-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRLX 082009
AFDRLX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
256 PM EST SAT MAR 8 2014

.SYNOPSIS...
-- Changed Discussion --
WEAK COLD FRONT TONIGHT WITH SOME ACCOMPANYING LIGHT SHOWERS. MILD
MONDAY AND TUESDAY. STORM SYSTEM MIDWEEK FOLLOWED BY COLD HIGH
PRESSURE TO END THE WORK WEEK.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH SUNDAY/...
OVERALL FORECAST THINKING HAS NOT CHANGED MUCH IN THE GENERAL SENSE
FROM PREV SHIFT...WITH LATEST 12Z MODEL RUNS. COLD FRONT WILL PUSH
ACROSS FROM NORTHWEST TO SOUTHEAST OVERNIGHT...BRINGING WITH IT A
CHANCE OF LIGHT SHOWERS WITH IT. HAVE THE FRONT ENTERING THE FAR NW
ZONES BY 00Z THIS EVENING...NEAR THE INTERSTATE 79 CORRIDOR TO
COALFIELDS BY 06Z...AND THROUGH THE AREA QUICKLY BY 12Z SUN. OVERALL
LIFT CONTINUES TO REMAIN MARGINAL WITH THE BEST LIFT BYPASSING THE
AREA TO THE NORTH. MOST OF THE LIFT AND MOISTURE ALONG AND JUST
BEHIND THE COLD FRONT ITSELF AND IN THE END...THE FRONTAL PASSAGE
MAY ONLY PRODUCE A SCT-BKN FAIRLY NARROW BAND OF LIGHT SHOWERS AS IT
MOVES THROUGH. STILL ONLY EXPECTING A FEW HUNDREDTHS OF PRECIP FOR
ANY ONE LOCATION. IT/S POSSIBLE THAT SOME LOCATIONS ACROSS THE FAR
NORTHERN ZONES AND HIGHEST ELEVATIONS MAY SEE A FEW SNOWFLAKES
AND/OR VERY LIGHT FREEZING MIST/DRIZZLE AS TEMPS COOL TOWARDS THE
FREEZING MARK WHILE THE COLUMN DRIES QUICKLY AT -10C...BUT NO SNOW
IS EXPECTED TO ACCUMULATE NOR IS ANY FREEZING MIST/DRIZZLE EXPECTED
TO PRESENT A HAZARD.

SHORTWAVE AND FRONT CONTINUE QUICKLY EASTWARD AFTER 12Z
SUNDAY...WITH NORTHWEST FLOW ALOFT AND SFC HIGH PRESSURE NOSING IN
FROM THE WEST. EXPECT ALL PRECIP TO HAVE ALREADY ENDED FOR THE
FORECAST AREA...BUT WILL LINGER A SLIGHT CHANCE OF PRECIP ACROSS THE
FAR SOUTHERN ZONES AT 12Z. LOCATIONS NEAR AND WEST OF THE OHIO RIVER
WILL ALREADY BE MOSTLY CLEAR TO PARTLY CLOUDY. EARLY MORNING CLOUDS
FURTHER EAST AND ACROSS THE EASTERN MOUNTAINS WILL RAPIDLY SCATTER
OUT BY LATE MORNING...RESULTING IN A MOSTLY SUNNY DAY FOR ALL BY THE
AFTERNOON HOURS. VERY FEW CHANGES MADE TO INHERITED MAX TEMPS
SUNDAY. STILL EXPECTING GENERAL MID/UPPER 40S FOR THE
LOWLANDS...WITH LOW 40S SE OHIO AND INTO THE LOWER 50S FOR THE FAR
SOUTHERN ZONES. DID CODE UP A SOMEWHAT NON-DIURNAL TEMP CURVE FOR
THE HIGH PEAKS WITH COLD ADVECTION CONTINUING THERE INTO THE LATE
MORNING AND EARLY AFTERNOON HOURS...BEFORE A MODEST TEMP RECOVERY IN
THE MID/LATE AFTERNOON.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
-- Changed Discussion --
MODELS SHOWING A FRONTAL BOUNDARY SLIDING INTO THE REGION ON
MONDAY...STALLING...THEN PUSHING BACK NORTHWARD ON TUESDAY. ALTHOUGH
SOME DIFFERENCES EXIST IN THE TIMING AND PLACEMENT OF THIS
BOUNDARY...THE MODELS DO AGREE THAT LIMITED MOISTURE WILL PREVENT
ANY PRECIPITATION. WILL CONTINUE WITH A DRY FORECAST FOR THESE
PERIODS.
-- End Changed Discussion --

