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000
FXUS63 KIND 072011
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
313 PM EST SAT DEC 7 2013

.UPDATE...

THE AVIATION SECTION HAS BEEN UPDATED BELOW.

&&

.SYNOPSIS...
ISSUED AT 149 PM EST SAT DEC 7 2013

DRY AND COLD WEATHER IS EXPECTED TONIGHT AS HIGH PRESSURE MOVES
ACROSS INDIANA AND BEGINS TO DEPART TO THE EAST. AS THE HIGH MOVES
TO THE EAST...SLIGHTLY WARMER AIR WILL ARRIVE ON SUNDAY. THIS
ALONG WITH A PASSING UPPER LEVEL WEATHER DISTURBANCE WILL RESULT
IN CLOUD COVER ALONG WITH CHANCES FOR SOME LIGHT SNOW SHOWERS.
SOME MIXED PRECIPITATION MAY ALSO DEVELOP ACROSS SOUTHERN CENTRAL
INDIANA BY LATE SUNDAY AFTERNOON.

ANOTHER AREA OF ARCTIC HIGH PRESSURE WILL BUILD ACROSS CENTRAL
INDIANA IN THE WAKE OF SUNDAY NIGHT/S SYSTEM...BRING DRY BUT VERY
COLD WEATHER FOR MUCH OF THE NEXT WORK WEEK.

&&

.NEAR TERM /TONIGHT/...
ISSUED AT 149 PM EST SAT DEC 7 2013

SURFACE ANALYSIS EARLY THIS AFTERNOON SHOWS HIGH PRESSURE OVER
IOWA. A COLD AND DRY NORTHWESTERLY FLOW WAS IN PLACE OVER CENTRAL
INDIANA WITH TEMPERATURES NEAR 20. DEW POINTS WERE DRY...IN THE
SINGLE DIGITS. WATER VAPOR IMAGERY SHOWS A QUICK SOUTHWEST FLOW
ALOFT...HOWEVER THE PLUME OF MOISTURE THAT BROUGHT YESTERDAY/S
SNOWS WAS NOW FAR SOUTH OF INDIANA...STREAMING OVER THE TENNESSEE
VALLEY INTO THE VIRGINIA/S.

FORECAST SOUNDINGS AND TIME HEIGHTS REVEAL A DRY COLUMN ACROSS
INDIANA THIS EVENING AS THE HIGH PRESSURE SYSTEM PASSES ACROSS THE
STATE. AFTER 06Z 850MB SURFACES SHOWS SOME WARM AIR ADVECTION
BEGINNING...BUT THE COLUMN STILL REMAIN VERY DRY. WILL AIM FOR
MOSTLY CLEAR SKY TONIGHT AND TREND SKY GRIDS HIGHER TOWARD
DAYBREAK FOR SOME HIGH CLOUDS IN THE WAA...BUT MOSTLY CLEAR SHOULD
STILL BE THE END RESULT.

AS FOR TEMPS WILL TREND LOWS COOLER THAN MAVMOS GIVEN THE FRESH
SNOW PACK ACROSS MOST AREAS.

&&

.SHORT TERM /SUNDAY THROUGH TUESDAY/...
ISSUED AT 149 PM EST SAT DEC 7 2013

MODELS REMAIN IN PRETTY GOOD AGREEMENT DURING THIS PERIOD AND WILL
USE A BLEND. MAIN FORECAST CHALLENGE WILL BE PRECIPITATION TYPE.

GFS 295K ISENTROPIC SURFACE CONTINUES TO SHOW GOOD UPGLIDE AMID
WARM AIR ADVECTION ON SUNDAY AFTERNOON. SPECIFIC HUMIDITIES LOOK
TO CLIMB TO NEAR 4 G/KG. HOWEVER FORECAST SOUNDINGS KEEP THE
FORECAST COLUMN BELOW FREEZING THROUGH AT LEAST 21Z ACROSS MUCH OF
THE FORECAST AREA. ALSO...THE BEST FORCING ALOFT IS WELL TO THE
NORTH. ALSO LOWER LEVEL WILL BE VERY DRY AMID A DRY EASTERLY FLOW.
TIME HEIGHT SECTIONS DO SHOW SOME GOOD LOWER LEVEL AND MID LEVEL
SATURATION BY THE AFTERNOON...WITH BEST SATURATION ACROSS THE
SOUTHERN PARTS OF THE FORECAST AREA. ALSO...AFT 21Z...FORECAST
SOUNDINGS APPEAR TO TREND WARM ENOUGH ACROSS THE SOUTHERN PARTS OF
THE FORECAST AREA TO SUPPORT SOME MIXED PRECIPITATION. THUS WILL
HAVE THE HIGHEST POPS ACROSS THE SOUTH AND TREND LOWER NORTHWARD.
WILL ALSO KEEP THE MIX PRECIP LIMITED TO AREAS SOUTH OF I70...AND
MAINLY IN A BRIEF WINDOW BETWEEN 21Z SUN AND ABOUT 02Z MONDAY.

