Area Forecast Discussion
Issued by NWS Northern Indiana

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000
FXUS63 KIWX 312331
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
731 PM EDT FRI OCT 31 2014

.SYNOPSIS...
ISSUED AT 400 PM EDT FRI OCT 31 2014

A STRONG STORM SYSTEM WILL GRADUALLY SINK SOUTHWARD TO THE OHIO
RIVER VALLY TONIGHT. SCATTERED TO NUMEROUS RAIN AND SNOW SHOWERS
SHOULD GRADUALLY BECOME ALL SNOW THIS EVENING. HOWEVER...ANY SNOW
ACCUMULATIONS ARE EXPECTED TO REMAIN LIGHT AND MAINLY ACROSS
GRASSY AREAS. WINDS WILL GRADUALLY DIMINISH TONIGHT AS THE STORM
SYSTEM EXITS THE AREA. A RIDGE OF HIGH PRESSURE WILL APPROACH THE
REGION THIS WEEKEND...RESULTING IN CONTINUED MUCH BELOW NORMAL
TEMPERATURES.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 414 PM EDT FRI OCT 31 2014

STRONG WINDS AND RAIN/SNOW SHOWERS TO BEGIN THE SHORT TERM PERIOD
WILL BE FOLLOWED BY TRANSITION TO QUIETER WEATHER FOR SATURDAY.

UPPER LEVEL LOW CENTERED ACROSS NORTHERN INDIANA WILL CONTINUE TO
SLIP SOUTHWARD TO THE OHIO RIVER VALLEY TONIGHT. SHARP LOW LEVEL
TROUGH ACCOMPANYING THIS SYSTEM WILL OVERSPREAD SOUTHEAST HALF OF
THE AREA OVER THE NEXT SEVERAL HOURS. PASSAGE OF THIS TROUGH
RESULTED IN SOME 60+ MPH WIND GUSTS FOR A FEW MARINE LOCATIONS
EARLIER TODAY AND WIND GUSTS IN THE 50 MPH TO 60 MPH WILL BE
POSSIBLE THROUGH LATE THIS AFTERNOON CLOSER TO THE LAKE MICHIGAN
SHORELINE. DID ISSUE A HIGH WIND WARNING FOR BERRIEN AND LA PORTE
COUNTIES EARLIER THIS AFTERNOON...AND WILL LET THIS CONTINUE WITH
THE AFTERNOON PACKAGE. THE WIND ADVISORY HEADLINES IN EFFECT THROUGH
00Z WILL ALSO REMAIN INTACT WITH NO CHANGE ANTICIPATED.

LOW LEVEL THERMAL TROUGH WILL CONTINUE TO OVERSPREAD THE REGION
THROUGH EARLY EVENING AIDING IN TRANSITION TO MAINLY SNOW SHOWERS BY
00Z. AREAS DOWNWIND OF LAKE MICHIGAN ACROSS EXTREME NORTHWEST
INDIANA MAY BE THE LAST AREA TO SWITCH OVER TO ALL SNOW
SHOWERS...ALTHOUGH BY THIS TIME MORE VEERED LOW LEVEL FLOW MAY BEGIN
TO TAKE LAKE EFFECT/ENHANCED FOCUS JUST TO THE WEST OF THE FORECAST
AREA. ACROSS REMAINDER OF THE AREA...ELONGATED SYNOPTIC VORT MAX
ACROSS NORTHWEST INDIANA/SOUTHWEST LOWER MICHIGAN WILL GRADUALLY
SHIFT SOUTHEAST AND BECOME INCREASINGLY INFLUENCED BY MID/UPPER
LEVEL DEFORMATION. THIS SHOULD WEAKEN THE MID/UPPER LEVEL FORCING AS
THE UPPER PV ANOMALY SHIFTS INTO EASTERN PORTIONS OF THE AREA
TONIGHT. HOWEVER...WITH TROWAL-LIKE FEATURE AND SOUTHWARD DIGGING
OF UPPER WAVE PROMOTING PROLONGED FORCING...WILL GO AHEAD AND ADD
SOME LIGHT SNOW ACCUMULATIONS OF A FEW TENTHS ACROSS EASTERN HALF
OF THE AREA ALSO. ANY LIGHT SNOW ACCUMULATIONS SHOULD OCCUR MAINLY
ON GRASSY AREAS.

LATER THIS EVENING...MORE OF A PURE LAKE EFFECT SHOULD CONTINUE TO
AFFECT AREAS ESPECIALLY WEST OF THE FORECAST AREA WHILE WILL
MAINTAIN SCATTERED SNOW SHOWERS ACROSS THE FAR EAST OVERNIGHT DUE
TO DIGGING NATURE OF AFOREMENTIONED WAVE. A FEW SNOW FLURRIES MAY
PERSIST ACROSS THE FAR EAST EARLY SATURDAY...WITH DIMINISHING
CLOUDS EXPECTED IN THE AFTERNOON. HOWEVER...IT IS POSSIBLE THAT
EASTERN AREAS MAY BE A BIT SLOW TO CLEAR SATURDAY AFTERNOON.
UNSEASONABLY COOL CONDITIONS TO PERSIST SATURDAY DUE TO LOW LEVEL
THERMAL TROUGH REMAINING ANCHORED ACROSS THE AREA...SUPPORTING
HIGHS FROM THE UPPER 30S TO LOWER 40S.

