Tornadoes in Indiana, June 6, 2010

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
100 AM EDT SUN JUN 6 2010

.UPDATE...
UPDATED AVIATION SECTION.

&&

.SYNOPSIS...
LOW PRESSURE LOCATED OVER NORTHERN ILLINOIS WILL TRACK RAPIDLY EAST
ACROSS THE SOUTHERN GREAT LAKES TONIGHT.  A TRAILING COLD FRONT FROM
THE LOW TO NORTHERN MISSOURI WILL MOVE INTO NORTHWEST INDIANA BY 06Z
AND TO NEAR THE OHIO RIVER BY 12Z SATURDAY.  NUMEROUS THUNDERSTORMS
WERE OCCURRING ALONG AND AHEAD OF COLD FRONT.  AS FRONT
APPROACHES...CHANCES FOR SEVERE WEATHER WILL INCREASE ACROSS CENTRAL
INDIANA OVER THE NEXT SEVERAL HOURS.

&&

.NEAR TERM /TONIGHT AND SUNDAY/...

NUMEROUS THUNDERSTORMS...SOME SEVERE WERE OCCURRING ACROSS NORTHERN
ILLINOIS TO NORTHERN MISSOURI. THESE THUNDERSTORMS SHOULD REACH OUR
FAR NORTHWEST SHORTLY BEFORE MIDNIGHT AND SPREAD SOUTHEAST ACROSS
CENTRAL INDIANA SHORTLY AFTER MIDNIGHT. HAVE ADJUSTED TIMING A
LITTLE TOWARDS RAPID REFRESH MODEL. GRIDDS HAVE BEEN UPDATED TO
REFLECT THE SLOWER ONSET OF STORMS.  HOWEVER SINCE TORNADO WATCH
WILL LIKELY BE ISSUED IN THE NEXT HOUR WILL HOLD OFF ON ZFP PRODUCT
UNTIL NEW WATCH IS ISSUED.

THE CONVECTION DEVELOPING BACK NEAR THE LOW WILL IS EXPECTED TO BE
MORE SIGNIFICANT AND HAVE THE BEST CHANCE AT PRODUCING SEVERE
WEATHER ACROSS THE FORECAST AREA AS IT EXPANDS SOUTH AND EAST INTO
OUR NORTHERN COUNTIES DURING THE EVENING.

0-1KM SRH REMAIN EXTREMELY IMPRESSIVE AHEAD OF THE LOW THIS
EVENING...AND WITH BL SHEAR INCREASING TO NEAR 50KTS AHEAD OF THE
UPPER TROUGH AND EXCELLENT DIFFLUENCE ALOFT...EXPECT THUNDERSTORMS
WILL CONSOLIDATE INTO A BOW ECHO OR DERECHO WITH EMBEDDED SUPERCELLS
AND IMPACT NORTHERN COUNTIES AFTER SUNSET. DAMAGING WINDS REMAIN THE
GREATEST CONCERN...WITH LARGE HAIL AND ISOLATED TORNADOES ALSO
POSSIBLE. THE STORMS SHOULD EXHIBIT A GRADUAL WEAKENING TREND AS
THEY SURGE SOUTH OVERNIGHT THROUGH THE FORECAST AREA AND
HEATING/INSTABILITY WANES. THESE STORMS WILL ALSO PRODUCE TORRENTIAL
RAINFALL WITH PWATS HOVERING NEAR 2 INCHES. WHILE LOCALIZED FLOODING
WILL BE POSSIBLE...RELATIVELY FAST STORM MOTION SHOULD KEEP STORMS
FROM TRAINING.

SHOWERS MAY LINGER FOR A FEW HOURS ACROSS THE SOUTHEAST COUNTIES
SUNDAY MORNING. LOW CLOUDS WILL SLOWLY LIFT OUT INTO A CUMULUS FIELD
BY EARLY AFTERNOON AS DRIER AIRMASS EXPANDS INTO THE REGION AND COLD
ADVECTION PERSISTS. MODEL GUIDANCE CONTINUES TO ADVERTISE SOME WEAK
INSTABILITY BELOW A MID LEVEL CAP SUNDAY AFTERNOON AND EVENING. THIS
MAY BE ENOUGH TO GENERATE AN ISOLATED SHOWER OR TWO AS MID LEVEL
SHORT WAVE PASSES THROUGH NORTHERN INDIANA. WITH COVERAGE EXPECTED
TO BE SPARSE AND PRESENCE OF THE CAPPING INVERSION...HAVE CONTINUED
TO KEEP ANY PRECIP MENTION OUT OF THE FORECAST DURING THIS
TIMEFRAME. NORTHWEST WINDS WILL BE GUSTY THROUGHOUT THE DAY.

