####018009709#### FXUS61 KLWX 111435 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 935 AM EST Thu Dec 11 2025 .SYNOPSIS... A cold front attached to a clipper system will exit into the Atlantic this morning. Another fast moving frontal system will cross south of the region by Friday. A strengthening wave of low pressure may impact the area Saturday night into Sunday before Arctic high pressure moves in by early next week. This ridge exits offshore by mid-week ahead of the next frontal system. && .NEAR TERM /THROUGH TONIGHT/... Mid-morning update: Earlier Blizzard Warnings and Winter Weather Advisories in the Alleghenies have been cancelled. A few lingering light snow showers and instances of blowing snow may remain possible there throughout the day. Further to the east, a wavy stratocumulus deck has developed at the top of the boundary layer, providing mostly cloudy skies and a few flurries. Model soundings show some weak dry advection at the top of the boundary layer over the next few hours, so current expectation is for the amount of cloud cover to trend downward as we head into the afternoon, and for any flurries to come to an end. Previous discussion follows... The current synoptic pattern features a deep closed low along the Ontario/Quebec border. This is part of a broader longwave trough which extends down into the Great Lakes and northeastern U.S. While the lead frontal system has exited into the western Atlantic, a secondary surge is underway in response to the next cold front. This is most evident in the uptick in west to northwesterly winds with gusts rising to 20 to 25 mph, with 30 to 40 mph in the mountains. Mountain snow showers are expected to taper off through the morning before the next round arrives by early Friday. Otherwise, outside of the Alleghenies, expect increasing sunshine heading toward the afternoon. However, this does come with another day of below average temperatures along with a blustery northwesterly wind. Forecast highs will range from near freezing to around 40 degrees, but with upper teens to 20s in the mountains. Afternoon wind gusts are likely to top out around 25 to 30 mph, locally up to 40 mph across the Allegheny ridgetops. Wind chills will fall into the single digits to mid teens over the higher elevations. The deep upper low initially over southwestern Quebec will slide across New England toward the Canadian Maritimes late tonight. However, in the wake, a broad west-northwesterly flow regime sets up which comes with a series of embedded progressive shortwaves. This steers additional mid/upper moisture toward the area overnight. Clouds will thicken through the night with low temperatures falling into the low/mid 20s, with teens across mountain locales. Any precipitation chances should hold off until daybreak Friday. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... As a series of waves dig across the Ohio Valley toward the southern Mid-Atlantic, the accompanying frontal system will track south of the region. Light snow spreads from the Alleghenies toward the central Shenandoah Valley and to the I-64 corridor. Moisture is rather scant in this clipper pattern which would overall limit the snow potential on Friday. Perhaps an inch of snow is possible, locally a bit higher where orographic lift augments totals. Heading toward the D.C. and Baltimore metro areas, will maintain a 20 to 30 percent chance for light snow. However, chances do appear better back toward the mountains and well south of the metros. With the frontal system tracking south of the local area, gradients remain on the weaker side which favors lighter winds than previous days. The forecast remains chilly with Friday's highs confined to the 30s (20s in the mountains). This is all underneath mostly cloudy skies and the mentioned light snow threat in spots. Heading into Friday night, the focus for any wintry precipitation remains back along the Alleghenies in the form of scattered snow showers. Forecast lows drop into the 20s with light winds and continued cloud cover. An active high-amplitude pattern continues into the weekend as an upper low drops down from Manitoba toward the Great Lakes. The parent upper low crosses far southern Ontario by Saturday while trailing jet energy digs through the Midwest. This positive-tilted trough shifts toward interior New England down through the Ohio Valley on Saturday night. How this feature evolves and tracks toward the Mid-Atlantic will eventually dictate what snow threats will emerge starting late Saturday night. At this point, a number of 00Z models show some accumulations reaching areas east of the Blue Ridge into the metros. Stay tuned but there does appear to be an increasing signal of accumulating snows heading into early Sunday. Ahead of this possible system, Saturday provides the mildest day of the period. Mild is all relative given the forecast is still around 5 degrees below average for mid-December. High temperatures will range from the upper 30s to mid 40s, with mid 20s to mid 30s in the mountains. Skies turn overcast by nightfall with low temperatures falling into the upper teens to 20s. Along the Alleghenies, single digits are more likely. