979
FXUS61 KRLX 261745
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
145 PM EDT SUN APR 26 2026
WHAT HAS CHANGED
ISSUED FROST ADVISORY FOR MOUNTAIN VALLEYS LATE TONIGHT INTO
MONDAY MORNING. STILL CONSIDERABLE UNCERTAINTY REGARDING STRONG
TO SEVERE STORM POTENTIAL TUESDAY MORNING, TUESDAY
AFTERNOON AND WEDNESDAY.
KEY MESSAGES
1.) STUBBORN STRATOCUMULUS WILL CLEAR THIS AFTERNOON. PATCHY
FROST AND/OR FOG IN MOUNTAIN VALLEYS TONIGHT.
2.) A DECAYING COMPLEX OF STORMS WILL BRING GUSTY WINDS AND A
THREAT FOR A DECAYING CONVECTIVE COMPLEX FROM THE WEST MONDAY
NIGHT INTO TUESDAY MORNING.
3.) ADDITIONAL STRONG TO SEVERE STORM POTENTIAL TUESDAY
AFTERNOON IS HIGHLY CONDITIONAL ON MORNING CLOUD COVER AND
PRECIPITATION.
4.) A SOUTHERN STREAM SYSTEM BRINGS BENEFICIAL RAINFALL AND A
LOW END SEVERE THREAT WEDNESDAY.
5.) COOL, NORTHWESTERLY FLOW RETURNS LATE WEEK WITH WIDESPREAD
FROST/FREEZE HIGHLIGHTS LIKELY NEXT WEEKEND.
DISCUSSION
KEY MESSAGE 1...
OBSERVATIONS EARLY THIS AFTERNOON SHOW AN EXTENSIVE
STRATOCUMULUS DECK LINGERING BETWEEN 1000 AND 2500 FEET TRAPPED
BENEATH A STRONG SUBSIDENCE INVERSION. AS DAYTIME MIXING AND DRY
ADVECTION CONTINUES, THESE CEILINGS WILL SLOWLY DISSIPATE THIS
AFTERNOON, YIELDING MAINLY CLEAR SKIES OVERNIGHT.
UNDER A DRY POST-FRONTAL AIRMASS AND LIGHT WINDS, STRONG
RADIATIONAL COOLING WILL TAKE HOLD. IN THE SHELTERED TERRAIN OF
THE NORTHEAST MOUNTAINS, TEMPERATURES ARE FORECAST TO DROP INTO
THE LOW TO MID 30S, WITH 33 TO 36 DEGREES INDICATED BY
STATISTICAL GUIDANCE ACROSS THE MOUNTAIN COOP SITES. THIS WILL
SUPPORT PATCHY FROST DEVELOPMENT IN AREAS SUBJECT TO COLD AIR
DRAINAGE. HOWEVER, VALLEY FOG IS ALSO ANTICIPATED TO DEVELOP
TONIGHT, WHICH MAY SERVE TO LOCALLY LIMIT FROST COVERAGE. GIVEN
THE POTENTIAL IMPACTS TO EARLY SEASON VEGETATION, A FROST
ADVISORY HAS BEEN ISSUED FOR THE MOUNTAIN VALLEYS LATE TONIGHT
INTO MONDAY MORNING.
KEY MESSAGE 2...
DRY CONDITIONS CONTINUE THROUGH THE DAY MONDAY WITH
TEMPERATURES REBOUNDING. BY MONDAY NIGHT, A DECAYING CONVECTIVE
COMPLEX IS FORECAST TO APPROACH FROM THE WEST. GUIDANCE HAS
TRENDED SLIGHTLY QUICKER WITH THE ARRIVAL OF THE LEADING EDGE
INTO SOUTHEAST OHIO AND NORTHEAST KENTUCKY. A STOUT 55 TO 60KT
H850 LOW-LEVEL JET WILL ACCOMPANY THIS SYSTEM, PROVIDING STRONG
KINEMATICS. WHILE THE NOCTURNAL TIMING WILL LARGELY LIMIT
SURFACE-BASED INSTABILITY, KEEPING PARCELS ELEVATED OFF THE
SURFACE, THE STRONG WIND FIELD ALOFT POSES A CONCERN. WITH TREES
NOW IN FULL OR NEARLY FULL LEAF, AND A PROTRACTED DRY PERIOD
WEAKENING SOME ROOT SYSTEMS, THE COMBINATION OF RAIN LOADING AND
GUSTY SURFACE WINDS TRANSFERRING MOMENTUM DOWNWARD COULD YIELD
LOW-END TREE DAMAGE EVEN WELL BELOW SEVERE CRITERIA.
KEY MESSAGE 3...
THE SEVERE POTENTIAL FOR TUESDAY AFTERNOON REMAINS HIGHLY
CONDITIONAL AND RIDDLED WITH UNCERTAINTY. THE PRIMARY CHALLENGES
REVOLVE AROUND THE LONGEVITY OF MONDAY NIGHT CONVECTION. IF
SHOWERS AND CLOUD COVER PERSIST DEEP INTO TUESDAY MORNING, IT
WILL SEVERELY INHIBIT TEMPERATURE RECOVERIES AND SUBSEQUENT
DESTABILIZATION, POTENTIALLY CAPPING PARCELS AT THE BASE OF THE
ELEVATED MIXED LAYER AND PREVENTING AFTERNOON THUNDERSTORM
DEVELOPMENT ENTIRELY. FURTHERMORE, THE UPSTREAM ELEVATED MIXED
LAYER PLUME MAY BE SIGNIFICANTLY OVERTURNED BY THE PRIOR
CONVECTION, ROBBING THE ENVIRONMENT OF CONDITIONAL INSTABILITY.