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
-- Changed Discussion --
THE 12Z GFS AND ECMWF RUNS LOOK IN AGREEMENT WITH A SHORTWAVE
EMERGING FROM THE SOUTHERN PLAINS IN THE SOUTHERN STREAM EVIDENT IN
H5 HEIGHTS AND VORTICITY MAX...BRINGING GOOD CHANCE OF PCPN
WEDNESDAY. THIS FEATURE WILL PROBABLY BRING A WEAK COLD FRONT
EXPECTED TO OSCILLATE NORTH AND SOUTH OVER OUR CWA ON WEDNESDAY.
RIGHT AFTER...THE ECMWF SLOWED DOWN A BIT A STRONGER UPPER LEVEL
TROUGH EXPECTED TO SWING SOUTHEAST EARLY WEDNESDAY NIGHT PROVIDING
EXTRA FORCING ALONG THE OLD FRONT. THIS SETUP CALLS FOR A SURFACE
LOW DEVELOPING ALONG THE FRONT AND PASSING ACROSS THE SOUTHERN
PORTIONS OF THE AREA. IT STILL UNCERTAIN HOW STRONG THE SFC LOW WILL
DEVELOP. HOWEVER...THIS LATER TROUGH...ALONG WITH H85 TEMPERATURES
EXPECTED TO BE ABOVE FREEZING...COULD PROVIDE ENOUGH LIFT TO PRODUCE
WIDESPREAD HALF AN INCH OF RAIN ACROSS THE AREA...AS SUGGESTED BY
BOTH MODELS.

THE SECOND UPPER TROUGH WILL BRING MUCH COLDER AIR BEHIND...CAPABLE
TO PUSH THE COLD FRONT EAST OF THE APPALACHIAN BY THURSDAY MORNING.
MEANWHILE...DEEP NORTHWEST FLOW WILL ALLOW FOR UPSLOPE SNOW ON OUR
NORTHEAST COUNTIES UNDER SHALLOW MOISTURE LAYER THROUGH EARLY
THURSDAY. SO...EXPECT BRIEF PERIOD OF MIXED PCPN BEFORE TURNING INTO
ALL SNOW MAINLY ACROSS THE NORTHERN THIRD OF THE AREA...WITH BETTER
CHANCES CONFINED TO THE MOUNTAINS DUE TO UPSLOPE EFFECTS.

ANY SNOW ACCUMULATIONS LOOK MINOR AT THIS TIME...EVEN IN THE
MOUNTAINS.  DRY AND COLD HIGH PRESSURE BUILDS IN FROM THE WEST
THURSDAY AND DOMINATE INTO LATE FRIDAY.
-- End Changed Discussion --

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
VFR WITH CEILINGS LOWERING AHEAD OF A WEAK COLD FRONT ARRIVING
LATE THIS EVENING AND TONIGHT...MOVING NORTHWEST TO SOUTHEAST
THROUGH THE AREA. WHILE NOT AN OVERLY SIGNIFICANT WEATHER
MAKER...THIS FRONT AND THE ASSOCIATED SHOWERS WILL BE BRINGING IN
MVFR CEILINGS THAT MAY DROP BELOW THE 2KFT THRESHOLD...WITH BRIEF
MVFR VISBYS IN THE SHOWERS THEMSELVES.

CKB...EKN...AND BKW CAN EXPECT WIND GUSTS TO 20KTS OUT OF THE WEST
TODAY DURING BEST MIXING HOURS. WINDS WILL SHIFT OUT OF THE
NORTHWEST AS THE COLD FRONT MOVES THROUGH TONIGHT...WITH BRIEF
GUSTS FOR AN HOUR OR TWO BEHIND THE FRONT AROUND 15-20KTS.

FLIGHT CONDITIONS WILL RAPIDLY IMPROVE TO VFR BTWN 12Z-15Z FOR
MOST LOCATIONS WITH LOW CEILINGS SCATTERING OUT...WITH CIGS
POSSIBLY TAKING JUST A LITTLE LONGER TO BREAK UP OVER THE EASTERN
HIGH TERRAIN AS USUAL.

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

FORECAST CONFIDENCE: MEDIUM TO HIGH.

ALTERNATE SCENARIOS: TIMING OF SHOWERS MAY VARY. BRIEF IFR IN A
HEAVIER SHOWER IS POSSIBLE.

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       20   21   22   23   00   01   02   03   04   05   06   07
EST 1HRLY       15   16   17   18   19   20   21   22   23   00   01   02
CRW CONSISTENCY  H    H    H    H    M    M    M    M    M    H    M    M
HTS CONSISTENCY  H    H    M    M    M    M    M    M    H    H    H    H
BKW CONSISTENCY  H    H    H    H    M    M    M    M    M    H    M    L
EKN CONSISTENCY  M    M    M    M    M    M    M    M    M    L    L    L
PKB CONSISTENCY  M    H    M    M    M    M    M    H    H    H    H    H
CKB CONSISTENCY  M    M    M    M    M    M    M    M    H    M    L    L

AFTER 18Z SUNDAY...
IFR POSSIBLE IN A STRONG LOW PRESSURE SYSTEM WEDNESDAY.

&&

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

&&

$$
SYNOPSIS...ARJ/RPY/50
NEAR TERM...50
SHORT TERM...RPY
LONG TERM...ARJ
AVIATION...50