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... The long term period will start out primarily dry as surface high pressure moves over the mid-atlantic. The exception will be upslope snow showers possible along the Alleghenies. As a cold airmass moves overhead, well below temperatures can be expected Sunday and Monday. High temperatures top out in the mid 30s each day with higher elevations staying in the teens and 20s. Warmest wind chills on Sunday will rise into the mid teens to lower 20s with the Alleghenies staying in the negatives. Overnight low temperatures will be in the teens to single digits. Cold conditions continues to be the main theme on Monday as a Canadian airmass moves over the east coast. High temperatures will be in the 20s to low 30s with the Alleghenies staying in the teens. Overnight low temperatures will drop into the teens. Dry conditions continue Tuesday as temperatures begin to moderate. High temperatures will be in the 30s to low 40s with overnight lows in the 20s. Precipitation chances increase Wednesday night as high pressure shifts offshore and return flow ushers in increased moisture. Additionally, a warm front tracking across the western portions of the area will bring mountain rain showers earlier in the day. High temperatures will be the warmest of the long term with highs in the upper 30s to mid 40s. Overnight lows will be in the 30s across the area. && .AVIATION /14Z THURSDAY THROUGH MONDAY/... VFR conditions are expected through tonight behind the exiting clipper system. A blustery west to northwesterly will impact all terminals through sundown today with gusts to around 25 to 30 knots. Expect winds to diminish through the night as weak high pressure builds in. The next system in the chain tracks south of the local area on Friday. Some light snow accompanies this feature, particularly down toward I-64 near KCHO. To the north, increased cloud cover could yield some restrictions. Gradients are weaker which keeps winds around 10 knots or less. VFR conditions are likely on Saturday with west to southwesterly wind gusts to around 10 to 15 knots. Clouds increase into the evening and night ahead of the next weather maker. This system could bring accumulating snow to the area by late Saturday night. Regardless of winter threats, low ceilings should favor restrictions overnight. Low ceilings may lead to flight restrictions on Sunday with VFR conditions returning by Sunday afternoon. Northwest winds gust 20 to 30 knots across the terminals Sunday before diminishing slowly overnight. VFR conditions continue on monday with north west winds gusting around 15 knots in the morning before becoming light. && .MARINE... Behind the exiting clipper system, a blustery west to northwesterly wind will persist through much of the day. Small Craft Advisories are in place across the waters through early this evening given the expectation of 20 to 30 knot gusts. These SCAs may need to be extended through much of the overnight. Weaker gradients set up over the waters on Friday and Saturday which should keep the area advisory-free until later in the weekend. Overall wind fields will largely be out of the west to southwest. Northwest winds gust 20 to 30 knots over the waters on Sunday in the wake of a cold front. These could intensify through the second half of Sunday into early Monday which may support gale conditions. Small Craft Advisories are likely throughout the day and through Monday morning. However, this may come with gales over portions of the waters during this period. Winds diminish as surface high pressure builds over the waters with sub SCA criteria winds expected Monday afternoon. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...Small Craft Advisory until 6 PM EST this evening for MDZ008. VA...None. WV...None. MARINE...Small Craft Advisory until 6 PM EST this evening for ANZ530>543. && $$ SYNOPSIS...BRO NEAR TERM...BRO/KJP SHORT TERM...BRO LONG TERM...AVS AVIATION...AVS/BRO MARINE...AVS/BRO ####018007948#### FXUS63 KJKL 111437 CCA AFDJKL AREA FORECAST DISCUSSION National Weather Service Jackson KY 845 AM EST Thu Dec 11 2025 .KEY MESSAGES... - A clipper system is on track to produce a widespread and impactful accumulating snow tonight into Friday morning. A Winter Weather Advisory is in effect for this system over much of eastern Kentucky. - Another light to moderate snowfall is increasingly likely Saturday night and early Sunday. - An arctic airmass with well below normal temperatures moves into our region for Sunday. && .UPDATE... Issued at 845 AM EST THU DEC 11 2025 Winter Weather Advisories were cancelled as the substantive snow showers have departed. Forecast remains largely on track. Expect more clouds than sun today with high temperatures mainly in the low to mid 30s. && .SHORT TERM...(This afternoon through Friday evening) Issued at 620 AM EST THU DEC 11 2025 Snow showers are diminishing from the northwest this morning as any Great Lakes moisture fetch is cut off, the low levels dry out, and cold air advection wanes behind last evening's cold front. Any additional roadway impacts from the departing activity will likely be confined largely to elevations above 1,500 feet. Temperatures are in the lower 30s across most of the area, except generally in the 20s above 1,500 feet. The latest weather maps show the cold front sliding off the Atlantic Seaboard while deep 500 hPa troughing is in place over the eastern CONUS around an ~502 dam parent low over the Ottawa Valley. A ridge of high pressure runs along the Mississippi River. Well upstream, a low is developing in the lee of the Rockies over Montana and Alberta, under robust vort max energy. That energy, along with its weak surface reflection, will dive southeast into the aforementioned 500 hPa trough today, crossing eastern Kentucky late tonight and Friday. A vast majority of the system's precipitation will be induced by isentropic upglide on