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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KILN 170145
AFDILN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
945 PM EDT WED APR 16 2014

.SYNOPSIS...
HIGH PRESSURE WILL REMAIN IN CONTROL OF OUR WEATHER THROUGH THURSDAY
AS IT SLIDES OFF TO THE EAST. MILDER AIR WILL RETURN AS WINDS BECOME
SOUTHERLY ON THE BACK SIDE OF THIS RETREATING HIGH. SHOWERS WILL BE
POSSIBLE FRIDAY AS A WEAK FRONT PUSHES THROUGH THE OHIO VALLEY.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
-- Changed Discussion --
VERY FEW CHANGES WERE NEEDED FOR THE FORECAST TONIGHT...WITH A
FROST ADVISORY REMAINING IN EFFECT FOR THE AREAS WHERE THE
FROST/FREEZE PROGRAM IS ACTIVE. 18Z MODEL RUNS AND HOURLY UPDATES
FROM RAP/HRRR MODELS ARE STILL INDICATING TEMPERATURES WITHIN A
COUPLE DEGREES IN EITHER DIRECTION FROM THE CURRENT
FORECAST...WITH THE RAP GENERALLY SLIGHTLY HIGHER...BUT THE
HRRR/NAM ARE SHOWING ISOLATED AREAS DROPPING AS LOW AS THE UPPER
20S. THE DRY AIR MASS MIGHT OTHERWISE SUPPORT MORE WIDESPREAD
CONDITIONS IN THE LOWER 30S...BUT WITH SOME WIND REMAINING IN
PLACE AND HIGH CLOUDS OVER THE REGION...THE RADIATIONAL COOLING
CONDITIONS ARE NOT PERFECT. SOME SKY GRID ADJUSTMENTS WERE MADE TO
FOCUS SOME DETAIL ON THE MAIN BANDS OF CIRRUS. OTHERWISE...GRIDS
WERE UPDATED FOR TRENDS AND PUBLISHED.

PREVIOUS FORECAST DISCUSSION >
WESTERLY MID LEVEL FLOW WITH SURFACE HIGH PRESSURE SLIDING OFF TO
THE EAST BECOMING CENTERED OVER NEW ENGLAND BY THURSDAY MORNING. A
SOUTHERLY RETURN FLOW WILL BEGIN TO DEVELOP LATE TONIGHT ON THE BACK
SIDE OF THIS RETREATING SFC HIGH. SKIES WILL START OUT MAINLY CLEAR
THIS EVENING WITH AN INCREASE IN HIGH LEVEL CLOUDS OVERNIGHT.
QUESTION REVOLVES AROUND WHETHER WIND/CLOUDS WILL MITIGATE FROST
DEVELOPMENT TONIGHT. EXPECT THAT SOME FROST WILL DEVELOP ESPECIALLY
IN PROTECTED AREAS. WILL CONTINUE FROST ADVISORY ACRS THE SOUTH
WHERE THE SEASON HAS STARTED. HAVE TAKEN FROST MENTION OUT OF
WEST CENTRAL OHIO WHERE WINDS PICK UP IN RESPONSE TO THE INCREASING
GRADIENT. LOWS EXPECTED TO RANGE FROM THE LOWER 30S NE TO THE MID
30S SOUTH.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
A RETURN SOUTHERLY FLOW WILL DEVELOP BETWEEN RETREATING SFC HIGH
PRESSURE AND WEAK COLD FRONT TO OUR WEST. THIS SRLY FLOW WILL ALLOW
TEMPERATURES TO MODERATE TO READINGS SLIGHTLY ABOVE NORMAL ON
THURSDAY. EXPECT A FAIR AMOUNT OF HIGH LEVEL CLOUDS MAINLY EARLY
AND THEN DECREASING AS THE OHIO VALLEY GETS INTO THE WARM SECTOR.
EXPECT HIGHS TO RANGE FROM THE LOWER 60S NE TO THE UPPER 60S SW.

MID LEVEL SHORTWAVES TO PHASE TO OUR WEST WITH A LONG WAVE TROF AXIS
PIVOTING THRU THE OHIO VALLEY FRIDAY/FRIDAY NIGHT. EXPECT SOME
INCREASE IN CLOUDS THICKEST ACRS THE WEST LATE THURSDAY NIGHT. WITH
SOME WIND AROUND 5 KTS AND INCREASE IN CLOUDS EXPECT THURSDAY NIGHTS
LOWS TO BE CLOSE TO NORMAL...RANGING FROM NEAR 40 NE TO THE LOWER/MID
40S SW.

