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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
605 PM EST THU FEB 26 2015

.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.

&&

.SYNOPSIS...
ISSUED AT 340 PM EST THU FEB 26 2015

A FEW FLURRIES MAY LINGER INTO THIS EVENING. OTHERWISE...PARTIAL 
CLEARING WILL BE THE RULE LATE TONIGHT AND FRIDAY AS ARCTIC HIGH 
PRESSURE OVER THE NORTHERN PLAINS BUILDS OUR WAY.  THIS HIGH 
PRESSURE WILL MOVE ON TO SOUTHERN NEW ENGLAND BY SATURDAY AND A 
STRONG UPPER DISTURBANCE WILL MOVE OUR WAY LATE SATURDAY NIGHT AND 
SUNDAY BRINGING ACCUMULATING SNOWS TO NORTH AND CENTRAL SECTIONS AND 
MIXED PRECIPITATION TO OUR SOUTH.

THERE WILL BE A BREAK MONDAY AND THEN ANOTHER SYSTEM WILL BRING 
RAIN TO OUR SYSTEM BY TUESDAY.  THIS PRECIPITATION MAY BEGIN AS 
FREEZING RAIN MONDAY NIGHT AND MIXED PRECIPITATION IS POSSIBLE OVER 
NORTHERN SECTIONS TUESDAY NIGHT AND WEDNESDAY.  FINALLY THERE IS A 
SLIGHT CHANCE OF LIGHT SNOW WEDNESDAY NIGHT AND THURSDAY AS COLDER 
AIR MOVES BACK INTO OUR REGION.

&&

.NEAR TERM /TONIGHT AND FRIDAY/...
ISSUED AT 340 PM EST THU FEB 26 2015

SATELLITE INDICATED LOTS OF CLOUDS ACROSS INDIANA AND MOST OF 
ILLINOIS. LIGHT SNOW SHOWERS WERE OCCURRING ACROSS PARTS OF 
ILLINOIS. WITH LOSS OF DAY TIME HEATING...EXPECT ONLY A FEW FLURRIES 
THIS EVENING AND THEN DECREASING CLOUDS LATER TONIGHT AS DRIER AIR 
SPREADS IN. 

THE MAIN ISSUE TONIGHT WILL BE VERY COLD TEMPERATURES ALONG WITH 
LIGHT WINDS.  THERE SHOULD BE PRETTY GOOD RADIATIONAL COOLING LATE 
TONIGHT AND CUT TEMPERATURES A LITTLE.  I WAS A LITTLE MORE 
CONSERVATIVE WITH MY TEMPERATURES HOWEVER...AS SKIES MAY NOT CLEAR 
COMPLETELY.  NERVELESS IT LOOKS LIKE NORTHERN SECTIONS MAY BE COLD 
ENOUGH LATE TONIGHT AND FRIDAY MORNING FOR LOWEST WINDS CHILLS NEAR 
15 BELOW.  THUS WILL ISSUE A WIND CHILL ADVISORY FROM 4 AM TO 11 AM 
FOR THE NORTHERN THIRD TO HALF OF OUR REGION.

FRIDAY WILL BE MOSTLY SUNNY AS HIGH PRESSURE MOVES EAST ACROSS OUR 
REGION. EVEN THOUGH AIR MASS IS QUITE COLD...WENT SLIGHTLY ABOVE MOS 
TEMPERATURES GIVEN A DECENT AMOUNT OF SUNSHINE FRIDAY.    

LOWS TONIGHT WILL RANGE FROM 4 BELOW NORTHEAST TO 6 ABOVE SOUTH AND 
HIGHS FRIDAY WILL RANGE FROM THE LOWER TEENS NORTH TO NEAR 20 SOUTH.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
ISSUED AT 340 PM EST THU FEB 26 2015

