... A front will become quasi-stationary over NC through tonight, then retreat north into VA as a warm front on Sunday. A stronger, polar front will sweep across the region early Sunday night. A vigorous mid and upper-level trough and Arctic cold front will then move across the region late Monday into Monday night. && .NEAR TERM /THROUGH TONIGHT/... As of 149 PM Saturday... * Elevated convection tonight with a marginal risk for hail and damaging winds across the southern Piedmont/Sandhills/Coastal Plain. * Dense fog possible across the northern Piedmont/Coastal Plain later tonight. Satellite imagery this afternoon shows upstream cu development over north-central GA and parts of south-southeastern SC. Lingering fog/stratus over the north central SC Piedmont has finally dispersed this afternoon, with cu likely to develop in this vicinity shortly as low-level CIN continues to erode. At the sfc, the quasi- stationary front remains draped westward from our northern/central Coastal Plain through the western Piedmont. Embedded within an increasing WAA regime, largely elevated showers and storms will blossom across northeastern GA/western SC this afternoon and spread north into central NC this evening through the overnight period. Forecasted hodographs continue to highlight elongated profiles, with plenty of shear for storm organization especially across southern Piedmont/Sandhills/Coastal Plain locations where elevated instability should be highest. While mid-level lapse rates aren`t overly impressive (6.5 C/km), the 12Z HREF continues to double down on a decent clustering of mid- level helicity swaths over southern areas into the overnight hours. The previous 00Z run was more bullish on potentially anti-cyclonic rotation, but given the potential for supercells in this vicinity within a mostly elevated unstable regime, the main potential hazard continues to be large hail tonight (isolated damaging wind gusts possible too). SPC decided to introduce a 2% tornado contour across our southern Piedmont/Sandhills/southern Coastal Plain with this morning`s Day 1 update. Forecast soundings along the NC/SC border do show perhaps a very brief window where enough sfc instability may coincide with developing supercells to perhaps provide the potential for an isolated tornado. However, the WAA really doesn`t amplify until closer to sundown when sfc stability quickly takes over. As such, think that the threat for an isolated tornado may be a bit further southwest into SC. However, can`t fully rule out an isolated tornado in the NC/SC border vicinity (southern Anson, Richmond, Scotland, Hoke). Beyond 23/00Z, the nocturnal low-level inversion should quickly develop and transition the storm mode to elevated rotation and the aforementioned hail/wind threat. Beyond severe weather, the 12Z HREF LPMM field continues to highlight the potential for some potential higher totals (2 to 4 inches) across the southern Piedmont/Sandhills where cells may train along the boundary. Showers and storms should exit to our northeast through sunrise Sunday morning. However, similar to last night, there is a signal for possible dense fog again tonight, primarily north of the boundary across the northern Piedmont/Coastal Plain. Overnight lows in the mid to upper 50s are expected. && .SHORT TERM /SUNDAY AND SUNDAY NIGHT/... As of 100 PM Saturday... * Conditional severe threat remains ahead of the front, mainly along/east of US-1/I-95 * Strong cold front passage Sunday evening/night, with a drastic change in temperatures Overview: Aloft, a series of shortwaves swinging around a parent low near Hudson Bay will quickly act to amplify the longwave trough. The leading s/w will lift newd from the OH Valley across the Northeast, quickly followed by the next s/w, tracking slightly farther south and east. The third, strongest s/w will drop south across the wrn Great Lakes on Sun, then closing off as it continues ssewd across the OH/TN Valley Sun eve/night. At the surface, the low lifting nnewd out of the area Sun morning will merge with the low tracking ewd across the mid-Atlantic on Sun. As this low then continues generally ewd across the mid-Atlantic Sun aft/eve, the trailing cold front will move into the area from the west. The cold front should move quickly across the area Sun eve, and shift offshore Sun night. Cold, dry air will filter in behind the front Sun night, as the Arctic high settles swd over the Plains. Precipitation: There could be a few lingering showers along the VA border early Sun, but expect a lull in precipitation Sun morn and early aft. While most of the guidance shows convection developing Sun eve/early overnight across the ern Piedmont, Sandhills, and Coastal Plain, the later timing (after sunset) could reduce the available instability for showers to work with, with the best forcing chasing the best instability. While the HRRR and NAM both show MLCAPE maxing out around 800-1000 J/Kg during the aft, the available moisture remains limited (PWATS of 1.0-1.2 inches). However, given the strong wind fields, no surprise the bulk shear is high, 50-70 kts. There may be a brief