textproduct: Charleston

WHAT HAS CHANGED

Confidence continues to increase in an impactful winter storm this weekend.

KEY MESSAGES

1.) Light snow transitioning to rain across the lowlands today under warm advection and gusty winds. Light snow accumulations possible in the mountains.

2.) Mainly dry cold front Thursday night, much colder Friday.

3.) Confidence is increasing in a significant winter storm this weekend. Widespread travel impacts are likely.

4.) Bitterly cold temperatures return early next week with lows in the single digits.

DISCUSSION

KEY MESSAGE 1...

A quick moving clipper system affect the region today into tonight and southerly to southwesterly flow is increasing in response this morning. Warm advection should yield rapidly rising temperatures this morning from the low teens right now to the upper 40s or even lower 50s by this afternoon.

Moisture with this system will be somewhat limited with perhaps a tenth of an inch of QPF. Relatively dry low levels will initially lead to virga, but the column will saturate from the top down by midday. Thermal profiles at Charleston and Huntington show a minimal warm nose aloft, suggesting precipitation will begin as light snow or a rain/snow mix before transitioning to all rain this afternoon as the boundary layer warms above 32F. Could see a few pockets of freezing rain where cold air hangs on if the precipitation can get in early enough. Will monitor trends this morning to see if an SPS may be warranted.

Across the Northeast Mountains and higher elevations, the column remains sub-freezing through the afternoon, supporting an all-snow forecast. However, model soundings at Snowshoe indicate a loss of ice nuclei within the cloud deck this evening as moisture becomes shallow and restricted to levels warmer than -10 C. This could support a period of very light freezing drizzle, although typically mechanical forcing ends up pushing this toward snow over freezing drizzle - even if freezing drizzle does materialize impacts are not expected with very light accumulations. Snow accumulations of 1 to 2 inches are possible in the Northeast Mountains, with only a light dusting in the northern lowland counties of southeast Ohio and northern West Virginia.

KEY MESSAGE 2...

Another quick moving disturbance moves through Thursday night into Friday. Central guidance does depict some low end pops with this, but would lean toward a dry forecast. Much colder temperatures will arrive behind this front on Friday as an expansive Arctic airmass nudges into the region.

KEY MESSAGE 3...

The primary forecast challenge for this forecast period is the major winter storm expected Saturday through Sunday. This is a classic Miller B setup involving the interaction of a moisture- rich southern stream system with an entrenched Arctic boundary.

While ensemble solutions are apparently tightening on the track and timing, the impulse responsible for this system will not round the base of a cutoff low near the Baja California coast until Thursday, leaving plenty of wiggle room for track and timing shifts over the next few runs. Moderate confidence exists that this will be an all-snow event for our forecast area, although with aforementioned wiggle room could certainly see the H850 0C line migrating a little farther north into our forecast area.

Current central guidance snow accumulation spreads remain wide, with 10th to 90th percentile ranges spanning 0 to 12 inches across southeast Ohio and 2 to 20 inches across the southern coalfields. The interquartile spread (a more general 4 to 8 north and 5 to 15 south) is a bit tighter reflecting warning criteria at the low end threshold. Given trends in operational models and ensemble members, would expect at least the interquartile range to tighten up substantially today. The heaviest snowfall is currently timed for late Saturday night through Sunday. Nationally coordinated Winter Storm Watches for at least portions southern/central Appalachians will likely be issued within the next 24 hours.

KEY MESSAGE 4...

Arctic air settles in behind the weekend storm. High temperatures on Monday will struggle to reach 30F. Backside northwesterly flow may support light lake-enhanced snow showers or flurries into Monday morning before trajectories shift to the west. With snow cover on the ground, a very dry airmass and high pressure settling overhead, Tuesday morning could be frigid.

AVIATION /06Z WEDNESDAY THROUGH SUNDAY/

VFR conditions prevail this morning with clear skies and light winds. A brief period of low level wind shear is possible through 15Z as a 40KT southwesterly jet at H850 passes overhead while surface winds remain light. Southerly winds will increase and become gusty after 15Z, with gusts of 15 to 25KTs likely at all terminals.

Ceilings will deteriorate from west to east between 16Z and 20Z as light rain and snow showers arrive. Expect a transition from VFR to MVFR ceilings, with brief IFR visibility possible in heavier showers. IFR ceilings are expected to develop at KCRW, KHTS, and KPKB after 00Z Thursday as the cold front approaches and low-level moisture remains trapped.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z THURSDAY... FORECAST CONFIDENCE: High. ALTERNATE SCENARIOS: None. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.

DATE WED 01/21/26 UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17 EST 1HRLY 01 02 03 04 05 06 07 08 09 10 11 12 CRW CONSISTENCY H H H H H H H H H H H H HTS CONSISTENCY H H H H H H H H H H H H BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY H H H H H H H H H H H H PKB CONSISTENCY H H H H H H H H H H H H CKB CONSISTENCY H H H H H H H H H H H H

AFTER 06Z THURSDAY... MVFR to IFR ceilings persist into Thursday morning with light snow showers, mainly in the mountains. A significant winter storm will bring widespread IFR to LIFR conditions in heavy snow Saturday night through Sunday.

RLX WATCHES/WARNINGS/ADVISORIES

WV...None. OH...None. KY...None. VA...None.