-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRLX 141809
AFDRLX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
209 PM EDT MON APR 14 2014

.SYNOPSIS...
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STRONG COLD FRONT TONIGHT AND EARLY TUESDAY. HIGH PRESSURE IN
CONTROL TUESDAY INTO THURSDAY. LOW PRESSURE APPROACHES FROM THE
WEST FRIDAY.
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&&

.NEAR TERM /THROUGH TUESDAY/...
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AN AREA OF SHOWERS CONTINUES TO PUSH NORTHEAST ACROSS THE AREA
THIS AFTERNOON. GUSTY SOUTHERLY WINDS WERE THE RULE...WITH GUSTS
TO 35 MPH POSSIBLE.

EXPECT THIS TREND WILL CONTINUE INTO THE EARLY EVENING
HOURS...WITH DRY CONDITIONS EXPECTED ACROSS PORTIONS OF THE WV
LOWLANDS.

A STRONG COLD FRONT WILL PUSH SLOWLY EAST ACROSS THE REGION
TONIGHT INTO EARLY TUESDAY. EXPECT WIDESPREAD PRECIPITATION WILL
DEVELOP THIS EVENING AND THEN CONTINUE INTO LATE TONIGHT. A FEW
THUNDERSTORMS MAY BE POSSIBLE ALONG AND AHEAD OF THE FRONT...WITH
THE THREAT OF SEEING A STORM DECREASING WITH THE LOSS OF HEATING
THIS EVENING.

HIGH PRESSURE WILL THEN BEGIN TO BUILD INTO THE AREA TUESDAY...
WITH THE PRECIPITATION COMING TO AN END FROM THE WEST. GUSTY NW
WINDS WILL BRING IN MUCH COLDER AIR AND AS A RESULT...HAVE CHANGED
THE PRECIP TO SNOW ACROSS THE HIGHER ELEVATIONS AFTER 16Z TUESDAY.
WOULD NOT BE TOO SURPRISED TO SEE A FEW SNOWFLAKES MIX IN ACROSS
THE LOWLANDS AS WELL.

TEMPS FOR TONIGHT AND TUESDAY ARE QUITE TRICKY AS LATEST MOS
NUMBERS ALL SUGGEST THE LOWS TONIGHT WILL OCCUR AFTER 13Z...WITH
TEMPS POSSIBLY SLOWLY FALLING MOST OF THE DAY ON TUESDAY. THIS
WILL ESPECIALLY BE TRUE ACROSS THE HIGHER ELEVATIONS WHERE TEMPS
AT SUNRISE COULD BE IN THE 50S...WITH TEMPS FALLING INTO THE 20S
BY LATE IN THE DAY.

HAVE GENERALLY GONE WITH TEMP TRENDS FOR TONIGHT AND TUESDAY
CLOSER TO THOSE SHOWN BY THE MET GUIDANCE...AS I FEEL THE HOURLY
MAV TEMPS ARE TOO WARM FOR LATE TONIGHT AND TUESDAY.
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&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
GOOD MODEL AGREEMENT ON TIMING OF THE STRONG COLD FRONT EXITING THE
MOUNTAINS EARLY TUESDAY MORNING...FOLLOWED BY MOSTLY FALLING
TEMPERATURES DURING THE DAY. POST FRONTAL PRECIPITATION WILL END
FROM WEST TO EAST DURING THE DAY...WITH MODELS ALSO AGREEING ON THE
EXIT TIMING OF THE DEEPER MOISTURE AND PRECIP WITH THE SYSTEM. BY
DAYS END ONLY A SLIGHT CHANCE WILL LINGER IN THE NORTHERN
MOUNTAINS...ENDING BY MIDNIGHT.

