Area Forecast Discussion
Issued by NWS Northern Indiana

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000
FXUS63 KIWX 181705
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
1205 PM EST TUE NOV 18 2014

.SYNOPSIS...
ISSUED AT 1150 AM EST TUE NOV 18 2014

LAKE EFFECT SNOW WILL CONTINUE TODAY FOR FAR NORTHERN INDIANA AND
SOUTHWESTERN MICHIGAN. THIS WILL SHIFT TO JUST THE MICHIGAN
COUNTIES LATER TODAY INTO TONIGHT AS THE WIND TURNS TO A MORE
SOUTHWESTERLY DIRECTION. HIGH TEMPERATURES TODAY WILL BE IN THE
TEENS FOR MOST OF THE REGION WITH AROUND 20 NEAR THE OHIO RIVER.
LOWS TONIGHT WILL RANGE FROM AROUND 10 DEGREES IN THE NORTH TO THE
MIDDLE TEENS NEAR THE OHIO RIVER. WIND CHILL VALUES WILL BE IN THE
SINGLE DIGITS TODAY AND RANGE FROM MINUS 3 TO 6 TONIGHT.

&&

.UPDATE...
ISSUED AT 938 AM EST TUE NOV 18 2014

UPDATED ZONES AND GRIDS TO SHIFT HEAVIEST BANDS A BIT FURTHER
NORTH BASED ON RADAR TRENDS AND SFC FLOW.

HEAVIEST SNOW BANDS HAVE SHIFTED INTO BERRIEN AND CASS COUNTIES
WITH A NARROW BAND OF SOMEWHAT LIGHTER SNOW OCCURRING VICINITY OF
MICHIGAN CITY. POINTS EAST OF HERE WERE SEEING SCATTERED SNOW
SHOWERS WITH LOCATIONS BETWEEN THE TOLL ROAD AND DOWN TO ROUGHLY
US 24 IN INDIANA SEEING FLURRIES/LGT SNOW SHOWERS. THIS WAS ALL
COURTESY OF A WEAK DISTURBANCE MOVING THROUGH THE AREA. WILL NEED
TO WATCH ALONG/NORTH OF THE TOLL ROAD INTO EARLY AFTERNOON AS SOME
INDICATIONS UPSTREAM OF FLOW BECOMING MORE WESTERLY AGAIN FOR A
PERIOD. GIVEN CLEANUP STILL UNDERWAY AND RISK OF ADDITIONAL SNOW
SHOWERS...WILL LEAVE WARNING ALONG FOR LA PORTE...ST JOE AND
ELKHART COUNTIES IN INDIANA FOR THE TIME BEING. ADDED MENTION OF
LGT SNOW SHOWERS FURTHER SOUTH GIVEN VISIBILITIES DROPPING INTO
THE 3 TO 5 MILE RANGE...BIT MORE THAN FLURRIES. NO ACCUMS
EXPECTED.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 428 AM EST TUE NOV 18 2014

BUSY SHORT TERM THIS MORNING WITH IMPRESSIVE ONGOING LAKE EFFECT
SNOW EVENT. AS FEARED AND MENTIONED IN PREVIOUS
DISCUSSIONS...SOUTHERN EXTENT OF LAKE BANDS DID MAKE IT SOUTH OF
THE MICHIGAN STATE LINE...A RARE OCCURRENCE FOR THESE WESTERLY
FLOW EVENTS. RUC13 AND OTHER HIRES GUIDANCE SHOWED A SLIGHT
VEERING TO THE 925-850MB WINDS ALONG WITH SURFACE THERMAL INDUCED
CONVERGENCE WHICH ALLOWED SOUTHERN MOST BAND TO BECOME STRONGER.
THIS BAND HAS PERSISTED NON STOP SINCE ABOUT 9 PM LAST NIGHT. HI
RES GUIDANCE LOCKED ONTO LOW LEVEL FLOW AND ONLY SHOWING A SLIGHT
BACKING THROUGH MID MORNING DESPITE A COUPLE WEAK SHORT WAVES.
THIS GUIDANCE COMBINED WITH REPORTS THROUGH 1 AM OF BETWEEN 2 AND
4 INCHES OF SNOW PROMPTED THE OVERNIGHT UPGRADE TO A WARNING.
BLOWING AND DRIFTING ALSO LEADING TO NUMEROUS ACCIDENTS AND ISSUES
AND EXPECT MORE PROBLEMS AS MORNING TRAFFIC INCREASES.

THE HIRES ARW EAST HAD A GOOD HANDLE ON THIS SOUTHERN BAND AND
GENERALLY FOLLOWED IT WITH A BLEND OF RUC AND LOCAL WRF TO TWEAK
SNOW FORECASTS. SATELLITE SHOWS A RATHER STRONG SHORT WAVE OVER WI
HEADING SOUTH AND MODELS SEEM LOCKED ONTO THIS FEATURE...CROSSING
SOUTHERN LAKE MICHIGAN THIS MORNING FOLLOWED BY INCREASING
SUBSIDENCE AND BACKING LOW LEVEL FLOW. EXPECT BANDS TO PERSIST
WITH ONLY MINOR FLUCTUATIONS THROUGH MID MORNING...SIMILAR TO WHAT
WE HAVE SEEN OVERNIGHT. THIS WILL LEAD TO ADDITIONAL SNOWFALL
RATES OF BETWEEN ONE HALF AND ONE INCH PER HOUR. GREATEST SNOWFALL
AMOUNTS EARLY THIS MORNING HAVE BEEN OVER CENTRAL CASS COUNTY WITH
LAST REPORTS OF 10 INCHES AROUND CASSOPOLIS SEVERAL HOURS AGO.
STILL EXPECT ISOLATED AMOUNTS IN CASSOPOLIS AREA TO BE CLOSER TO
15 TO 18 INCHES BY THE TIME EVENT ENDS. REMAINDER OF AREA WILL
VARY WITH AMOUNTS AS USUAL FOR LAKE EFFECT WITH 4 TO 8 LIKELY NEAR
TOLL ROAD AND 8 TO 12 IN MICHIGAN. COUNTING ON COMBINATION OF
SHORT WAVE AND DIURNAL TIMING TO CREATE MORE OF A CELLULAR NATURE
TO BANDS LATER THIS MORNING AND AID IN REDUCING INTENSITY A BIT
THROUGH THE DAY AS FLOW BACKS. STRONG WEST WINDS OF 15 TO 25 TODAY
WILL CREATE HAVOC ON ROADS AND NEAR WHITEOUT CONDITIONS IN
STRONGER BANDS.