BY 06Z MONDAY/SUNDAY NIGHT/ ISENTROPIC FORCING IS LOST AS IS THE
WEAK SHORT WAVE ALOFT...QUICKLY MOVING TO THE NORTHEAST. HOWEVER
FORECAST SOUNDING CONTINUE TO SHOW A SATURATED LOWER LEVEL WITH
DRY AIR ALOFT WITH MINIMAL FORCING...WHICH IS INDICATIVE OF
FREEZING DRIZZLE. ALTHOUGH POPS WILL BE DONE ON LATE SUNDAY
NIGHT...WILL KEEP A MENTION OF THE FREEZING DRIZZLE...PARTICULARLY
ACROSS THE SOUTHERN PARTS OF THE FORECAST AREA. AS FOR HIGHS AND
LOWS...A BLEND OF THE MAVMOS AND METMOS SHOULD WORK JUST FINE.

ON MONDAY AND MONDAY NIGHT FORECAST SOUNDINGS BECOME QUITE DRY
ONCE AGAIN AS QUICK SW FLOW PERSISTS ALOFT. LOWER LEVEL MOISTURE
LOOKS TO LINGER HOWEVER...AND WILL KEEP A MOSTLY CLOUDY AND COLD
DAY IN STORE. THE NEXT BURST OF COLD AIR BEGINS TO ARRIVE ON
MONDAY NIGHT AS FLOW BECOMES MORE NORTHWESTERLY. GFS AND NAM
APPEAR TO SATURATE THE COLUMN A BIT...BUT CONFIDENCE REMAINS FLOW
AS A MOISTURE SOURCE APPEARS SUSPECT AND FORCING IS WEAK. WILL
KEEP PLENTY OF CLOUDS ALONG WITH A SMALL SNOW CHCS ON MONDAY
NIGHT...ALTHOUGH ANY PRECIP SHOULD BE VERY LIGHT. CONFIDENCE IN
THESE FEATURES REMAIN VERY LOW. WITH THE STRONG COLD AIR ADVECTION
EXPECTED IN THE AREA ON MONDAY NIGHT INTO TUESDAY...WILL TREND
LOWS AND HIGHS COOLER THAN MAVMOS.


&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
ISSUED AT 200 PM EST SAT DEC 7 2013

HIGH PRESSURE WILL BE THE DOMINANT FORCE THROUGH THE MAJORITY OF THE
LONG TERM. A DRY COLD FRONT MAY PASS THROUGH THE AREA EARLY IN THE
PERIOD...BUT ASIDE FROM THIS MODELS HAVE TRENDED DRIER AND DRIER
LATER IN THE WEEK. WILL GO WITH A DRY FORECAST THROUGH THE END OF
THE PERIOD.

TEMPERATURES SHOULD SEE A GRADUAL WARMING TREND...WITH HIGHS BACK
INTO THE 30S BY NEXT WEEKEND. ALLBLEND HANDLED THIS WELL AND FEW
CHANGES WERE REQUIRED.

&&

.AVIATION /DISCUSSION FOR THE 07/21Z TAFS/...

ISSUED AT 313 PM EST SAT DEC 7 2013

UPDATED CURRENT CONDITIONS ONLY. PREVIOUS DISCUSSION FOLLOWS...

VFR THROUGH THE MAJORITY OF THE PERIOD. WINTRY WEATHER AND
RESTRICTIONS MAY RETURN VERY LATE IN THE PERIOD.

HIGH PRESSURE IN PLACE ACROSS THE AREA AND MOSTLY CLEAR SKIES ALONG
WITH WINDS LESS THAN 10KT WILL PERSIST THROUGH THIS EVENING. AS THE
NEXT SYSTEM APPROACHES...MID AND HIGH CLOUDS WILL INCREASE AND
GRADUALLY LOWER AND WINDS WILL BECOME MORE EASTERLY...STILL
REMAINING BELOW 10KT.

LATE IN THE PERIOD...AFTER 12-15Z TOMORROW...SNOW SHOWERS MAY
OVERSPREAD THE SITES. UNCERTAINTY REMAINS AS TO LOW LEVEL DRY AIR
AND IMPACT ON POSSIBLE RESTRICTIONS...SO WILL JUST TAKE THINGS DOWN
TO THE BORDERLINE OF MVFR. IN THE 30 HOUR PERIOD AT IND...AND AFTER
THE OTHER TAF PERIODS...POTENTIAL WILL EXIST FOR FREEZING DRIZZLE
AND POSSIBLY IFR CONDITIONS...BUT THIS IS VERY UNCERTAIN AND WILL
LEAVE OUT AT THIS TIME.

&&

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

&&

$$

SYNOPSIS...PUMA
NEAR TERM...PUMA
SHORT TERM...PUMA
LONG TERM...NIELD
AVIATION...NIELD/CP

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