the front end of the system. Model guidance consistently shows a WAA precipitation band developing out ahead of the low center and propagating southeast from the Dakotas, Upper Midwest, and Lower/Central Ohio Valley, leaving an ~150 to 200 mile wide northwest to southeast-oriented swath of light to moderate snow accumulation. Model guidance has been consistent in showing light to moderate snow amounts over the Big Sandy Basin and north of the Mountain Parkway near the center of the band, with more uncertainty further south and west due to potential shifts in the band's track and limited access aloft to the DGZ leading to low SLRs or even some light mixed precipitation. As the low moves through, precipitation appears to largely come to an end on Friday morning, and the system's cold front will bring little in the way of fanfare and only a subtle push of colder air late in the day. The Winter Weather Advisory for this system was extended further south to capture those counties favored to average at least 1 inch of snow accumulation, roughly coincident with the 11/00z HREF PMM snowfall. In sensible terms, look for leftover snow showers to taper to flurries between ~7 to 8 AM over southeast Kentucky. Clouds remain prevalent for much of the day, and it stays cool with highs only in the lower to middle 30s. Snow quickly develops from west to east after sunset this evening (~7 to 10 PM), while temperatures settle back into the upper 20s to lower 30s. The snow will gradually taper from southwest to northeast later in the night and on Friday morning (maybe ending as a brief mix). Snow is likely to persist longest in the northeast, likely leaving the highest amounts (2-4 inches) north of the Mountain Parkway and over the Big Sandy River Basin, dwindling to little in the vicinity of Lake Cumberland. Even once precipitation tapers on Friday, clouds remain persistent. It will overall be milder, though, with high temperatures ranging from the mid 30s in the north to near 50 along the TN/KY border. .LONG TERM...(Friday night through Wednesday) Issued at 416 AM EST THU DEC 11 2025 The extended forecast window opens with lingering, post-frontal upslope snow showers stemming from Fridays preceding clipper system. Weak surface high pressure is forecast to build into the area, but this will be very short-lived as extended model guidance and associated ensembles remain in strong agreement and maintain consistency regarding a subsequent fast-moving clipper system. This second system is projected to track across the central CONUS, reaching the CWA vicinity by late Saturday night into Sunday. Very few significant changes have occurred with respect to the temporal and spatial components of this incoming feature. The PoP is expected to increase Saturday afternoon. This system is generally forecast to maintain a more northerly track. With this northerly trajectory, the heaviest precipitation is concentrated north of the CWA, primarily along and north of the Ohio River. However, of note, some model trends suggest a potential southward shift in the track, and a few guidance runs have hinted at this possibility. This potential shift would have significant consequences on anticipated snowfall totals, the placement of the freezing line, and which areas receive frozen versus liquid precipitation. Nonetheless, the highest snow accumulations are currently forecast along and north of a line from Powell to Pike Counties through Sunday morning, but this delineation could change should the feature shift north or south. Unseasonably cold surface high pressure will subsequently build into the region behind the departing low-pressure system on Sunday, advecting some of the coldest air of the season thus far through the early part of the succeeding week. A gradual warming trend is expected by the middle of next week, preceding the approach of another synoptic system for Wednesday. In summary, the period will be characterized by the passage of two distinct clipper systems. Lingering post-frontal snow showers will initiate the period from the first clipper, and a second fast-moving clipper is forecast for Saturday night into Sunday. There remains some uncertainty regarding total snowfall accumulations with the Saturday/Sunday system, but at a minimum, the issuance of Winter Weather Advisories will be necessary to cover this expected event. Strong surface high pressure will subsequently establish itself over the region on Sunday, driving minimum temperatures down to the upper single digits and mid-teens. A notable warm advection regime ahead of the next system is forecast to commence by Wednesday. && .AVIATION...(For the 12Z TAFS through 12Z Friday morning) ISSUED AT 747 AM EST THU DEC 11 2025 MVFR ceilings, with a few breaks possible at times, will persist through the day. Another fast-moving clipper low will bring a period of steady snow tonight leading to deteriorating conditions this evening and early overnight. The worst conditions (IFR or worse) are anticipated over the northeastern half of the CWA, including JKL, SJS, and SYM. The precipitation will be lightest and of shortest duration near Lake Cumberland and heaviest and persistent north of the Mountain Parkway. Winds will be westerly at less than 10 kts today becoming light variable to southerly tonight. && .JKL WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory from 7 PM this evening to 10 AM EST Friday for KYZ044-050>052-058>060-068-069-088-104-106>115- 118>120. && $$ UPDATE...GEERTSON SHORT TERM...GEERTSON LONG TERM...VORST AVIATION...GEERTSON