311 
FXUS63 KIND 202016
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
316 PM EST TUE JAN 20 2015 

.UPDATE...

THE AVIATION SECTION HAS BEEN UPDATED BELOW.

&&

.SYNOPSIS...
ISSUED AT 303 PM EST TUE JAN 20 2015 
A COUPLE OF UPPER SYSTEMS WILL BRING CHANCES FOR PRECIPITATION 
THROUGH WEDNESDAY NIGHT. HIGH PRESSURE WILL THEN KEEP CONDITIONS DRY 
THROUGH THE FIRST HALF OF THE WEEKEND. A SYSTEM COULD BRING MORE 
PRECIPITATION SUNDAY AND MONDAY. TEMPERATURES WILL GENERALLY REMAIN 
NEAR TO ABOVE AVERAGE.

&&

.NEAR TERM.../REST OF THIS AFTERNOON AND TONIGHT/
ISSUED AT 303 PM EST TUE JAN 20 2015 

CLOUDS WILL CONTINUE TO INCREASE ACROSS CENTRAL INDIANA THIS 
AFTERNOON. THESE WILL BE FROM THE APPROACHING COLD AIR ALOFT FROM 
THE NORTHWEST ALONG WITH HIGHER CLOUDS FROM AN UPPER SYSTEM PASSING 
THROUGH TO THE SOUTH.

COLD AIR WILL CONTINUE TO FLOW IN ALOFT TONIGHT...AND AN UPPER 
IMPULSE WILL PROVIDE SOME WEAK LIFT. MOISTURE IS PRETTY LIMITED 
TONIGHT. WILL CONFINE POPS TO THE NORTHERN HALF OF THE FORECAST AREA 
WHERE FORCING IS BEST...BUT WILL ONLY GO WITH SLIGHT CHANCE TO LOW 
CHANCE CATEGORY POPS.

BOUNDARY LAYER TEMPERATURES WILL BE WARM ENOUGH THIS EVENING TO GO 
WITH A MIX OF RAIN AND SNOW...BUT OVERNIGHT THEY SHOULD COOL ENOUGH 
TO GO WITH JUST SNOW. WILL HAVE TO KEEP ANY EYE ON THINGS THOUGH AS 
THERE ARE HINTS THAT MOISTURE MAY NOT BE DEEP ENOUGH TO INTRODUCE 
ICE INTO THE CLOUD. IF THIS IS THE CASE PRECIPITATION MAY BE DRIZZLE 
/OR FREEZING DRIZZLE IN SPOTS LATE TONIGHT/.

MAV MOS LOOKS A BIT TOO COOL GIVEN EXPECTED CLOUD COVER. WENT A 
LITTLE HIGHER.

&&

.SHORT TERM.../WEDNESDAY THROUGH FRIDAY/
ISSUED AT 303 PM EST TUE JAN 20 2015 

FOCUS IS ON PRECIPITATION CHANCES EARLY IN THE PERIOD. MODELS ARE 
CLOSE ENOUGH THAT A BLEND WAS USED.

ON WEDNESDAY A LITTLE STRONGER UPPER SYSTEM MOVES IN ALONG WITH A 
STRONGER UPPER JET. IN ADDITION A SURFACE TROUGH REMAINS NEAR THE 
AREA. THUS FEEL THAT CHANCES FOR PRECIPITATION WILL BE A LITTLE 
HIGHER. 

WENT CHANCE POPS ACROSS THE NORTHEAST HALF OF THE AREA WITH SLIGHT 
CHANCE POPS EXTENDING ACROSS PARTS OF THE SOUTHWEST. WENT DRY FAR 
SOUTHWEST BASED ON EXPECTED PLACEMENT OF THE FORCING. AS FAR AS 
PRECIPITATION TYPE...LOOKS COLD ENOUGH IN THE MORNING FOR JUST 
SNOW...BUT THE BOUNDARY LAYER SHOULD WARM ENOUGH DURING THE 
AFTERNOON TO GO A MIX OF RAIN AND SNOW NORTH TO JUST RAIN SOUTH.

MAV MOS MAY BE A BIT WARM WITH HIGHS WEDNESDAY WITH CLOUDS AND SOME 
COLD ADVECTION. WENT NEAR OR COOLER THAN MAV.

