000
FXUS63 KIND 231648
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
1248 PM EDT WED APR 23 2014

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

&&

.SYNOPSIS...
ISSUED AT 337 AM EDT WED APR 23 2014

HIGH PRESSURE WILL KEEP THE WEATHER QUIET THROUGH EARLY THURSDAY. A
FRONTAL SYSTEM WILL MOVE THROUGH THE AREA LATE THURSDAY INTO
THURSDAY NIGHT...WITH THE POTENTIAL FOR WIDESPREAD SHOWERS AND
SCATTERED THUNDERSTORMS. DRY WEATHER WILL QUICKLY RETURN UNTIL LATE
IN THE WEEKEND WHEN A STACKED CLOSED LOW DRIFTS EASTWARD INTO THE
REGION...REMAINING IN THE REGION THROUGH THE REMAINDER OF THE
FORECAST PERIOD AND BRINGING REPEATED CHANCES FOR SHOWERS AND
PERHAPS A STORM OR TWO...ALONG WITH SOMEWHAT DREARY CONDITIONS.

&&

.NEAR TERM /REST OF TODAY/...
ISSUED AT 950 AM EDT WED APR 23 2014

NO CHANGES MADE WITH MORNING UPDATE AS FORECAST IS RIGHT ON TRACK.
PREVIOUS DISCUSSION FOLLOWS...

AFTER STARTING OUT COOL...EXPECT AMPLE SUNSHINE TO HELP TEMPS RISE
TO NEAR 60 IN THE NORTH...AND THE MID TO UPPER 60S SOUTH. THIS IS
NEAR TO SLIGHTLY ABOVE A MOS BLEND...AS RAW MODEL TEMPS LOOKED FAR
TOO COLD BASED ON 850 TEMPS AND LOW LEVEL THICKNESSES. MAY SEE A BIT
OF AN INCREASE IN HIGH CLOUD LATE TODAY...BUT LIKELY TOO LATE TO
HAVE A SIGNIFICANT IMPACT ON TEMPS.

&&

.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
ISSUED AT 337 AM EDT WED APR 23 2014

HIGH WILL KEEP WEATHER QUIET THROUGH AT LEAST EARLY THURSDAY. SOME
GUIDANCE CONTINUES TO WANT TO DEVELOP PRECIP ACROSS THE NORTH
TONIGHT ASSOCIATED WITH AN AREA OF MIDLEVEL FRONTOGENESIS...BUT
AMPLE DRY AIR IN THE LOW LEVELS CONTINUES TO SUGGEST THIS IS
OVERDONE.

SOME ADDITIONAL MODEL DISCREPANCIES HAVE CREPT IN BETWEEN THE OLDER
EURO AND THE NEW GFS ON FRONTAL TIMING THURSDAY INTO THURSDAY
NIGHT...BUT FOR NOW WILL CONTINUE WITH WHAT HAS BEEN THE MOST
CONSISTENT SCENARIO THE LAST SEVERAL DAYS...WITH PRECIP INTO THE
AREA NO EARLIER THAN THURSDAY AFTERNOON IN THE WEST...AND ACROSS THE
ENTIRE AREA THURSDAY EVENING. ALTHOUGH SURFACE BASED INSTABILITY IS
MINIMAL...K INDEX VALUES CONTINUE TO SUGGEST THUNDER IS A GOOD
POSSIBILITY AND WILL CARRY SCATTERED THUNDERSTORMS THURSDAY EVENING.
A STRONG STORM OR TWO CANNOT BE ENTIRELY RULED OUT...BUT WIDESPREAD
SEVERE THREAT DOES NOT APPEAR IN THE CARDS...AND INDEED LATEST
CONVECTIVE OUTLOOK SHIFTS THE THREAT FOR THE DAY FURTHER
SOUTHWEST...WHICH APPEARS REASONABLE.

ON TEMPS...MOS BLEND OR SLIGHTLY ABOVE LOOKS BEST FOR MOST PERIODS
AS RAW MODEL NUMBERS CONTINUE TO LOOK TOO COOL...SIGNIFICANTLY SO IN
SOME PERIODS...BASED ON LOW LEVEL THERMAL PROGS.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
ISSUED AT 330 AM EDT WED APR 23 2014

HIGHLY AMPLIFIED BLOCKY PATTERN DEVELOPING ALOFT WITH THE KEY PLAYER
IN WEATHER THROUGHOUT THE EXTENDED BEING AN UPPER LOW WHICH WILL
DEEPEN AS IT MOVES INTO THE CENTRAL PLAINS LATE WEEKEND...BECOME
CUTOFF FROM THE MEAN FLOW...THEN MEANDER SLOWLY EAST INTO THE
EASTERN U S BY THE MIDDLE OF NEXT WEEK. THIS WILL RESULT IN AN
EXTENDED PERIOD OF UNSETTLED WEATHER ACROSS THE REGION BEGINNING
SATURDAY NIGHT AND CONTINUING THROUGH THE END OF THE EXTENDED...AND
LIKELY BEYOND.

