Area Forecast Discussion Issued by NWS Charleston, WV
000
FXUS61 KRLX 191610
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
1146 AM EDT WED JUN 19 2013
.SYNOPSIS...
HIGH PRESSURE CRUISES WEDNESDAY AND THURSDAY...BEFORE DROPPING
ANCHOR IN THE WESTERN ATLANTIC TO BEGIN THE SUMMER SEASON. HIGH
RIDGE ALOFT KEEPS DRY CONDITIONS THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
1145 AM UPDATE...STRATUS ERODING RAPIDLY SO THAT MOST OF THIS
AFTERNOON WILL SEE LOTS OF SUNSHINE AND WARM TEMPERATURES. STILL WILL
LEAVE A SLIGHT CHANCE IN THE MOUNTAINS BEFORE DRY AIR MIXES DOWN
LATER AROUND MID AFTERNOON. WILL INCLUDE LOCALLY DENSE FOG TONIGHT.
630 AM UPDATE...
SFC FRONT ROUGHLY FROM POCAHONTAS COUNTY SW-WARD TO JUST NORTH OF
BKW AT THIS TIME AND WILL CONTINUE A BIT FURTHER SOUTHWARD INTO
VIRGINIA BEFORE STALLING LATER THIS MORNING. TWEAKED SKY COVER TO
REFLECT QUICKER CLEARING ACROSS SE OHIO AND INTO ADJACENT WEST
VIRGINIA. INGESTED RECENT OBS. OTHERWISE...NO MAJOR CHANGES.
PREVIOUS DISCUSSION...
AT 06Z SFC OBS INDICATE SECONDARY FRONT LOCATED ROUGHLY FROM HTS
EAST/NORTHEAST TO NEAR CKB. NEAR AND AHEAD OF IT A FEW SHOWERS AND
EVEN ONE THUNDERSTORM HAD REDEVELOPED EARLY THIS MORNING. THE
ENHANCEMENT LIKELY DUE TO A VORT MAX...EVIDENT IN WV
IMAGERY...MOVING QUICKLY ACROSS NORTH CENTRAL OHIO.
ALL IN ALL EXPECT A NICE DAY FOR MOST FOLKS AS THE AFOREMENTIONED
FRONT MOVES THROUGH THE AREA...UNDER PARTLY TO MOSTLY SUNNY SKIES
BY THE AFTERNOON AND SEASONABLY WARM TEMPS. LARGE SCALE FORCING FOR
SUBSIDENCE WILL OVERSPREAD THE FORECAST AREA FROM NW TO SE AS A
500MB S/W TROUGH PUSHES EASTWARD ACROSS AND EXITS TO THE EAST AROUND
THE 18Z-21Z TIME FRAME. BY THE AFTERNOON HOURS HOWEVER...THE SFC
FRONT BEGINS TO WASH OUT AND AS SFC HIGH PRESSURE REBUILDS TO THE
EAST. MODELS IN GOOD AGREEMENT WITH GOOD SFC CONVERGENCE ALONG THE
EASTERN HIGH TERRAIN PEAKS AS SFC FLOW ON THE EAST SIDE RETURNS
QUICKLY TO THE EAST/SOUTHEAST...WHILE FLOW ON THE WINDWARD SIDE
REMAINS NORTH/NORTHWEST. SOME QUESTION AND DOUBT AS TO THE DEPTH OF
MOISTURE BEING DEPICTED ON LATEST NAM12 SOUNDINGS HOWEVER...AND
LATEST RUC13 SOUNDINGS ARE INDEED MUCH DRYER IN LOWER LEVELS. EVEN
WITH THE MORE SATURATED NAM12...PWATS STILL ONLY PROGGED AROUND
0.8IN-0.9IN WITH VERY DRY AIR ALOFT WHICH WOULD SERVE TO LIMIT
COVERAGE. PREV FCST HAD A GOOD HANDLE ON THIS AND WILL CONTINUE
SLIGHT CHANCE TO LOW CHANCE POPS ESSENTIALLY FROM THE HIGHEST PEAKS
AND POINTS SOUTH AND EAST...WITH STORM MOTION TO THE SOUTHEAST. DID
INSERT A SLIGHT THUNDER MENTION WITH DECENT INSTABILITY IN THAT
AREA. AS SUCH...KEPT CLOUD COVER HIGHER IN THE EASTERN HIGH COUNTRY
AS WELL. ALSO NUDGED MAX TEMPS UP AN ADDITIONAL DEGREE OR TWO FOR
MOST LOCATIONS PER LATEST PROGGED 925MB AND 850MB TEMPS WITH MOS
GUIDANCE SUPPORTING...ALTHOUGH DID KEEP MAX TEMPS IN THE MOUNTAINS
JUST A BIT LOWER WITH MORE CLOUDS AND SOME AFTERNOON PRECIP
POTENTIAL.
