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000
FXUS63 KIWX 221027
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
627 AM EDT WED MAY 22 2013

.SYNOPSIS...
ISSUED AT 355 AM EDT WED MAY 22 2013

LOW PRESSURE OVER NORTHEAST IOWA THIS MORNING WILL MOVE EAST
ACROSS SOUTHERN LOWER MICHIGAN TODAY AND TO SOUTHERN ONTARIO
TONIGHT. A WEAK COOL FRONT WILL TRAIL TO THE SOUTH OF THE LOW AND
MOVE EAST ACROSS SOUTHERN MICHIGAN... INDIANA... AND MOST OF OHIO BY
THURSDAY MORNING... WHILE A SECOND STRONGER COLD FRONT DROPS SOUTH
ACROSS THE UPPER GREAT LAKES. SCATTERED SHOWERS AND THUNDERSTORMS
ARE EXPECTED ALONG AND AHEAD OF THE FIRST COOL FRONT... WHILE
SCATTERED SHOWERS MAY ACCOMPANY THE SECOND COLD FRONT.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 440 AM EDT WED MAY 22 2013

UPR LOW OVER SRN MN EXPECTED TO MOVE ESE TODAY/TNGT AND GRDLY
SHEAR OUT/MERGE WITH NRN STREAM TROF DROPPING SOUTH FROM HUDSON
BAY TO THE UPR GRTLKS. ASSOCIATED BROAD SFC LOW SHOULD MOVE EAST
FROM IA ACROSS SRN LWR MI TODAY AND INTO SRN ONTARIO TONIGHT WITH
AN ACCOMPANYING WK COOL FRONT MOVG EAST ACROSS OUR CWA.
COMBINATION OF WK UVM ASSOCIATED WITH THESE FEATURES AND SOME
DIURNAL DESTABILIZATION EXPECTED TO RESULT IN SHOWERS/TSTMS IN THE
AREA... MAINLY THIS AFTN. AFTN CAPE EXPECTED TO BE 1000-1500J/KG
WITH 30-35KT 0-6KM SHEAR AND STEEP LOW LEVEL LAPSE RATES. THIS MAY
ALLOW SOME OF THE STORMS TO BECOME SEVERE WITH DAMAGING WINDS AND
LARGE HAIL PSBL THIS AFTN... PARTICULARLY OVER NW OH WHERE FROPA
WILL BE LATER ALLOWING FOR BETTER OPPORTUNITY TO DESTABILIZE.

A STRONGER CDFNT ASSOCIATED WITH THE APCHG NRN STREAM TROF SHOULD
DROP INTO SRN LM BY DAWN THU. FORCING TONIGHT HWVR SHOULD BE
WEAKER AS MID/UPR LEVEL WIND FIELD OVER THE AREA GRDLY WEAKENS AS
UPR LOW SHEARS OUT. GIVEN THIS SCENARIO... STAYED CLOSE TO
INHERITED CHC POP GRIDS FOR TONIGHT.

HIGHS TODAY GENERALLY FCST A FEW DEGREES ABOVE MOS BASED ON
RECENT COOL BIAS AND MILD START TO THE DAY. COOL FRONT SHOULD
RESULT IN A LITTLE LOWER MINS TONIGHT... RANGING FROM AROUND 50
NEAR LAKE MICHIGAN TO AROUND 60 FAR SE.

&&

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 440 AM EDT WED MAY 22 2013

A SECONDARY UPPER LEVEL TROF WILL MOVE SOUTHEAST ACROSS THE WESTERN
GREAT LAKES REGION THURSDAY AS COOLER AIR SPREADS SOUTHEAST. THE
UPPER LEVEL SUPPORT SHOULD BE SUFFICIENT TO PRODUCE SHOWERS...
ALTHOUGH THERE SHOULD BE A WELL DEFINED NW EDGE/ENDING OF THE
PRECIPITATION GIVEN THE SUBSIDENCE BEHIND THE TROF. PUT SOME DETAIL
IN THE GRIDS IN THIS REGARD THURSDAY WITH THE BEST CHANCE FOR RAIN
EARLY IN THE DAY. ADDED PATCHY FROST NORTHERN AREAS THURSDAY NIGHT.
SKIES SHOULD CLEAR WITH WINDS BECOMING LIGHT MOST AREAS. OTHERWISE...
KEPT THE REST OF THE FORECAST DRY. SPECTRAL MODELS PROVIDING A RANGE
OF HANDLING THE SHORT WAVE ENERGY MOVING EAST AS THE UPPER LEVEL
RIDGE AMPLIFIES OVER THE EASTERN HALF OF THE CONUS. THE ECMWF KEEP
THE ENTIRE PERIOD DRY AND APPEARS REASONABLE WITH THIS SOLUTION.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 626 AM EDT WED MAY 22 2013

AN AREA OF SHRA OVER INDIANA AHEAD OF SHRTWV LIFTING N-NE AROUND
UPR MIDWEST LOW IS EXPECTED TO IMPACT THE TERMINALS THIS MORNING
WITH MVFR CONDITIONS. PREDOMINANTLY VFR CONDITIONS EXPECTED THIS
AFTN BUT DIURNAL DESTABILIZATION AND APCHG COOL FRONT WILL LIKELY
RESULT IN SCT TS WITH LOCALLY LOWER FLYING CONDITIONS ACROSS NRN
INDIANA LATER TODAY. THERE IS HWVR STILL CONSIDERABLE UNCERTAINTY
ON TIMING AND EVEN OCCURRENCE OF DEEP CONVECTION OVER NRN INDIANA
THIS AFTN AS CLOUD COVER COULD DELAY OR PREVENT SGFNT
DESTABILIZATION. A SECOND CDFNT WILL APPROACH THE AREA FROM THE
NORTH LATE TONIGHT AND SHOULD RESULT IN LOWERING CIGS/VSBYS BY
DAWN THU.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...GALE WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY EVENING FOR
     LMZ043-046.

&&

$$

SYNOPSIS...JT
SHORT TERM...JT
LONG TERM...SKIPPER
AVIATION...JT


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