CONTINUED SOME LINGERING SLIGHT CHANCE POPS IN THE NORTH HALF 
WEDNESDAY NIGHT WITH WEAKENING SURFACE TROUGH IN PLACE. FOR THURSDAY 
INTO FRIDAY...HIGH PRESSURE WORKS INTO THE AREA. THIS SHOULD KEEP 
CONDITIONS DRY. 

ON THURSDAY WENT PESSIMISTIC ON CLOUDS...BUT ON FRIDAY THERE SHOULD 
BE ENOUGH SUBSIDENCE/DRYING FOR CLOUDS TO BREAK UP. 

GENERALLY STAYED WITH A MODEL BLEND FOR TEMPERATURES WEDNESDAY NIGHT 
THROUGH FRIDAY.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
ISSUED AT 153 PM EST TUE JAN 20 2015

ECMWF AND GFS BOTH AGREE ON THE OVERALL PATTERN THIS RUN. UPPER
PATTERN SUGGESTS A BROAD AND DEEP TROUGH DEVELOPING ACROSS THE
EASTERN PARTS OF THE UNITED STATES THROUGH THE
PERIOD...HOWEVER...MUCH OF THE COLDEST AIR APPEARS TO BE LOCKED TO
THE NORTHEAST OF INDIANA...OVER THE GREAT LAKES AND NEW ENGLAND.
THUS WITH COOL AND DRY CONTINENTAL FLOW...DRY WEATHER WILL BE
EXPECTED ON FRIDAY NIGHT AND SATURDAY.

GFS AND ECMWF BOTH SUGGEST A QUICK MOVING CLIPPER SYSTEM SWEEPING
OUT OF THE UPPER MIDWEST TO THE TENNESSEE RIVER VALLEY ON SUNDAY
AND MONDAY. WITH GOOD FORCING ASSOCIATED WITH THIS SYSTEM...WILL
INCLUDE POPS AT THAT TIME. DRY WEATHER IS EXPECTED TO RETURN
TUESDAY AS THE FORCING WITH THE PASSING CLIPPER DEPARTS AND DRY
AIR RETURNS.

&&

.AVIATION /DISCUSSION FOR THE 20/21Z TAF UPDATE/...
ISSUED AT 316 PM EST TUE JAN 20 2015

ONLY COSMETIC CHANGES REQUIRED TO TAF AT IND. PREVIOUS DISCUSSION 
FOLLOWS.

ISSUED AT 1228 PM EST TUE JAN 20 2015

MVFR AND IFR CEILINGS DEVELOPING BY LATE DAY AND CONTINUING INTO
WEDNESDAY MORNING.

PLEASANT AFTERNOON ONGOING WITH WEAK RIDGING ALOFT OVER THE
REGION. RAPIDLY ADVANCING AREA OF STRATUS ACROSS THE NORTHERN HALF
OF ILLINOIS WILL GRADUALLY ENCOMPASS THE TERMINALS...BEGINNING
FIRST AT KLAF BY MID AFTERNOON...KHUF AND KIND TOWARDS SUNSET AND
KBMG BY EARLY EVENING. EXPECT CEILINGS TO DROP TO MVFR AND AS THE
INVERSION STRENGTHENS...IFR CEILINGS WILL DEVELOP THIS EVENING
INTO THE OVERNIGHT. VISIBILITIES WILL ALSO DROP TO 3-5SM AND
POSSIBLY LOWER OVERNIGHT. SOUNDINGS THEMSELVES PRESENT THE
POTENTIAL FOR PATCHY DRIZZLE WITH A DRIER LAYER ABOVE THE BOUNDARY
LAYER. NO PLANS TO MENTION IN THE FORECAST AT THIS POINT BUT THIS
WILL BE SOMETHING TO MONITOR INTO THE EVENING.

WINDS WILL BECOME WESTERLY ON WEDNESDAY WITH ANOTHER UPPER WAVE
DROPPING INTO THE WESTERN GREAT LAKES. SHOULD SEE SOME IMPROVEMENT
IN CEILINGS TO 1500-2000FT BY MIDDAY WEDNESDAY...BUT CLOUDS WILL
REMAIN IN ABUNDANCE WITH TRAPPED LOW LEVEL MOISTURE AND COLD
ADVECTION. 

&&

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SYNOPSIS...MK
NEAR TERM...MK/50
SHORT TERM...MK
LONG TERM...PUMA
AVIATION...RYAN/NIELD

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