THE BIG CHALLENGE IS THE NON DIURNAL TEMPERATURE CURVE DURING
TUESDAY...IN THE VERY STRONG COLD ADVECTION AND UNUSUALLY COLD
AIRMASS FOR THIS TIME OF YEAR...AND THUS THE PROSPECTS OF RAIN TO
SNOW. GIVEN THE COLD MODEL CONSENSUS ALOFT WHICH WOULD SUPPORT A
CHANGEOVER TO SNOW FROM WEST TO EAST TOWARD THE END OF THE
PRECIPITATION...THE ISSUE WILL BE THE BOUNDARY LAYER TEMPERATURES.
MODELS DO SHOW STRONG TEMPERATURE FALLS IN THE MORNING AND TENDING
TO LEVEL OUT FOR A TIME IN THE LOW LANDS IN THE AFTERNOON...BEFORE
FALLING AGAIN TUESDAY NIGHT. THIS IS REASONABLE FOR THIS TIME OF
YEAR...AND ESPECIALLY IN THE WEST AND CENTRAL AS PRECIPITATION ENDS
EARLIER IN THE DAY. WILL GO WITH THE NAM MOS GUIDANCE...MAINLY
BECAUSE IT BEST SHOWS A BREAK IN THE TEMPERATURE FALLS DURING THE
AFTERNOON...ESPECIALLY WEST AND CENTRAL. THUS...BELIEVE ANY
MIX/CHANGEOVER TO SNOW IN THE LOW LANDS WILL BE BRIEF BEFORE THE
PRECIPITATION ENDS WITH NO ACCUMULATIONS...AS SURFACE TEMPERATURES
WILL STILL BE ABOVE FREEZING AND THE GROUND QUITE WARM. IN THE
CENTRAL AND NORTHERN MOUNTAINS...THERE WILL BE A CHANGEOVER TO SNOW
DURING THE AFTERNOON...BUT ACCUMULATIONS WILL LIKELY BE AN INCH OR
LESS AND MOSTLY CONFINED TO THE HIGHER ELEVATIONS. LOOK FOR
TEMPERATURES TO START OUT TUESDAY MORNING IN THE 50S EAST AND NEAR
40 FAR WEST...REACHING BY EVENING THE LOW TO MID 30S MOST OF THE LOW
LANDS AND BELOW FREEZING ABOVE 2000 FEET.

WHILE SNOW SHOWERS TAPER OFF EARLY TUESDAY NIGHT IN THE MOUNTAINS...
CLEARING FOLLOWS MORE SLOWLY WITH THE COLD ADVECTION AND UPSLOPE
FLOW IN THE MOUNTAINS. STILL...IT SHOULD BECOME MOSTLY CLEAR EARLY
ENOUGH AS DRY HIGH PRESSURE BUILDS IN RAPIDLY FROM THE WEST...AND
ALLOW TEMPERATURES TO FALL WELL BELOW FREEZING IN ALL LOCATIONS.
HOWEVER...BELIEVE THE MODELS MAY BE A BIT ON THE LOW SIDE AS THEY
FORECAST A RUN FOR RECORD LOWS TUESDAY NIGHT. FOR NOW...WILL KEEP
OUR MINS A COUPLE OF DEGREES ABOVE THE MOS...BUT STILL WELL BELOW
FREEZING.

THEREAFTER...HIGH PRESSURE SLIDES ACROSS WITH ABUNDANT SUNSHINE
WEDNESDAY AND THURSDAY...ALONG WITH A WARMING TREND. WITH DRY AIR
AND LIGHT WINDS WEDNESDAY NIGHT...TEMPERATURES COULD FALL BELOW
FREEZING AGAIN.

&&

.LONG TERM /FRIDAY THROUGH SUNDAY/...
SW FLOW DOMINATES THROUGH FRIDAY BEFORE S/W TROF TRIES TO CREATE FOR
AN UNSETTLED SATURDAY. DUE TO CONTINUED DIFFERENCES REGARDING
AMPLITUDE AND STRENGTH OF SURFACE FEATURES...HAVE STAYED CLOSE TO
WPC PREFERRED SOLUTION WITH THREAT FOR SHRA FRIDAY NIGHT AND
SATURDAY.

