470 
FXUS63 KIND 061825
AFDIND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
224 PM EDT TUE AUG 6 2013

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

&&

.SYNOPSIS...
ISSUED AT 243 AM EDT TUE AUG 6 2013

WARMER AIR IS SET TO ARRIVE IN INDIANA TODAY AS HIGH PRESSURE OVER
THE EAST COAST PROVIDES A WARMER AND MORE HUMID SOUTHERLY FLOW
ALONG WITH DRY WEATHER. A MORE ACTIVE WEATHER PATTERN WILL TAKE
SHAPE THROUGH THE MIDDLE OF THE WEEK AS A COLD FRONT IS EXPECTED
TO PUSH TOWARD INDIANA LATE TONIGHT AND STALL ACROSS SOUTHERN
INDIANA THROUGH THURSDAY THE FRONT WILL BRING CHANCES FOR SHOWERS
AND STORMS FROM LATE TONIGHT THROUGH FRIDAY.

HIGH PRESSURE IS EXPECTED TO ARRIVE LATE FRIDAY AND BRING A RETURN
TO DRY WEATHER FOR THE WEEKEND.

&&

.NEAR TERM /REST OF TODAY/...

ISSUED AT 944 AM EDT TUE AUG 6 2013

BUMPED UP CLOUD COVER THIS MORNING DUE TO SATELLITE TRENDS AS LOW
DECK HAS BEEN OVERSPREADING THE AREA. LOOKS LIKE IT WILL TAKE A
BIT LONGER TO SCATTER OUT AND THUS TRENDED MOSTLY CLOUDY TO LAST
THROUGH MID AFTERNOON FOR MOST OF THE AREA. WITH THIS INCREASE IN
CLOUD COVER HAVE ALSO LOWER HIGH TEMPERATURES FOR THE DAY...ONLY
BY A DEGREE OR SO IN THE NORTH AND CENTRAL BUT BY A FEW DEGREES IN
THE SOUTHWEST SINCE DEBRIS CLOUDS WILL LIKELY KEEP THAT AREA
MOSTLY CLOUDY THROUGH MUCH OF THE DAY. RAP SHOWS SOME ISOLATED TO
SCATTERED CONVECTIVE DEVELOPMENT LATER THIS AFTERNOON BUT OTHER
MODELS STILL LOOK DRY. WITH SOME SUBSIDENCE AND DRY AIR ALOFT AND
THE RAP ALSO SHOWING SOME THINGS NOW THAT ARE NOT OCCURRING WILL
CONTINUE WITH DRY FORECAST THROUGH THE DAY.

&&

.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
ISSUED AT 243 AM EDT TUE AUG 6 2013

MAIN FOCUS DURING THIS PERIOD WILL BE POPS.

MODELS ARE IN PRETTY GOOD AGREEMENT OF THE OVERALL TREND OF A
WET...ACTIVE PATTERN. 

GFS AND NAM BOTH SUGGEST THE FIRST SHORT WAVE ARRIVING IN THE AREA
LATE TONIGHT AMID THE NW FLOW ALOFT. FORECAST SOUNDINGS HINT AT A
SLOW TOP DOWN STYLE SATURATION BY 12Z. THUS WILL KEEP THE EVENING
DRY...BUT TREND TOWARD HIGHER CHANCES FOR RAIN DURING THE
OVERNIGHT HOURS. 310K GFS ISENTROPIC SURFACE ALSO SHOWS A GOOD
SURGE OF ISENTROPIC LIFT WITH SPECIFIC HUMIDITIES RISING TO NEAR
8 G/KG. WILL TREND LOWS AT OR ABOVE MAVMOS VALUES DUE TO EXPECTED
WARM AIR ADVECTION...CLOUDS...AND PRECIP.

ON WEDNESDAY MORNING...THE GFS AND NAM SUGGEST A COLD FRONT
TROUGH LINGERING ACROSS THE STATE AS THE UPPER SUPPORT FROM THE
OVERNIGHT PERIOD DEPARTS. FORECAST SOUNDINGS SUGGEST DRYING
OUT...HOWEVER PLENTY OF CAPE...IN EXCESS OF 2000 J/KG REMAINS
AVAILABLE. PWATS ARE ALSO NEAR 1.75 INCHES...VERY MOIST. CONVECTIVE
TEMPS ON WEDNESDAY AFTERNOON ARE VERY ATTAINABLE...IN THE LOWER
80S...AND THE GFS 310K ISENTROPIC SURFACE SHOWS STRONG LIFT WITH
AGAIN A VERY MOIST AIR MASS WITH SPECIFIC HUMIDITIES OVER 9 G/KG.
MEANWHILE AT THE SURFACE A WARM FRONT STALLS ACROSS SOUTHERN
INDIANA...FURTHER ACTING AS A FOCUS FOR LOWER LEVEL CONVERGENCE.
THUS ANY HEATING ON WEDNESDAY SHOULD LEAD TO DEVELOPMENT. WILL
TREND POPS AT OR ABOVE MAVMOS...PARTICULARLY DURING THE AFTERNOON. 
GIVEN THE EXPECTED CLOUDS AND RAIN...WILL TREND HIGHS AT OR BELOW 
MAVMOS.

