Alert archive / Indiana / Severe Thunderstorm Watches in 2021

Severe Thunderstorm Watch 319

June 25, 202126 counties in Indiana

The Storm Prediction Center issued this severe thunderstorm watch at Jun 25, 2021, 7:47 PM EDT for 26 counties in Indiana. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued: Jun 25, 2021, 7:47 PM EDT (23:47 UTC)
Expired: Jun 26, 2021, 12:00 AM EDT
In force: 4 hr
Issued by: the Storm Prediction Center
Largest hail expected: 1.5 in
Strongest gust expected: 55 kt

All 26 counties

Benton County, IN, Carroll County, IN, Cass County, IN, Clinton County, IN, Elkhart County, IN, Fountain County, IN, Fulton County, IN, Howard County, IN, Jasper County, IN, Kosciusko County, IN, Lake County, IN, LaPorte County, IN, Marshall County, IN, Miami County, IN, Montgomery County, IN, Newton County, IN, Parke County, IN, Porter County, IN, Pulaski County, IN, Saint Joseph County, IN, Starke County, IN, Tippecanoe County, IN, Vermillion County, IN, Wabash County, IN, Warren County, IN, White County, IN

The radar

The Northern Indiana radar (KIWX), 107 km from the middle of the area, began a volume at 23:49 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: 20%
One or more EF2 to EF5 tornadoes: 5%
Ten or more severe wind reports: 30%
One or more gusts of 65 knots or more: 10%
Ten or more severe hail reports: 20%
One or more hailstones of 2 inches or more: 10%
Six or more combined severe hail and wind reports: 50%

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
Jun 25, 8:30 PM EDT	Tornado Warning	IND	Carroll	30 min
Jun 25, 8:53 PM EDT	Tornado Warning	IND	Carroll, Howard	37 min
Jun 25, 9:17 PM EDT	Tornado Warning	IWX	Cass	28 min
Jun 25, 9:24 PM EDT	Tornado Warning Tornado observed	IND	Carroll, Howard	21 min
Jun 25, 9:43 PM EDT	Tornado Warning	IWX	Cass	9 min
Jun 25, 10:37 PM EDT	Tornado Warning	IWX	Fulton, Pulaski	38 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

Lincoln, IL (KILX), launched 12:00Z, 11.8 hours before the alert went out and 172 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1244 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 113 m²/s²
0-3 km storm-relative helicity: 257 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted.

481 
WWUS20 KWNS 252343
SEL9  
SPC WW 252343
ILZ000-INZ000-260400-

URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 319
NWS Storm Prediction Center Norman OK
745 PM EDT Fri Jun 25 2021

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of 
  Northeast Illinois
  Northwest Indiana

* Effective this Friday night from 745 PM until Midnight EDT.

* Primary threats include...
  Isolated damaging wind gusts to 65 mph possible
  Isolated large hail events to 1.5 inches in diameter possible
  A tornado or two possible

SUMMARY...A few cells may develop into a cluster near the
Illinois-Indiana border before spreading towards north-central
Indiana through late evening.

The severe thunderstorm watch area is approximately along and 55
statute miles north and south of a line from 20 miles north of
Danville IL to 40 miles southeast of South Bend IN. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU9).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 314...WW 315...WW
316...WW 317...WW 318...

AVIATION...A few severe thunderstorms with hail surface and aloft to
1.5 inches. Extreme turbulence and surface wind gusts to 55 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector
25025.

...Grams

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 25, 1:57 PM EDT	Mesoscale Discussion	SPC	Brown, Clay, Crawford, Daviess, Dubois, Floyd and 17 more	2 hr
Jun 25, 5:48 PM EDT	Mesoscale Discussion	SPC	Hillsdale, Jackson, Lenawee, Livingston, Macomb, Monroe and 3 more	87 min

Nearby

Severe Thunderstorm Watches in Indiana, 2021 Every severe thunderstorm watch in 2021

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.