window of opportunity for overlap with the forcing along the front tapping into some of the better instability and enough moisture to get a stronger storm to pop, but the threat remains conditional. The Marginal Risk from the SPC remains over the Coastal Plain. Expect an area of rain to develop behind the front as H85 trough moves into the area and the mid levels saturate, with warm moist air overrunning CAA at the surface. Rain should move out of the area by daybreak Mon. Temperatures: Highs Sun should be well above normal Sun, low 70s north to mid/upper 70s SE. Temperatures will quickly fall in the wake of the cold front Sun eve/night, with mid/upper 30s NW to mid 40s SE by daybreak Mon, near normal, but significantly lower than the previous couple nights. && .LONG TERM /MONDAY THROUGH SATURDAY/... As of 355 PM Saturday... Dry weather will prevail through the extended period under the influence of high pressure and NW flow aloft behind a vigorous mid/upper trough. An intense cold snap on Monday/Tuesday will be short-lived as temperatures turn seasonable by mid to late week. In the wake of Sunday night`s strong cold front, anomalously deep mid/upper troughing will extend across the Eastern US, and a Canadian surface high will move from the Southern Plains to the Gulf Coast. Strong CAA will bring in sharply colder and drier air to central NC on Monday with high temperatures ranging from mid-40s to mid-50s. This is 10-15 degrees below normal for this time of year. Dew points will also drop into the teens and 20s through the day. It will be blustery with BUFKIT soundings from the GFS and NAM depicting wind gusts of 20-30 mph will be possible at times. The big story of the period will be Monday night`s lows. Given 1000-850 mb thicknesses bottoming out in the 1270-1280 m range, a freeze is likely across much of not all of central NC. Temperatures are expected to drop into the mid-20s to around 30, coldest in the outlying areas of the Piedmont and warmest in urban parts of the Triangle, eastern Sandhills, and central/southern Coastal Plain. We should stay well mixed on Monday night as a vigorous shortwave tracks across the southern Mid-Atlantic and pushes a reinforcing Arctic front through the region. So NW winds will remain gusty, and wind chills are likely to drop into the teens and lower-20s in many areas. A minority of ensemble members particularly from the ECS depict potential for a very light rain/snow mix or some flurries across our NE counties with the shortwave on Monday night. However, it will be fighting dry air and strong downsloping westerly flow. So confidence is low at this time. Cold blustery conditions will continue on Tuesday with highs in the upper-40s, along with westerly winds that could again gust to 20-30 mph. The air mass will begin to modify on Tuesday night and will rapidly do so on Wednesday as the strong mid/upper trough pushes to our east and the low-level flow turns SW with the surface high extending farther east the western Atlantic. Forecast lows Tuesday night are in the lower-to-mid-30s, while forecast temperatures Wednesday are only slightly below normal with highs in the upper-50s to lower-60s. We will turn even milder from Thursday through Saturday with highs in the 60s and lows in the upper-30s to lower- 40s (except slightly cooler Thursday night as the next Canadian surface high moves overhead). Will have to watch fire weather concerns particularly Wednesday/Thursday as we warm back up, stay breezy, and RH values bottom out in the 25-35% range each day. But will have to see how much rain falls this weekend before having too much confidence. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... As of 1246 PM Saturday... VFR conditions will persist early this afternoon with some lingering mid to high level cloudiness across the Piedmont. Later today, showers and storms generated by increasing warm air advection will propagate from eastern GA/western SC northward into central NC this evening and overnight. Associated low-level moisture flux will sock ceilings back down to LIFR/IFR late this evening and persist through the overnight hours. Brief periods of reduced visibility, gusty winds, and perhaps isolated hail could accompany any stronger storm with best chances at KRDU/KFAY/KRWI between ~23 and 06Z tonight. Any lingering convection should exit to our northeast by sunrise Sunday morning. Additionally, dense fog may again be possible tonight with best chances over the Piedmont TAF sites. Any lingering fog/sub-VFR ceilings should lift by 15Z (perhaps a a bit later at KRDU/KRWI). Sly gusts of 15 to 25 kts will be possible Sunday afternoon and evening ahead of a strong polar front. Outlook: Similarly strong and gusty nwly sfc winds funnel in behind the polar front Sun night into early Mon. A vigorous trough aloft and accompanying Arctic, surface cold front will move across the region late Mon and Mon night, with a renewed surge of even stronger nwly gustiness and virga. && .RAH WATCHES/WARNINGS/ADVISORIES... && $$ SYNOPSIS...MWS NEAR TERM...Luchetti SHORT TERM...10 LONG TERM...Danco AVIATION...Luchetti/MWS