BASED ON 00Z FCST SOUNDINGS FROM ARW AND NAM DID INCREASE POPS FROM
00-06Z TONIGHT OVER BERRIEN AND CASS COUNTIES AS SOUTHWEST FLOW
PERSISTS WITH SATURATED BUT SHRINKING DGZ. ACCUMS SHOULD BE FALLING
OFF BUT STILL MAY SEE SOME LIGHT ACCUMS.

REMAINDER OF AREA TO SEE CLOUDS INCREASE TODAY SIMILAR TO YESTERDAY
WITH SHORT WAVE PASSING THROUGH. SOME FLURRIES POSSIBLE ONCE AGAIN.
RECORD LOW MAX TEMPERATURES TODAY MOST AREAS...ACTUALLY SHATTERING
RECORDS BY SEVERAL DEGREES. ALREADY BROKE THE RECORD LOW FOR TODAY
AT KFWA DESPITE WIND. WIND CHILLS STILL FROM ZERO TO 10 BELOW THIS
MORNING. TONIGHT...LOWS LIKELY TO OCCUR EARLY WITH TEMPS STEADY OR RISING
AS CLOUD COVER INCREASES AHEAD OF NEXT SHORT WAVE.

&&

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 428 AM EST TUE NOV 18 2014

ANOTHER BOUT WITH POSSIBILITY OF SYSTEM SNOW IS EXPECTED
WEDNESDAY FOLLOWED BY LAKE EFFECT SNOW WEDNESDAY NIGHT THROUGH AT
LEAST THURSDAY NIGHT. THE 12KM NAM PER 285K ISENTROPIC CHART STILL
SUPPORTS UP TO AN INCH OF SNOW ACCUMULATION PER GARCIA/MIXING
RATIO METHOD. CONCERN FOR INCOMPLETE SATURATION OF THE CLOUD LAYER
WILL LIMIT SNOWFALL. HOWEVER...GOOD LIFT IS INDICATED WITH OVER 2
G/KG OF MOISTURE. HAVE RAMPED UP LAKE EFFECT SNOW CHANCES
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT AS ARCTIC AIR SPREADS BACK
OVER THE AREA. SFC/700 MB DELTA T VALUES BECOME SUBSTANTIAL AGAIN
AROUND 30C. EVEN WITH A LIMITED FETCH...EXPECT SNOW SHOWERS TO
INCREASE WEDNESDAY NIGHT AND PERSIST INTO THURSDAY AS DELTA T
VALUES INCREASE AND WINDS VEER A LITTLE MORE TO THE NORTHWEST.

FOR THE REST OF THE PERIOD...MUCH WARMER AIR WILL RETURN TO THE AREA
THIS WEEKEND. A RAIN/SNOW MIX IS POSSIBLE SATURDAY...BUT
PRECIPITATION SHOULD BECOME ALL RAIN BY SATURDAY NIGHT  AS THERMAL
PROFILES INDICATED LIQUID PRECIPITATION.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1236 AM EST TUE NOV 18 2014

925-850MB WINDS HAVE VEERED TO A MORE NORTHWEST ORIENTATION LAST
COUPLE HOURS AND THIS HAS ALLOWED A DOMINATE SOUTHERN BAND OF LAKE
EFFECT SNOW TO MOVE INTO KSBN. RADAR TRENDS SHOW A RATHER
STATIONARY BAND AND LATEST HIRES GUIDANCE SUGGEST THIS BAND MAY
NOT MOVE MUCH OVERNIGHT AS FLOW REMAINS 925-850MB FLOW REMAINS
WEST NORTHWEST UNTIL MID MORNING. THUS HAVE PREVAILING IFR
CONDITIONS WITH LIFR POSSIBLE AT TIMES INTO THE MID MORNING. FLOW
THEN BACKS SOUTHWEST AND SNOW SHOULD SHIFT OUT OF KSBN. KFWA
CURRENTLY VFR BUT SATELLITE SHOWS SOME BROKEN MVFR CLOUDS IN
NORTHERN INDIANA HEADING EAST SO MAY SEE BRIEF PERIODS OF MVFR
THROUGH THE NIGHT.


&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...WINTER STORM WARNING UNTIL 7 PM EST /6 PM CST/ THIS EVENING FOR
     INZ003>005.

MI...WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR MIZ077>079.

     WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ080.

OH...NONE.
LM...GALE WARNING UNTIL 4 PM EST THIS AFTERNOON FOR LMZ043-046.

&&

$$

UPDATE...FISHER
SYNOPSIS...LOTHAMER
SHORT TERM...LASHLEY
LONG TERM...SKIPPER
AVIATION...LASHLEY


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