Alert archive / Indiana / Mesoscale Discussions in 2003

Mesoscale Discussion 515

April 20, 20038 states

The Storm Prediction Center issued this mesoscale discussion at Apr 20, 2003, 11:52 AM CDT for 8 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Apr 20, 2003, 11:52 AM CDT (16:52 UTC)
Expired
Apr 20, 2003, 2:15 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
All 186 counties

Arkansas County, AR, Bradley County, AR, Cleveland County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Lee County, AR, Lincoln County, AR, Mississippi County, AR, Monroe County, AR, Phillips County, AR, Poinsett County, AR, St. Francis County, AR, Union County, AR, Alexander County, IL, Clark County, IL, Clay County, IL, Coles County, IL, Crawford County, IL, Cumberland County, IL, Douglas County, IL, Edgar County, IL, Edwards County, IL, Effingham County, IL, Franklin County, IL, Gallatin County, IL, Hamilton County, IL, Hardin County, IL, Jasper County, IL, Jefferson County, IL, Johnson County, IL, Lawrence County, IL, Massac County, IL, Pope County, IL, Pulaski County, IL, Richland County, IL, Saline County, IL, Union County, IL, Vermilion County, IL, Wabash County, IL, Wayne County, IL, White County, IL, Williamson County, IL, Benton County, IN, Boone County, IN, Brown County, IN, Carroll County, IN, Cass County, IN, Clay County, IN, Clinton County, IN, Crawford County, IN, Daviess County, IN, DeKalb County, IN, Dubois County, IN, Elkhart County, IN, Fountain County, IN, Fulton County, IN, Gibson County, IN, Grant County, IN, Greene County, IN, Hamilton County, IN, Hancock County, IN, Hendricks County, IN, Howard County, IN, Huntington County, IN, Jackson County, IN, Jasper County, IN, Johnson County, IN, Knox County, IN, Kosciusko County, IN, LaGrange County, IN, Lake County, IN, LaPorte County, IN, Lawrence County, IN, Madison County, IN, Marion County, IN, Marshall County, IN, Martin County, IN, Miami County, IN, Monroe County, IN, Montgomery County, IN, Morgan County, IN, Newton County, IN, Noble County, IN, Orange County, IN, Owen County, IN, Parke County, IN, Perry County, IN, Pike County, IN, Porter County, IN, Posey County, IN, Pulaski County, IN, Putnam County, IN, Saint Joseph County, IN, Shelby County, IN, Spencer County, IN, Starke County, IN, Steuben County, IN, Sullivan County, IN, Tippecanoe County, IN, Tipton County, IN, Vanderburgh County, IN, Vermillion County, IN, Vigo County, IN, Wabash County, IN, Warren County, IN, Warrick County, IN, White County, IN, Whitley County, IN, Ballard County, KY, Caldwell County, KY, Calloway County, KY, Carlisle County, KY, Christian County, KY, Crittenden County, KY, Daviess County, KY, Fulton County, KY, Graves County, KY, Hancock County, KY, Henderson County, KY, Hickman County, KY, Hopkins County, KY, Livingston County, KY, Lyon County, KY, Marshall County, KY, McCracken County, KY, McLean County, KY, Muhlenberg County, KY, Ohio County, KY, Trigg County, KY, Union County, KY, Webster County, KY, Claiborne Parish, LA, De Soto Parish, LA, Dunklin County, MO, Mississippi County, MO, New Madrid County, MO, Pemiscot County, MO, Scott County, MO, Crockett County, TN, Dyer County, TN, Gibson County, TN, Haywood County, TN, Henry County, TN, Lake County, TN, Lauderdale County, TN, Obion County, TN, Shelby County, TN, Tipton County, TN, Weakley County, TN, Angelina County, TX, Aransas County, TX, Austin County, TX, Bee County, TX, Brooks County, TX, Calhoun County, TX, Colorado County, TX, DeWitt County, TX, Duval County, TX, Fayette County, TX, Fort Bend County, TX, Goliad County, TX, Gonzales County, TX, Grimes County, TX, Harris County, TX, Jackson County, TX, Jim Wells County, TX, Karnes County, TX, Kleberg County, TX, Lavaca County, TX, Live Oak County, TX, McMullen County, TX, Montgomery County, TX, Nueces County, TX, Polk County, TX, Refugio County, TX, San Jacinto County, TX, San Patricio County, TX, Shelby County, TX, Trinity County, TX, Victoria County, TX, Walker County, TX, Waller County, TX, Washington County, TX, Webb County, TX, Wharton County, TX

The watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Shreveport, LA (KSHV), launched 12:00Z, 4.9 hours before the alert went out and 126 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-pSkew-T log-p diagram, Shreveport, LA at 12:00Z on 2003-04-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 493 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Shreveport, LA at 12:00Z on 2003-04-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 170 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
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
493 J/kg
Mixed-layer CIN
-84 J/kg
Mixed-layer LCL
635 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
170 m²/s²
0-3 km storm-relative helicity
213 m²/s²
Significant tornado parameter
0.3
Supercell composite
1.1

Open this sounding in Storm Lab

The text

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

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 19, 7:54 PM CDTMesoscale DiscussionSPCPolk, Sebastian96 min
Apr 19, 8:55 PM CDTSevere Thunderstorm WatchSPCBenton, Crawford, Sebastian, Washington5 hr
Apr 19, 9:40 PM CDTMesoscale DiscussionSPCBaxter, Boone, Carroll, Franklin, Johnson, Madison and 3 more65 min
Apr 19, 10:35 PM CDTSevere Thunderstorm WatchSPCBaxter, Boone, Carroll, Franklin, Johnson, Madison and 5 more5 hr
Apr 19, 10:42 PM CDTMesoscale DiscussionSPCBenton, Crawford, Sebastian, Washington93 min
Apr 20, 1:25 AM CDTMesoscale DiscussionSPCBaxter, Boone, Clay, Cleburne, Craighead, Fulton and 13 more2 hr
Apr 20, 4:00 AM CDTMesoscale DiscussionSPCClay2 hr
Apr 20, 1:00 PM CDTMesoscale DiscussionSPCCrittenden, Lee, Mississippi3 hr
Apr 20, 3:02 PM CDTMesoscale DiscussionSPCAshley, Chicot, Desha, Drew3 hr
Apr 20, 1:50 AM CDTSevere Thunderstorm WatchSPCJackson, Monroe, Perry, Randolph, Washington5 hr
Apr 20, 12:20 PM CDTSevere Thunderstorm WatchSPCClark, Crawford, Edgar, Edwards, Hamilton, Jasper and 6 more6 hr
Apr 20, 1:45 PM CDTSevere Thunderstorm WatchSPCGallatin, Hardin, Johnson, Massac, Pope, Saline5 hr
Apr 20, 3:15 PM CDTSevere Thunderstorm WatchSPCDearborn, Franklin, Jefferson, Ohio, Ripley, Switzerland and 2 more6 hr
Apr 20, 4:35 PM CDTTornado WatchSPCClark, Crawford, Floyd, Harrison, Perry5 hr
Apr 20, 5:31 PM CDTMesoscale DiscussionSPCOhio, Switzerland89 min
Apr 20, 6:04 PM CDTMesoscale DiscussionSPCClark, Crawford, Floyd, Harrison116 min
Apr 20, 3:29 PM CDTMesoscale DiscussionSPCAdair, Allen, Anderson, Barren, Bath, Bourbon and 43 more2 hr
Apr 20, 6:25 PM CDTSevere Thunderstorm WatchSPCAllen, Barren, Calloway, Christian, Graves, Logan and 5 more6 hr
Apr 19, 8:29 PM CDTMesoscale DiscussionSPCBarton, Bates, Benton, Camden, Cass, Cedar and 15 more2 hr
Apr 20, 2:36 AM CDTMesoscale DiscussionSPCAtascosa, Bandera, Bee, Bexar, Dimmit, Frio and 11 more114 min
Apr 20, 9:20 AM CDTMesoscale DiscussionSPCHidalgo, Jim Hogg, Starr, Zapata2 hr

Nearby

Mesoscale Discussions in Indiana, 2003Mesoscale Discussions in Texas, 2003Mesoscale Discussions in Illinois, 2003Every mesoscale discussion in 2003

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.