000
FXUS63 KPAH 172237
AFDPAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PADUCAH KY
537 PM CDT FRI MAY 17 2013

.UPDATE...
ISSUED AT 533 PM CDT FRI MAY 17 2013

UPDATED FOR 00Z AVIATION ONLY.


&&

.SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT)
ISSUED AT 309 PM CDT FRI MAY 17 2013

AS AN H5 LOW TRACKS TO THE NORTH AND WEST OF OUR CWA TONIGHT...
SHOWER AND THUNDERSTORM CHANCES SHOULD SLOWLY DIMINISH FROM WEST TO
EAST. WRAP AROUND MOISTURE AND RIPPLES OF ENERGY ON THE BACK SIDE OF
THE LOW MAY PRODUCE A CHANCE FOR SHOWERS AND THUNDERSTORMS OVER THE
NORTHEAST HALF OF THE CWA ON SATURDAY.

SATURDAY NIGHT MODELS ARE FAIRLY CONSISTENT IN THAT THEY SHOW A
NW-SE ORIENTED SFC TROUGH DRAPED ACROSS OUR CWA...AN H5 RIDGE
BUILDING ACROSS THE AREA...AND A NW-SE ORIENTED BAND OF LIGHT
PRECIPITATION/QPF. ORDINARILY WITH A RIDGE BUILDING OVERHEAD IT
TENDS TO SQUASH/SUPPRESS ANY CHANCES FOR PRECIPITATION...BUT WITH
THE PRESENCE OF THE SFC TROUGH AND THE FACT THAT ALL MODELS WERE
CRANKING OUT PRECIP...DECIDED TO ADD IT.

WITH THE RIDGE AXIS MIGRATING EASTWARD ACROSS THE AREA ON SUNDAY...
PRECIP MAY LINGER OVER THE EASTERN THIRD OF THE CWA BEFORE ENDING.
SUNDAY NIGHT AS THE RIDGE AXIS SHIFTS EAST OF THE AREA...IT WILL
ALLOW PRECIP CHANCES TO MAKE THEIR WAY BACK INTO THE FAR
NORTHWESTERN AND WESTERN SECTIONS OF OUR CWA AS THE NEXT WEATHER
APPROACHES FROM THE CENTRAL PLAINS.

.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 309 PM CDT FRI MAY 17 2013

GFS AND ECMWF BOTH SHOW LOW PRESSURE OVER THE NORTHERN PLAINS/UPPER
MIDWEST AT 00Z TUESDAY.  ECMWF IS FASTER BRINGING THE ASSOCIATED
COLD FRONT INTO THE PAH FORECAST AREA...WITH THE BEST CHANCES FOR
SHOWERS AND THUNDERSTORMS TUESDAY NIGHT INTO WEDNESDAY.  12Z GFS IS
ABOUT 12 HOURS SLOWER...SHOWING WIDESPREAD QPF WEDNESDAY INTO
WEDNESDAY NIGHT.  THE 06Z GFS MATCHED A LITTLE BETTER WITH THE 00Z
AND LATEST ECMWF RUN...SO WILL LEAN A LITTLE MORE TOWARD THE LATEST
ECMWF SOLUTION...AND WENT WITH SMALL POPS FOR SHOWERS AND STORMS IN
OUR FAR WEST AND NORTHWEST COUNTIES MONDAY...WITH INCREASING POPS
FROM WEST TO EAST MONDAY NIGHT INTO TUESDAY.  STUCK WITH LIKELY POPS
FOR MOST OF THE PAH FORECAST AREA TUESDAY NIGHT...AND LIKELY POPS
EAST TO LOW CHANCE POPS WEST BY WEDNESDAY.  THOUGH TIMING IS NOT TOO
CERTAIN...MODELS ARE AT LEAST IN AGREEMENT WITH A FRONTAL PASSAGE IN
THE TUESDAY TO WEDNESDAY TIME FRAME.  KEPT SOME SLIGHT TO LOW CHANCE
POPS INTO WEDNESDAY NIGHT AND THURSDAY AS AN UPPER LOW/TROF SLOWLY
TRUDGES THROUGH THE SOUTHERN GREAT LAKES REGION.

AFTER THURSDAY...LATEST ECMWF HAS DEVIATED QUITE A BIT FROM ITS
PREVIOUS SOLUTION.  THE 00Z ECMWF ALONG WITH THE 06Z AND 12Z GFS
RUNS SHOW HIGH PRESSURE BUILDING SOUTHWARD OUT OF EASTERN CANADA
INTO THE GREAT LAKES REGION.  THE 12Z ECMWF IS FARTHER EAST AND LESS
AGGRESSIVE WITH THIS FEATURE...WHICH KEEPS THE PAH FA ON THE EASTERN
SIDE OF A WEAK SURFACE TROF.  PREFER TO LEAN TOWARD THE GFS AND
PREVIOUS ECMWF RUNS FOR NOW...KEEPING THE AREA IN A DRY AND COOLER
PATTERN FOR FRIDAY AND INTO NEXT WEEKEND. TIME WILL TELL.

&&

.AVIATION...
ISSUED AT 533 PM CDT FRI MAY 17 2013

VISIBLE SATELLITE LOOP INDICATES MOST OF THE CLOUD COVER DIURNAL.
THEREFORE GOT RID OF CEILINGS OVERNIGHT...BUT THIS COULD LEAD TO
FASTER AND MORE DENSE FOG DEVELOPMENT HAVE PREDOMINANT
RESTRICTIONS AFTER MIDNIGHT BUT ONLY MVFR FOR NOW. WILL MONITOR
CLOSELY FOR UPDATES ON VSBY.

&&

.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&

$$

UPDATE...KH
AVIATION...KH