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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
156 AM EDT SAT AUG 29 2015

.SYNOPSIS...
A WEAK WARM FRONT WILL LIFT NORTH ACROSS THE AREA ON SATURDAY AND
THEN A WEAK UPPER LEVEL DISTURBANCE WILL PUSH EAST ACROSS THE
REGION THROUGH SUNDAY. THIS WILL RESULT IN AN INCREASING CHANCE
OF SHOWERS AND THUNDERSTORMS OVER THE WEEKEND. SEASONABLE
TEMPERATURES ARE EXPECTED THROUGH SUNDAY.

&&

.NEAR TERM /THROUGH TODAY/...
HIGH PRESSURE WILL CONTINUE TO SHIFT OFF TO THE EAST...ALLOWING
FOR AN INCREASE IN PRIMARILY HIGH LEVEL CLOUDS OVERNIGHT. LOWS
TONIGHT WILL RANGE FROM THE UPPER 50S NORTHEAST TO THE LOWER 60S
SOUTHWEST.

&&

.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
A WEAK WARM FRONT WILL LIFT NORTH ACROSS THE AREA THROUGH THE
MORNING HOURS ALLOWING FOR A WARMER AND MORE MOIST AIR MASS
TO OVERSPREAD THE REGION BY AFTERNOON. THIS WILL LEAD TO
INCREASING INSTABILITIES AS WE PROGRESS THROUGH THE DAY. THE NAM
REMAINS CONSIDERABLY HIGHER THAN THE GFS WITH ITS
INSTABILITIES...BUT BOTH ARE INDICATING THAT THE BEST
INSTABILITIES WILL BE ACROSS NORTHWEST PORTIONS OF OUR FA. SINCE
FORCING IS FAIRLY WEAK...THINK ANY DEVELOPMENT WILL BE ISOLATED
AND WILL LIMIT SLIGHT CHANCE POPS TO ABOUT THE NORTHWEST HALF OF
OUR FA...IN THE AREA OF SOMEWHAT DEEPER MOISTURE AND BETTER
INSTABILITIES.

A WEAKENING UPPER LEVEL TROUGH WILL WORK ITS WAY SLOWLY EAST
TOWARD OUR AREA SATURDAY NIGHT THROUGH SUNDAY WITH AN ASSOCIATED
WEAK COLD FRONT WASHING OUT AS IT PUSHES INTO OUR AREA THROUGH THE
DAY ON SUNDAY. THE COMBINATION OF THIS AND A CONTINUED MOIST AND
UNSTABLE AIR MASS...WILL LEAD TO AN INCREASING CHANCE OF SHOWERS
AND THUNDERSTORMS INTO SUNDAY BEFORE DECREASING SUNDAY NIGHT.

HIGHS ON SUNDAY WILL AGAIN BE IN THE LOW TO MID 80S.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
WITH A WEAK FLOW PATTERN ALOFT...MODELS CONTINUE TO EXHIBIT ERRATIC 
RUN TO RUN BEHAVIOR AND SIGNIFICANT SPREAD IN THEIR HANDLING OF 
SYNOPTIC FEATURES THROUGH THE EXTENDED PERIOD...ESPECIALLY AS THE 
REMNANTS OF ERIKA COME INTO PLAY. TO ACCOUNT FOR MODEL 
DISCREPANCIES...HAVE USED A BLEND OF SOLUTIONS AND RELIED ON 
ENSEMBLE MEANS. 

A MID LEVEL SHORTWAVE WILL LIFT FROM THE GULF OF MEXICO INTO THE MID 
ATLANTIC STATES EARLY MONDAY. UNDER THE INFLUENCE OF THIS FEATURE 
THE 28.00Z ECMWF RUN FEATURED AN UPPER LEVEL SHORTWAVE MORPHING INTO 
A SLOW MOVING CUTOFF LOW OVER THE GREAT LAKES REGION THROUGH EARLY 
WEDNESDAY. THE 28.12Z ECMWF RUN IS A COMPLETELY DIFFERENT STORY AND 
MUCH MORE IN AGREEMENT WITH THE GFS...SHOWING THE OHIO VALLEY AND 
GREAT LAKES REGION UNDER AN AMPLIFIED MID/UPPER LEVEL RIDGE ON 
MONDAY. PRECIP CHANCES WILL TAPER OFF MONDAY AFTERNOON AS HIGH 
PRESSURE BUILDS INTO THE AREA. 

THE MID/UPPER RIDGE WILL FLATTEN OUT A BIT TUESDAY THROUGH THURSDAY 
WHICH IS WHEN MODEL SOLUTIONS DIVERGE SIGNIFICANTLY UNDER THE 
INFLUENCE OF WEAK FLOW ALOFT TO AROUND 400MB. FORECAST DETAILS START 
TO BECOME MURKY AS A RESULT. SYNOPTIC FORCING WILL BE LACKING BUT 
GIVEN THE UNSEASONABLE WARMTH AND MOISTURE /HIGH TEMPS 5+ DEGREES 
ABOVE NORMAL AND PWATS 1 TO 2 STANDARD DEVIATIONS ABOVE NORMAL/ HAVE 
GONE WITH SLIGHT CHANCE DIURNAL POPS EACH DAY. HIGHS WILL GENERALLY 
BE IN THE MID TO UPPER 80S WITH LOWS IN THE MID TO UPPER 60S.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
WITH THE EXCEPTION OF SOME MVFR VSBYS AT KLUK...VFR CONDITIONS
WILL BE FOUND OVER THE REGION...EVEN AS SHOWERS BECOME MORE
PREVALENT OVER THE REGION IN THE 18-0Z TIME FRAME THIS
AFTERNOON. THESE SHOWERS SHOULD PRIMARILY AFFECT NORTHERN TAF
SITES BUT THERE IS NOT ANY PARTICULAR FEATURE THAT THE MODELS ARE
PICKING UP TO DEFINITIVELY SAY WHEN OR WHERE THEY MAY OCCUR. THAT
BEING SAID...HAVE VFR SHOWERS AT KCVG/KLUK TOWARDS 6Z. THE VFR
SHOWERS AT KDAY AND KILN IN THE LATE DAY WITH VICINITY AFTER 0Z.
SIMILAR AT KCMH/KLCK WITH VC STARTING AT 22Z. THE SOUTH-SOUTHWEST
WIND WILL TURN SOUTHEAST AND DECREASE TO <5KT AFTER ABOUT 0Z AS
THE GRADIENT RELAXES.

OUTLOOK...THUNDERSTORMS POSSIBLE SUNDAY.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.

&&

$$
SYNOPSIS...JGL
NEAR TERM...JGL
SHORT TERM...JGL
LONG TERM...KURZ
AVIATION...FRANKS

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