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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRLX 171836
AFDRLX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
237 PM EDT MON JUN 17 2013

.SYNOPSIS...
-- Changed Discussion --
DRIER IN THE MID AND UPPER LEVELS TODAY THOUGH STILL SOME SCATTERED
AFTERNOON SHOWERS OR POSSIBLY A THUNDERSTORM. ANOTHER DISTURBANCE
PASSES TUESDAY BRINGING ADDITIONAL SHOWERS AND THUNDERSTORMS.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH TUESDAY/...
-- Changed Discussion --
TRICKY FORECAST WITH WARM MOIST MODERATELY UNSTABLE WSW FLOW BUT THE
LACK OF ANY WELL DEFINED FORCING MECHANISMS TO TRIGGER OR FOCUS
CONVECTION. THE VERY WEAK BOUNDARY WHICH DROPPED SOUTH ACROSS THE
FORECAST AREA THIS AFTERNOON REMAINS OVER THE SOUTHERN MOST COUNTIES
BUT OTHERWISE SUNSHINE AND OROGRAPHIC EFFECTS WILL DRIVE WHICH AREAS
HAVE A BETTER CHANCE AT SHOWERS OR THUNDERSTORMS. BASED ON THIS HAVE
GONE WITH SCATTERED COVERAGE OVER THE SOUTHERN AREAS AS WELL AS THE
EASTERN MOUNTAIN COUNTIES AND ISOLATED ELSEWHERE. THIS ACTIVITY
SHOULD TAPER OFF QUICKLY AROUND SUNSET.

POPS WILL INCREASE AGAIN FROM THE WEST OVERNIGHT AS TWO FEATURES
APPROACH THE AREA. ONE WAVE FROM THE WEST SOUTHWEST THAT WILL BRUSH
OVER THE SOUTHERN AREA AND THE FRONTAL BOUNDARY FROM THE WEST
NORTHWEST. NEITHER FEATURE IS PARTICULARLY STRONG BUT COMBINATION
FOR WILL MAKE FOR A FAIRLY DAMP DAY TUESDAY.
-- End Changed Discussion --

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
CURRENT THINKING IS THAT A COLD FRONT WILL BE LOCATED NORTH OF THE
REGION AT THE BEGINNING OF THE PERIOD.  THIS FEATURE IS EXPECTED TO
PUSH SOUTHEAST TUESDAY NIGHT AND EARLY WEDNESDAY.  A MID-LEVEL
SHORTWAVE IS ALSO EXPECTED TO PUSH SOUTHEAST ACROSS THE AREA LATE
TUESDAY NIGHT INTO WEDNESDAY.

HAVE SLOWED DOWN ONSET OF LIKELY POPS ON TUESDAY.  HOWEVER...STILL
LOOKS LIKE MEASURABLE PRECIP IS A GOOD BET ACROSS THE MOUNTAINS AS
WELL AS PORTIONS OF THE SOUTHERN COALFIELDS FOR LATER IN THE DAY.

MODELS ALSO DEVELOP MEASURABLE PRECIP TUESDAY AFTERNOON/EVENING
ACROSS OUR NORTHERN COUNTIES INVOF THE COLD FRONT AS IT PUSHES
SOUTH INTO THE AREA. IN RESPONSE...HAVE ADDED HIGH CHANCE POPS FOR
NOW. MAY NEED TO INCREASE THESE POPS TO LIKELY. HOWEVER...WILL LET
NEXT SHIFT MAKE THAT DECISION.

WEAK HIGH PRESSURE BUILDS IN TUESDAY NIGHT...WHICH SHOULD BRING
PRECIP CHANCES TO AN END.

COMBINATION OF SUFFICIENT LOW-LEVEL MOISTURE AND DAYTIME HEATING MAY
BE ENOUGH TO PRODUCE A FEW AFTERNOON AND EVENING STORMS ACROSS THE
MOUNTAIN COUNTIES WEDNESDAY AND THEN AGAIN ON THURSDAY.
SUFFICIENT.

TEMPERATURE GUIDANCE IS WARMER FOR HIGHS ON TUESDAY AND
WEDNESDAYS...SO HAVE TWEAKED NUMBERS TO REFLECT CURRENT TRENDS.

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
UPPER RIDGE OVER THE SOUTHERN PLAINS WILL INFLUENCE MOST OF THE LONG
TERM PERIOD...WITH GRADUALLY WARMING AND MOISTENING OF THE BOUNDARY
LAYER. UNFORTUNATELY...THE RIDGE LOOKS RATHER DIRTY WITH SEVERAL
VORT MAXES DROPPING DOWN THE EASTERN SIDE IN THE NW FLOW OVER THE
MID AND UPPER OHIO VALLEY/CENTRAL APPALACHIANS. THIS SPELLS AT LEAST
SOME CHANCES OF THUNDERSHOWERS FOR THE SECOND HALF OF THE WORK WEEK.
UNTIL TIMING ON INDIVIDUAL VORTS CLEARS UP...KEPT PRECIP TIED TO THE
DIURNAL CYCLE...WITH THE HIGHEST POPS IN THE AFTERNOON OVER THE
HIGHER TERRAIN. BY NEXT WEEKEND...BOTH GFS AND ECMWF ADVERTISE A
STRONGER VORT MAX FOR SATURDAY...AND WITH MORE MOISTURE IN PLACE
INCLUDED CHANCE POPS CWA-WIDE.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
-- Changed Discussion --
THE STRATUS HAS LIFTED SCATTERED TO BROKEN VFR DECK THIS AFTERNOON.
WITH LOW LEVEL MOISTURE CONTINUING TO STREAM TODAY AND TONIGHT THINK
THAT VALLEY FOG WILL ISSUE TONIGHT DESPITE THE OVERRUNNING CIRRUS
DECK. ALSO PRECIPITATION SPREADING IN FROM THE WEST LATE TONIGHT AND
TUESDAY MORNING WILL FURTHER COMPLICATE THINGS. RIGHT NOW HAVE THE
TIMING SUCH THAT THE VALLEY FOG THAT FORMS OVERNIGHT WILL MIX OUT
PRIOR TO THE ONSET OF THE NEXT ROUND OF PRECIPITATION.

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

FORECAST CONFIDENCE...LOW TO MEDIUM.

ALTERNATE SCENARIOS: MAY NOT GET THE MIST/FOG TONIGHT DUE TO HIGHER
LEVEL CLOUD COVER. ALSO MID TO LOW LEVEL STRATUS DECK MIGHT REFORM
OVERNIGHT WHICH WOULD BRING MVFR TO IFR CEILINGS BUT KEEP
VISIBILITIES HIGHER. PRECIPITATION COMING IN FROM THE WEST MAY OR
MAY NOT ALLOW FOG TO LIFT AND CONDITIONS TO IMPROVE PRIOR TO
SPREADING OVER THE AREA.

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    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  M    M    M    M    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 18Z TUESDAY...
IFR AT TIMES IN SHOWERS AND THUNDERSTORMS TUESDAY.
-- End Changed Discussion --

&&

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

&&

$$
SYNOPSIS...30/JR
NEAR TERM...JR
SHORT TERM...30
LONG TERM...30
AVIATION...JR