National Weather Service National Headquarters

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRLX 270915
AFDRLX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
504 AM EDT SUN JUL 27 2014

.SYNOPSIS...
COLD FRONT WITH STRONG TO SEVERE STORMS TODAY. UPPER LEVEL
DISTURBANCES WILL AFFECT THE AREA THROUGH MONDAY...WITH LINGERING
CONVECTION. COOLER AND DRIER AIRMASS MID WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
THE KENTUCKY MESOSCALE THUNDERSTORM COMPLEX THAT SEVERELY DISTORTED
THE SYNOPTIC PATTERN YESTERDAY AND LAST NIGHT WILL DISSIPATE THIS
MORNING AS IT CONTINUES TO TRACK SOUTH AND EAST INTO LESS FAVORABLE
AIR. HOWEVER...THE EVOLUTION OF THE BOUNDARY IT SET UP FROM SOUTHERN
INDIANA INTO SOUTH CENTRAL KENTUCKY...EVIDENT IN NEW THUNDERSTORMS
EARLY THIS MORNING...WILL BE A KEY FACTOR IN ANY ALTERATION OF THE
SYNOPTIC PATTERN FORECAST BY THE MODELS TODAY. THE MODELS CONTINUE
TO ADVERTISE THAT THE IMPRESSIVE SYNOPTIC SCALE PARAMETERS AHEAD OF
A STRONG COLD FRONT MOVING ACROSS OUR AREA THIS AFTERNOON AND
EVENING WILL BE THE MAIN PLAYER. THIS MEANS THE EARLY MORNING
CONVECTION ALONG THAT BOUNDARY SHOULD DISSIPATE AS IT TRIES TO MOVE
EAST NORTHEAST LATER THIS MORNING INTO WORKED OVER AIR. THIS WILL IN
TURN AID THE CONVECTIVELY INDUCED BOUNDARY TO DISSIPATE WITH MIXING
OR LIFT IT BACK NORTH AND EAST...ALLOWING THE ATMOSPHERE TO RECOVER
AHEAD OF THE COLD FRONT. WITH HPC AND SPC CONTINUING TO GO WITH THE
SYNOPTIC THINKING...WE WILL ALSO GO WITH IT WHICH MEANS THAT SEVERE
THUNDERSTORM AND FLASH FLOOD POTENTIAL WILL CONTINUE UNTIL THE FRONT
EXITS EARLY TONIGHT. THUS...WILL KEEP THE FLASH FLOOD WATCH GOING.
WILL KEEP HIGH POPS AND MENTION SEVERE AND WATER IN THE FORECAST
UNTIL THE FRONT GO THROUGH. GIVEN THE RICH ATMOSPHERE AND ANY NUMBER
OF ADDITIONAL DISTURBANCES AHEAD OF THE MAIN SHOW WITH THE FRONT.
BELIEVE THE MODELS MAY BE TOO HIGH ON THE TEMPS TODAY...WILL KEEP
HIGHS IN THE MID TO UPPER 80S WITH ALL THE CLOUDS AND
CONVECTION.

PROBABLY A RELATIVE BREAK IN THE SHOWERS TONIGHT BEHIND THE COLD
FRONT...BEFORE YET ANOTHER COLD FRONT SWINGS DOWN MONDAY OUT OF OHIO
UNDER THE AMPLIFYING UPPER TROUGH. WILL DECREASE POPS FROM WEST TO
EAST FAIRLY EARLY TONIGHT AND DROP THUNDER POTENTIAL...BEFORE POPS
RAMP BACK UP LATE.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
SECONDARY COLD FRONT DROPS IN WITH ANOTHER REINFORCING BATCH OF
SHOWERS AND STORMS IN COOLER AIR ALOFT MONDAY AFTERNOON AND EVENING.
ADVECTION OF A COOLER AIRMASS AT THE SURFACE OCCURS IN NORTHERLY
FLOW AS THICKNESSES DROP INTO THE UPPER 550S WITH SOME SINGLE DIGIT
850MB TEMPERATURES. HIGH PRESSURE INFLUENCES FROM THE NORTHERN
PLAINS WILL BECOME THE DOMINANT FEATURE OVER OUR AREA...BUT THE
UPPER LEVEL TROUGH OVER JAMES BAY WILL KEEP THE POTENTIAL FOR WEAK
LOW PRESSURE SYSTEMS TO DROP THROUGH THE GREAT LAKES. THROUGH THE
END OF THE SHORT TERM...THE FORECAST IS PRIMARILY DRY WITH A COOL
END TO THE MONTH OF JULY.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
HIGH PRESSURE BEHIND THE COLD FRONT TAKES CONTROL LATER MONDAY NIGHT
THROUGH THE MIDDLE OF NEXT WEEK WITH NEAR NORMAL TEMPERATURES.

