FXUS61 KRLX 051039
AFDRLX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
536 AM EST SUN FEB 5 2012

.SYNOPSIS...
HIGH PRESSURE BUILDS IN TODAY. COLD FRONT PASSES TUESDAY NIGHT
FOLLOWED BY A WEAK WAVE MIDWEEK. ANOTHER COLD FRONT CROSSES FRIDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
CONSIDERABLE DIFFERENCES BETWEEN THE NAM AND GFS WITH THE HANDLING
OF THE LOW LEVEL MOISTURE TODAY. RUC SUPPORTS THE FASTER CLEARING
FOUND IN THE GFS. THEREFORE WILL LEAN MORE TOWARD THE FASTER
SOLUTION. WITH CALM WINDS TONIGHT AND DECENT RADIATION
CONDITIONS...WILL GO TOWARD THE LOWER END OF THE MOS GUIDANCE. WILL
ALSO INCLUDE VALLEY FOG.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
MDLS ARE STARTING TO CONVERGE ON HANDLING OF UPR LOW POISED TO MOVE
THRU ON MON. NAM/SREF CONT TO OPEN THIS UP INTO A WAVE ON
APPROACH...WITH REMAINDER OF GLOBAL MDLS KEEPING A STRONGER INTACT
CLOSED LOW AT H5. WILL FOLLOW HPC PREFERENCE FOR A ECWMF/GFS
BLEND...NOTING NAM TO BE AN OUTLIER ATTM. GIVEN THAT...WILL INCREASE
CLDS ACROSS S BY 18Z...WITH MOISTENING OF THE COLUMN THRU H7. WEAK
LIFT IN THIS LAYER AIDED BY UPR LOW SHOULD ALLOW LIGHT PRECIPITATION
TO BREAK OUT ACROSS SW VA...SOUTHERN COAL FIELDS AND SOUTHERN AND
CENTRAL WV MTNS BY AFTN. GLOBAL MDLS DO INDICATE QPF WITH
THIS...ALBEIT VERY LIGHT. THEREFORE...INTRODUCED CHC POPS ACROSS
AFOREMENTIONED AREAS...MAINLY FOR AFTN AND EARLY EVE. TEMP PROFILES
SUPPORT MAINLY LIQUID...PERHAPS ENDING AS A FEW WET FLAKES ACROSS
THE MTNS EARLY EVE. WILL SEE A SHARP LINE BETWEEN SUN AND CLDS.
THINK AREAS NORTH OF I64 CORRIDOR WILL SEE MAINLY SUNSHINE.

LOOKING AT QUIET WX FOR TUE UNDER SFC HIGH. A S/W TROF MAY BRING A
FEW SHRA/SHSN TO THE AREA WED. IF NOTHING ELSE...WILL INCREASE THE
CLDS.

GUIDANCE VERY SIMILAR TO INHERITED NUMBERS...SO LITTLE CHANGE
NECESSARY. HOWEVER...MAY SEE SOMEWHAT OF A TEMP GRADIENT MON WHERE
SE OH AND NORTHERN WV ENDS UP WARMER THAN SOUTHERN AREAS DUE TO CLDS.
OVERALL LOOKING AT AN ABV NORMAL PERIOD THRU MIDWEEK...NOTHING NEW
THIS WINTER.

&&

.LONG TERM /THURSDAY THROUGH SATURDAY/...
ZONAL FLOW TO START TRANSITIONS TO NW FLOW THIS PERIOD AS LONG WAVE
TROUGH AMPLIFIES IN THE E. THIS LONG WAVE WILL LIKELY BE TRANSIENT
AGAIN THOUGH PER ONGOING LACK OF HIGH LATITUDE BLOCKING...TO WHICH
THE LACK OF DEEP PENETRATION OF ARCTIC AIR DOWN INTO THE EASTERN
CONUS IS ALSO ATTRIBUTABLE.

PERIOD STARTS DRY TUE NT WITH HIGH PRESSURE GIVING WAY TO A MOISTURE
STARVED COLD FRONT WITH NO INFLOW FROM THE S. THAT FRONT PASSES
EARLY WED...FOLLOWED BY A WAVE AND UPPER LEVEL S/W TROF THAT CROSS
WED INTO WEDNESDAY NT. CARRIED CHANCE POPS FOR THIS IN KEEPING WITH
HPC...WHICH FOLLOWS THE ECMWF AND THEN THE ECENS MEAN WHICH BECOMES
A GOOD REPRESENTATION OF THE MODEL AVERAGE LATER IN THE PERIOD.

WEAK SFC HIGH PRESSURE FOR THU ALTHOUGH ANOTHER UPPER LEVEL S/W TROF
ALSO CROSSES.

A STRONGER COLD FRONT DROPS DOWN FRI AS THE EASTERN CONUS LONG WAVE
TROF BEGINS TO SET UP. CARRIED THE CHANCE FOR PRECIPITATION WITH
THIS STRONGER FRONT ALTHOUGH MOISTURE WILL AGAIN BE LIMITED...AGAIN
KEEPING CLOSE TO HPC GUIDANCE.

ADJUSTED TEMPERATURES TO OR TOWARD HPC EARLY ON WHICH ENTAILED
HIGHER VALUES WED AND LOWER VALUES THU AND THU NT. WENT LOWER THAN
HPC BEYOND THAT IN DEFERENCE TO THE MEX AND ISC. AGAIN THOUGH THERE
IS SOME QUESTION AS TO HOW MUCH COLDER IT GETS ONCE THE SECOND FRONT
ROLLS THROUGH.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
A LOW PRESSURE SYSTEM MOVING SOUTH OF THE REGION WAS CREATING
IFR/LIFR CONDITIONS. SOME DRIER AIR WILL SLOWLY PUSH SOUTHEASTWARD
ACROSS THE REGION DURING THE DAY...ALLOWING FOR CONDITIONS TO
GRADUALLY CHANGE TO VFR FROM NORTHWEST TO SOUTHEAST TODAY. VFR
CONDITIONS CAN THEN BE EXPECTED THIS EVENING. VALLEY FOG IS EXPECTED
TO FORM LATE SUNDAY NIGHT.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z MONDAY...

FORECAST CONFIDENCE: MEDIUM.

ALTERNATE SCENARIOS: TIMING OF CEILINGS AND VISIBILITIES IMPROVING
COULD 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 11 12 13 14 15 16 17 18 19 20 21 22
EST 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
CRW CONSISTENCY M M M M M L M M H H H H
HTS CONSISTENCY H H M H M M M H H H H H
BKW CONSISTENCY L L L M M H L L H M H H
EKN CONSISTENCY L L L M L H M H H H H H
PKB CONSISTENCY M M M M H H H H H H H H
CKB CONSISTENCY L L H M L L M H H H H H

AFTER 12Z MONDAY...
IFR/LIFR POSSIBLE IN VALLEY FOG MONDAY MORNING...ESPECIALLY IN
MOUNTAIN VALLEYS.

&&

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

&&

$$
SYNOPSIS...TRM/RPY/30
NEAR TERM...RPY
SHORT TERM...30
LONG TERM...TRM
AVIATION...RPY








Back to Main Forecast Discussion Page