826 
FXUS61 KRLX 082009
AFDRLX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
309 PM EST THU MAR 8 2012

.SYNOPSIS...
COLD FRONT CROSSES THIS EVENING.  COOLER FRIDAY AND SATURDAY AS HIGH 
PRESSURE BUILDS OUR WAY.  MILDER SUNDAY AS THE HIGH DRIFTS 
SOUTHEAST.  A MILD AND SHOWERY PATTERN RETURNS MONDAY AND TUESDAY.

&&

.NEAR TERM /THROUGH FRIDAY/...
TONIGHT...BEST LARGE SCALE FORCING FOR ASCENT MOVES ACROSS THE 
FORECAST AREA ROUGHLY BETWEEN 00Z-06Z AS REGION COMES UNDER 
INFLUENCE OF RIGHT ENTRANCE REGION OF STRENGTHENING 160KT 300MB JET 
STREAK TO THE NORTH. AT THE SURFACE...GENERAL CONSENSUS OF MODEL 
DATA DEPICTING THE COLD FRONT NEAR THE OHIO RIVER AROUND 00Z AND 
NEAR EASTERN CWA BORDER AROUND 03Z. PREVIOUS FCST STILL HAS GOOD 
HANDLE ON INITIAL TIMING OF POPS/QPF. HOWEVER...WITH RAPID DRYING IN 
LOWER/MID LEVELS BETWEEN 03Z-06Z WILL GO AHEAD AND END POPS FOR ALL 
LOCATIONS BY 06Z EXCEPT HIGHER TERRAIN WHERE WILL CONTINUE SLIGHT TO 
LOW CHANCE POPS THROUGH THE NIGHT. WILL DECREASE MINS BY A FEW 
DEGREES MAINLY ACROSS CENTRAL AND WESTERN ZONES WHERE SKIES WILL 
SCATTER EARLIER.

FRIDAY...UPPER LEVEL TROUGH AXIS CONTINUES ON TO THE EAST WITH 
NORTHWEST FLOW ALOFT AND RISING HEIGHTS. SKIES WILL BECOME MOSTLY 
SUNNY...WITH THE EXCEPTION OF THE FAVORED UPSLOPE LOCATIONS OF 
COURSE WHERE ENOUGH LOW LEVEL MOISTURE WILL BE TRAPPED ON NORTHWEST 
SFC WINDS TO CONTINUE WITH PARTLY CLOUDY SKIES HERE. ALSO HAVE 
LOWERED MAXES A FEW DEGREES FROM PREVIOUS FCST WITH MODEL CONSENSUS 
DEPICTING H925 TEMPS OF ABOUT 1.5C AT 18Z WITH WEAK COLD ADVECTION 
CONTINUING DURING THE AFTERNOON.    

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
UPSLOPE COLD ADVECTION FLOW BEHIND REINFORCING COLD FRONT THAT SLIPS 
THROUGH THE AREA FRI AFTERNOON COULD BE JUST ENOUGH FOR SNOW 
FLURRIES BENEATH THE INVERSION IN THE NORTHERN WV MOUNTAINS FRI 
EVENING.  ALSO INCREASED WINDS AND GUSTS THERE WITH THIS FLOW.  ALSO 
NOT SURE HOW QUICKLY WINDS WILL DECOUPLE ACROSS THE AREA IN GENERAL 
AS HIGH PRESSURE TAKES UNTIL THE DAYLIGHT MORNING HOURS OF SAT TO 
BUILD IN.

WEAK MID LEVEL WARM ADVECTION BRINGS ABOUT PATCHY MID AND HIGH CLOUD 
SAT AS SFC HIGH MOVES ACROSS.

MODELS CONTINUE SLOWER TREND WITH SOUTHERN STREAM CLOSED OFF UPPER 
LEVEL LOW COMING NE OUT OF ITS TRANSIENT REX BLOCK AND INTO THE 
CENTRAL PLAINS OVER THE WEEKEND.  THIS KEEPS DRY WEATHER GOING 
THROUGH SUN...WITH NOTHING MORE THAN AFTERNOON CU IN THE MOUNTAINS 
SUN WITH INCREASING MOISTURE IN LIGHT S FLOW.

