Alert archive / Texas / Mesoscale Discussions in 2018

Mesoscale Discussion 241

April 13, 201820 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 13, 2018, 4:49 PM CDT for 20 counties in Texas. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Apr 13, 2018, 4:49 PM CDT (21:49 UTC)
Expired: Apr 13, 2018, 7:15 PM CDT
In force: 2 hr
Issued by: the Storm Prediction Center
Chance of a watch: 40%

Counties Bastrop County, TX, Bell County, TX, Blanco County, TX, Brazos County, TX, Burleson County, TX, Burnet County, TX, Coryell County, TX, Falls County, TX, Grimes County, TX, Lampasas County, TX, Lee County, TX, Leon County, TX, Llano County, TX, Madison County, TX, McLennan County, TX, Milam County, TX, Robertson County, TX, Travis County, TX, Washington County, TX, Williamson County, TX

The radar

The Ft Hood radar (KGRK), 31 km from the middle of the area, began a volume at 21:52 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, 9.8 hours before the alert went out and 237 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: 731 J/kg
Mixed-layer CIN: -418 J/kg
Mixed-layer LCL: 788 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 189 m²/s²
0-3 km storm-relative helicity: 250 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 13, 11:04 AM CDT	Mesoscale Discussion	SPC	Collin, Cooke, Dallas, Delta, Denton, Ellis and 12 more	56 min
Apr 13, 12:39 PM CDT	Mesoscale Discussion	SPC	Bosque, Collin, Cooke, Dallas, Delta, Denton and 17 more	2 hr
Apr 13, 12:41 PM CDT	Mesoscale Discussion	SPC	Bowie, Camp, Cass, Franklin, Gregg, Harrison and 7 more	2 hr
Apr 13, 1:20 PM CDT	Tornado Watch	SPC	Anderson, Bosque, Collin, Cooke, Dallas, Delta and 24 more	9 hr
Apr 13, 1:50 PM CDT	Tornado Watch PDS	SPC	Angelina, Bowie, Camp, Cass, Cherokee, Franklin and 15 more	8 hr
Apr 13, 3:43 PM CDT	Mesoscale Discussion	SPC	Collin, Dallas, Delta, Denton, Ellis, Fannin and 14 more	92 min
Apr 13, 5:53 PM CDT	Mesoscale Discussion	SPC	Angelina, Bowie, Camp, Cass, Cherokee, Franklin and 20 more	97 min

Nearby

Mesoscale Discussions in Texas, 2018 Every mesoscale discussion in 2018

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.