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000
FXUS63 KIND 231820
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
220 PM EDT THU MAY 23 2013

.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW.

&&

.SYNOPSIS...
ISSUED AT 420 AM EDT THU MAY 23 2013

A LARGE UPPER LEVEL TROUGH WILL SWING THROUGH THE AREA TODAY
ACCOMPANIED BY A SECONDARY COLD FRONT. THIS WILL BRING SHOWERS
TODAY AND SIGNIFICANTLY COOLER TEMPERATURES INTO THE WEEKEND
ACROSS CENTRAL INDIANA AS A LARGE AREA OF SURFACE HIGH PRESSURE
SETTLES ACROSS THE REGION. THIS WILL ALSO PROVIDE A BREAK FROM THE
RECENT UNSETTLED WEATHER.

&&

.NEAR TERM /TODAY/...
ISSUED AT 420 AM EDT THU MAY 23 2013

FAIRLY STRAIGHTFORWARD FORECAST TODAY. UPPER TROUGH WILL FINALLY
SWING THROUGH THE AREA ALONG WITH A REINFORCING COLD FRONT WHICH
WILL BRING THE SIGNIFICANT COOL DOWN TO THE AREA. TEMPERATURES
WILL LIKELY NOT RISE MUCH IN THE NORTHWESTERN FORECAST AREA TODAY
AS THE FRONT WILL BEGIN TO PUSH INTO THE AREA THIS MORNING. SOME
OPPORTUNITY FOR WARMING WILL EXIST ACROSS THE SOUTHERN FORECAST
AREA THIS MORNING BEFORE THE FRONT AND ASSOCIATED THICK LOW LEVEL
CLOUD COVER SWEEP INTO THE AREA.

THE UPPER TROUGH SHOULD SPARK SOME SCATTERED SHOWERS...ESPECIALLY
LATE THIS MORNING INTO MID AFTERNOON...AS LOW LEVEL MOISTURE
REMAINS...AND SOME VERY WEAK INSTABILITY MAY BE PRESENT AHEAD OF
THE FRONT. HOWEVER...MOST UNSTABLE CAPE VALUES HARDLY EVEN
REGISTER IN THE 100-250 J/KG RANGE...AND EVEN THIS MAINLY ACROSS
THE SOUTHEASTERN THIRD OF THE AREA. WHILE AN ISOLATED RUMBLE OF
THUNDER WOULD NOT BE COMPLETELY SHOCKING...ESPECIALLY IF SOME
MIXING OCCURS AND CREATES SOME BREAKS IN THE CLOUD COVER...THIS
SEEMS UNLIKELY AND LOW PROBABILITY ENOUGH TO CARRY ONLY SHOWERS
AND NO THUNDER MENTION.

A MOS CONSENSUS BUMPED UP SLIGHTLY AND WITH A TIGHTENED GRADIENT
APPEARS BEST ON MAX TEMPS TODAY...AND AGREES WELL WITH UPSTREAM
MAXES. TEMPERATURES ARE LIKELY TO BE FALLING ACROSS MUCH OF THE
AREA THIS AFTERNOON IN THE WAKE OF THE FRONT.

&&

.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 420 AM EDT THU MAY 23 2013

BEYOND A VERY SLIGHT CHANCE OF A LINGERING SHOWER IN THE FAR
EASTERN FORECAST AREA JUST PAST 00Z...SENSIBLE WEATHER IN THE
SHORT TERM WILL BE NIL AS HIGH PRESSURE DROPS INTO THE REGION.
SKIES SHOULD CLEAR QUICKLY ACROSS THE AREA TONIGHT AND THIS ALONG
WITH ONGOING COLD ADVECTION SHOULD ALLOW TEMPS TO BOTTOM OUT IN
THE LOW TO MID 40S. CLEAR SKIES WILL CONTINUE AT LEAST INTO FRIDAY
AND FRIDAY NIGHT. AMPLE SUNSHINE SHOULD ALLOW MAX TEMPS DURING THE
DAY TO EXCEED GUIDANCE BY A DEGREE OR TWO. MIN TEMPS SHOULD WARM
GRADUALLY BUT NOT QUITE AS FAST AS GUIDANCE DEPICTS WITH ONLY SOME
LIMITED MID AND HIGH CLOUD COVER TO INHIBIT OVERNIGHT COOLING
LIKELY LATE IN THE PERIOD.