IT CURRENTLY APPEARS LESS LIKELY THAT THE PREVIOUSLY ANTICIPATED
LULL IN KINEMATICS WILL PERFECTLY OVERLAP WITH PEAK AFTERNOON
HEATING WHICH WOULD BOLSTER SEVERE CHANCES IF SUFFICENT
INSTABILITY MATERIALIZES AND STORMS CAN FORM. CONSEQUENTLY,
CONFIDENCE IN A TUESDAY AFTERNOON SEVERE THREAT REMAINS LOW.
KEY MESSAGE 4...
A SOUTHERN STREAM DISTURBANCE WILL APPROACH
THE REGION ON WEDNESDAY, BRINGING A MUCH-NEEDED ROUND OF
BENEFICIAL RAINFALL. FORECAST SOUNDINGS DEPICT DEEP, SKINNY
MUCAPE PROFILES, WHICH ARE HIGHLY SUPPORTIVE OF EFFICIENT
RAINFALL PRODUCTION. INSTABILITY HAS TRENDED SLIGHTLY UPWARD
FROM PREVIOUS FORECAST CYCLES. WHEN COMBINED WITH APPROXIMATELY
40KTS OF DEEP-LAYER SHEAR, A MARGINAL SEVERE THUNDERSTORM THREAT
MAY MATERIALIZE, MOST LIKELY OVER THE SOUTHERN COALFIELDS.
HOWEVER, SIMILAR TO TUESDAY, LARGE CONVECTIVE COMPLEXES
TRAVERSING THE MIDDLE OF THE COUNTRY IN THE PRECEDING DAYS COULD
SIGNIFICANTLY ALTER THE SYNOPTIC AND MESOSCALE ENVIRONMENT,
KEEPING CONFIDENCE LOW.
KEY MESSAGE 5...
FORECAST CONFIDENCE DECREASES TOWARD THE END OF THE WORK WEEK AS
MODEL SOLUTIONS DIVERGE. NONETHELESS, A GENERAL CONSENSUS
ESTABLISHES A DEEP UPPER-LEVEL TROUGH ANCHORED OVER THE
NORTHEAST, PLACING THE LOCAL AREA IN A COOL, NORTHWESTERLY FLOW
REGIME. WEAK PERTURBATIONS RIPPLING THROUGH THIS FLOW OUT OF THE
GREAT LAKES WILL MAINTAIN LOW-END CHANCES FOR PERIODIC LIGHT
SHOWERS, THOUGH SUBSTANTIAL DRY INTERLUDES ARE EXPECTED. IT IS
NOT OUT OF THE QUESTION TO SEE A FEW SNOWFLAKES MIX IN ACROSS
THE HIGHEST ELEVATIONS OF THE NORTHEAST MOUNTAINS DURING THE
DIURNAL TEMPERATURE MINIMUM ON SATURDAY MORNING.
THE PRIMARYIMPACT DURING THIS EXTENDED PERIOD WILL BE THE COOL
OVERNIGHT TEMPERATURES. FROST AND FREEZE CONDITIONS ARE LIKELY,
ESPECIALLY HEADING INTO NEXT WEEKEND, WHEN WIDESPREAD
FROST/FREEZE HIGHLIGHTS MAY BE REQUIRED.
AVIATION /18Z SUNDAY THROUGH FRIDAY/
MVFR STRATOCUMULUS CEILINGS REMAIN ENTRENCHED ACROSS MUCH OF THE
REGION EARLY THIS AFTERNOON, GENERALLY BETWEEN 1200 AND 2500
FEET AGL. DRY ADVECTION AND DIURNAL MIXING WILL ALLOW THESE
CLOUDS TO SLOWLY SCATTER OUT FROM SOUTHWEST TO NORTHEAST BETWEEN
18Z AND 22Z, BRINGING A RETURN TO PREVAILING VFR CONDITIONS.
LIGHT NORTHERLY WINDS OF 5 TO 10KT WILL BECOME CALM AFTER
SUNSET.
MOUNTAIN VALLEY FOG IS LIKELY AT EKN HEADING INTO DAYBREAK
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z MONDAY...
FORECAST CONFIDENCE: HIGH
ALTERNATE SCENARIOS: TIMING OF DISSIPATION OF MVFR CEILINGS MAY
VARY BY AN HOUR OR TWO. FOG COULD BECOME MORE DENSE THAN
FORECAST AT EKN.
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.
UTC 1HRLY 17 18 19 20 21 22 23 00 01 02 03 04
EDT 1HRLY 13 14 15 16 17 18 19 20 21 22 23 00
CRW CONSISTENCY H M 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 M H H H H H M H H H H
EKN CONSISTENCY M 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 L M H H H H H H H H H H
AFTER 18Z MONDAY...
IFR CONDITIONS POSSIBLE IN SHOWERS AND THUNDERSTORMS
LATE MONDAY/TUESDAY MORNING, THEN AGAIN TUESDAY NIGHT AND
WEDNESDAY.
RLX WATCHES/WARNINGS/ADVISORIES
WV...FROST ADVISORY FROM 3 AM TO 9 AM EDT MONDAY FOR WVZ523>526.
OH...NONE.
KY...NONE.
VA...NONE.
DISCUSSION...JP
AVIATION...JP
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page