WEAK SFC COLD FRONT TO PIVOT EAST THRU ILN/S FA FRIDAY/FRIDAY
EVENING. MODEL SOLN DIFFERENCES EXIST REGARDING MOISTURE/TIMING WITH
THIS WEAK FRONT. MAIN SFC LOW WELL TO OUR NORTH AND FORCING IS VERY
WEAK OVER ILN/S FA. WILL CONTINUE TO LIMIT POPS TO CHC IN THE WEST
FRIDAY AFTN AND THEN ONLY ALLOW SLIGHT CHC IN THE SOUTHEAST. EXPECT
HIGHS FROM THE LOWER 60S NW TO THE UPPER 60S SE FRIDAY. LOWS
FRIDAY NIGHT TO RANGE FROM THE UPPER 30S NW TO THE MID 40S SE.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE STRETCHING FROM SOUTHEAST CANADA THROUGH THE GREAT
LAKES AND OHIO VALLEY WILL KEEP DRY WEATHER OVER THE AREA SATURDAY
AND SUNDAY. A COLD FRONT WILL ENTER THE REGION MONDAY. GFS AND
ECMWF BOTH INDICATE THE FRONT...BUT DIFFERENCES IN TIMING
EXIST...WITH GFS FASTER AND ECMWF OFFERING A SLOWER SOLUTION.
SPLIT THE DIFFERENCE BETWEEN MODELS AND WENT WITH A MODEL
BLEND...WHICH YIELDS THE LIKELIHOOD FOR SHOWERS MONDAY AND MONDAY
NIGHT. WITH MODELS SHOWING SCANT INSTABILITY AND RATHER WEAK WIND
FIELDS ALONG THE FRONT...DECIDED TO OMIT THUNDER. HIGH PRESSURE
AND DRY AIR ARE EXPECTED TO RETURN FOR TUESDAY AND WEDNESDAY.

TEMPERATURES WILL START OUT A BIT COOL ON SATURDAY WITH HIGHS
FORECAST TO BE IN THE UPPER 50S TO MID 60S. DUE TO A MODEST AMOUNT
OF WARM ADVECTION...HIGHS FOR SUNDAY THROUGH WEDNESDAY ARE
ANTICIPATED TO AVERAGE IN THE NEAR NORMAL MID AND UPPER 60S.

&&

.AVIATION /02Z THURSDAY THROUGH MONDAY/...
WITH HIGH PRESSURE TO THE EAST...AND LOW PRESSURE TO THE
WEST...SOUTHERLY FLOW WILL DEVELOP OVER THE OHIO VALLEY ON
THURSDAY. SOUTHEASTERLY WINDS WILL TURN SOUTH BY LATE MORNING
TOMORROW...WITH WINDS GENERALLY REMAINING IN THE 5-10 KNOT RANGE.
A FEW OCCASIONAL GUSTS UP TO AROUND 15 KNOTS WILL BE POSSIBLE.

WITH A FAIRLY DRY AIR MASS IN PLACE...CLOUDS WILL GENERALLY BE
LIMITED TO PATCHES OF CIRRUS AND CIRROSTRATUS. A FEW CUMULUS
COULD DEVELOP NEAR DAYTON...BUT VFR CONDITIONS ARE EXPECTED
THROUGH THE PERIOD,

OUTLOOK...MVFR CEILINGS AND VISIBILITIES ARE POSSIBLE MONDAY.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...FROST ADVISORY FROM 2 AM TO 9 AM EDT THURSDAY FOR OHZ077>082-
     088.
KY...FROST ADVISORY FROM 2 AM TO 9 AM EDT THURSDAY FOR KYZ089>100.
IN...FROST ADVISORY FROM 2 AM TO 9 AM EDT THURSDAY FOR INZ073>075-
     080.

&&

$$
SYNOPSIS...AR
NEAR TERM...HATZOS/AR
SHORT TERM...AR
LONG TERM...CONIGLIO
AVIATION...HATZOS