HIGH PRESSURE WILL CONTINUE TO BRING COLD BUT QUIET WEATHER FRIDAY 
NIGHT AND SATURDAY AS IT MOVES TO SOUTHERN NEW ENGLAND. THEN ALL 
MODELS SPREAD PRECIPITATION ACROSS OUR REGION LATER SATURDAY NIGHT 
THROUGH SUNDAY EVENING AS A UPPER DISTURBANCE MOVES ACROSS OUR 
REGION.  LOW LEVEL THICKNESS INDICATE ALL SNOW OVER NORTHERN 
SECTIONS...WHILE SOUTHERN SECTIONS MAY START OUT AS SNOW AND THEN 
CHANGE TO RAIN SUNDAY.  THERE MAY ALSO BE A PERIOD OF FREEZING RAIN 
DURING THIS CHANGE OVER.   WENT CLOSE TO HPC SNOW AMOUNTS WHICH 
INDICATED 5 TO 7 INCHES FAR NORTH TO MAYBE AN INCH OR TWO SOUTH.
THE NAM INDICATED PRECIPITATION SHOULD BE OVER BY SUNDAY 
EVENING...WHILE THE GFS WAS ALMOST 12 HOURS LATER IN ENDING 
PRECIPITATION.  WENT WITH A BLEND WITH PRECIPITATION ENDING MOST 
AREAS BY LATE SUNDAY EVENING.

CONCERNING TEMPERATURES...WENT WITH A MOS BLEND MOST AREAS.  
TEMPERATURES MAY RISE A LITTLE LATE SATURDAY NIGHT AND ON SUNDAY CUT 
A FEW DEGREES ACROSS NORTHERN SECTIONS.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
ISSUED AT 249 PM EST THU FEB 26 2015 

FOR THE MOST PART...MODELS ARE CLOSE ENOUGH IN THE BIG PICTURE THAT 
THE SUPERBLEND INITIALIZATION WAS ACCEPTED FOR MOST ITEMS. 
HOWEVER...SOME CHANGES NOTED BELOW.

UPPER FLOW WILL BE SOUTHWEST ACROSS CENTRAL INDIANA THROUGH MUCH OF 
THE PERIOD...ALLOWING TEMPERATURES NEAR TO PERHAPS ABOVE NORMAL 
ALONG WITH GOOD CHANCES FOR PRECIPITATION.

MONDAY SHOULD BE DRY IN BETWEEN SYSTEMS. HOWEVER MOISTURE AND 
FORCING ARRIVE MONDAY NIGHT AND RAMP UP TUESDAY AS A LOW PRESSURE 
SYSTEM MOVES IN. GFS LOOKS JUST TOO AGGRESSIVE IN BRINGING IN WARM 
AND MOIST AIR...EVEN BRINGING SURFACE DEWPOINTS NEAR 60 TO FAR 
SOUTHERN SECTIONS OF CENTRAL INDIANA. PREFER GOING CLOSER TO THE 
ECMWF WHICH IS NOT AS AGGRESSIVE.

THUS CUT SUPERBLEND/S TEMPERATURES TUESDAY INTO WEDNESDAY. STILL 
SOME PRECIPITATION TYPE QUESTIONS WHICH WILL DEPEND ON HOW FAST 
PRECIPITATION ARRIVES MONDAY NIGHT AS WELL AS THE WARM AIR. WILL 
KEEP A WINTRY MIX GOING MONDAY NIGHT WITH FREEZING RAIN MENTIONED 
EARLY TUESDAY. ENOUGH COLD AIR WILL SNEAK BACK IN TUESDAY 
NIGHT/WEDNESDAY TO GO RAIN/SNOW NORTH AND RAIN SOUTH.

UPPER TROUGH BUILDS INTO THE AREA ON THURSDAY. NOT CONFIDENT THAT 
ANY PRECIPITATION WILL OCCUR BUT WILL KEEP TOKEN 20 POPS FOR NOW.

&&

.AVIATION /DISCUSSION FOR THE 270000Z TAF ISSUANCE/...

ISSUED AT 601 PM EST THU FEB 26 2015

PREDOMINANT VFR EXPECTED. POSSIBLY SOME MVFR IN SOME OF THE WIDELY
SCATTERED LIGHT SNOW SHOWERS AND/OR FLURRIES. 

OTHERWISE EXPECT GENERAL VFR CONDITIONS FOR THE TAF PERIOD. MOST
CEILINGS WILL BREAK UP AND SCATTER OUT OVERNIGHT...WITH PERHAPS
THE EXCEPTION OF A LAKE BAND OF CLOUDS THAT WILL PASS SOMEWHERE
OVER THE AREA.

VFR EXPECTED FRIDAY.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY FROM 4 AM TO 11 AM EST FRIDAY FOR INZ021-
028>031-035>044-048-049-057.

&&

$$

SYNOPSIS...JH
NEAR TERM...JH
SHORT TERM...JH
LONG TERM...50
AVIATION...SMF

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