Alert archive / Texas / Mesoscale Discussions in 2009

Mesoscale Discussion 490

April 16, 200940 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 16, 2009, 8:36 PM CDT for 40 counties in Texas. It was in force for 84 min.

The area

The outline as issued.

The facts

Issued: Apr 16, 2009, 8:36 PM CDT (01:36 UTC)
Expired: Apr 16, 2009, 10:00 PM CDT
In force: 84 min
Issued by: the Storm Prediction Center

All 40 counties

Andrews County, TX, Borden County, TX, Briscoe County, TX, Castro County, TX, Childress County, TX, Coke County, TX, Cottle County, TX, Crane County, TX, Crosby County, TX, Dawson County, TX, Dickens County, TX, Ector County, TX, Fisher County, TX, Floyd County, TX, Gaines County, TX, Garza County, TX, Glasscock County, TX, Hale County, TX, Hall County, TX, Hockley County, TX, Howard County, TX, Irion County, TX, Kent County, TX, King County, TX, Lamb County, TX, Lubbock County, TX, Lynn County, TX, Martin County, TX, Midland County, TX, Mitchell County, TX, Motley County, TX, Nolan County, TX, Reagan County, TX, Scurry County, TX, Sterling County, TX, Stonewall County, TX, Swisher County, TX, Terry County, TX, Tom Green County, TX, Upton County, TX

The radar

The Midland/Odessa radar (KMAF), 80 km from the middle of the area, began a volume at 01:36 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.

Severe Thunderstorm Watch 158Apr 16, 11:35 PM CDT

The nearest sounding before it

Midland Regional, TX (KMAF), launched 00:00Z, 1.6 hours before the alert went out and 81 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: 404 J/kg
Mixed-layer CIN: -64 J/kg
Mixed-layer LCL: 2611 m above ground
0-6 km bulk shear: 59 kt
0-1 km storm-relative helicity: 94 m²/s²
0-3 km storm-relative helicity: 236 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 3.8

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
Apr 16, 7:31 PM CDT	Mesoscale Discussion	SPC	Brewster, Kinney, Pecos, Terrell, Val Verde	89 min
Apr 16, 7:43 PM CDT	Mesoscale Discussion	SPC	Anderson, Angelina, Cherokee, Dallas, Ellis, Freestone and 23 more	62 min
Apr 16, 9:20 PM CDT	Mesoscale Discussion	SPC	Armstrong, Carson, Collingsworth, Dallam, Deaf Smith, Donley and 14 more	55 min
Apr 16, 10:56 PM CDT	Mesoscale Discussion	SPC	Coke, Concho, Crockett, Fisher, Irion, Jones and 11 more	94 min
Apr 16, 11:35 PM CDT	Severe Thunderstorm Watch	SPC	Bandera, Brown, Callahan, Coleman, Comanche, Concho and 26 more	6 hr
Apr 17, 2:32 AM CDT	Mesoscale Discussion	SPC	Brown, Callahan, Coleman, Comanche, Concho, Eastland and 20 more	118 min
Apr 17, 5:16 AM CDT	Mesoscale Discussion	SPC	Blanco, Burnet, Edwards, Gillespie, Kendall, Kerr and 8 more	59 min
Apr 17, 7:28 AM CDT	Mesoscale Discussion	SPC	Atascosa, Bandera, Bastrop, Bell, Bexar, Blanco and 23 more	92 min
Apr 17, 7:48 AM CDT	Severe Thunderstorm Watch	SPC	Atascosa, Bandera, Bastrop, Bell, Bexar, Blanco and 35 more	5 hr
Apr 17, 9:56 AM CDT	Mesoscale Discussion	SPC	Anderson, Angelina, Atascosa, Austin, Bastrop, Bee and 63 more	94 min
Apr 17, 10:24 AM CDT	Tornado Watch	SPC	Austin, Brazoria, Brazos, Burleson, Chambers, Colorado and 17 more	7 hr
Apr 17, 12:10 PM CDT	Mesoscale Discussion	SPC	Anderson, Angelina, Austin, Brazos, Cherokee, Colorado and 19 more	3 hr
Apr 17, 12:38 PM CDT	Mesoscale Discussion	SPC	Atascosa, Bee, DeWitt, Goliad, Gonzales, Karnes and 7 more	37 min
Apr 17, 12:51 PM CDT	Severe Thunderstorm Watch	SPC	Atascosa, Bee, Calhoun, DeWitt, Fayette, Frio and 10 more	5 hr
Apr 17, 1:45 PM CDT	Mesoscale Discussion	SPC	Brazoria, Chambers, Colorado, Fort Bend, Galveston, Hardin and 11 more	2 hr
Apr 17, 3:19 PM CDT	Mesoscale Discussion	SPC	Aransas, Atascosa, Bastrop, Bee, Bell, Bexar and 31 more	56 min
Apr 17, 3:24 PM CDT	Mesoscale Discussion	SPC	Childress, Collingsworth, Cottle, Foard, Gray, Hansford and 13 more	96 min
Apr 17, 3:44 PM CDT	Tornado Watch	SPC	Aransas, Austin, Bee, Brazoria, Calhoun, Chambers and 22 more	6 hr
Apr 17, 5:00 PM CDT	Severe Thunderstorm Watch	SPC	Baylor, Childress, Collingsworth, Cottle, Foard, Hardeman and 13 more	5 hr
Apr 17, 6:50 PM CDT	Mesoscale Discussion	SPC	Aransas, Bee, Brazoria, Calhoun, Chambers, Colorado and 18 more	85 min

Nearby

Mesoscale Discussions in Texas, 2009 Every mesoscale discussion in 2009

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.