Special Weather Statement, NWS Indianapolis, IN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
422 PM EDT MON AUG 20 2012

.UPDATE...

THE AVIATION SECTION HAS BEEN UPDATED BELOW.

&&

.SYNOPSIS...
ISSUED AT 347 PM EDT MON AUG 20 2012

UPPER TROUGHING OVER THE REGION WILL GRADUALLY DEPART TONIGHT INTO
EARLY TOMORROW...AND RIDGING AT THE SURFACE WILL REASSERT
DOMINANCE FOR MUCH OF THE REMAINDER OF THE FORECAST PERIOD...WITH
WEAK QUASI ZONAL FLOW ALOFT BECOMING MORE ANTICYCLONIC LATER IN
THE WEEK. TEMPERATURES WILL GRADUALLY WARM BACK TO NEAR OR JUST
ABOVE NORMAL VALUES THIS WEEK.

&&

.NEAR TERM /TONIGHT/...
ISSUED AT 347 PM EDT MON AUG 20 2012

FOCUS IS ON ENDING OF THUNDERSTORMS. GUIDANCE IS SIMILAR AND A
BLEND IS USED.

ISOLATED THUNDERSTORMS ARE DEVELOPING...BUT STRUGGLING IN A WEAKLY
FORCED ENVIRONMENT. ONLY THUNDERSTORMS OVER NORTHEAST ILLINOIS AND
NORTHWEST INDIANA...AIDED IN PART BY CONVERGENCE ALONG THE LAKE
BREEZE...ARE MAINTAINING ANY KIND OF SIGNIFICANT COVERAGE. THESE
MAY MANAGE TO PERSIST TO NEAR 00Z...BUT EXPECT THAT MOST ALL
CONVECTION WILL BE DONE BY THE START OF THE OVERNIGHT PERIOD...SO
WILL CARRY NO POPS AFTER 00Z.

ON TEMPS...PREFER NUMBERS JUST ABOVE CONSENSUS...NEAR
PERSISTENCE...AS THERE HAS BEEN LITTLE CHANGE IN THE AIRMASS FROM
YESTERDAY/LAST NIGHT. THIS AGREES FAIRLY WELL WITH LOW LEVEL
THICKNESSES...YIELDING LOW TO MID 50S AGAIN TONIGHT.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY/...
ISSUED AT 347 PM EDT MON AUG 20 2012

FOCUS IS MAINLY TEMPS THROUGHOUT AS HIGH PRESSURE REASSERTS
ITSELF. GUIDANCE IS SIMILAR AND A BLEND IS USED.

GUIDANCE SUGGESTS ONE FINAL WEAK WAVE MAY BE DEPARTING THE AREA
EARLY TOMORROW...BUT AS IT SHOULD BE GONE BY PEAK HEATING...EXPECT
NO CONVECTIVE DEVELOPMENT OVER THE AREA BEYOND CUMULUS...AND WILL
KEEP DRY FORECAST. AS SURFACE HIGH BUILDS IN...THIS WILL CONTINUE
THROUGH THE REMAINDER OF THE SHORT TERM.

ON TEMPS...LOW LEVEL THICKNESSES RISE GRADUALLY THROUGHOUT THE
SHORT TERM...AND A STEADY WARMING TREND IS DEPICTED. NEAR TO JUST
ABOVE CONSENSUS NUMBERS DEPICT THIS WELL AND THIS WAS THE GENERAL
MAX/MIN TEMP TECHNIQUE.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
ISSUED AT 142 PM EDT MON AUG 20 2012

FOCUS FOR THE EXTENDED WILL BE TEMPERATURES AND WHETHER OR NOT TO
MENTION ANY POPS.

MODELS IN GOOD AGREEMENT ON SOUTH AND SOUTHWEST LOW LEVEL FLOW AS
SURFACE HIGH PRESSURE BECOMES ANCHORED ACROSS THE EASTERN STATES.
THE RESULT WILL BE SLIGHTLY ABOVE NORMAL TEMPERATURES AND INCREASING
HUMIDITY. HOWEVER...THE MAIN COLD FRONT SHOULD BE FAR ENOUGH TO THE
NORTHWEST MONDAY TO BE A FACTOR...AND WITH DEEP MOISTURE
ABSENT...WILL HOLD OFF ON POPS AT THIS TIME...EVEN THOUGH LOW
COVERAGE THUNDERSTORMS WOULD NOT BE OUT OF THE REALM OF POSSIBILITY.
FELT THE CENTRAL REGIONAL INITIALIZATION TEMPERATURES LOOKED FINE.

