weather.gov     
National Weather Service

Area Forecast Discussion
NWS Homepage
This page is being discontinued on March 12, 2014.
The same data is available at this site. Please update your bookmarks.
Thank you, and we apologize for the inconvenience.
Please send an email to SR-SRH.Webmaster@noaa.gov with any concerns.


Current Version
Previous Version:    01  02  03  04  05  06  07  08  09  10  11  12  13  14  15  16  17  18  19  20  21  22  23  24  25  26  27  28  29  30  
   31  32  33  34  35  36  37  38  39  40  41  42  43  44  45  46  47  48  49  50  51  52  53  54  
[Printable]
334
FXUS61 KRLX 021034
AFDRLX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
617 AM EDT TUE SEP 2 2014

.SYNOPSIS...
FRONTAL SYSTEM TODAY WITH SHOWERS AND STORMS...SOME STRONG. VERY
WARM AND HUMID THROUGH THE END OF THE WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
6 AM UPDATE. TWEAKED POPS INTO LIKELY FOR FAR NORTHWEST ZONES THIS
MORNING...ALSO EXPANDED LOW POPS EARLY THIS MORNING INTO NORTH
CENTRAL WV...ALL PER RADAR TRENDS.

PREVIOUS DISCUSSION...
EVEN THOUGH WE ARE TRANSITIONING INTO THE COOL SEASON...THE PATTERN
STILL SHOWS SIGNS OF SUMMER AS STRONG UPPER RIDGING HOLDS ACROSS THE
SOUTHERN PART OF THE NATION. THIS KEEPS OUR AREA IN THE SOUTHERN
EDGE OF THE WESTERLIES WHICH HAS IMPLICATIONS ON ANY FRONT AFFECTING
US.

MODELS AGREE ON A STOUT UPPER TROUGH OVER THE MID MISSISSIPPI VALLEY
LIFTING NORTHEASTWARD ACROSS THE NORTHERN OHIO VALLEY TODAY AND ON
INTO NEW ENGLAND TONIGHT...WITH A VORT LOBE TRAILING SOUTH ACROSS
OUR AREA. HOWEVER...THE ASSOCIATED COOL FRONT IS WEAK AND WILL LOSE
DEFINITION AS IT TRIES TO DROP SOUTHEAST ACROSS THE AREA THIS
AFTERNOON AND EVENING. IT APPEARS THE FRONT ITSELF WILL HAVE LESSER
IMPACT ON OUR WEATHER. THE GREATEST IMPACT WILL COME FROM THE UPPER
TROUGH DYNAMICS IN THE FORM OF A WELL DEFINED RIGHT ENTRANCE REGION
OF THE UPPER JET AND THE TRAILING VORT LOBE. WITH PW`S AROUND 2
INCHES AND A MODEST 850 MB SOUTHWESTERLY JET COINCIDING WITH THE
UPPER DYNAMICS...WE EXPECT A BAND OF STRONG THUNDERSTORMS TO MOVE
ACROSS THIS AFTERNOON AND EVENING. SPC DOES HAVE THE NORTHWEST HALF
OF OUR AREA IN A SLIGHT RISK FOR SEVERE THUNDERSTORMS...SO WILL ADD
GUSTY WINDS AND SMALL HAIL FOR NOW TO THE WEATHER THIS AFTERNOON.
TIMING OF THE STORMS IS BASED ON GOOD MODEL AGREEMENT...REACHING THE
OHIO RIVER AROUND 18Z AND PROGRESSING TO THE MOUNTAINS BY 22Z.
THINGS QUICKLY WIND DOWN THIS EVENING AS THE UPPER TROUGH PULLS AWAY
AND LOSS OF HEATING...LEAVING ONLY THE FAR SOUTHEAST WITH A SLIGHT
CHANCE FOR SHOWERS BY MIDNIGHT. LEANING ON LOWER SIDE OF GUIDANCE
FOR MAX TEMPS NORTHWEST AND HIGHER SIDE SOUTHEAST DUE TO CLOUDS AND
CONVECTION.

FOR TONIGHT...SURFACE FRONT BY THIS TIME IS ILL DEFINED AT BEST AS
WEAK HIGH PRESSURE TAKES OVER. LOOKS LIKE ANY DRIER AIR THAT MAKES
IT INTO THE NORTH AND WEST WILL NOT GET ANY FARTHER. SO WITH LOSS OF
WIND FLOW AND DECREASING CLOUDS...EXPECT A GOOD DEAL OF RIVER AND
VALLEY FOG TONIGHT...EVEN UP NORTH AND WEST AS BETTER RADIATIONAL
COOLING WILL COMPENSATE FOR ANY LOSS OF MOISTURE. TEMPS TONIGHT WILL
BE A BLEND OF GUIDANCE.

