Flooding and Hail in Indiana, June 23, 2013

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
238 PM EDT SUN JUN 23 2013

.UPDATE...
THE SYNOPSIS...NEAR TERM AND SHORT TERM SECTIONS HAVE BEEN UPDATED BELOW.

&&

.SYNOPSIS...
ISSUED AT 234 PM EDT SUN JUN 23 2013

OCCASIONAL UPPER LEVEL WEATHER DISTURBANCES MAY AFFECT THE AREA INTO
THE MIDDLE OF WEEK. A COLD FRONT IS EXPECTED TO MOVE THROUGH AROUND
THURSDAY OR FRIDAY. IN THE WAKE OF THIS FRONT...HIGH PRESSURE WILL
BUILD INTO THE AREA BY NEXT WEEKEND.

&&

.NEAR TERM /REST OF THIS AFTERNOON AND TONIGHT/...
ISSUED AT 234 PM EDT SUN JUN 23 2013

SCATTERED CONVECTION EXPECTED TO CONTINUE FOR THE REST OF THE
AFTERNOON ASSOCIATED WITH A WEAK UPPER LOW...MODERATELY UNSTABLE AIR
MASS...AND LITTLE CAP. MOST OF THE ACTIVITY SHOULD DIMINISH AFTER
SUNSET...HOWEVER THERE IS POTENTIAL FOR ADDITIONAL CONVECTION LATER
TONIGHT AS A REMNANT MVC FROM DISSIPATING COMPLEX OVER EASTERN
IOWA/MISSOURI MOVES INTO THE AREA. FOR THAT REASON...WILL KEEP
CHANCE POPS GOING THROUGHOUT THE TONIGHT PERIOD. HEAVY RAIN IS
POSSIBLE WITH PRECIPITABLE WATERS AROUND 1.75 INCHES.

GFS MOS LOWS TONIGHT LOOK REASONABLE BASED ON LOW LEVEL THICKNESSES.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
ISSUED AT 234 PM EDT SUN JUN 23 2013

MODEL DATA SUGGEST THE LOCAL AREA WILL REMAIN ON THE PERIPHERY OF AN
UPPER RIDGE THAT WILL GRADUALLY SHIFT WESTWARD TOWARDS THE SOUTHERN
ROCKIES BY THE MIDDLE OF THE WEEK. THIS WILL GRADUALLY VEER THE
UPPER FLOW TO A MORE NORTHWEST DIRECTION WITH TIME...BUT LITTLE IN
THE WAY OF LOWERING HEIGHTS/THICKNESSES EXPECTED DURING THIS PERIOD.
AS A RESULT...THERE WILL BE A CONTINUED THREAT FOR POTENTIAL MCS
ACTIVITY INTO THE MIDDLE OF THE WEEK AS STEEPER LAPSE RATES ADVECT
INTO THE AREA. MODEL DATA SEEM TO SUGGEST THE BEST THREAT FOR
CONVECTION WILL BE ON MONDAY AND WEDNESDAY...HOWEVER CONFIDENCE IN
LOCATION AND TIMING OF THESE POTENTIAL SYSTEMS AT THIS POINT IS LOW.
FOR NOW...WILL BROADBRUSH CHANCE POPS ALL PERIODS.

BASED ON PROGGED LOW LEVEL THICKNESSES...THE GFS MOS TEMPERATURE
GUIDANCE LOOKS PRETTY GOOD...SO WILL NOT STRAY TOO MUCH FROM THEM.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...

ISSUED AT 219 PM EDT SUN JUN 23 2013

ECMWF AND GFS DEPICT A WARM AND MOIST PATTERN CONTINUING THROUGH
THE WORK WEEK BEFORE A COLD FRONT AND AREA OF HIGH PRESSURE
ARRIVES ON SATURDAY AND SUNDAY.