MODELS DO WANT TO PRODUCE SOME LIGHT QPF SATURDAY AND SATURDAY
NIGHT ALONG A WEAK BAROCLINIC ZONE LIFTING INTO THE AREA.
HOWEVER...FORECAST SOUNDINGS DEPICT VERY DRY LOW LEVELS...AND
APPRECIABLE MOISTURE RETURN WILL BE A STRUGGLE WITH MIDLEVEL
RIDGING ACROSS THE GULF COAST STATES. MAY VERY WELL SEE SOME
THUNDERSTORM DEVELOPMENT OVER THE TOP OF THE UPPER RIDGE IN THE
CENTRAL/NORTHERN PLAINS LATE IN THE SHORT TERM...BUT WITH THE
AFOREMENTIONED DRY AIR AND ESSENTIALLY NIL INSTABILITY...THIS
ACTIVITY WOULD BE UNLIKELY TO PERSIST THIS FAR EAST.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
ISSUED AT 152 AM EDT THU MAY 23 2013

MODELS ARE SIMILAR ENOUGH FOR THE MOST PART THAT THE ALL BLEND
INITIALIZATION WAS USED FOR MOST ITEMS.

A WARM FRONT WILL REMAIN IN THE NEIGHBORHOOD EARLY IN THE
EXTENDED...WHICH WILL ALLOW SOME SHOWERS AND THUNDERSTORMS TO
DEVELOP. LOCATION OF FRONT AND TIMING OF ITS MOVING NORTHEAST
REMAINS SOMEWHAT UNCERTAIN...SO RELUCTANTLY KEPT LOW POPS IN SUNDAY
NIGHT INTO WEDNESDAY /EVEN THOUGH IT LIKELY WILL NOT RAIN EACH
PERIOD/. RIDGING WILL THEN BUILD IN FOR THE END OF THE PERIOD.

TEMPERATURES WILL WARM THROUGH THE PERIOD AS THE FRONT LIFTS
NORTHEAST AND UPPER RIDGING BUILDS IN.

&&

.AVIATION /DISCUSSION FOR 231800Z TAF ISSUANCE/...

ISSUED AT 1247 PM EDT THU MAY 23 2013

GENERALLY MVFR CONDITIONS THROUGH ABOUT THE FIRST HALF OF THE TAF
PERIOD...THEN VFR.

EXTENSIVE MVFR AND PATCHY IFR CONDITIONS EXIST BEHIND A SURFACE
BOUNDARY THAT WILL HAVE PASSED MOST TAF SITES BY SHORTLY AFTER VALID
TIME. MOST CEILINGS ARE BELOW BKN020...SO WILL KEEP CEILINGS THAT
LOW FOR MUCH OF THE AFTERNOON. CANNOT RULE OUT BRIEF PERIODS OF IFR
OR VFR AS CEILINGS BOUNCE AROUND EARLY IN THE PERIOD.

WILL ALLOW A SLOW RISE THROUGH THE MVFR CATEGORY FROM LATE AFTERNOON
INTO THE EVENING HOURS AS TROUGH AXIS EXITS. CLEARING SHOULD WORK IN
LATE EVENING INTO THE EARLY OVERNIGHT. HIGH PRESSURE WILL THEN BUILD
IN AND PROVIDE CLEAR SKIES FOR FRIDAY.

WINDS BECOME GUSTY NORTHWEST TO AROUND 20 MPH BEHIND THE BOUNDARY
AND THESE CONDITIONS SHOULD CONTINUE THROUGH 00Z OR SO.

&&

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

$$

SYNOPSIS...NIELD
NEAR TERM...NIELD
SHORT TERM...NIELD
LONG TERM....50
AVIATION...50

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