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000
FXUS63 KIWX 181934
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
334 PM EDT TUE JUN 18 2013

.SYNOPSIS...
ISSUED AT 331 PM EDT TUE JUN 18 2013

A WEAKENING FRONTAL BOUNDARY WILL SLOWLY DROP INTO CENTRAL INDIANA
BY THIS EVENING. A DISTURBANCE WILL DROP SOUTHEAST ALONG THE FRONT
THIS AFTERNOON...ALLOWING FOR A CHANCE OF SHOWERS AND
THUNDERSTORMS...MAINLY SOUTH OF US 24. HIGH PRESSURE WILL BUILD IN
ACROSS THE REGION WITH SEASONABLE TEMPERATURES AND DRY CONDITIONS.

&&

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 331 PM EDT TUE JUN 18 2013


MORNING STRATUS DECK ACROSS NORTHERN AREAS HAS GIVEN WAY TO STRONG
MIXING...ALLOWING TEMPS TO RECOVER QUICKLY AND GENERALLY MATCH WITH
TEMPS IN THE SOUTH WHERE SUNSHINE HAS BEEN ABUNDANT. MAIN DIFFERENCE
IN TERMS OF INSTABILITY WAS HIGHER SFC DEWPTS EXISTED IN SOUTHERN
AREAS CLOSER TO STATIONARY BOUNDARY DRAPED FROM CENTRAL ILLINOIS TO
SOUTHERN INDIANA. WIDELY SCATTERED SHOWERS/STORMS HAVE BEGUN TO
DEVELOP ALONG THIS BOUNDARY WITH THE MAIN FOCUS EXPECTED TO REMAIN
THERE AS SHORT WAVE ENERGY CONTINUES TO DRIFT SOUTHEAST INTO THE
SAME AREA. THIS MAKES FOR A DIFFICULT FORECAST FOR POPS INTO THIS
EVENING ACROSS SOUTHERN AREAS WITH BOUNDARIES TO AID IN DEVELOPMENT
FEW AND FAR BETWEEN. BEST POTENTIAL LIES WITH WHAT APPEAR TO BE LAKE
BREEZE SETUP FROM NEAR KANKAKEE IL INTO VALPO AND TOWARDS BENTON
HARBOR. A FEW RETURNS HAVE BEEN NOTED ACROSS N ILLINOIS ALONG THIS
BOUNDARY WHICH WAS DRIFTING SE. HOWEVER THIS MAY ONLY IMPACT FAR SW
LOCATIONS WITH REMAINDER OF THE AREA LEFT HIGH AND DRY. WHILE I
CAN`T RULE OUT A POP UP SHOWER OR STORMS ANYWHERE ACROSS THE
AREA...HAVE TRIMMED POPS AND CONFINED TO SW AREAS WITH GREATER
POTENTIAL. BY MID EVENING ANY THREAT WILL BE GONE WITH DRY
CONDITIONS SETTLING IN FOR THE REMAINDER OF THE PERIOD. DEWPTS IN
THE 40S AND EVEN A FEW 30S WILL MOVE SW INTO THE AREA OVERNIGHT INTO
WEDS.

&&

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 331 PM EDT TUE JUN 18 2013

A WARMING TREND AND MAINLY DRY WX REMAIN THE PRIMARY HIGHLIGHTS LATE
THIS WEEK INTO THE UPCOMING WEEKEND AS A SOUTHERN PLAINS/INTERMOUNTAIN
WEST UPPER RIDGE BUILDS NORTHEASTWARD INTO THE MIDWEST AND GREAT
LAKES. WEAK MID LEVEL DISTURBANCES SPILLING OUT OVER THE RIDGE FROM
A PACIFIC NORTHWEST/NORTHERN ROCKIES NEGATIVE HEIGHT ANOMALY WILL
INTERACT WITH A DEVELOPING INSTABILITY GRADIENT/FRONTAL ZONE TO
PRODUCE A TYPICAL MCS RING OF FIRE TYPE PATTERN ACROSS THE NORTHERN
PLAINS EAST INTO THE UPPER MIDWEST...EVENTUALLY INTO THE GREAT LAKES
BY THIS WEEKEND. THE LOCAL AREA WILL BE IN A SOMEWHAT PRECARIOUS
POSITION ON THE NORTHEAST FRINGE OF THIS FEATURE FRIDAY INTO
SATURDAY MORNING AS THE THETA-E RIDGE MIXES NORTH...ALTHOUGH EXPECT
APPROACHING ACTIVITY TO DRY UP INITIALLY LATE THURSDAY NIGHT INTO
FRIDAY GIVEN LINGERING LOW LEVEL RIDGING/DRYING OVER THE AREA. WITH
THIS AND NOSE OF LLJ FOCUSING WELL NORTHWEST OF THE FA LEFT THE
FORECAST MAINLY DRY THROUGH FRIDAY NIGHT.

THE UPPER LEVEL RIDGE AXIS WILL FOLD EAST OVER THE AREA SATURDAY AND
THEN JUST SOUTH AND EAST SUNDAY INTO EARLY NEXT AS THE NORTHERN
ROCKIES SHORTWAVE TROUGH LIFTS EAST-NORTHEAST INTO THE NORTHERN
PLAINS AND UPPER MIDWEST/ONTARIO. AN ACTIVE FRONTAL BOUNDARY WILL
LAY OUT UNDER DEEP WEST-SOUTHWEST FLOW LATER SUNDAY INTO EARLY NEXT
WEEK. A MODEL CONSENSUS FAVORS BETTER STORM CHANCES REMAINING NORTH
OF THE IWX CWA INVOF THIS SYNOPTIC FRONT FOR THESE
PERIODS...ALTHOUGH HARD TO PREDICT POSSIBLE COMPOSITE OUTFLOW
BOUNDARIES PUSHING FARTHER SOUTH FROM MCS ACTIVITY INTO AN UNSTABLE
ENVIRONMENT. LOWERED POPS IN SEVERAL PERIODS AS EXPECT MAINLY
DRY/HOT WX UNDER CAPPED RIDGE...ALTHOUGH COULD NOT PULL POPS
COMPLETELY (ESPECIALLY NORTH) GIVEN ABOVE MENTIONED MESOSCALE
UNCERTAINTIES AND PATTERN RECOGNITION. OTHERWISE...ONLY MINOR TWEAKS
TO TEMPS WITH PREFERENCE TO WARMER HIGHS OVER COOL/CLIMO BIASED
CONSALL GUIDANCE.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 331 PM EDT TUE JUN 18 2013


MVFR/IFR CIGS SHOULD NO LONGER BE AN ISSUE BY VALID TIME AS MIXING
CONTINUES TO ERODE THE STRATUS DECK DRIFTING SOUTH. CONFIDENCE IN
THUNDER CHANCES AT BOTH TAF SITES REMAINS LOW TO VERY LOW WITH
MAIN FOCUS LOOKING TO REMAIN SOUTH OF THE AREA. MAY ADD A VCTS
MENTION FOR A FEW HOURS AT KFWA TO REPLACE THE PROB30 BUT MAY ALSO
REMOVE COMPLETELY AND MONITOR TRENDS WITH ANY CONVECTION LIKELY OF
SHORT DURATION.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...BEACH HAZARDS STATEMENT THROUGH LATE TONIGHT FOR INZ003.

MI...BEACH HAZARDS STATEMENT THROUGH LATE TONIGHT FOR MIZ077.

OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 5 AM EDT WEDNESDAY FOR LMZ043-046.

&&

$$

SYNOPSIS...FISHER
SHORT TERM...FISHER
LONG TERM...STEINWEDEL
AVIATION...FISHER


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