FOR TEMPS...A WARMING TREND WILL BE NOTED TO ROUND OUT THE WORK
WEEK...BEFORE COOLER BUT MORE SEASONAL AIR ARRIVES FOR THE WEEKEND.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
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SHOWERS CONTINUE TO MOVE NORTHEAST ACROSS PORTIONS OF THE REGION.
VFR CONDITIONS ARE GENERALLY THE RULE IN MOST LOCATIONS. HOWEVER...MVFR
CONDITIONS MAY PREVAILO IN THE HEAVIER SHOWERS.

THE SHOWERS WILL CONTINUE TO MOVE NORTHEAST THIS AFTERNOON WITH
DRY CONDITIONS EXPECTED ACROSS MUCH OF THE SOUTHERN AND CENTRAL
LOWLAND COUNTIES OF WEST VIRGINIA BETWEEN 20Z AND 02Z.

TSRA POSSIBLE AND TONIGHT...BUT DO NOT FEEL THEY WILL BE
PREVAILING...SO HAVE OPTED FOR THE VCTS/CB CODING IN THE TAFS.

A COLD FRONT WILL SLOWLY PUSH EAST ACROSS THE REGION TONIGHT INTO
EARLY TUESDAY...EXPECT THE FRONT TO PUSH INTO SOUTHEAST OHIO BY 03Z...
CROSS THE OHIO RIVER 06Z-08Z AND THEN PUSH EAST OF THE MOUNTAIN
COUNTIES AFT 13Z.

EXPECT PRECIPITION WILL BECOME MORE WIDESPREAD AS FRONT PUSHES
EAST. IN ADDTION...IFR CONDITIONS SHOULD SPREAD EAST ALONG AND
BEHIND THE FRONT.

TSRA POSSIBLE AND TONIGHT...BUT DO NOT FEEL THEY WILL BE
PREVAILING...SO HAVE OPTED FOR THE VCTS/CB CODING IN THE TAFS.

SOUTHERLY WINDS WILL PREVAIL AHEAD OF THE FRONT...WITH OCCASIONAL
GUSTS TO 30KT THRU 23Z. A SHIFT TO THE WEST NORTHWEST CAN BE THEN
EXPECTED BEHIND THE FRONT...WHICH WILL PASS TONIGHT. GUSTY NW
WINDS TO 20 KT SHOULD BE THE RULE AFT 13Z TUE.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z TUESDAY...

FORECAST CONFIDENCE: MEDIUM.

ALTERNATE SCENARIOS: CONVECTION TIMING AND BRIEF FLIGHT CATEGORY
BOUNCES COULD LEAD TO TEMPOS AND AMENDMENTS. MAY NEED PREVAILING
TSRA.

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       18   19   20   21   22   23   00   01   02   03   04   05
EDT 1HRLY       14   15   16   17   18   19   20   21   22   23   00   01
CRW CONSISTENCY  H    H    H    H    H    H    H    M    M    M    M    M
HTS CONSISTENCY  H    H    H    H    H    H    M    M    M    M    M    M
BKW CONSISTENCY  H    H    H    H    H    H    H    M    M    M    M    M
EKN CONSISTENCY  H    H    H    H    H    H    H    M    M    M    M    M
PKB CONSISTENCY  H    H    H    H    H    H    M    M    M    M    M    M
CKB CONSISTENCY  H    H    H    H    H    H    H    M    M    M    M    M

AFTER 18Z TUESDAY...
IFR CONDITIONS POSSIBLE IN SNOWSHOWERS IN WV MOUNTAINS EARLY TUESDAY
NIGHT.
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&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.

&&

$$
SYNOPSIS...JSH/KTB/26
NEAR TERM...JSH
SHORT TERM...JMV
LONG TERM...30
AVIATION...JSH