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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRLX 250509
AFDRLX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
109 AM EDT SAT MAY 25 2013

.SYNOPSIS...
CHILLY HIGH PRESSURE TAKES CHARGE TONIGHT INTO SATURDAY. WARM
FRONT LIFT NORTH INTO THE OHIO VALLEY AND WEST VIRGINIA EARLY
TUESDAY. A WARMING TREND EXPECTED MEMORIAL DAY THROUGH NEXT WEEK.

&&

.NEAR TERM /THROUGH TODAY/...
9 PM UPDATE. STILL GOING WITH A FROST SCENARIO FOR THE LOW LANDS
UNDER A FROST ADVISORY. DEWPOINTS ACROSS THE NORTH ARE NOW IN THE
LOW TO MID 30S ON A DECREASING NORTH WIND. WHILE THE MAJOR CITIES
MAY ESCAPE FROST...THE OUTLYING AREAS AND FAVORED LOW SPOTS ARE
INCREASINGLY LIKELY FOR SOME FROST. WILL MAKE NO CHANGE TO HEADLINES
NOR CURRENT FORECAST.


PREVIOUS DISCUSSION...
VERY TOUGH FCST TONIGHT REGARDING FROST/FREEZE POTENTIAL. DWPTS
CURRENTLY STRADDLING THE MARGINAL THRESHOLD FOR FROST TONIGHT
GIVEN AFTN MIXING. NOT SURE IF THESE GO LWR NEXT FEW HRS BEFORE
RECOVERING THIS EVE. GUIDANCE FOR METRO AREAS IN THE LOWLANDS RUN
32 TO 40F FROM KHTS TO KCRW. H925 WINDS STAY UP ARND 20 KTS
OVERNIGHT AS SFC HIGH BUILDS IN TO ALLOW WINDS AT THE GROUND TO
TRY TO GO CALM. ALL OF THIS COMPLICATES MATTERS FOR EXPANDING
FROST ADV. HOWEVER...GIVEN TIME OF YEAR AND FACT THAT MOST FOLKS
HAVE SOME OF THEIR VEGGIES IN THE GROUND ALONG WITH ANNUAL PLANT
INVESTMENTS...FELT PRUDENT TO LEAN A LITTLE LIBERAL AND EXPAND TO
ENCOMPASS REST OF CWA SAVE FOR S COAL FIELDS TO SW VA. OUTLYING
AREAS WILL SEE BEST SHOT OF FROST. HEADLINE SHOULD GARNER MORE
ATTENTION FOR FOLKS TO TAKE PRECAUTIONS TO BE ON SAFE SIDE. ALSO
EXPANDED FRZ WARNING TO RALEIGH BASED ON GUIDANCE RANGING FROM 28F
TO 33F. THEY WILL HAVE GET UNDER INVERSION THOUGH GIVEN H925 WINDS
OFF MDLS OVERNIGHT. OTHER CONCERN IS STRATUS OVERNIGHT ACROSS THE
N. NAM HAS BEEN WAY TOO FAST IN ERADICATING THE LLVL MOISTURE VS
RUC WHICH HAS BEEN PRETTY STEADY. RUC SHOWS CLDS LIFTING AND SCT
THIS EVE ACROSS THE N BEFORE REDEVELOPING IN N MTNS BY 06Z. NAM
KEEPS ENTIRE COLUMN DRY BUT HAS NOT HANDLED TDY WELL AT ALL. SO
WILL LEAN TOWARD RUC AND REDEVELOP SOME STRATUS IN N MTNS LATE
TONIGHT. THIS MAY KEEP TEMPS UP TONIGHT ESPECIALLY IN
VALLEYS...BUT STILL FEEL AOB FRZ TEMPS WILL BE REALIZED.

UPR TROF AXIS SHIFTS TO E COAST ON SAT WITH SOME RECOVERY IN TEMPS
COMPARED TO TDY. INHERITED TEMPS LOOKED GOOD AND ONLY NEEDED
TWEAKING SOME...MAINLY ACROSS THE N.

