-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KILN 171056
AFDILN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
656 AM EDT FRI MAY 17 2013

.SYNOPSIS...
A FRONTAL BOUNDARY WILL REMAIN ACROSS THE REGION INTO THE
WEEKEND...KEEPING UNSETTLED CONDITIONS OVER THE AREA.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A SIZABLE AREA OF FOG HAS FORMED OVER MUCH OF THE REGION THIS
MORNING DUE TO LIGHT/CALM WINDS AND AMPLE GROUND/LOW LEVEL
MOISTURE. A DENSE FOG ADVISORY HAS BEEN ISSUED FOR A GOOD PORTION
OF THE REGION...EXCEPT FOR THE FAR NORTH AND PARTS OF THE WRN/SRN
CWFA.

OTHERWISE...A FRONTAL BOUNDARY WAS DRAPED ACRS THE NRN CWFA THIS
MORNING. THIS FRONT WILL MOVE SLIGHTLY NORTH TODAY WITH DIURNAL
HEATING...WHILE AN UPR LVL LOW APPROACHES FROM THE SOUTHWEST.
FORCING TODAY IS WEAK SO CONVECTION SHOULD BE DIURNALLY
DRIVEN...PEAKING DURING THE AFTN HOURS. AM EXPECTING THE BEST
COVERAGE ACRS THE SRN ZONES WHERE THE DEEPEST MOISTURE EXISTS.
TEMPERATURES WILL BE CLOUD AND RAIN DEPENDENT...BUT SHOULD
GENERALLY RANGE FROM THE UPPER 70S TO THE LOWER 80S.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
HAVE TAKEN A BLEND OF THE 17.00Z GFS AND THE 16.12Z ECMWF FOR THE
SHORT TERM FORECAST AS THEY SEEM TO DEPICT THE MOVEMENT OF THE
APPROACHING UPR LVL LOW THAN THE NAM/CMC. HAVE TAKEN INTO ACCOUNT
THE GFS CONVECTIVE FEEDBACK ISSUES AS WELL.

FOR TONIGHT INTO SATURDAY...AN UPR LVL LOW WILL SLOW PUSH INTO THE
OUR REGION...HUGGING NEAR THE OHIO RIVER. AT THE SAME TIME...THE
AFOREMENTIONED WEAK FRONTAL BOUNDARY WILL OSCILLATE AND INTERACT
WITH THIS UPR LVL FEATURE. WE WILL LIKELY SEE A DECREASE IN
CONVECTION THIS EVENING DUE TO THE LOSS OF DAYTIME HEATING...WITH
PERHAPS AN UPTICK ACRS THE FAR SWRN CWFA TOWARD MORNING IN
RESPONSE TO THE APPROACHING LOW. ON SATURDAY...THE COMBINATION OF
THE UPR LOW ACRS THE SOUTH WILL KEEP THE HIGHEST THREAT FOR
SHOWERS/STORMS  THERE WITH DECREASING CHANCES TO THE NORTH.

FOR SATURDAY NIGHT INTO SUNDAY...UPR LVL LOW IS FORECAST TO WEAKEN
AND OPEN UP AS A WAVE WHILE IT SLOWLY PUSHES EAST TOWARD THE
CENTRAL APPALACHIANS. WILL HAVE TO KEEP A CHANCE OF SHOWERS AND
THUNDERSTORMS GOING...BUT COVERAGE SHOULD BE LESS THAN SATURDAY.

FOR SUNDAY NIGHT...A MID LVL RIDGE TRIES TO BUILD INTO THE OHIO
VALLEY WHILE THE WEAK LOW CONTINUES TO MOVE EAST. HAVE ALLOWED THE
THREAT FOR SHOWERS/STORMS TO END EARLY IN THE EVENING WITH SKIES
BECOMING PARTLY CLOUDY.

