Tornadoes and Flash Flood in Indiana, April 14, 2006

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
122 AM EDT FRI APR 14 2006

.AVIATION...

SERIES OF FNTS CROSSING GRTLKS. PERIODS OF CONVECTION INTERSPERSED
WITH CAVOK. MVFR CIGS/VSYS WITH SOME WINDS G30 IN TSRA.

JK
&&

.PREVIOUS DISCUSSION...WEAK HIGH PRES OVR THE SERN SETS WHILE
DEVELOPING LOW PRES FOUND ACRS THE UPPER MIDWEST EARLY THIS
AFTERNOON. WEAK SOUTHERLY FLOW ACRS INDIANA WITH DEWPOINTS ONLY IN
THE UPPER 40S. DEWPOINTS THROUGH THE MIDDLE MISSISSIPPI VALLEY ARE
AROUND 50. SIXTY DEWPOINTS ARE FOUND ACRS TN AND FAR SOUTHERN MO.
VIS PIX SHOW ONLY A FEW CLOUDS OVR WI AND LM.

MAIN FORECAST CHALLENGE WL BE POPS THE NEXT SEVERAL DAYS.

MODELS AGREE ON ACTIVE WX PATTERN THE NEXT SEVERAL DAYS. NAM
DEVELOPS OVR IA/IL TONIGHT AND PUSHES THE SYSTEM SE ACRS INDIANA
OVERNIGHT. GFS HAS THIS FEATURE AS WELL BUT UPPER DYNAMICS ARE A BIT
SUSPECT. BOTH MODELS SHOW A FAVORABLE LLJ NEAR 40-50 KNTS. LOWER
LVL CONVERGENCE IS ALSO FAVORABLE AS SEEN THE H10-H8 Q VECTORS AND
TIME SECTIONS SHOW A BRIEF PERIOD OF MOIST COLUMN PUSHING ACRS THE
AREA. SOUNDINGS GO SOMEWHAT UNSTABLE BUT SATURATED OVERNIGHT.
MOISTURE REMAINS SUSPECT HOWEVER AS MODELS OVER FORECAST SFC
DEWPOINTS BY NEAR 5F IN SOME CASES. HENCE WITH A BIT OF CONFLICTING
INFORMATION TONIGHT WL STICK CLOSE TO ONGOING FORECAST OR PERHAPS
DROP POPS BY 10 PERCENT...ESPECIALLY ACRS THE SW WHERE WHERE
DYNAMICS AND CONVERGNCE WL BE WEAKER. WL USE A BLEND ON LOW TEMPS.

MODELS ON FRIDAY BRING ANOTHER ROUND OF MIXED SIGNALS FOR PCPN.
FORECAST SOUNDINGS SHOW IMPRESSIVE INSTABILITY AND CAPES BY FRI
AFTERNOON. NAM IS OVER 3K J/KG WITH LI/S NEAR -8. HOWEVER UPPER LVLS
SHOW LITTLE SUPPORT TO PROVIDE ANY KIND OF TRIGGER OTHER THAN
DAYTIME HEATING. UPPER LVLS SHOW WEAK RIDGE ACRS THE AREA. HOWEVER
WITH THE INSTABILITY AVAILABLE IS ANYTHING DOES DEVELOP IT MAY BE
QUITE STRONG...PRODUCING SEVERE WX. HENCE WL RAISE POPS SLIGHTLY TO
LOW CHC CATEGORY FOR PCPN CHCS TOMORROW AFTERNOON AND EARLY
EVENING. WITH H8 TEMPS EXPECTED A BIT HIGHER ON FRIDAY THAN TODAY WL
GO A BIT HIGHER THAN PERSISTENCE FOR HIGHS. WL USE A BLEND ON LOWS.

STRONGER UPPER RIDGE IN PLACE ON SATURDAY ACRS THE FA BUT AGAIN GOOD
INSTABILITY AVAILABLE ACCORDING TO THE FORECAST SOUNDINGS. DEEPER
TROUGH DEVELOPS OVR THE PLAINS STS ON SATURDAY AND THIS WL BE OUR
FORCING MECHANISM FOR SUNDAY. ATTM LIKE THE SITUATION FOR PCPN BEST
ON SUNDAY AS MORE ELEMENTS FOR PCPN COME TOGETHER. BUT FOR NOW WL
NEED TO CONTINUE LOW CHC POPS FOR SATURDAY IN CASE THINGS DO
DEVELOP UNDER TH RIDGE IN THE INSTABILITY. THINK AS WE GET A THROUGH
A DAY WITH THIS AIRMASS ON FRIDAY...WE SHOULD HAVE A BETTER HANDLE
OF WHAT TO EXPECT ON SATURDAY.  WL GO NEAR PERSISTENCE FOR HIGHS ON
SATURDAY AND STICK CLOSE TO MAV LOWS.