WEDNESDAY NIGHT THROUGH FRIDAY...A DEEP TROUGH REMAINS ALOFT AS AN
AREA OF LOW PRESSURE BEGINS TO PUSH SOUTHEAST OUT OF CANADA.
MEANWHILE A WARM AND MOIST AIR MASS WILL REMAIN IN PLACE ACROSS
THE AREA AS WARM SOUTHERLY WINDS PROVIDE HUMID GULF AIR. THUS WILL
CONTINUE CHANCES FOR TSRA THROUGH SATURDAY AS THIS PATTERN
PERSISTS. A RIDGE OF HIGH PRESSURE AND A SURFACE HIGH PRESSURE
BUILDS ACROSS THE AREA ON SATURDAY NIGHT AND SUNDAY...FINALLY
BRINGING THE PRECIP CHANCES TO AND END AS LESS HUMID AIR ARRIVES ON
NORTHERLY WINDS.

&&

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

ISSUED AT 1233 PM EDT SUN JUN 23 2013

MAINLY VFR THIS PERIOD...ALTHOUGH MVFR TO IFR CONDITIONS WILL BE
POSSIBLE WITH ANY TSRA THAT STRIKES A TAF SITES...AS WELL AS MVFR
FOG PRIOR TO SUNRISE ON MONDAY.

USED A PERSISTENCE TYPE FORECAST DURING THIS PERIOD AS LITTLE
CHANGE IN AIR MASS AND OVERALL WEATHER PATTERN IS EXPECTED.
FORECAST SOUNDINGS CONTINUE TO INDICATE EASILY ATTAINABLE
CONVECTIVE TEMPERATURES AND A WARM AND MOIST AIR MASS IN PLACE.
THUS WILL CONTINUE THE DAILY VCTS MENTION DURING THE PEAK HEATING
HOURS AS WELL AS MVFR DURING PEAK COOLING HOURS.

&&

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

SYNOPSIS...JAS
NEAR TERM...JAS
SHORT TERM...JAS
LONG TERM....PUMA
AVIATION...JP

VISIT US AT HTTP://WWW.WEATHER.GOV/IND

FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
427 AM EDT SUN JUN 23 2013

INZ021-028>031-035>049-051>057-060>065-067>072-240830-
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-SULLIVAN-GREENE-MONROE-BROWN-BARTHOLOMEW-
DECATUR-KNOX-DAVIESS-MARTIN-LAWRENCE-JACKSON-JENNINGS-
427 AM EDT SUN JUN 23 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL INDIANA.

.DAY ONE...TODAY AND TONIGHT.

OUTLOOK: CHANCE OF THUNDERSTORMS.

HAZARDS: LIGHTNING...HEAVY RAIN...GUSTY WINDS AND SMALL HAIL.

TIMING: THIS AFTERNOON AND EVENING.

DISCUSSION: A WARM AND MOIST AIRMASS REMAINS IN PLACE ACROSS
CENTRAL INDIANA. THIS MAY LEAD TO SOME SHOWERS AND THUNDERSTORMS
THIS AFTERNOON AND EVENING. WIDESPREAD SEVERE STORMS ARE NOT
EXPECTED...ALTHOUGH SLOW MOVING STORMS COULD PRODUCE VERY HEAVY
RAIN AND FLOODING IN ISOLATED AREAS.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.

OUTLOOK: THUNDERSTORMS ARE POSSIBLE ACROSS CENTRAL INDIANA AT
TIMES FROM MONDAY THROUGH SATURDAY. AT THIS POINT...WIDESPREAD
SEVERE STORMS ARE NOT EXPECTED. LIGHTNING IS A THREAT FROM ANY
THUNDERSTORM. WARM TEMPERATURES AND HIGH HUMIDITY COULD PRODUCE
HEAT INDEX VALUES IN THE UPPER 90S TO NEAR 100 DEGREES AT TIMES
THIS WEEK...ESPECIALLY TUESDAY AND WEDNESDAY.

DISCUSSION: A HUMID AND UNSTABLE AIRMASS WILL BE IN PLACE
THROUGHOUT THE WEEK...WITH SEVERAL CHANCES FOR SHOWERS AND
THUNDERSTORMS...AND VERY WARM CONDITIONS AT TIMES.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS ARE ENCOURAGED TO REPORT HEAVY RAINFALL AND FLOODING AS A
RESULT OF SLOW MOVING THUNDERSTORMS...AS WELL AS ANY OTHER
PHENOMENA OBSERVED WITH THE STORMS.

&&

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

NIELD