-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRLX 161839
AFDRLX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
239 PM EDT THU MAY 16 2013

.SYNOPSIS...
STATIONARY FRONT STALLS OVER THE AREA TODAY INTO THE WEEKEND.
UPPER LEVEL SHORTWAVE PASSES SOUTH. NEW FRONT APPROACHES NEXT
WEDNESDAY.

&&

.NEAR TERM /THROUGH FRIDAY/...
COVERAGE INCREASE IN THE CONVECTION OCCURRING OVER THE LAST HOUR
OR SO AND NOW HAS THE I-64 CORRIDOR IN ITS SIGHT. CONVECTION WILL
WANE THIS EVENING...BUT WILL NOT NECESSARILY CEASE COMPLETELY
OVERNIGHT...WARRANTING THE SLIGHT CHANCE POPS THROUGH LATE
TONIGHT. COULD SEE SOME LATE FOG IF THE SKY CLEARS OVER SATURATED
GROUND.

NONE OF THE SHORT TERM MODELS HAVE BEEN STELLAR IN DEFINING THE
PROPER LOCATION OF FORCING...AS RADAR TRENDS SHOW THE CURRENT
BANDS OF SHOWERS AND STORMS LARGELY SOUTH OF THEIR PROGGED AREAS.
NAM IS NOT TOO BAD AND NEITHER IS THE RAP...BUT IT SEEMS LIKE
SOLUTIONS DESCEND INTO CHAOS EVEN A FEW HOURS BEYOND THE 18Z
FORECAST GIVING LITTLE CONFIDENCE INTO THE OVERNIGHT PROGS. IT
MAY BE A SITUATION WHERE THE TIMING OF THE MODELS IS JUST OFF BY
3 HOURS OR SO.

AGAIN...DO FEEL THE CONVECTION IS PARTIALLY DIURNALLY FORCED. AS
MENTIONED EARLIER...DO SEE THE POSSIBILITY OF PARTIAL CLEARING
LATE TONIGHT.

DO NOT SEE A LOT OF PROGRESS TO BE MADE WITH THE FRONT INTO
FRIDAY...AND WILL STILL BE OSCILLATING LIKELY JUST NORTH OF THE
OHIO RIVER.

WILL NEED TO WATCH TRAINING AREAS OF RAINFALL OVER THE NEXT COUPLE
OF DAYS. SO FAR...RAIN GAGE AMOUNTS ARE MODEST IN TERMS OF
MEASURED PRECIPITATION. ACROSS THE THE NORTHERN ZONES IS ON THE
DRIER SIDE TO BEGIN WITH...SO WILL CONTINUE MENTIONING WORDING IN
THE HWO.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
-- Changed Discussion --
MODELS HAVE COME INTO BETTER AGREEMENT THIS PERIOD WITH A WEAK UPPER
LOW DRIFTING EASTWARD ACROSS THE OHIO AND TENNESSEE VALLEYS THROUGH A
BUILDING EASTERN U.S. UPPER RIDGE. WHILE THERE ARE SOME PLACEMENT
AND SPEED DIFFERENCES WITH THIS WEAK UPPER FEATURE...THERE LOOKS TO
BE A BROAD CIRCULATION OF WARM AND RELATIVELY MOIST AND UNSTABLE AIR
OVER THE AREA THROUGH SUNDAY. GIVEN THAT THE FRONT MEANDERING ACROSS
THE AREA WILL BE HARD TO FIND BY SUNDAY...WILL FOCUS POPS IN A
DIURNAL NATURE ACROSS THE AREA WITH HIGHEST POPS ON SATURDAY
AFTERNOON. WILL STILL CONTINUE A CHANCE OF CONVECTION ON
SUNDAY...BUT MAINLY IN THE EAST AND IN THE AFTERNOON...AS THE UPPER
SYSTEM SHOULD START TO EXIT TO THE EAST. TEMPERATURES WILL NOT
CHANGE MUCH FROM DAY TO DAY OR EVEN NIGHT TO NIGHT AS WE CONTINUE IN
A RATHER CLOUDY AND MOIST PATTERN. TEMPERATURES LOOK TO BE NEAR
NORMAL.
-- End Changed Discussion --