&&

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 414 PM EDT FRI OCT 31 2014

UPR PATTN ACRS NOAM IN A STATE OF EXTREME FLUX THIS PD AS INITIAL
DEEP TROUGH DVLPG ALG THE EAST COAST LIFTS OUT THROUGH THE CANADIAN
MARITIMES. WHAT FOLLOWS EARLY ON THIS PD IS A RELAXATION INTO
LARGELY ZONAL FLW ACRS THE CONUS. HWVR FULL GAMUT OF 12Z GUIDANCE
HAS SHIFTED GEARS SIGLY W/SECONDARY SHARP TROUGH AMPLIFICATION ACRS
THE ERN LAKES/NEW ENGLAND LT PD.

REGARDLESS EARLY PD WILL SEE SIG TEMP MODERATION AS SHRT AMPLITUDE
RIDGING BLDS BACK IN BY MON. FAIRLY STOUT LL THERMAL RIDGE WITHIN
INCREASING SWRLY FLW WILL PUSH TEMPS BACK TO JUST ABV NORMAL AND
WILL WARM PRIOR TEMPS A BIT MORE IN LIGHT OF AT LEAST 10C H85 TEMPS.
PRIMARY WX MAKER WILL BE NEW SW WRAPPING UP OFF COAST OF NRN CA
WHICH WILL GRAVITATE INLAND FRI NIGHT. PART OF THIS WILL BREAKOUT
NEWD INTO SRN CANADA BY MON AND PROPEL ANOTHER CDFNT EWD INTO THE
WRN LAKES/OH VALLEY BY TUE. GIVEN ROBUST LL MSTR RTN AND FNTL
DYNAMICS WILL CONT GENERAL LIKELY POPS IN THE TUE TIME FRAME. HWVR
IN CONTEXT OF MODEL IMPLIED SECONDARY DEEP TROUGH AMPLIFICATION ACRS
THE ERN US TWD FRI...WILL MAKE SUBSTANTIAL CHGS IN LT PDS.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 726 PM EDT FRI OCT 31 2014

FORECAST GENERALLY REMAINS ON TRACK WITH SOME TWEAKS TO LATEST
TAF PACKAGE. PRECIPITATION HAS ENDED AT KSBN AND WILL END SHORTLY
AT KFWA. CIGS AT KSBN HAVE RISEN TO VFR WHILE MVFR STILL AT KFWA.
UPSTREAM OBS SUGGEST KSBN COULD SEE A FEW MVFR CIGS THIS EVENING
WITH NORTHERLY FLOW SO ALLOWED A TEMPO THERE. WILL BE A LONGER
PERIOD OF PREVAILING MVFR AT KFWA WITH EVENTUALY RISING CIGS LATE
TONIGHT. MODELS CONTINUE TO SHOW CLEARING DEVELOPING LATER THIS
EVENING OVER MICHIGAN AND MOVING SOUTH. REMAINED OPTIMISTIC WITH
TAFS GIVEN THESE TRENDS BUT HAVE YET TO SEE ANY HOLES OPEN UP WITH
LOWER STRATOCU STILL HOLDING FIRM. THIS CLEARING MAY NEED TO BE
ADJUSTED LATER WITH 06Z TAFS BUT WILL MONITOR. WINDS SHOULD
GRADUALLY DIMINISH THROUGH THE EVENING BUT STILL REMAIN ABOVE 10
TO 14 KNOTS SUSTAINED UNTIL VERY NEAR THE END OF THIS PERIOD.


&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...HIGH WIND WARNING UNTIL 10 PM CDT THIS EVENING FOR INZ003.

     LAKESHORE FLOOD ADVISORY UNTIL 4 AM CDT SATURDAY FOR INZ003.

     WIND ADVISORY UNTIL 8 PM EDT /7 PM CDT/ THIS EVENING FOR INZ004-
     005-012>015-020-022.

MI...HIGH WIND WARNING UNTIL 11 PM EDT THIS EVENING FOR MIZ077.

     LAKESHORE FLOOD ADVISORY UNTIL 5 AM EDT SATURDAY FOR MIZ077.

     WIND ADVISORY UNTIL 8 PM EDT THIS EVENING FOR MIZ078-079.

OH...NONE.
LM...STORM WARNING UNTIL 8 PM EDT THIS EVENING FOR LMZ043-046.

     GALE WARNING UNTIL 5 AM EDT SATURDAY FOR LMZ043-046.

&&

$$

SYNOPSIS...MARSILI
SHORT TERM...MARSILI
LONG TERM...T
AVIATION...LASHLEY


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