&&

.SHORT TERM /TONIGHT THROUGH MONDAY/...
MADE MODIFICATIONS TO THE SHORT TERM FORECAST AS FOLLOWS:

HIGH PRESSURE WILL BE IN CONTROL THROUGH THE WEEKEND...KEEPING DRY
CONDITIONS AREAWIDE. MODELS SHOW A MID LEVEL SHORTWAVE...EVIDENT
IN H5 CHARTS...UNDER NORTHWEST FLOW ALOFT...MOVING ACROSS SOUTHERN
OH...SOUTHEAST INTO NORTHWEST KY. REMOVED ANY POPS FOR THE WEEKEND
AS MOISTURE LOOKS VERY LIMITED OVER WV. IN FACT...THERE COULD BE
SOME CLEARING SATURDAY NIGHT INTO SUNDAY MORNING...KEEPING
TEMPERATURES AT OR JUST BELOW FREEZING OVER POCAHONTAS AND
RANDOLPH COUNTIES. INCLUDED PATCHY FROST OVER NORTHEAST MOUNTAINS.

HIGH PRESSURE MOVES EAST OVER THE MID ATLANTIC STATES KEEPING
INFLUENCE OVER WV FOR A DRY SUNDAY THROUGH MONDAY NIGHT.

MINOR CHANGES TO TEMPERATURES THROUGH THE PERIOD...PERHAPS A
COUPLE DEGREES LOWER CLOSER TO THE COOLER MET.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
ANOTHER SHORTWAVE UNDER NORTHWEST FLOW ALOFT PASSES ACROSS
SOUTHEAST OH AND WV MONDAY AND TUESDAY. AT THE SAME TIME...A WARM
FRONT LIFTS NORTH INTO SOUTHERN OH...ACROSS WV AND VA ORIENTED
WEST TO EAST BY 12Z TUESDAY. THESE TWO FEATURES WILL BE CAPABLE TO
PRODUCE SHOWERS AND STORMS LATE MONDAY INTO TUESDAY AS THE WARM
FRONT MOVES NORTH OF THE AREA BY EARLY WEDNESDAY. INCREASED POPS
TO CHANCE INCLUDING THUNDER IN WEATHER GRIDS ACCORDINGLY.

HIGH PRESSURE TAKES CONTROL BY EARLY WEDNESDAY PROVIDING DRY
WEATHER WITH A SLOW WARMING TREND THROUGH THE REST OF THE WEEK.
TWEAKED COUPLE OF DEGREES DOWN FROM HPC GUIDANCE IN THE EXTENDED
PERIODS.

&&

.AVIATION /05Z SATURDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
VFR CONDITIONS EXPECTED ACROSS THE FORECAST AREA THROUGH THE TAF
PERIOD. ONE EXCEPTION IS SOME MVFR CEILINGS CURRENTLY IN
EKN...AND COULD ALSO GET SOME MVFR VISIBILITY THERE BEFORE THE SUN
COMES UP. EKN SHOULD RETURN TO VFR BY 13Z-14Z. VFR CU FIELD WILL
DEVELOP TODAY...GENERALLY 6-9KFT. UPPER LEVEL DISTURBANCE BRINGS
CLOUDS TO THE SOUTH TONIGHT...BUT AGAIN REMAINING VFR.

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

FORECAST CONFIDENCE...HIGH.

ALTERNATE SCENARIOS: TIMING AND DENSITY OF FOG AT EKN 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                                                  SAT 05/25/13
UTC 1HRLY       02   03   04   05   06   07   08   09   10   11   12   13
EDT 1HRLY       22   23   00   01   02   03   04   05   06   07   08   09
CRW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
HTS CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
BKW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
EKN CONSISTENCY  M    M    M    M    M    M    M    M    M    M    M    M
PKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
CKB CONSISTENCY  H    H    M    M    M    H    H    H    H    H    H    H

AFTER 06Z SUNDAY...
NO WIDESPREAD IFR EXPECTED.
-- End Changed Discussion --

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
WV...FROST ADVISORY UNTIL 8 AM EDT THIS MORNING FOR WVZ005>011-
     013>020-026>032-039-040.
     FREEZE WARNING UNTIL 8 AM EDT THIS MORNING FOR WVZ035>038-046-
     047.
OH...FROST ADVISORY UNTIL 8 AM EDT THIS MORNING FOR OHZ066-067-075-
     076-083>087.
KY...FROST ADVISORY UNTIL 8 AM EDT THIS MORNING FOR KYZ101>103-105.
VA...NONE.
-- End Changed Discussion --

&&

$$
SYNOPSIS...ARJ/30
NEAR TERM...JMV/30
SHORT TERM...ARJ
LONG TERM...ARJ
AVIATION...MZ