Alert archive / Texas / Mesoscale Discussions in 2011
Mesoscale Discussion 492
The Storm Prediction Center issued this mesoscale discussion at Apr 20, 2011, 1:52 PM CDT for 27 counties in Texas. It was in force for 53 min.
The area
The outline as issued.
The facts
- Issued
- Apr 20, 2011, 1:52 PM CDT (18:52 UTC)
- Expired
- Apr 20, 2011, 2:45 PM CDT
- In force
- 53 min
- Issued by
- the Storm Prediction Center
All 27 counties
Bell County, TX, Bosque County, TX, Brown County, TX, Burnet County, TX, Coleman County, TX, Comanche County, TX, Concho County, TX, Coryell County, TX, Edwards County, TX, Falls County, TX, Gillespie County, TX, Hamilton County, TX, Hill County, TX, Kerr County, TX, Kimble County, TX, Lampasas County, TX, Llano County, TX, Mason County, TX, McCulloch County, TX, McLennan County, TX, Menard County, TX, Mills County, TX, Real County, TX, San Saba County, TX, Schleicher County, TX, Sutton County, TX, Tom Green County, TX
The radar
The San Angelo radar (KSJT), 143 km from the middle of the area, began a volume at 18:54 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
Del Rio, TX (KDRT), launched 12:00Z, 6.9 hours before the alert went out and 251 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
- 3836 J/kg
- Mixed-layer CIN
- -184 J/kg
- Mixed-layer LCL
- 1002 m above ground
- 0-6 km bulk shear
- 19 kt
- 0-1 km storm-relative helicity
- 144 m²/s²
- 0-3 km storm-relative helicity
- 131 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 5.3
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 |
|---|---|---|---|---|
| Apr 19, 7:47 PM CDT | Mesoscale Discussion | SPC | Bowie, Camp, Cass, Delta, Franklin, Hopkins and 11 more | 88 min |
| Apr 19, 9:03 PM CDT | Mesoscale Discussion | SPC | Bell, Coryell, Falls, Freestone, Henderson, Hill and 3 more | 57 min |
| Apr 19, 11:17 PM CDT | Mesoscale Discussion | SPC | Bowie, Camp, Cass, Franklin, Gregg, Harrison and 7 more | 58 min |
| Apr 19, 11:45 PM CDT | Severe Thunderstorm Watch | SPC | Bowie, Camp, Cass, Franklin, Gregg, Harrison and 6 more | 3 hr |
| Apr 20, 12:46 PM CDT | Mesoscale Discussion | SPC | Bowie, Camp, Cass, Franklin, Marion, Morris and 2 more | 89 min |
| Apr 20, 2:04 PM CDT | Severe Thunderstorm Watch | SPC | Bowie, Red River | 7 hr |
| Apr 20, 2:21 PM CDT | Severe Thunderstorm Watch | SPC | Bandera, Bell, Blanco, Burnet, Concho, Coryell and 20 more | 8 hr |
| Apr 20, 5:47 PM CDT | Mesoscale Discussion | SPC | Blanco, Burnet, Concho, Crockett, Edwards, Gillespie and 15 more | 58 min |
Nearby
Mesoscale Discussions in Texas, 2011Every mesoscale discussion in 2011
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.