BLENDED IN ADJMET FOR LOWS FRI NT...NOT TAKING THAT LOW GUIDANCE 
HOOK LINE AND SINKER ON ACCOUNT OF DOUBT AS TO TIMING OF 
DECOUPLING.  ALSO BLENDED IN ADJMET FOR HIGHS SAT TO REFLECT COOL 
AIR BENEATH SUBSIDENCE INVERSION...AND LOWS SAT NT WITH BETTER 
RADIATIVE COOLING.  STILL HAVE FRI NT THE COLDER OF THE TWO BUT 
WOULD NOT BE SURPRISED TO SEE LOWS EVEN CLOSER ULTIMATELY.  BLENDED 
IN ADJMET ON DEW PINTS AS WELL TO LOWER IN MOUNTAINS SAT AND 
INCREASE MORE SLOWLY SUN.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
CONTINUED OUR TREND TOWARD A SLOWER RETURN TO THE MOISTURE.  SO
HAVE DRY CONDITIONS HOLDING WELL THROUGH SUNDAY NIGHT...AND ALL 
NIGHT IN OUR EASTERN COUNTIES.  SO ROUNDING OUT A DRY MARCH 
WEEKEND.  

MID LEVEL HEIGHTS ABOVE NORMAL OVER THE SOUTHEASTERN STATES.  SO 
HAVE INITIAL FRONT WEAKENING IN THE OHIO VALLEY MONDAY AFTERNOON AND 
MONDAY NIGHT...AND NOT MOVING THROUGH.  SO NO SIGNS OF ANY COLD AIR 
INTRUSION NEXT WEEK. THIS ALSO MEANT INCREASING DEW POINTS AND 
MILDER NIGHTS INTO MID WEEK.  HOWEVER...SAME PATTERN CAUSES PROBLEMS 
WHEN...OR IF...TO REMOVE CHANCE POPS.   

ACCEPTED MOST HPC MEDIUM RANGE GUIDANCE FOR MONDAY INTO THURSDAY.  
MINIMUM TEMPERATURES INCREASE TO AROUND 50 DEGREES IN THE LOWLANDS 
DURING THIS PERIOD.  AS USUAL FOR MARCH...MAXIMUM TEMPERATURES WILL 
BE HIGHLY DEPENDENT ON TIMING OF SHOWERS...BUT MID 60S TO LOWER 70S 
APPEAR WIDESPREAD.

&&

.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
18Z THURSDAY THROUGH 18Z FRIDAY

BREEZY SOUTH/SOUTHWEST WINDS WILL CONTINUE THIS AFTERNOON AHEAD OF
THE COLD FRONT. SHOWERS CURRENTLY LOCATED ALONG AND WEST OF THE
OHIO RIVER WILL CONTINUE TO OVERSPREAD THE AREA THIS AFTERNOON.
GENERAL MVFR CONDITIONS CAN BE EXPECTED WITH THESE SHOWERS WITH
2-3SM WITH 1K-2K CIGS. COLD FRONT SHOULD BE NEAR OHIO RIVER SITES
AROUND 00Z AND NEAR OR THROUGH EASTERN SITES NEAR 03Z. A BRIEF
PERIOD OF IFR CIGS IS EXPECTED NEAR AND BEHIND THE FRONT FOR A 2-3
HOUR PERIOD. WINDS SHIFT TO THE NORTHWEST WITH THE FRONT...WITH
RAPIDLY IMPROVING CONDITIONS EXPECTED AT ALL BUT MOUNTAIN
LOCATIONS BY 06Z...WITH ALL LOCATIONS AT VFR BY 12Z.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z FRIDAY...
     
FORECAST CONFIDENCE...HIGH. 
     
ALTERNATE SCENARIOS: TIMING OF COLD FRONT AND ITS ASSOCIATED WIND 
SHIFT/IFR CEILINGS AND PRECIPITATION MAY DIFFER BASED ON SYSTEM
PROGRESSION.

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
EST 1HRLY       13   14   15   16   17   18   19   20   21   22   23   00
CRW CONSISTENCY  H    H    M    M    M    H    M    L    L    L    L    H
HTS CONSISTENCY  H    M    M    H    H    L    L    L    L    L    H    H
BKW CONSISTENCY  H    H    H    L    M    M    L    M    M    M    M    M
EKN CONSISTENCY  H    H    M    M    H    L    M    L    L    L    L    L
PKB CONSISTENCY  M    H    L    H    M    M    M    M    M    H    H    H
CKB CONSISTENCY  H    M    M    L    L    L    L    L    L    L    L    M

AFTER 18Z FRIDAY...
NO IFR CONDITIONS EXPECTED.

&&

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

&&

$$
SYNOPSIS...KTB/TRM/50
NEAR TERM...50
SHORT TERM...TRM
LONG TERM...KTB
AVIATION...50