&&

.AVIATION /DISCUSSION FOR THE 202100Z KIND TAF UPDATE/...

ISSUED AT 421 PM EDT MON AUG 20 2012

SCATTERED CONVECTION CURRENTLY ACROSS NORTHERN INDIANA INTO EASTERN
ILLINOIS...ASSOCIATED WITH AN UPPER WAVE DROPPING SOUTHEAST THROUGH
THE MIDWEST. DOESN/T APPEAR THERE IS AN IMMINENT THREAT OF
CONVECTION IN THE VICINITY OF KIND...HOWEVER SHORT TERM MODELS BRING
AN INCREASED AREA OF LIFT OVER KIND OVER THE NEXT FEW HOURS. AIR
MASS IS WEAKLY UNSTABLE...SO THREAT OF CONVECTION OVER KIND WILL
CONTINUE INTO THE EVENING HOURS. PREVIOUS DISCUSSION FOLLOWS.

UPPER ENERGY WILL DROP FROM THE UPPER MIDWEST TO ILLINOIS LATE TODAY
AND INTERACT WITH A SLIGHTLY UNSTABLE ATMOSPHERE AND IS EXPECTED TO
RESULT IN ISOLATED TO SCATTERED THUNDERSTORMS ACROSS CENTRAL
INDIANA. RAPID REFRESH AND CONVECTIVE TEMPERATURES SUGGEST A 20Z
INITIATION. THE STORMS SHOULD THEN END BY 00Z. WITH COVERAGE
LOW...ONLY WENT WITH VCTS FROM 20Z-00Z. OTHERWISE...VFR CONDITIONS
AND WINDS LESS THAN 10 KNOTS THROUGH TUESDAY. DO NOT EXPECT MUCH IF
ANY FOG TONIGHT WITH DEW POINTS ONLY IN THE LOWER 50S.
HOWEVER...WOULD NOT COMPLETELY RULE OUT BRIEF MVFR OR IFR TOWARDS
DAWN.

&&

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

&&

SYNOPSIS...NIELD
NEAR TERM...NIELD
SHORT TERM...NIELD
LONG TERM....PUMA
AVIATION...MK/JAS

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
409 PM EDT MON AUG 20 2012

INZ021-028>031-035>049-051>057-060>065-067>072-211000-
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-
409 PM EDT MON AUG 20 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL INDIANA.

.DAY ONE...TONIGHT.

OUTLOOK: ISOLATED THUNDERSTORMS.

HAZARDS: THUNDERSTORMS PRODUCING LIGHTNING...GUSTY WINDS AND SMALL HAIL.

TIMING: THROUGH 8 PM.

DISCUSSION: A WEAK DISTURBANCE COMBINED WITH DAYTIME HEATING WILL
PRODUCE ISOLATED THUNDERSTORMS THIS AFTERNOON AND EARLY EVENING.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY.

OUTLOOK: NO SIGNIFICANT WEATHER IS EXPECTED.

DISCUSSION: HIGH PRESSURE TO THE SOUTHEAST WILL KEEP CENTRAL INDIANA
DRY INTO THE WEEKEND.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED.

&&

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

RYAN

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
502 PM EDT MON AUG 20 2012

INZ029-202130-
TIPPECANOE-
502 PM EDT MON AUG 20 2012

...STRONG THUNDERSTORM ADVISORY FOR CENTRAL TIPPECANOE COUNTY UNTIL
530 PM EDT...

AT 458 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM NEAR LAFAYETTE...MOVING EAST AT 5 MPH.

HAIL UP TO THE SIZE OF PENNIES AND WIND GUSTS UP TO 40 MPH ARE
EXPECTED WITH THIS STORM.

LOCATIONS NEAR THE PATH OF THIS STORM INCLUDE...
  LAFAYETTE...
  DAYTON...

IF THREATENING WEATHER APPROACHES YOUR AREA...TAKE SHELTER IN A
STURDY BUILDING.

&&

LAT...LON 4043 8670 4028 8676 4035 8702 4046 8696
TIME...MOT...LOC 2103Z 284DEG 5KT 4039 8689

RYAN