AS FOR TEMPERATURES...THEY SHOULD BE HELD DOWN SOME ON SATURDAY
DUE TO CLOUDS AND THE RAIN THREAT...PEAKING INTO THE MID AND UPPER
70S. ON SUNDAY...HIGHS WILL RANGE FROM THE UPPER 70S SOUTHEAST TO
THE LOWER 80S WEST.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
THERE IS THE POTENTIAL FOR A FEW THUNDERSTORMS TO DEVELOP ACROSS
THE FA ON MONDAY HOWEVER BELIEVE THAT THE COVERAGE OF THE
PRECIPITATION WILL BE LOW AND THEREFORE LIMITED PRECIPITATION
CHANCES TO A SLIGHT CHANCE. ADDITIONAL PRECIPITATION WILL BEGIN TO
WORK INTO WESTERN PORTIONS OF THE FA TUESDAY AFTERNOON AS AN AREA
OF LOW PRESSURE BEGINS TO APPROACH THE REGION. MONDAY AND TUESDAY
WILL HAVE THE WARMEST TEMPERATURES WITH HIGHS IN THE 80S ACROSS
THE ENTIRE FORECAST AREA. A COLD FRONT WILL MOVE THROUGH THE FA
WEDNESDAY NIGHT INTO THURSDAY MORNING. COOLER AIR WILL BE IN PLACE
FOR THURSDAY WITH HIGH TEMPERATURES IN THE 60S.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --
COPIOUS LOW-LEVEL MOISTURE HAS ALLOWED FOR WIDESPREAD DENSE FOG
THIS MORNING...AFFECTING ALL TAF SITES EXCEPT KCVG...AS WELL AS
LOW CEILINGS (IN SOME CASES BELOW AIRPORT MINIMUMS). GIVEN THE
THICKNESS OF THE MOISTURE...THESE POOR CONDITIONS ARE NOT EXPECTED
TO IMPROVE IN AN OVERLY RAPID FASHION. THUS...LIFTING TO VFR
CONDITIONS HAS BEEN SLOWED DOWN IN THE TAFS UNTIL 15Z...BUT
THERE IS POTENTIAL FOR THE LOW CEILINGS TO BREAK UP SLOWLY AND
PERHAPS EXTEND EVEN A LITTLE BEYOND THAT.

BY LATE AFTERNOON AND INTO THE EVENING...PRECIPITATION IS EXPECTED
TO DEVELOP NEAR THE CINCINNATI TAF SITES. WITH INCREASING
CONFIDENCE FROM MULTIPLE COMPUTER MODELS...PREVAILING SHOWERS HAVE
BEEN INCLUDED IN THE TAFS...AND THIS ACTIVITY WILL LIKELY CONTAIN
EMBEDDED THUNDERSTORMS AS WELL. SHOWERS AND STORMS MAY AFFECTK
DAY/KILN...BUT THIS IS SOMEWHAT LESS LIKELY. THE COLUMBUS TAF
SITES WILL BE FURTHER AWAY FROM THE PREDICTED AREA OF
DEVELOPMENT...SO CONFIDENCE IS EVEN LOWER THAT ANYTHING WILL
AFFECT THE TAF SITES THERE. ALTHOUGH THE LATE EVENING AND
OVERNIGHT PERIOD IS CURRENTLY DRY IN THE TAFS...THERE DOES APPEAR
TO BE SOME POTENTIAL FOR LINGERING SHOWERS...ESPECIALLY IN THE
SOUTH.

ALTHOUGH VFR LOW AND MID CLOUD COVER WILL BE MORE PLENTIFUL
TONIGHT AS OPPOSED TO THIS PAST OVERNIGHT PERIOD...THERE WILL
STILL BE ENOUGH MOISTURE IN PLACE TO ALLOW VISIBILITIES TO DROP.
MVFR CONDITIONS (IFR AT KLUK) HAVE BEEN PLACED IN THE TAFS NEAR
THE END OF THE FORECAST PERIOD. AS IT HAS BEEN THIS MORNING...IF
THERE ARE BREAKS IN THESE CLOUDS...CONDITIONS WILL BE FAVORABLE
FOR IFR/LIFR CONDITIONS TO FORM RELATIVELY QUICKLY.

OUTLOOK...THUNDERSTORMS ARE POSSIBLE THROUGH SUNDAY...PRIMARILY
IN THE AFTERNOON AND EVENING. MVFR TO IFR VISIBILITIES ARE POSSIBLE
FRIDAY...SATURDAY AND SUNDAY NIGHTS.
-- End Changed Discussion --

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...DENSE FOG ADVISORY UNTIL 10 AM EDT THIS MORNING FOR OHZ042>046-
     051>056-060>065-070>074-077>082-088.
KY...DENSE FOG ADVISORY UNTIL 10 AM EDT THIS MORNING FOR KYZ091>093.
IN...NONE.

&&

$$
SYNOPSIS...HICKMAN
NEAR TERM...HICKMAN
SHORT TERM...HICKMAN
LONG TERM...NOVAK
AVIATION...HATZOS