Alert archive / Texas / Mesoscale Discussions in 2012
Mesoscale Discussion 1520
The Storm Prediction Center issued this mesoscale discussion at Jul 20, 2012, 3:45 PM CDT for 4 states. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 20, 2012, 3:45 PM CDT (20:45 UTC)
- Expired
- Jul 20, 2012, 6:15 PM CDT
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 5%
All 85 counties
Hempstead County, AR, Howard County, AR, Lafayette County, AR, Little River County, AR, Miller County, AR, Nevada County, AR, Pike County, AR, Sevier County, AR, Caddo Parish, LA, Atoka County, OK, Beckham County, OK, Bryan County, OK, Caddo County, OK, Carter County, OK, Choctaw County, OK, Coal County, OK, Comanche County, OK, Cotton County, OK, Custer County, OK, Dewey County, OK, Ellis County, OK, Garvin County, OK, Grady County, OK, Greer County, OK, Harmon County, OK, Jackson County, OK, Jefferson County, OK, Johnston County, OK, Kiowa County, OK, Love County, OK, Marshall County, OK, McClain County, OK, McCurtain County, OK, Murray County, OK, Pontotoc County, OK, Pushmataha County, OK, Roger Mills County, OK, Stephens County, OK, Tillman County, OK, Washita County, OK, Archer County, TX, Baylor County, TX, Bowie County, TX, Camp County, TX, Cass County, TX, Clay County, TX, Collin County, TX, Cooke County, TX, Dallas County, TX, Delta County, TX, Denton County, TX, Ellis County, TX, Fannin County, TX, Franklin County, TX, Grayson County, TX, Gregg County, TX, Hardeman County, TX, Harrison County, TX, Hemphill County, TX, Henderson County, TX, Hopkins County, TX, Hunt County, TX, Jack County, TX, Kaufman County, TX, Lamar County, TX, Marion County, TX, Montague County, TX, Morris County, TX, Palo Pinto County, TX, Parker County, TX, Rains County, TX, Red River County, TX, Rockwall County, TX, Smith County, TX, Tarrant County, TX, Throckmorton County, TX, Titus County, TX, Upshur County, TX, Van Zandt County, TX, Wheeler County, TX, Wichita County, TX, Wilbarger County, TX, Wise County, TX, Wood County, TX, Young County, TX
The radar
The Norman radar (KTLX), 159 km from the middle of the area, began a volume at 20:46 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.
The nearest sounding before it
Fort Worth, TX (KFWD), launched 12:00Z, 8.8 hours before the alert went out and 140 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.
- Mixed-layer CAPE
- 1010 J/kg
- Mixed-layer CIN
- -172 J/kg
- Mixed-layer LCL
- 1582 m above ground
- 0-6 km bulk shear
- 7 kt
- 0-1 km storm-relative helicity
- 19 m²/s²
- 0-3 km storm-relative helicity
- 88 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.7
The text
As transmitted, in the capitals the NWS used until 2016.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 20, 12:47 PM CDT | Mesoscale Discussion | SPC | Ashley, Chicot, Union | 2 hr |
| Jul 20, 3:03 PM CDT | Mesoscale Discussion | SPC | Acadia, Allen, Ascension, Assumption, Calcasieu, Cameron and 7 more | 2 hr |
Nearby
Mesoscale Discussions in Texas, 2012Mesoscale Discussions in Oklahoma, 2012Mesoscale Discussions in Arkansas, 2012Every mesoscale discussion 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.