-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRLX 240531
AFDRLX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
131 AM EDT FRI MAY 24 2013

.SYNOPSIS...
SECOND COLD FRONT CROSSES OVERNIGHT. UPPER DISTURBANCE CROSSES
EARLY SATURDAY AND SUNDAY NIGHT. COOL CANADIAN HIGH PRESSURE
ARRIVES TO START THE WEEKEND.

&&

.NEAR TERM /THROUGH TODAY/...
-- Changed Discussion --
130 AM UPDATE...NO SIGNIFICANT CHANGES.

PREVIOUS DISCUSSION...
SHRA/TSRA ALONG A LLVL CONVERGENCE BOUNDARY IN C WV...WHICH WILL
SHIFT E NEXT SEVERAL HRS. HAVE LKLY POPS WITH THIS AS IT WORKS
INTO REMAINDER OF CWA LATER THIS AFTN. MAY SEE SOME MTN SHRA FORM
AHEAD OF THIS ON DIFFERENTIAL HEATING. SHOULD SEE SOME DEEPER
CONVECTION FORM SHORTLY WITH SOME SFC HEATING. LATEST SPC MESO
DISCUSSION HAS PLACED MUCH OF WV ZONES IN POTENTIAL FOR WATCH. NOT
SURE HOW STRONG CONVECTION WILL BE WITH LESS SFC INSTABILITY THAN
PAST FEW DAYS. HOWEVER...FRZ LVLS ARE LWR AND BETTER UPR SUPPORT
WITH APPROACH OF UPR TROF. DEEPER SHEAR A LITTLE BETTER THAN
YESTERDAY AS WELL. DAMAGING WIND PROGS NOT AS IMPRESSIVE AS PAST
FEW DAYS WITH MDLS SHOWING MARGINAL DOWNDRAFT SIGNAL AS SFC TO H7
DELTA THETA E NOT AT GREAT. OF PERHAPS MORE CONCERN IS WATER.
CONCERNED S PART OF THIS BOUNDARY MAY TRY TO TRAIN SOMEWHAT WITH
THE BETTER PUSH ACROSS SE OH/N LOWLANDS INITIALLY. ALREADY SEEING
THIS HAPPENING NEAR TRI STATE. 1 HR FFG HAS COME DOWN CONSIDERABLY
WITH MUCH OF WV ZONES 1 TO 1.25 INCHES AND N LOWLANDS LESS GETTING
DOWN TO .75. ISSUED FLASH FLOOD WATCH EARLIER FOR MUCH OF THE
LOWLANDS AND N MTNS. WILL END IT AT 00Z WITH PWS COMING DOWN TO 1
INCH.

MAY SEE A FEW BANDS OF SCT SHRA/TSRA BEHIND THIS UNTIL UPR TROF AXIS
AND COLD FRONT CROSSES THIS EVE. SHOULD SEE SOME POST FRONTAL
SHRA CONT ALONG AND E OF I79 OVERNIGHT WITH LOW STRATUS DEVELOPING
ELSEWHERE.

CAA COMMENCES IN EARNEST LATE WITH H85 TMPS BOTTOMING OUT CLOSE TO
0Z. NOT OUT OF THE QUESTION FOR SNOWSHOE TO SEE SOME WET
SNOWFLAKES ARND DAWN. AS TROF AXIS PULLS E COLUMN COLUMN DRIES OUT
CONSIDERABLY AND WILL ALLOW MORNING STRATUS TO MIX OUT IN MORNING
WITH JUST SOME FLAT CU IN AFTN HEATING. WENT CLOSER TO MET FOR
HIGHS WITH LWR 60S AND SOME 40S IN HIGHEST ELEVATIONS...DEFINITELY
NOT INDICATIVE OF LATE MAY.
-- End Changed Discussion --

&&

.SHORT TERM /TONIGHT THROUGH SUNDAY/...
HIGH PRESSURE BUILDS ACROSS THE GREAT LAKES FRIDAY NIGHT TO
PROVIDE DRY AND COLDER AIR UNDER NORTHERLY FLOW. DRY WEATHER
CONTINUES THROUGH THE WEEKEND AS CALM FLOW UNDER HIGH PRESSURE
SYSTEM EXTENDS INTO OH VALLEYS AND WV.

CLEAR SKIES...CALM FLOW AND SOME COLD ADVECTION AT H850 WILL BRING
TEMPERATURES AT OR BELOW FREEZING POSING A WIDESPREAD THREAT FOR
GROWING VEGETATION TO FROST OR FREEZE INTO EARLY SATURDAY MORNING.

