Area Forecast Discussion
Issued by NWS Northern Indiana

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000
FXUS63 KIWX 292327
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
727 PM EDT SAT AUG 29 2015

.SYNOPSIS...
ISSUED AT 359 PM EDT SAT AUG 29 2015

A WEAKENING TROUGH WILL CROSS OVER THE REGION TONIGHT AND SUNDAY.
SCATTERED TO NUMEROUS RAIN SHOWERS ARE EXPECTED OVERNIGHT...WITH
ISOLATED THUNDERSTORMS POSSIBLE IN THE EVENING. OTHERWISE...AREAS
OF FOG ARE POSSIBLE LATER TONIGHT AND SUNDAY MORNING. LOWS WILL
BE IN THE 60S. THERE IS AN ADDITIONAL CHANCE FOR SHOWERS AND
THUNDERSTORMS SUNDAY AFTERNOON. HIGHS WILL BE IN THE 70S AND LOW
80S ON SUNDAY...COOLEST NEAR LAKE MICHIGAN.

&&

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 359 PM EDT SAT AUG 29 2015

MAIN FOCUS OF THE SHORT TERM IS PRECIPITATION CHANCES TONIGHT AND
SUNDAY...WITH POTENTIAL FOR FOG DEVELOPMENT LATE TONIGHT.

THE UPPER LEVEL DIVERGENCE ASSOCIATED WITH A 300MB JET STREAK THAT
HELPED SUSTAIN PRECIPITATION IN THE NORTH/NORTHWEST EARLIER TODAY
WILL MOVE INTO OUR EASTERN/CENTRAL CWA THIS EVENING....THOUGH IT
WILL GRADUALLY WEAKEN IN INTENSITY. THE VORT MAX ASSOCIATED WITH THE
500MB TROUGH IS SITUATED OVER OUR NORTHWEST NOW...AND WILL GRADUALLY
SHIFT EASTWARD UNTIL IT DISSIPATES SUNDAY MORNING. DEEPEST MOISTURE
ALSO DIMINISHES GRADUALLY AS HIGH PRESSURE OVER THE ATLANTIC SHIFTS
SOUTHEAST AND THE LOW PRESSURE SYSTEM OVER IA SINKS SOUTHEASTWARD
OVERNIGHT. AN AXIS OF DEEPER MOISTURE PER PWATS OF 1.6-1.8 INCHES
AND 500-700MB RH COLLOCATED WITH BEST RADAR RETURNS THIS AFTERNOON
WILL SHIFT TOWARDS THE CENTRAL AND EASTERN PORTIONS OF THE CWA
TONIGHT. AS A RESULT...HAVE PRECIPITATION CHANCES SHIFTING EASTWARD
AND DIMINISHING THROUGH THE NIGHT AS BETTER FORCING/DEEPER MOISTURE
EXIT THE AREA. LOWS WILL BE IN THE 60S OVERNIGHT. WITH ABUNDANT
MOISTURE...RECENT/ONGOING RAINFALL...AND FAIRLY LIGHT WINDS EXPECTED
TONIGHT...ADDED IN PATCHY/AREAS OF FOG FOR LATE TONIGHT.

PRECIPITATION CHANCES CONTINUE FOR SUNDAY MORNING JUST PRIOR TO THE
DEPARTURE OF THE DIMINISHING 500MB TROUGH. EXPECT PATCHY/AREAS OF
FOG TO DIMINISH BY MID-LATE MORNING. A WEAK SHORTWAVE SLIDES THROUGH
TOWARDS THE AFTERNOON...BUT OTHERWISE THERE IS VERY LITTLE IN THE
WAY OF FORCING. DESPITE THIS...SOME MODELS SUGGEST SCATTERED
SHOWERS/STORMS DURING THE AFTERNOON...ESPECIALLY TO THE SOUTHEAST.
KEPT LOWER END-CHANCE/SLIGHT CHANCE POPS TO ACCOUNT FOR THIS...BUT
CONFIDENCE IS LOW. HIGHS SHOULD REACH INTO THE 70S AND LOW
80S...COOLEST NEAR LAKE MICHIGAN WHERE WINDS WILL GENERALLY BE OUT
OF THE NORTH-NORTHWEST.

&&

.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 359 PM EDT SAT AUG 29 2015

AN UPPER LEVEL SHEAR AXIS SITUATED OVER THE LOWER/MID MS VALLEY
WEAKENS SUN NIGHT THROUGH MON AS UPPER RIDGING BUILDS OVER THE OH
VALLEY. BY TUE AN UPPER SHORT WAVE LIFTS NEWD INTO THE GTLKS REGION
CAUSING THE RIDGE TO FLATTEN SOMEWHAT. ADDITIONAL WEAK WAVES ARE
EXPECTED TO LIFT NEWD TOWARD THE GTLKS REGION BRINGING A CHANCE FOR
SCATTERED SHRA/TSRA TUE/WED WITH AFTERNOON HEATING BEING THE MORE
PRONOUNCED PERIODS FOR PRECIP CHANCES. THU THE RIDGE AXIS REDEVELOPS
WEST OF INDIANA ALLOWING FOR IMPULSES TO DROP SEWD TOWARD THE LOWER
GTLKS. THIS WILL CONT AFTN PRECIP CHANCES WITH WEAK ASCENT PRESENT
THROUGH FRI. STRONG INSTABILITY ISN`T EXPECTED SO GENERAL AFTN
SCATTERED TSTMS AGAIN. THE PRESENCE OF CLOUDS AND SCATTERED PRECIP
SHOULD PRECLUDE TEMPS BREAKING 90 SO CONT MID TO UPPER 80S THROUGH
SAT.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 709 PM EDT SAT AUG 29 2015

INVERTED TROF FROM MO NEWD THROUGH NRN INDIANA WILL PERSIST
OVERNIGHT AND GRDLY WEAKEN. NUMEROUS SHRA AND ISOLATED TS OVER NRN
INDIANA SHOULD GRDLY DIMINISH OVERNIGHT AND SHIFT EAST AS WK UPR
TROF MOVES ACROSS THE AREA. MOIST LOW LEVELS WITH LIGHT BOUNDARY
LAYER WINDS SHOULD ALLOW SOME BR TO DVLP OVERNIGHT WITH MVFR/IFR
VSBYS... SLOWLY BURNING OFF LATER SUNDAY MORNING. ABUNDANT LOW
LEVEL MOISTURE WILL PERSIST SUNDAY ALLOWING A BKN CU DECK TO DVLP
WITH A FEW SHRA/TS PSBL IN THE AFTN ALONG LINGERING WK SFC
BOUNDARY. LEFT MENTION OF CONVECTION OUT OF TAFS AS LOCATION OF
BOUNDARY AND AMOUNT OF DIURNAL INSTABILITY QUESTIONABLE ATTM.

&&

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

$$

SYNOPSIS...MCD
SHORT TERM...MCD
LONG TERM...FRAZIER
AVIATION...JT


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