OVERNIGHT FORECAST REMAINS VIRTUALLY UNCHANGED FROM PREV SHIFT
THINKING...WITH MINS IN THE MID AND UPPER 50S LOWLANDS. WILL HAVE
PRECIP ENDING AT 00Z THU IN THE MOUNTAINS. AREAS OF FOG ARE A GOOD
BET ONCE AGAIN IN THE LOWLANDS UNDER A MOSTLY CLEAR SKY AND
NEAR-CALM WINDS...ALTHOUGH SOME LOWER DEWPOINTS ACROSS SE OHIO AND
MORE CLOUD COVER IN THE MOUNTAINS MAY LIMIT COVERAGE IN THOSE
AREAS.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
SFC HIGH PRESSURE MOVE OFF SHORE THE NORTHEAST COAST LATE
THURSDAY LOSING ITS INFLUENCE WEST OF THE APPALACHIANS.
HOWEVER...ABUNDANT LOW LEVEL MOISTURE AND ELEVATED HEAT SOURCES
COULD PRODUCE ISOLATED AFTERNOON SHOWERS OR STORMS OVER HIGHER
ELEVATIONS THROUGH THE WEEKEND.
A MID LEVEL RIDGE MOVES OVERHEAD SATURDAY PROVIDING SOME
SUBSIDENCE AND CLEAR SKIES. AFTERNOON CU WILL BE COMMON JUST TO
DISSIPATE AFTER SUNSET.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
SURFACE HIGH PRESSURE WILL REMAIN CENTERED ACROSS THE SOUTHEAST
STATES...WITH A RIDGE EXTENDING NORTH INTO WEST VIRGINIA.
SOUTHERLY WINDS WILL RESULT IN DEW POINTS INCREASING TO THE UPPER
60S AND LOWER 70S. AS A RESULT...ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORM WILL BE A POSSIBILITY...MAINLY DURING THE AFTERNOON AND
EVENING HOURS.
AN UPPER LEVEL TROF AND AN ASSOCIATED COLD FRONT WILL APPROACH FROM
THE WEST LATE IN THE PERIOD...RESULTING IN BETTER CHANCES FOR
SHOWERS AND STORMS. THE BEST CHANCE OF GETTING WET WILL CONTINUE TO
BE DURING THE AFTERNOON AND EVENING HOURS.
EXPECT DAYTIME TEMPERATURES TO GENERALLY BE 5 OR MORE DEGREES
ABOVE NORMAL DURING THE PERIOD.
&&
.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
16Z WEDNESDAY THROUGH 12Z THURSDAY...
STRATUS ERODING QUICKLY SO THAT GENERAL VFR SCT-BKN CU WILL PREVAIL
AFTER 18Z. JUST A FEW SHOWERS AND PERHAPS A THUNDERSTORM ARE
POSSIBLE OVER THE EASTERN HIGH TERRAIN.
WILL ADD LOCALLY DENSE RIVER AND VALLEY FOG AFTER 06Z
TONIGHT...AFFECTING MOST MAJOR TERMINALS.
CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z WEDNESDAY...
FORECAST CONFIDENCE...MEDIUM.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z THURSDAY...
FORECAST CONFIDENCE: TIMING OF DENSITY OF REDUCED VIS AND/OR LOW
STRATUS AFTER 06Z THU 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.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EDT 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21
CRW CONSISTENCY H M H H H H H H H H H H
HTS CONSISTENCY M H H H H H H H H H H H
BKW CONSISTENCY M M M H H H H H H H H H
EKN CONSISTENCY H M M H H H H H H H H H
PKB CONSISTENCY M H H H H H H H H H H H
CKB CONSISTENCY H M H H H H H H H H H H
AFTER 18Z THURSDAY...
IFR OR WORSE FG DEVELOPING WED NT.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/50
NEAR TERM...JMV
SHORT TERM...ARJ
LONG TERM...JSH
AVIATION...JMV