KEPT POTENTIAL FOR FROST/FREEZE IN THE HWO.

HIGH PRESSURE MOVES ACROSS THE AREA INTO TUESDAY TO PROVIDE MOSTLY
DRY WEATHER. SOME CLOUDS WILL BE COMMON...AND A SHORTWAVE AT H5 BRINGS
VORT MAXES SATURDAY NIGHT.

WENT CLOSER TO SIMILAR MET/MAV NUMBERS FOR TEMPERATURES THROUGH
THE PERIOD.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE REMAINS IN CONTROL TO AT LEAST EARLY WEDNESDAY
PROVIDING DRY WEATHER WITH A SLOW WARMING TREND.

ANOTHER MID LEVEL SHORTWAVE WILL MOVE THROUGH SUNDAY NIGHT FOR LOW
CHANCE FOR RAIN SHOWERS INTO MONDAY.

A WARM FRONT DEVELOPS AS IT APPROACHES THE REGION ON MONDAY. AS A
RESULT...THERE WILL BE A CHANCE OF SHOWERS AND STORMS MONDAY AND
TUESDAY...MAINLY DURING THE AFTERNOON AND EVENING HOURS.

FOR SATURDAY...TEMPERATURES SHOULD BE NEAR NORMAL WITH DAYTIME
HIGHS IN THE 70S ACROSS LOWLANDS...WITH 60S ACROSS THE HIGHER
ELEVATIONS. TEMPERATURES WILL CONTINUE TO CLIMB IN THE UPPER TO
MID 80S BY THE END OF THE WEEK. LOWS WILL RANGING IN THE 60S.

&&

.AVIATION /05Z FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --
MVFR DECK IN PLACE ACROSS CWA TO START THE TAF PERIOD. ALSO SOME
SHOWERS DRIFTING EASTWARD ACROSS THE REGION AS A COLD FRONT PUSHES
THROUGH. THE COLD FRONT ALSO BRINGING GUSTY N/NW WINDS...WHICH
SHOULD REMAIN THROUGH THE EARLY MORNING...DECREASING FOR A FEW
HOURS AROUND SUNRISE...THEN PICK BACK UP WITH MIXING DURING THE
DAY. THE BACK EDGE OF THE MVFR CLOUD DECK IS CURRENTLY IN CENTRAL
IN/MI...AND SHOULD CONTINUE PUSHING EAST OVER THROUGH THE EARLY
MORNING...WITH VFR TAKING OVER IN THE WEST AROUND SUNRISE...AND
LINGERING IN THE EAST A BIT LONGER. ALSO HAVE SOME POCKETS OF IFR
CEILINGS...SO INCLUDED THAT AT NORTHERN AND MOUNTAINS SITES. WITH
THE WINDS REMAINING...FOG NOT A HUGE CONCERN THIS MORNING..BUT DID
INCLUDE IN SOME MVFR FOG IN MOUNTAIN VALLEYS. ONCE THE CURRENT
CLOUDS CLEAR...VFR SHOULD REMAIN THROUGH THE REST OF THE TAF
PERIOD...WITH WINDS DECREASING AS THE SUN SETS TONIGHT.

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

FORECAST CONFIDENCE...MEDIUM.

ALTERNATE SCENARIOS: TIMING OF DISSIPATION OF MVFR/IFR CEILINGS
THIS MORNING MAY VARY A COUPLE OF HOURS.

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                              FRI 05/24/13
UTC 1HRLY       06   07   08   09   10   11   12   13   14   15   16   17
EDT 1HRLY       02   03   04   05   06   07   08   09   10   11   12   13
CRW CONSISTENCY  M    M    M    M    M    H    H    H    H    H    H    H
HTS CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
BKW CONSISTENCY  L    L    L    M    M    M    M    M    M    M    M    H
EKN CONSISTENCY  L    L    M    M    M    M    M    M    L    L    M    H
PKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
CKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H

AFTER 06Z SATURDAY...
IFR CONDITIONS POSSIBLE IN FOG EARLY SATURDAY MORNING.
-- End Changed Discussion --

&&

.EQUIPMENT...
-- Changed Discussion --
RADAR WILL BE OUT OF SERVICE AT LEAST THROUGH THE WEEKEND WHILE
AWAITING PARTS.
-- End Changed Discussion --

&&

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

&&

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