National Weather Service Text Product Display

Area Forecast Discussion
Issued by NWS Charleston, WV

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000
FXUS61 KRLX 170808
AFDRLX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
408 AM EDT MON JUN 17 2013

.SYNOPSIS...
DRIER IN THE MID AND UPPER LEVELS TODAY. ANOTHER DISTURBANCE
PASSES TUESDAY.

.NEAR TERM /THROUGH TONIGHT/...
MODELS ARE A BONA FIDE MESS DEALING WITH THE MYRIAD OF UPPER LEVEL
DISTURBANCES THROUGH THE NEAR TERM FORECAST...AND THE TIMING OF
SUCH FEATURES WITH SOME DIFFERENCES WITHIN THESE OPERATIONAL
MODELS. ALSO DEALING WITH A SURFACE BOUNDARY/WEAK COOL FRONT THAT
WILL SLOWLY DROP IN FROM THE NORTH DURING THIS TIME...ALTHOUGH
WILL BE HARD TO DISTINGUISH AT ANY GIVEN POINT DURING THE DAY. THE
BEST APPROACH IN THIS CASE IS TO TRY TO FIND EITHER STABILITY OR
LACK OF SUFFICIENT MOISTURE DEPTH IN CONSTRUCTING THE POPS RATHER
THAN TO TRY TO LATCH ON TO SPECIFIC FEATURES.

NAM IS SHOWING SIGNIFICANT DRYING TODAY THROUGH THE MID AND UPPER
LEVELS OF THE ATMOSPHERE...LEADING TO MORE OF A CUMULUS FIELD WITH
SOME VERTICAL EXTENT...BUT POPS ON THE LOW SIDE WITHOUT MUCH ABOVE
AROUND 825MB THROUGH THE MAIN HEATING OF THE DAY. VERTICAL
PROFILES WILL TIGHTEN UP IN TERMS OF THE T/TD SPREAD TOWARDS
DAWN...ESPECIALLY ACROSS THE SOUTH WHERE MODELS ARE AT LEAST
CONSISTENT IN THE PLACEMENT OF A STRONGER MID/UPPER LEVEL WAVE
EVEN THOUGH THE TIMING IS OFF. WILL RIDE WITH SLOWER NAM PER
COLLABORATION WITH RNK TONIGHT...BUT STILL CARRYING CHANCE BY 12Z
TUESDAY.

LACK OF HIGH POPS TODAY WILL GIVE AREA WATERSHEDS SOME TIME TO
RECOVER. HAVE HAD STOUT RAIN OVER THE SOUTHERN COAL FIELDS IN THE
PAST 24 HOURS...AND THE CENTRAL CWA/ROANE STILL DEALING WITH
ISSUES FROM THIS PAST WEEK. 3 HOUR FFG DOWN TO AN INCH AND A HALF
FOR THE EASTERN HALF OF THE CWA FOR THE MOST PART.

.SHORT TERM /TUESDAY THROUGH THURSDAY/...
-- Changed Discussion --
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.-- End Changed Discussion --

.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 /08Z MONDAY THROUGH FRIDAY/...
-- Changed Discussion --
CEILINGS TO CONTINUE TO LOWER TO MVFR AREA WIDE BEFORE DAWN...AND
WILL IMPROVE WITH MIXING AFTER 12Z TODAY. MAY GET BRIEF VISIBILITY
RESTRICTIONS UNTIL THAT TIME AS WELL...WITH ABUNDANT SURFACE
MOISTURE AND MIST/FOG TRYING TO FORM DESPITE THE BROKEN-OVERCAST
CONDITIONS. LAMP GUIDANCE KEPT THE VISIBILITIES ON THE OPTIMISTIC
SIDE HOWEVER.

BRING CEILINGS BACK TO MVFR THROUGH THE DAY TODAY. PRECIPITATION
CHANCES LOW DURING THE AFTERNOON HOURS...WITH A SLIGHT
FAVORABILITY IN THE MOUNTAINS. SHORT WAVE TROUGH TO AFFECT THE
SOUTHERN ZONES INTO TONIGHT...AND RAMP THE PRECIPITATION POTENTIAL
UP AFTER 06Z TUESDAY ACROSS THE SOUTH...WARRANTING THE VCSH
DESIGNATION AT BKW.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z TUESDAY...

FORECAST CONFIDENCE...MEDIUM.

ALTERNATE SCENARIOS: TIMING OF LOWERING OF CEILINGS COULD VARY.
MAY NEED BRIEF IFR AT PKB...HTS...OR CRW IN BRIEF CLEARING. TIMING
OF CEILINGS LIFTING TO VFR MONDAY MAY VARY.

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 MON 06/17/13
UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19
EDT 1HRLY 04 05 06 07 08 09 10 11 12 13 14 15
CRW CONSISTENCY H H H H H M M M M M M M
HTS CONSISTENCY H H H H H H M M M H M H
BKW CONSISTENCY H H H H H M M M M M M M
EKN CONSISTENCY H H H H H H H M M M M M
PKB CONSISTENCY M M M H H M M M M M M M
CKB CONSISTENCY M M M M M M M M M M H H

AFTER 06Z 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...MZ/26
NEAR TERM...26
SHORT TERM...JSH
LONG TERM...MZ
AVIATION...26

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