BLENDED HPC WITH PREVIOUS FORECAST NUMBERS AS THEY LOOK
REPRESENTATIVE UNDER HIGH PRESSURE AND SLIGHTLY COOLER NORTHERLY
FLOW.

&&

.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --
09Z SUNDAY THRU 06Z MONDAY...
5 AM UPDATE...CUT WAY BACK ON CONVECTION THRU 14Z...JUST SCATTERED
SHOWERS POSSIBLE. THINGS RAMP UP AGAIN SUNDAY. MVFR CLOUDS/FOG THRU
12Z IN RAIN COOLED AIR FROM PREVIOUS CONVECTION...MAINLY AT BKW AND
EKN...OTHERWISE VFR CEILINGS.

ON SUNDAY...A STRONG COLD FRONT REACHES THE OHIO RIVER BY 00Z AND
THE MOUNTAINS AROUND 03Z. WITH A VERY UNSTABLE ATMOSPHERE ON SUNDAY
AHEAD OF THE FRONT...MORE THUNDERSTORMS ARE LIKELY AFTER 14Z...AFTER
A MINIMUM OF MORNING CONVECTION. SOME OF THE STORMS MAY BE SEVERE.
OUTSIDE OF CONVECTION EXPECT VFR CEILINGS.

AFTER 00Z MVFR CEILINGS GRADUALLY SPREADING SOUTHEASTWARD FROM
OHIO...ASSOCIATED WITH A SECONDARY COLD FRONT AND SCATTERED SHOWERS.
LOOK FOR TREND TO MVFR CEILINGS AND SCATTERED SHOWERS MOST OF AREA
BY 06Z.

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

FORECAST CONFIDENCE: LOW

ALTERNATE SCENARIOS: TIMING...COVERAGE...AND SEVERITY OF
THUNDERSTORMS TODAY 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                    SUN 07/27/14
UTC 1HRLY       08   09   10   11   12   13   14   15   16   17   18   19
EDT 1HRLY       04   05   06   07   08   09   10   11   12   13   14   15
CRW CONSISTENCY  H    H    H    H    H    H    H    H    H    M    M    M
HTS CONSISTENCY  H    H    H    H    H    H    H    H    H    M    M    M
BKW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
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    M    M    M
CKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H

AFTER 06Z MONDAY...
NO SIGNIFICANT IFR CONDITIONS EXPECTED.
-- End Changed Discussion --

&&

.HYDROLOGY...
A SERIES OF UPPER LEVEL DISTURBANCES AHEAD OF A COLD FRONT MAY
PRODUCE AREAS OF HEAVY RAINFALL TODAY AND EARLY TONIGHT. AMPLE
MOISTURE IN THE LOW LEVELS AND STRONG FORCING ALOFT CAN BE CONDUCIVE
TO FLASH FLOODING. THIS SCENARIO COULD PRODUCE FLASH FLOODING OF
STREETS...CREEKS...SMALL STREAMS AND LOW LYING AREAS WITH REPETITIVE
SHOWERS OR STORMS. A FLASH FLOOD WATCH IS IN EFFECT FROM MIDNIGHT
TONIGHT THROUGH LATE SUNDAY NIGHT FOR OUR ENTIRE CWA.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR WVZ005>011-013>020-
     024>040-046-047.
OH...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR OHZ066-067-075-076-
     083>087.
KY...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR KYZ101>103-105.
VA...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR VAZ003-004.

&&

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

HYDROLOGY...JMV