Area Forecast Discussion
Issued by NWS Charleston, WV

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 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
000
FXUS61 KRLX 012315
AFDRLX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
715 PM EDT TUE SEP 1 2015

.SYNOPSIS...
HIGH PRESSURE IN CONTROL THIS WEEK. DIURNAL HEATING COULD PRODUCE
ISOLATED SHOWERS OR STORMS THROUGH THE WEEK.  SOUTHEAST FLOW MAY
INCREASE FRIDAY NIGHT INTO SATURDAY.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
715 PM UPDATE...TWEAKED SKY GRIDS BASED ON CURRENT TRENDS.
OTHERWISE...NO CHANGES WERE NECESSARY.

PREVIOUS DISCUSSION FOLLOWS...
DIURNAL HEATING SHOWERS AND STORMS TO REMAIN CONCENTRATED IN
SOUTHERN OHIO AND IN THE HIGHER ELEVATIONS TO THE EAST. THESE WILL
BE SLOW MOVING...BUT GENERALLY SMALL IN TERMS OF SURFACE AREA AND
HAVE TRENDED TOWARDS A SOUTHWARD DRIFT.

UPPER LEVEL LOW CURRENTLY OVER INDIANA WILL DRIFT INTO THE CENTRAL
APPALACHIANS TONIGHT...WITH LITTLE MOISTURE TO WORK WITH. THIS
MAKES THE CLOUD COVER FORECAST TRICKY...AND SUBSEQUENT VALLEY FOG
FORMATION. AT THE SURFACE...HIGH PRESSURE REMAINS IN CONTROL.

WEAK DISTURBANCES ALOFT KEEP THE LOW CHANCES FOR SHOWERS AND
THUNDERSTORMS GOING THROUGH WEDNESDAY.

GROUND HAS HAD SOME TIME TO DRY OUT...WHICH KEEPS THE POTENTIAL
FOR 90 DEGREE TEMPERATURES GOING FOR THE LOWLANDS. WILL KEEP IT IN
THE UPPER 80S RANGE GIVEN THE EXPECTED CLOUD COVER...FIGURING
INSOLATION IS A NECESSITY GIVEN THE TIME OF YEAR AS WE HEAD
TOWARDS THE EQUINOX.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
THE WEAKLY FORCED PATTERN IS RELUCTANT TO CHANGE...BUT THERE ARE
SIGNS OF AN INCREASING SOUTHEAST LOW LEVEL FLOW DEVELOPING FRIDAY
NIGHT AND CONTINUING INTO SATURDAY.

THE WEAK MID LEVEL...500 MB...VORT MAX THAT WAS IN INDIANA TUESDAY
AFTERNOON...SHOULD BE EXITING TO THE EAST OF THE MOUNTAINS AT THE
START OF THIS SHORT TERM.  ALL 12Z MODEL RUNS SHOW ANOTHER 500 MB
VORT MAX IN THE WESTERN GREAT LAKES NEAR WISCONSIN AT THAT
TIME/00Z THURSDAY. IN SUCH A WEAK FLOW...WITH 500 MB HEIGHTS
BUILDING OVER THE MID ATLANTIC...HARD TO DETERMINE IF THAT WESTERN
GREAT LAKE VORT MAX WILL ACTUALLY REACH OUR VICINITY THURSDAY NIGHT
OR FRIDAY.

EVEN THE 12Z GFS SHOWING AFTERNOON HEATING RESULTS IN AN EQUILIBRIUM
LEVEL BETWEEN 35 AND 40 THSD...SO WILL BE MORE LIBERAL WITH THE 20
AND 30 POPS USING AREAL COVERAGE WITH THE SLOW MOVING CONVECTION.

WITH THAT PREVIOUSLY MENTIONED SE FLOW...WILL LEAVE POPS THROUGH
FRIDAY NIGHT ALONG OUR MOUNTAIN UPSLOPE AREAS...WITH MORE CLOUDS.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
12Z GFS SOLUTION WAS FASTER THAN THE 12Z ECMWF WITH A SHORT WAVE
AND ASSOCIATED SURFACE FRONT TRYING TO DENT THE RIDGE BY
DAY 7/TUESDAY. AT THIS DISTANCE IN TIME...WILL NOT JUMP ON THE
FASTER SOLUTION BUT STILL HAVE CHANCE POPS IN SE OHIO AND
NORTHERN WV TUESDAY AFTERNOON AND EVENING.

TRIED TO HOLD MAXIMUM TEMPERATURE DOWN A BIT FOR DAY 4/SATURDAY
IN THE SOUTHEAST UPSLOPE AREAS...OTHERWISE NO MAJOR CHANGES.

&&

.AVIATION /23Z TUESDAY THROUGH SUNDAY/...
00Z WEDNESDAY THROUGH 00Z THURSDAY...

ISOLD SHRA/TSRA THROUGH AROUND 01Z...CREATING BRIEF MVFR
CONDITIONS. OTHERWISE...VFR CONDITIONS THROUGH 06Z...WHEN IFR/LIFR
VALLEY FOG EXPECTED...PARTICULARLY IN SHELTERED VALLEYS SUCH AS AT
KEKN AND KCRW. ANY FOG WILL DISSIPATE AFTER 13Z FOR A RETURN OF
VFR CONDITIONS...WITH LIGHT SURFACE WINDS. ISOLD CONVECTION
POSSIBLE AGAIN...GENERALLY AFTER 17Z...CREATING BRIEF MVFR
CONDITIONS.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z THURSDAY...

FORECAST CONFIDENCE: MEDIUM.

ALTERNATE SCENARIOS: TIMING AND DEPTH OF FOG TONIGHT MAY VARY FROM
FORECAST.

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       21   22   23   00   01   02   03   04   05   06   07   08
EDT 1HRLY       17   18   19   20   21   22   23   00   01   02   03   04
CRW CONSISTENCY  H    H    H    H    H    H    H    M    L    L    L    L
HTS CONSISTENCY  H    H    H    H    H    H    H    M    M    M    L    L
BKW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
EKN CONSISTENCY  H    H    H    H    H    H    H    L    L    L    L    L
PKB CONSISTENCY  H    H    H    H    H    H    H    H    M    M    L    L
CKB CONSISTENCY  H    H    H    H    H    H    H    M    M    M    L    L

AFTER 00Z THURSDAY...
IFR POSSIBLE IN DENSE RIVER VALLEY FOG DURING EARLY MORNINGS.

&&

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

&&

$$
SYNOPSIS...FB/30/26
NEAR TERM...SL/26
SHORT TERM...KTB/JW
LONG TERM...FB/KTB
AVIATION...SL


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.