Alert archive / Texas / Mesoscale Discussions in 2004

Mesoscale Discussion 2064

August 20, 200425 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Aug 20, 2004, 6:25 PM CDT for 25 counties in Texas. It was in force for 95 min.

The area

The outline as issued.

The facts

Issued: Aug 20, 2004, 6:25 PM CDT (23:25 UTC)
Expired: Aug 20, 2004, 8:00 PM CDT
In force: 95 min
Issued by: the Storm Prediction Center

All 25 counties

Bandera County, TX, Concho County, TX, Crane County, TX, Crockett County, TX, Ector County, TX, Edwards County, TX, Gillespie County, TX, Glasscock County, TX, Irion County, TX, Kerr County, TX, Kimble County, TX, Mason County, TX, McCulloch County, TX, Medina County, TX, Menard County, TX, Midland County, TX, Reagan County, TX, Real County, TX, Schleicher County, TX, Sutton County, TX, Terrell County, TX, Tom Green County, TX, Upton County, TX, Uvalde County, TX, Val Verde County, TX

The radar

The San Angelo radar (KSJT), 109 km from the middle of the area, began a volume at 23:24 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

Del Rio, TX (KDRT), launched 12:00Z, 11.4 hours before the alert went out and 134 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: 2156 J/kg
Mixed-layer CIN: -172 J/kg
Mixed-layer LCL: 1135 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 110 m²/s²
0-3 km storm-relative helicity: 126 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.0

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.

Issued	Product	Office	Counties	Lasted
Aug 20, 1:27 AM CDT	Mesoscale Discussion	SPC	Borden, Cottle, Crosby, Dawson, Dickens, Fisher and 16 more	93 min
Aug 20, 3:02 PM CDT	Mesoscale Discussion	SPC	Bastrop, Bell, Blanco, Brazos, Burleson, Burnet and 29 more	2 hr
Aug 20, 3:40 PM CDT	Severe Thunderstorm Watch	SPC	Bandera, Concho, Crane, Crockett, Ector, Edwards and 20 more	6 hr

Nearby

Mesoscale Discussions in Texas, 2004 Every mesoscale discussion in 2004

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.