Alert archive / Indiana / Severe Thunderstorm Watches in 2012

Severe Thunderstorm Watch 562

August 5, 201222 counties in Indiana; 15 counties in Ohio

The Storm Prediction Center issued this severe thunderstorm watch at Aug 5, 2012, 5:29 AM EDT for 22 counties in Indiana; 15 counties in Ohio. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued: Aug 5, 2012, 5:29 AM EDT (09:29 UTC)
Expired: Aug 5, 2012, 8:25 AM EDT
In force: 3 hr
Issued by: the Storm Prediction Center
Largest hail expected: 1.5 in
Strongest gust expected: 60 kt

All 37 counties

Blackford County, IN, Decatur County, IN, Delaware County, IN, Fayette County, IN, Franklin County, IN, Grant County, IN, Hamilton County, IN, Hancock County, IN, Hendricks County, IN, Henry County, IN, Howard County, IN, Jay County, IN, Johnson County, IN, Madison County, IN, Marion County, IN, Morgan County, IN, Randolph County, IN, Rush County, IN, Shelby County, IN, Tipton County, IN, Union County, IN, Wayne County, IN, Auglaize County, OH, Butler County, OH, Champaign County, OH, Clark County, OH, Clinton County, OH, Darke County, OH, Greene County, OH, Hardin County, OH, Logan County, OH, Mercer County, OH, Miami County, OH, Montgomery County, OH, Preble County, OH, Shelby County, OH, Warren County, OH

The radar

The Indianapolis radar (KIND), 94 km from the middle of the area, began a volume at 09:32 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes: 10%
One or more EF2 to EF5 tornadoes: 5%
Ten or more severe wind reports: 40%
One or more gusts of 65 knots or more: 20%
Ten or more severe hail reports: 20%
One or more hailstones of 2 inches or more: 5%
Six or more combined severe hail and wind reports: 60%

Warnings issued inside it

2 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

Issued	Product	Office	Counties	Lasted
Aug 5, 6:32 AM EDT	Severe Thunderstorm Warning	IND	Henry, Rush	28 min
Aug 5, 6:37 AM EDT	Severe Thunderstorm Warning	ILN	Auglaize, Hardin, Logan, Shelby	42 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Cncnati-Daytn, OH (KILN), launched 00:00Z, 9.5 hours before the alert went out and 144 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 3062 J/kg
Mixed-layer CIN: -5 J/kg
Mixed-layer LCL: 842 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: 124 m²/s²
0-3 km storm-relative helicity: 135 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

882 
WWUS20 KWNS 050933
SEL2
SPC WW 050933
INZ000-OHZ000-051600-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 562
NWS STORM PREDICTION CENTER NORMAN OK
530 AM EDT SUN AUG 5 2012

THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

       CENTRAL AND EAST CENTRAL INDIANA
       WEST CENTRAL AND SOUTHWEST OHIO

EFFECTIVE THIS SUNDAY MORNING FROM 530 AM UNTIL NOON EDT.

HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 50
STATUTE MILES NORTH AND SOUTH OF A LINE FROM 20 MILES NORTHWEST
OF INDIANAPOLIS INDIANA TO 45 MILES EAST OF DAYTON OHIO.  FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU2).

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.

DISCUSSION...LINE OF STORMS MOVING INTO CENTRAL INDIANA HAS BECOME
BETTER ORGANIZED AND IS SHOWING SIGNS OF DEVELOPING INTO A BOW ECHO
SYSTEM AS IT MOVES EWD 35 KT.  RADAR IS INDICATING A SERIES OF
MESOVORTICES ALONG THE LEADING EDGE OF THE SYSTEM SUGGESTING
POTENTIAL FOR SMALL SWATHS OF DAMAGING WINDS.  SYSTEM MAY BEGIN TO
ACCELERATE EWD ALONG A REMNANT OUTFLOW BOUNDARY...AND IF THIS OCCURS
THERE WILL BE INCREASING LIKELIHOOD OF STRONG/SEVERE WIND GUSTS
SPREADING EWD INTO OH.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
MOTION VECTOR 27035.


...WEISS

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 5, 4:57 AM EDT	Mesoscale Discussion	SPC	Blackford, Delaware, Fayette, Franklin, Grant, Hamilton and 12 more	2 hr
Aug 4, 10:46 PM EDT	Mesoscale Discussion	SPC	Ashland, Ashtabula, Carroll, Champaign, Clark, Columbiana and 35 more	119 min
Aug 5, 7:57 AM EDT	Mesoscale Discussion	SPC	Champaign, Clark, Clinton, Delaware, Fayette, Franklin and 5 more	63 min

Nearby

Severe Thunderstorm Watches in Indiana, 2012 Severe Thunderstorm Watches in Ohio, 2012 Every severe thunderstorm watch in 2012

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.