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
-- Changed Discussion --
EXTENDED PERIOD BEGINS WITH CWA IN NE PORTION OF AN UPPER
RIDGE...HOWEVER A SW TROUGH RESIDES ON ERN PERIPHERY OF THIS RIDGE
AND IS SLOW TO PUSH EAST. THIS SHOULD KEEP OUR AREA IN DISTURBED
WEATHER THROUGH DAY 4...WITH PRIMARILY DIURNALLY DRIVEN SHOWERS AND
THUNDERSTORMS IN THE WV MOUNTAINS. LITTLE BREAK...IF ANY...IN THE
AGITATED WEATHER PATTERN AS NEXT SYSTEM IS QUICK TO MOVE IN FROM
THE WEST TUESDAY. GFS AND ECMWF DIVERGE SOLNS WITH THE HANDLING OF
THE UPPER LEVEL LOW TRACK THROUGH THE GREAT LAKES. RELUCTANT TO GO
ANY HIGHER THAN CHC POPS WITH TIMING DIFFERENCES BETWEEN OPERATIONAL
GUIDANCE. STAYED NEAR WPC GUIDANCE WITH TEMPS THROUGH THE EXTENDED
SAVE FOR LOCAL ADJUSTMENTS.
-- End Changed Discussion --

&&

.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
CONVECTION COVERAGE INCREASING AREA WIDE THIS AFTERNOON...MAKING
FOR A COMPLICATED AVIATION FORECAST. ATTEMPTED TO KEEP THE TAFS AS
SIMPLE AS POSSIBLE...WITH MINIMAL TEMPOS...BUT DO EXPECT RAPIDLY
CHANGING CONDITIONS AT PLACES LIKE CRW AND HTS. REMOVED SOME OF
THE IMMEDIATE TERM THUNDER THREATS OVER THE NORTHERN TERMINALS AT
PKB/CKB/EKN...AND CARRY SHOWERS IN THESE AREAS THROUGH THE
REMAINDER OF THE DAY. THUNDER EXPECTED AT BKW LATER THIS
AFTERNOON.

CONVECTION WANES LATER THIS EVENING...BUT MAY NOT COMPLETELY CEASE
OVERNIGHT. THAT BEING SAID...WILL KEEP PREVAILING VFR...BUT
DESCENDING INTO MVFR/IFR AS MIST AND FOG COULD SETTLE IN
LATE...AFTER 06Z. THIS WILL BE DEPENDENT ON THE ABILITY OF THE SKY
TO CLEAR SOME WITH THE WET SURFACE IN PLACE.

ROUNDS OF CONVECTION RETURNS WITH HEATING FRIDAY.

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

FORECAST CONFIDENCE...MEDIUM

ALTERNATE SCENARIOS: MAY NOT HAVE BRIEF IFR COVERED ENOUGH IN
TAFS. FOG DEVELOPMENT TONIGHT IS NOT A CERTAINTY.

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  M    M    M    M    M    M    M    H    H    H    H    H
HTS CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
BKW CONSISTENCY  M    M    M    M    M    M    M    H    H    H    H    H
EKN CONSISTENCY  H    H    H    H    H    H    H    H    H    M    M    L
PKB CONSISTENCY  H    H    H    H    H    H    M    H    H    H    H    H
CKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H

AFTER 18Z FRIDAY...
BRIEF/INTERMITTENT IFR POSSIBLE IN HEAVIER SHOWERS/THUNDERSTORMS
THROUGH THE WEEKEND.

&&

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

&&

$$
SYNOPSIS...JMV/26/TAX
NEAR TERM...26
SHORT TERM...JMV
LONG TERM...TAX
AVIATION...26