THE PRESENCE OF THE UPPER LOW OVER THE HIGH PLAINS ON SUNDAY WILL
PROMOTE SURFACE CYCLOGENESIS IN THE CENTRAL ROCKIES...WITH THE
SURFACE WAVE EJECTING INTO WESTERN KANSAS LATE SUNDAY AND DEEPENING
AS IT DOES SO. A WARM FRONT WILL EXTEND EAST FROM THE SURFACE WAVE
INTO THE REGION WITH SCATTERED CONVECTION BECOMING INCREASING LIKELY
DURING THE SECOND HALF OF THE WEEKEND AND INTO EARLY NEXT WEEK.
WHILE 00Z MODEL GUIDANCE IN RELATIVELY GOOD AGREEMENT ON THE
LOCATION OF THE UPPER LOW AND SURFACE WAVE...THERE REMAIN
DIFFERENCES ON WHERE THE WARM FRONT EVENTUALLY SETS UP. THE ECMWF
REMAINS FURTHEST NORTH...SIMILAR TO ITS 22/12Z RUN...AND PLACES MUCH
OF THE FORECAST AREA WITHIN THE WARM SECTOR. OP GFS AND GGEM REMAIN
SOUTH CLOSER TO THE OHIO RIVER. HAVE BUMPED UP TEMPS A FEW DEGREES
FROM PREVIOUS FORECAST FOR SUNDAY THROUGH TUESDAY BUT SHOULD THE
MORE NORTHERN PLACEMENT TO THE BOUNDARY VIA THE ECMWF SOLUTION BE
REALIZED...TEMPS WILL NEED TO BE RAISED FURTHER. WILL CONTINUE TO
MONITOR.

REGARDLESS OF THE EXACT PLACEMENT OF THE FRONT...HIGH CHANCE POPS
ARE WARRANTED FROM SUNDAY THROUGH THE MIDDLE PART OF NEXT WEEK AS
THE SURFACE WAVE DRIFTS EAST INTO THE OHIO VALLEY BY THE END OF THE
PERIOD. SIGNS CONTINUE TO POINT TO THE UPPER LOW CARVING OUT A BROAD
TROUGH OVER THE EASTERN HALF OF THE COUNTRY...RESULTING IN AN
EXTENDED PERIOD OF COOL DAMP WEATHER POSSIBLY IMPACTING CENTRAL
INDIANA THROUGH THE END OF NEXT WEEK.

&&

.AVIATION /DISCUSSION FOR THE 231800Z TAFS/...

ISSUED AT 1230 PM EDT WED APR 23 2014

VFR CONDITIONS ARE EXPECTED THIS TAF PERIOD.

HIGH PRESSURE OVER THE WESTERN GREAT LAKES AND INDIANA WILL
CONTINUE TO SLOWLY SLIDE EAST DURING THE PERIOD. MEANWHILE A WARM
FRONT OVER IOWA AND MISSOURI WILL PUSH EAST TOWARD INDIANA
TONIGHT. THIS WILL BRING MID AND HIGH CLOUD CEILINGS TO THE TAF
SITES. TIME HEIGHTS AT THAT TIME FAIL TO SHOW DEEP MOISTURE AS DO
FORECAST SOUNDINGS. THUS WILL TREND TOWARD JUST THE VFR CEILINGS.

TAF SITES SPEND MUCH OF THE THURSDAY AFTERNOON IN THE WARM SECTOR
WITH MINIMAL LOWER LEVEL MOISTURE AND HIGH CLOUD IN PLACE ALOFT.
BETTER CHANCES FOR RAIN RESUME ON LATE THURSDAY AFTERNOON AS THE
300K GFS ISENTROPIC SURFACE SHOWS GOOD LIFT AND MOISTURE ARRIVING
AHEAD OF THE COLD FRONT NEAR 00Z THURSDAY.

&&

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

$$

SYNOPSIS...NIELD
NEAR TERM...NIELD/CP
SHORT TERM...NIELD
LONG TERM...RYAN
AVIATION...JP

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