GFS DEPICTS A SHORT WAVE RIDING ACROSS THE WARM FRONT ACROSS THE
SOUTHERN PARTS OF THE FORECAST AREA ON WEDNESDAY NIGHT...AGAIN A
VERY WARM AND MOIST AIR MASS WILL REMAIN IN PLACE. FORECAST
SOUNDINGS ACROSS THE AREA ALSO INDICATE DEEP SATURATION BY
THURSDAY...AND NOW WITH PWATS IN EXCESS OF 2 INCHES. FAVORABLE
CAPE IS ALSO AVAILABLE. ALOFT IT APPEARS AS IF THE TROPICAL PLUME
THAT IS CURRENTLY FLOWING ACROSS THE PLAINS INTO THE DEEP SOUTH WILL
SHIFT EAST BY WEDNESDAY AND THURSDAY...ALLOWING THIS DEEPER
MOISTURE TO SURGE INTO INDIANA AND THE OHIO VALLEY...PARTICULARLY
ACROSS THE SOUTHERN PARTS OF OUR STATE. THUS WILL CONTINUE TO
RAISE POPS THROUGH THURSDAY NIGHT...TRENDING HIGHS COOLER THAN
MAVMOS AND LOWS WARMER...GIVEN THE EXPECTED CLOUDS AND RAIN.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
ISSUED AT 224 PM EDT TUE AUG 6 2013

EXTENDED MODELS IN FAIR AGREEMENT ON A COLD FRONT DROPPING TO NEAR 
THE OHIO RIVER 12Z SATURDAY WITH NORTHWEST FLOW LOFT. THE FRONT 
SHOULD SETTLE GRADUALLY FURTHER SOUTH THROUGH THE WEEKEND WITH HIGH 
PRESSURE BUILDING IN BEHIND THE FRONT. THIS SCENARIO SUGGESTS 
THUNDERSTORM CHANCES FRIDAY NIGHT...WITH MOSTLY SMALL POPS AND 
MAINLY ACROSS THE SOUTH...THEREAFTER. HAD TO TINKER ABOUT WITH 
REGIONAL ALLBLEND TO REFLECT THAT. THIS FAMILIAR RECENT PATTERN ALSO 
STRONGLY SUGGESTS BELOW NORMAL TEMPERATURES ONCE AGAIN. REGIONAL 
INITIALIZATION HAD A GOOD HANDLE ON THAT. 

&&

.AVIATION /DISCUSSION FOR 141800Z TAF ISSUANCE/...
ISSUED AT 100 PM EDT SUN JUL 14 2013

MVFR CEILINGS LOOK LIKE THEY PERSIST ALL DAY PER MODEL 
SOUNDINGS...CONVECTIVE CONDENSATION LEVELS AND CU DEVELOPMENT PROGS. 
HOWEVER...WOULD NOT RULE OUT CEILINGS TO 3500 FEET AFTER 20Z IF ANY 
BREAKS OCCUR IN THE OVERCAST. OTHERWISE...SHOULD BE DRY UNTIL AFTER 
00Z. THEN...ILL-DEFINED WARM FRONT IS EXPECTED TO MOVE THROUGH AFTER 
04Z. WOULD NOT RULE OUT STORMS ALONG AND AHEAD OF THE WARM 
FRONT...HOWEVER WITH CONVERGENCE WEAK...AND LITTLE GOING ON NOW 
AHEAD OF THE FRONT...WILL LEAVE OUT MENTION OF THUNDER OVERNIGHT AND 
JUST GO WITH VCTS AFTER 20Z WEDNESDAY AT IND ASSOCIATED WITH A COLD 
FRONT APPROACHING FROM THE NORTHWEST. 

SOUTH AND SOUTHWEST WINDS WILL BE 10 KNOTS OR LESS THROUGH THE 
PERIOD. FINALLY...WILL THROW IN MVFR FOG AFTER 09Z AS DEW POINTS 
INCREASE TO AROUND 70 BEHIND THE WARM FRONT.

&&

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

$$

SYNOPSIS...PUMA
NEAR TERM...CP
SHORT TERM...PUMA
LONG TERM....MK
AVIATION...MK

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