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000
FXUS63 KIWX 011710
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
110 PM EDT FRI AUG 1 2014

.SYNOPSIS...
ISSUED AT 329 AM EDT THU AUG 1 2014

SCATTERED...MAINLY AFTERNOON AND EARLY EVENING...SHOWERS WILL BE
POSSIBLE TODAY AND SATURDAY AS AN UPPER LEVEL TROUGH TRACKS INTO
THE REGION. HIGHS EACH DAY WILL REACH TO NEAR 80 DEGREES. DRY
CONDITIONS ARE EXPECTED ON SUNDAY AS THE UPPER LEVEL SYSTEM
MOVES OFF TO THE EAST.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 329 AM EDT FRI AUG 1 2014

SHORTWAVE TROUGH ACROSS IOWA AS OF 07Z WILL SHARPEN EASTWARD INTO
THE REGION LATER TODAY INTO TONIGHT. SOME SUBTLE MOISTURE
ADVECTION...ESPECIALLY NEAR 850 MB WHERE DEWPOINTS WILL INCREASE
TO 10-12C...AND STEEPENING SFC-700 MB LAPSE RATES IN TANDEM WITH
DAYTIME HEATING UNDER A BROAD MID/UPPER TROUGH AXIS (500 MB TEMPS
-15C)...SHOULD ALLOW SCATTERED SHOWERS/STORMS TO FIRE THIS
AFTERNOON. BEST CHANCES PER HI RES GUIDANCE WILL BE INTO NW
INDIANA LATE THIS MORNING/EARLY AFTERNOON...AND POINTS EAST MID-
LATE AFTERNOON. LACKING FLOW/SHEAR, MODERATE MLCAPE TO NEAR 1500
J/KG, AND WET BULB ZERO HEIGHTS LESS THAN 10 KFT SUGGESTS A LOW
PULSE HAIL/WIND THREAT AT BEST THIS AFTN. PRECIP COVERAGE/CHANCES
WILL DIMINISH WITH TIME THIS EVENING INTO THE EARLY OVERNIGHT AS
INSTABILITY SLOWLY WANES.

&&

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 329 AM EDT FRI AUG 1 2014

PERIOD WILL BEGIN SATURDAY WITH MID LEVEL TROUGH AXIS OVER THE AREA
AND SLOWLY SHIFTING EAST. ENOUGH MODEST INSTABILITY AND POTENTIAL
WEAK SHORT WAVES TO CONTINUE WITH LOW CHANCE POPS DURING THE DAY
WITH HIGHEST CHANCES EAST. NEGATIVE VORTICITY ADVECTION AND
SUBSIDENCE SUNDAY WITH RISING HEIGHTS IN WAKE OF TROUGH DEPARTURE
SHOULD LEAD TO DRY CONDITIONS WITH TEMPS RISING TO AROUND 80 OR THE
LOWER 80S.

NORTHWEST FLOW ALOFT WILL PERSIST NEXT WEEK WITH WEAK FRONTAL
BOUNDARY SAGGING INTO THE AREA BY TUESDAY. GIVEN RECENT PATTERN WILL
ALLOW LOW POPS TO CONTINUE TUESDAY AND WEDNESDAY WITH THIS
BOUNDARY...MODEST INSTABILITY AND WEAK EMBEDDED SHORT WAVES. BETTER
CHANCES FOR THUNDERSTORMS STILL EXIST LATE IN THE WEEK WITH APPROACH
OF SHARPER MID LEVEL TROUGH AND DECENT SURFACE REFLECTION. OBVIOUS
DIFFERENCES AMONG MEDIUM RANGE MODELS WITH THIS SYSTEM AND WARM
FRONT MOVEMENT. MID CHANCE POPS LOOK REASONABLE WITH TIMING
UNCERTAINTY AND CONVECTIVE COVERAGE.

TEMPERATURES NEXT WEEK WILL BE TRICKY WITH WAVERING FRONTAL BOUNDARY
AND WARM SURGE SOUTH OF DEVELOPING WARM FRONT LATE IN WEEK. STAYED
CLOSE TO GIVEN BLENDED TEMPERATURES WITH HIGHS AROUND 80 TO LOWER
80S AND LOWS GENERALLY IN THE 60S NEXT WEEK.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 103 PM EDT FRI AUG 1 2014

SCT TSTMS DEVELOPING OVER THE AREA EARLY THIS AFTN AS CONVECTIVE
TEMPS IN THE M-U70S REACHED AHEAD OF APCHG WK SHRTWV. CONVECTION
MOST WIDESPREAD IN DIFFERENTIAL HEATING ZONE SOUTH OF LM AND THESE
SHOULD IMPACT SBN TERMINAL WITH MVFR OR PSBLY IFR CONDITIONS IN TSRA
EARLY IN THE PERIOD. GIVEN WK SHEAR/PULSE NATURE TO STORMS... CONTD
WITH JUST VCTS THIS AFTN AT FWA BUT WILL MONITOR AND MAY NEED TO
INCLUDE A TEMPO TSRA THERE AS WELL. CONVECTION EXPECTED TO
DIMINISH WITH LOSS OF HEATING THIS EVENING. SOME CLEARING LIKELY
ESPECIALLY AT SBN AS UPR LEVEL TROF AXIS MOVES TO NE INDIANA. THIS
SHOULD ALLOW BR TO DEVELOP WITH VSBYS LOWERING TO MVFR AT THE
TERMINALS BY MORNING.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&

$$

SYNOPSIS...STEINWEDEL
SHORT TERM...STEINWEDEL
LONG TERM...LASHLEY
AVIATION...JT


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