&&

.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
STRONG UPPER LEVEL RIDGE OVER THE DEEP SOUTH PROVES TO BE PERSISTENT
AND STILL WILL NOT BE ABLE TO SHAKE THE 590DKM LINE THROUGH THE END
OF THE WEEK. DESPITE THE SURFACE HIGH PRESSURE BUILDING IN
WEDNESDAY...THINK WE WILL HAVE ENOUGH LOW LEVEL MOISTURE TO POP
ISOLATED SHOWERS/STORMS DURING THE DAYTIME HEATING HOURS. STRETCHED
THE SLIGHT CHANCE POPS THROUGH THE ENTIRE CWA BASED ON THIS
REASONING.

LEFT THURSDAY LARGELY DRY AS IN THE PREVIOUS FORECAST...WITH THE
MOUNTAINS AND TUG VALLEY IN THE SLIGHT CHANCE AREA AS BEFORE. NAM
BRINGS A WEAK TROUGH AXIS ALOFT OVER THE NORTHWESTERN ZONES IN
SOUTHEAST OHIO...BUT COLUMN WILL LIKELY BE TOO DRY AT THIS POINT FOR
ANYTHING OF SIGNIFICANCE TO DEVELOP.

BRING THE POPS BACK IN AS THE NEXT SYSTEM APPROACHES...AND FIGURE TO
GET SOME BETTER DESTABILIZATION DURING THE DAY WITH PRESSURE FALLS.

KEEP THE HIGH TEMPERATURES THROUGH THE PERIOD UNDER THE 90 DEGREE
MARK GIVEN THE TIME OF YEAR AND MOIST GROUND.

&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
HEATING BACK UP...AS THE SOUTHERN 500 MB RIDGE BUILDS BACK NORTH FOR
FRIDAY.  SOME AFTERNOON CONVECTION COULD OCCUR FRIDAY...BUT POPS
MOSTLY 20 AND 30 PERCENT.

PER WPC MEDIUM COORDINATION...CONTINUE TO TREND SLOWER THAN THE GFS
ON THE NEXT FRONT. 12Z GFS QUICKLY DRIES OUT OUR NORTHERN COUNTIES
SATURDAY EVENING INTO SUNDAY.  PREFER THE SLOWER ECWMF SOLUTION AT
THIS TIME...INCREASED POPS INTO LIKELY CATEGORY ON SATURDAY INTO
SATURDAY EVENING. HOLDING SOME CHANCE POPS EVEN INTO SUNDAY MORNING
FOR NORTHERN COUNTIES...AND INTO SUNDAY NIGHT FOR SOUTHERN
COUNTIES.  DRY MONDAY...EXCEPT AGAIN SOME SLIGHT CHANCE POPS ALONG
THE EASTERN SLOPES.

&&

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
12Z TUESDAY THRU 12Z WEDNESDAY...
A FRONTAL BOUNDARY WILL PUSH INTO THE AREA THIS AFTERNOON AND
LOSE DEFINITION AS IT TRIES TO CROSS THE AREA FROM WEST TO EAST
LATER THIS AFTERNOON AND EVENING. NEVERTHELESS...EXPECT A LINE OF
THUNDERSTORMS TO MOVE ACROSS...MAINLY THIS AFTERNOON AND EVENING.
OUTSIDE OF CONVECTION...VFR WILL PREVAIL TODAY. ALSO...SOUTHWEST
WINDS AHEAD OF THE FRONT WILL BECOME MODERATE THIS AFTERNOON WITH
GUSTS TO NEAR 20 MPH IN SOME LOCATIONS.

AFTER 00Z...FRONT CONTINUES TO LOSE DEFINITION AS WEAK HIGH
PRESSURE DEVELOPS OVER THE AREA. WITH CLOUDS AND WINDS
DECREASING...EXPECTING LIFR RIVER AND VALLEY FOG TO FORM BY
06Z...AFFECTING MOST OF THE MAJOR TERMINALS.

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

FORECAST CONFIDENCE: MEDIUM.

ALTERNATE SCENARIOS: TIMING OF SHOWERS AND THUNDERSTORMS COULD VARY
BY A COUPLE OF HOURS. ONSET OF FOG TONIGHT MAY BE DELAYED IF CLOUDS
HANG ON LONGER.

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
EDT 1HRLY       07   08   09   10   11   12   13   14   15   16   17   18
CRW CONSISTENCY  H    H    H    H    H    H    H    H    H    M    M    M
HTS CONSISTENCY  H    H    H    H    H    H    H    H    M    M    M    M
BKW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    M
EKN CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
PKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    M
CKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H

AFTER 12Z WEDNESDAY...
IFR IN RIVER AND VALLEY FOG EARLY WEDNESDAY MORNING.

&&

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

&&

$$
SYNOPSIS...JMV/26
NEAR TERM...JMV
SHORT TERM...26
LONG TERM...KTB
AVIATION...JMV











U.S. Dept. of Commerce
NOAA National Weather Service
1325 East West Highway
Silver Spring, MD 20910
E-mail: w-nws.webmaster@noaa.gov
Page last modified: May 16, 2007
NATIONAL WEATHER SERVICE: for Safety, for Work, for Fun - FOR LIFE