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

&&

KOCH/PUMA

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
344 PM EDT THU APR 13 2006

INZ021-028>031-035>049-051>057-062>065-072-141945-
CARROLL-WARREN-TIPPECANOE-CLINTON-HOWARD-FOUNTAIN-MONTGOMERY-
BOONE-TIPTON-HAMILTON-MADISON-DELAWARE-RANDOLPH-VERMILLION-PARKE-
PUTNAM-HENDRICKS-MARION-HANCOCK-HENRY-VIGO-CLAY-OWEN-MORGAN-
JOHNSON-SHELBY-RUSH-MONROE-BROWN-BARTHOLOMEW-DECATUR-JENNINGS-
344 PM EDT THU APR 13 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL INDIANA.

.DAY ONE...TONIGHT.

THUNDERSTORMS ARE LIKELY AFTER MIDNIGHT. ANY STORMS THAT DO
DEVELOP HAVE THE POTENTIAL TO BECOME STRONG TO SEVERE. THE RISK
OF SEVERE WEATHER OVERNIGHT IS MAINLY FROM THE INDIANAPOLIS AREA
AND NORTHWARD. THE MAIN THREAT FROM ANY STORMS WILL BE DAMAGING
STRAIGHT LINE WINDS AND LARGE HAIL.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

SCATTERED THUNDERSTORMS ARE POSSIBLE FRIDAY AFTERNOON...SATURDAY
AFTERNOON AND SUNDAY. ANY STORMS THAT DO DEVELOP HAVE THE
POTENTIAL TO BECOME SEVERE. THE MAIN THREAT FROM ANY STORMS OVER
THE WEEKEND WILL BE DAMAGING WINDS AND LARGE HAIL.

THUNDERSTORMS ARE POSSIBLE AGAIN ON TUESDAY NIGHT AND WEDNESDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED AFTER 1100 PM EDT. SPOTTERS MAY
ALSO BE NEEDED FRIDAY...SATURDAY AND SUNDAY.

&&

THIS PRODUCT IS NOW AVAILABLE IN GRAPHICAL FORMAT...ALONG WITH
OTHER WEATHER...HYDROLOGICAL AND CLIMATE INFORMATION...AT
HTTP://WEATHER.GOV/IND (ALL LOWERCASE)

INZ060-061-067>071-141945-
SULLIVAN-GREENE-KNOX-DAVIESS-MARTIN-LAWRENCE-JACKSON-
244 PM CDT THU APR 13 2006 /344 PM EDT THU APR 13 2006/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL INDIANA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

LOW LAND FLOODING WILL CONTINUE IN THE MOUNT CARMEL...PETERSBURG
AND HAZLETON AREAS THROUGH TONIGHT.

THUNDERSTORMS ARE POSSIBLE AFTER MIDNIGHT. ANY STORMS THAT DO
DEVELOP HAVE THE POTENTIAL TO BECOME STRONG TO SEVERE. THE MAIN
THREAT FROM ANY STORMS WILL BE DAMAGING STRAIGHT LINE WINDS AND
LARGE HAIL.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

SCATTERED THUNDERSTORMS ARE POSSIBLE FRIDAY AFTERNOON...SATURDAY
AFTERNOON AND SUNDAY. ANY STORMS THAT DO DEVELOP HAVE THE
POTENTIAL TO BECOME SEVERE. THE MAIN THREAT FROM ANY STORMS OVER
THE WEEKEND WILL BE DAMAGING WINDS AND LARGE HAIL.

THUNDERSTORMS ARE POSSIBLE AGAIN ON TUESDAY NIGHT AND WEDNESDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED AFTER 1100 PM. SPOTTERS MAY ALSO
BE NEEDED FRIDAY...SATURDAY AND SUNDAY.

&&

THIS PRODUCT IS NOW AVAILABLE IN GRAPHICAL FORMAT...ALONG WITH
OTHER WEATHER...HYDROLOGICAL AND CLIMATE INFORMATION...AT
HTTP://WEATHER.GOV/IND (ALL LOWERCASE)

PUMA