Alert archive / Texas / Mesoscale Discussions in 2017
Mesoscale Discussion 798
The Storm Prediction Center issued this mesoscale discussion at May 20, 2017, 7:41 AM CDT for 27 counties in Texas. It was in force for 94 min.
The area
The outline as issued.
The facts
- Issued
- May 20, 2017, 7:41 AM CDT (12:41 UTC)
- Expired
- May 20, 2017, 9:15 AM CDT
- In force
- 94 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 40%
All 27 counties
Aransas County, TX, Atascosa County, TX, Bandera County, TX, Bee County, TX, Bexar County, TX, Caldwell County, TX, Calhoun County, TX, Comal County, TX, DeWitt County, TX, Frio County, TX, Goliad County, TX, Gonzales County, TX, Guadalupe County, TX, Hays County, TX, Jackson County, TX, Karnes County, TX, Kendall County, TX, Lavaca County, TX, Live Oak County, TX, McMullen County, TX, Medina County, TX, Nueces County, TX, Refugio County, TX, San Patricio County, TX, Uvalde County, TX, Victoria County, TX, Wilson County, TX
The radar
The Austin/San Antonio radar (KEWX), 71 km from the middle of the area, began a volume at 12:44 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 watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Corpus Christi, TX (KCRP), launched 12:00Z, 0.7 hours before the alert went out and 180 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
- 2452 J/kg
- Mixed-layer CIN
- -31 J/kg
- Mixed-layer LCL
- 634 m above ground
- 0-6 km bulk shear
- 44 kt
- 0-1 km storm-relative helicity
- 88 m²/s²
- 0-3 km storm-relative helicity
- 153 m²/s²
- Significant tornado parameter
- 1.7
- Supercell composite
- 8.8
The text
As transmitted.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 19, 7:15 PM CDT | Mesoscale Discussion | SPC | Brown, Callahan, Coke, Coleman, Concho, Fisher and 11 more | 60 min |
| May 19, 7:44 PM CDT | Tornado Watch | SPC | Brown, Callahan, Coke, Coleman, Concho, Fisher and 15 more | 7 hr |
| May 19, 11:05 PM CDT | Mesoscale Discussion | SPC | Brown, Callahan, Coke, Coleman, Comanche, Concho and 14 more | 115 min |
| May 20, 10:15 AM CDT | Severe Thunderstorm Watch | SPC | Atascosa, Bee, Bexar, DeWitt, Dimmit, Duval and 18 more | 11 hr |
| May 20, 12:56 PM CDT | Mesoscale Discussion | SPC | Atascosa, Bee, Bexar, DeWitt, Dimmit, Frio and 13 more | 94 min |
| May 20, 3:46 PM CDT | Mesoscale Discussion | SPC | Atascosa, Bee, Bexar, DeWitt, Dimmit, Duval and 19 more | 59 min |
Nearby
Mesoscale Discussions in Texas, 2017Every mesoscale discussion in 2017
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.