TEMPS...NEAR WARMER MAVMOS GUIDANCE FOR LOWS OVERNIGHT WITH CLOUDS
AND PRECIP FOR MUCH OF THE NIGHT. WENT A DEGREE OR TWO WARMER THAN
MOS SUNDAY WITH EXPECTED SUNSHINE IN THE AFTERNOON AND SUGGESTED LOW
LEVEL THICKNESSES.

&&

.SHORT TERM /SUNDAY NIGHT AND MONDAY/...
MODELS IN AGREEMENT AND APPEAR REASONABLE ON BUILDING SURFACE HIGH
PRESSURE ACROSS THE GREAT LAKES AND OHIO VALLEY ON SUNDAY NIGHT AND
MONDAY AS A RIDGE AMPLIFIES ACROSS THE PLAINS AND AN UPPER LOW SPINS
OVER QUEBEC. THIS SHOULD RESULT IN A DRY PERIOD IN THE NORTHWEST
FLOW. COULD SEE SOME CIRRUS OR AC AS IMPULSES DIVE SOUTHEAST OVERTOP
THE UPPER RIDGE ACROSS THE OHIO VALLEY. 850 MILLIBAR TEMPERATURES
MIXED DOWN AND SOME CLOUDS FAVOR THE NOT AS WARM MAV GUIDANCE.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
UPPER RIDGE WILL GRADUALLY MOVE EAST NEXT WEEK AND BUILD ACROSS THE
SOUTH AND OHIO VALLEY LATE IN THE WEEK. PRIOR TO THE RIDGE BUILDING
ACROSS THE OHIO VALLEY...SEVERAL SHORT WAVES ARE EXPECTED TO MOVE
THROUGH THE FLATTENING FAST UPPER FLOW AND RESULT IN ANOTHER
UNSETTLED PERIOD WITH POTENTIAL MCS ACTIVITY STARTING MONDAY NIGHT
AND CONTINUING THROUGH MID WEEK. COULD ALSO SEE SOME STORMS ON
FRIDAY AS MODELS HAVE THE NORTHERN PERIPHERY OF THE UPPER RIDGE
ACROSS THE LOWER GREAT LAKES WITH VARIOUS DISTURBANCES PASSING
THROUGH. WILL HAVE TO WATCH OUT FOR HYDRO ISSUES THROUGH THE WEEK AS
THE STORMS THIS WEEKEND COULD AGAIN SATURATE THE GROUNDS. WITH THE
UPPER RIDGE BUILDING ACROSS THE OHIO VALLEY LATE WEEK...COULD EVEN
SEE TEMPERATURES IN THE 90S ACROSS THE SOUTHWEST BY FRIDAY.
HOWEVER...HPC FAVORING THE SLOWER ECMWF SOLUTION REGARDING THE UPPER
RIDGE BUILDING AND AS IT TENDS TO DO BETTER IN THE EXTENDED WITH
OVERALL SYNOPTIC PATTERN. STILL 90 DEGREES LOOKS REACHABLE ON FRIDAY
AND CERTAINLY BY SATURDAY.

&&

.AVIATION.../060600Z TAFS/...

A BROKEN LINE OF TSRA WILL MOVE ACROSS CENTRAL INDIANA THROUGH 09Z
OR SO. BASED ON CURRENT RADAR TRENDS...WENT TSRA WHERE CONFIDENCE IS
HIGHEST AND VCTS IN LOWER CONFIDENCE AREAS. MVFR OR LOWER CONDITIONS
ARE POSSIBLE IN TSRA.

CONVECTION SHOULD TAPER OFF AFTER 09-10Z...BUT LEFT VCSH IN TAFS
THROUGH DAYBREAK. AFTER TSRA LINE MOVES THROUGH...MVFR CONDITIONS
WILL DEVELOP.

MVFR CONDITIONS WILL CONTINUE THROUGH MID MORNING IN WAKE OF THE
LINE OF CONVECTION/COLD FRONT...AND CEILINGS WILL THEN IMPROVE TO
VFR CATEGORY BY LATE MORNING.  SOUTHWEST WINDS WILL PICK UP WITH
FRONTAL PASSAGE. SUSTAINED WIND SPEEDS WILL RANGE BETWEEN 12 TO 16
KTS WITH GUSTS TO 25 KTS. WINDS WILL VEER TO THE NORTHWEST AFTER THE
COLD FRONT PASSES AND WILL REMAIN BREEZY THROUGH LATE
AFTERNOON...BUT GUSTS WILL TAPER OFF BY MIDDAY.

