Area Forecast Discussion
Issued by NWS Northern Indiana

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000
FXUS63 KIWX 242344
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
744 PM EDT FRI JUL 24 2015

.SYNOPSIS...
ISSUED AT 321 AM EDT FRI JUL 24 2015

HIGH PRESSURE WILL CONTINUE TO PROVIDE DRY WEATHER AND SEASONABLE
TEMPERATURES TODAY AND TONIGHT. THIS HIGH WILL SHIFT OFF TO THE
EAST FOR SATURDAY AS AN UPPER LEVEL DISTURBANCE APPROACHES THE
GREAT LAKES REGION. THIS WILL RESULT IN A CHANCE OF SHOWERS AND
THUNDERSTORMS SATURDAY AND SATURDAY NIGHT. A CHANCE OF SHOWERS AND
THUNDERSTORMS MAY LINGER INTO SUNDAY...ESPECIALLY ACROSS PORTIONS
OF NORTHWEST AND WEST CENTRAL INDIANA. HIGH TEMPERATURES THIS
AFTERNOON WILL REACH INTO THE MID 80S...WITH LOW TEMPERATURES
TONIGHT DROPPING BACK INTO THE MID 60S.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 254 PM EDT FRI JUL 24 2015

LATEST SURFACE ANALYSIS STILL HAS HIGH PRESSURE THAT HAS PROVIDED
SUCH PLEASANT WEATHER OVER THE PAST FEW DAYS CENTERED OVER THE
REGION. ONGOING MCS IN THE MID MS VALLEY THAT DEVELOPED AHEAD OF A
QUASI-STATIONARY FRONTAL BOUNDARY NOW TAKING A SOUTHERLY DIVE DOWN
THE EASTERN EDGE OF THICKNESS RIDGE THROUGH IOWA AND TOWARD MISSOURI
THIS AFTERNOON. FRONTAL WAVE FORMING ALONG BOUNDARY IN THE CENTRAL
PLAINS EXPECTED TO BE FOCUS FOR NOCTURNAL CONVECTION TONIGHT WHILE
LOW PRESSURE CENTERED OVER NORTHERN ONTARIO AND SHORT WAVE ENERGY
ENTERING NW GREAT LAKES REGION WILL KEEP LARGE SCALE FORCING AND
ASSOCIATED PRECIP NORTH OF OUR AREA. FRONTAL BOUNDARY WILL APPROACH
THE AREA ON SATURDAY WITH AN INCREASINGLY UNSTABLE AIRMASS OUT AHEAD
OF IT AS CAPES EXPECTED TO APPROACH 2500-3000J/KG BY LATE SATURDAY
AFTN OVER THE AREA. HOWEVER...LARGE SCALE FORCING ABSENT AS WEAK
MASS CONVERGENCE ALONG SURFACE BOUNDARY AND EFFECTIVE BULK SHEAR
AROUND 30KTS WILL LIMIT CONVECTIVE DEVELOPMENT IN BOTH CHANCE AND
AREAL EXTENT. THIS IS REFLECTED IN SLIGHT/CHANCE POPS IN GRIDS AND
WILL CONTINUE THIS TREND. CONTINUED INCREASE IN HUMIDITY IN SW FLOW
AHEAD OF APPROACHING FRONT WILL HAVE DEWPOINTS APPROACHING 70F IN
THE SOUTHERN CWA SATURDAY AFTERNOON...THIS WILL CONTINUE UPWARD
TREND IN LOWS WITH MID-UPPER 60S TONIGHT. ADDL CLOUD COVER EXPECTED
ON SATURDAY WILL MAINTAIN HIGHS IN THE MID 80S.


&&

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 254 PM EDT FRI JUL 24 2015

DRIER/MORE STABLE POST-FRONTAL AIR WILL BUILD INTO AT LEAST
NORTHERN/EASTERN PORTIONS OF THE FORECAST AREA UNDER MID LEVEL
NORTHWEST FLOW SATURDAY NIGHT INTO SUNDAY. LATEST GUIDANCE ALSO MORE
AGGRESSIVE IN DRYING REACHING AREAS SOUTHWEST OF HIGHWAY 30...THOUGH
HELD ONTO LOW POPS HERE GIVEN CLOSE PROXIMITY TO STALLED THETA-
E/INSTABILITY GRADIENT.

HUMIDITY/TEMPS WILL BE ON THE INCREASE MONDAY THROUGH WEDNESDAY AS
MID LEVEL HEIGHTS BUILD AND LOW LEVEL THETA-E RIDGE SHIFTS INTO THE
AREA ON THE NORTHEAST FRINGE OF AN EXPANDING SOUTH-CENTRAL
CONUS UPPER RIDGE. HIGH TEMPS BY TUESDAY COULD REACH NEAR 90F WITH
HEAT INDICES PUSHING 100F...ALTHOUGH THIS IS LOW CONFIDENCE GIVEN
POTENTIAL FOR A REMNANT MCS TO DROP THROUGH ON RIDGE PERIPHERY
MONDAY AND TUESDAY. AS A RESULT REMAINED SOMEWHAT CONSERVATIVE
REGARDING HIGHS AND RETAINED LOW POPS LATER SUNDAY NIGHT THROUGH
TUESDAY GIVEN RING OF FIRE CONCERNS.

NEXT/STRONGER LARGE SCALE UPPER TROUGH STILL ON TRACK TO FLATTEN THE
AFOREMENTIONED RIDGE AND DRIVE A SEASONABLY STRONG COLD FRONT THROUGH
THE LOCAL AREA LATER WEDNESDAY/EARLY THURSDAY PER LAST SEVERAL MODEL
CYCLES. A ROUND OF CONVECTION WILL LIKELY ACCOMPANY THIS FEATURE BUT
TIMING/COVERAGE/INTENSITY AT THIS FCST RANGE REMAINS UNCERTAIN.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 739 PM EDT FRI JUL 24 2015

EXPECT VFR CONDITIONS OVERNIGHT WITH SOME HIGH LEVEL CLOUDS
IMPACTING THE TAF SITES POSSIBLY. MVFR CIGS ARE EXPECTED SAT
MORNING AHEAD OF A FRONTAL BOUNDARY. WITH SOME INSTABILITY PRESENT
AHERAD OF THE BOUDNARY...ISOLATED CONVECTION MAY DEVELOP BUT
OPTED TO NOT INCLUDE AT TAF SITES. EXPECT A WINDSHIFT AT KSBN IN
THE 18-20Z TIME FRAME WITH WINDS TURNING WEST AT KFWA AROUND
19-21Z.

&&

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

$$

SYNOPSIS...MARSILI
SHORT TERM...LOGSDON
LONG TERM...STEINWEDEL
AVIATION...MF


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