&&

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

&&

SYNOPSIS...RYAN/JH
NEAR TERM...RYAN/JH
SHORT TERM...MK
LONG TERM....MK
AVIATION...TDUD/50

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
256 PM EDT SAT JUN 5 2010

INZ021-028>031-035>049-061000-
CARROLL-WARREN-TIPPECANOE-CLINTON-HOWARD-FOUNTAIN-MONTGOMERY-
BOONE-TIPTON-HAMILTON-MADISON-DELAWARE-RANDOLPH-VERMILLION-PARKE-
PUTNAM-HENDRICKS-MARION-HANCOCK-HENRY-
256 PM EDT SAT JUN 5 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL INDIANA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

THUNDERSTORMS ARE LIKELY THIS AFTERNOON AND TONIGHT. THERE IS A MODERATE
RISK THAT SOME OF THESE STORMS MAY BE SEVERE. THE MAIN THREATS
FROM ANY STORM THAT BECOMES SEVERE WILL BE LARGE HAIL AND DAMAGING
STRAIGHT LINE WINDS. HOWEVER AN ISOLATED TORNADO CANNOT BE RULED
OUT. SEVERE STORMS WILL BE MOST LIKELY DURING THE AFTERNOON AND
EVENING HOURS. LIGHTNING AND BRIEF HEAVY RAIN ARE THREATS FROM ANY
THUNDERSTORM.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY.

THERE IS A CHANCE FOR THUNDERSTORMS ON SUNDAY MORNING AS COLD
FRONT EXITS CENTRAL INDIANA. ANY STORMS ON SUNDAY MORNING ARE NOT
EXPECTED TO BE SEVERE. HOWEVER...LIGHTNING IS A THREAT WITH ANY THUNDERSTORM.

ADDITIONAL THUNDERSTORMS WILL BE POSSIBLE TUESDAY AND WEDNESDAY.
LIGHTNING IS A HAZARD IN ANY THUNDERSTORM.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS LIKELY THIS AFTERNOON AND EVENING.

&&

MORE INFORMATION...ALONG WITH OTHER WEATHER...HYDROLOGICAL AND
CLIMATE INFORMATION CAN BE FOUND...AT HTTP://WEATHER.GOV/IND (ALL
LOWERCASE)

INZ051>057-060>065-067>072-061000-
VIGO-CLAY-OWEN-MORGAN-JOHNSON-SHELBY-RUSH-SULLIVAN-GREENE-MONROE-
BROWN-BARTHOLOMEW-DECATUR-KNOX-DAVIESS-MARTIN-LAWRENCE-JACKSON-
JENNINGS-
256 PM EDT SAT JUN 5 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL INDIANA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

THUNDERSTORMS ARE LIKELY THIS AFTERNOON AND TONIGHT. THERE IS A SLIGHT RISK
THAT SOME OF THESE STORMS MAY BE SEVERE. THE MAIN THREATS FROM ANY
STORM THAT BECOMES SEVERE WILL BE LARGE HAIL AND DAMAGING STRAIGHT
LINE WINDS. HOWEVER AN ISOLATED TORNADO CANNOT BE RULED OUT.
SEVERE STORMS WILL BE MOST LIKELY DURING THE AFTERNOON AND EVENING
HOURS. LIGHTNING AND BRIEF HEAVY RAIN ARE THREATS FROM ANY
THUNDERSTORM.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY.

THERE IS A CHANCE FOR THUNDERSTORMS ON SUNDAY MORNING AS COLD
FRONT EXITS CENTRAL INDIANA. ANY STORMS ON SUNDAY MORNING ARE NOT
EXPECTED TO BE SEVERE. HOWEVER...LIGHTNING IS A THREAT WITH ANY THUNDERSTORM.

ADDITIONAL THUNDERSTORMS WILL BE POSSIBLE TUESDAY AND WEDNESDAY.
LIGHTNING IS A HAZARD IN ANY THUNDERSTORM.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS LIKELY THIS AFTERNOON AND EVENING.

&&

MORE INFORMATION...ALONG WITH OTHER WEATHER...HYDROLOGICAL AND
CLIMATE INFORMATION CAN BE FOUND...AT HTTP://WEATHER.GOV/IND (ALL
LOWERCASE)

KOCH/PUMA