Alert archive / Texas / Mesoscale Discussions in 2018

Mesoscale Discussion 225

April 6, 201824 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 6, 2018, 6:45 PM CDT for 24 counties in Texas. It was in force for 90 min.

The area

The outline as issued.

The facts

Issued: Apr 6, 2018, 6:45 PM CDT (23:45 UTC)
Expired: Apr 6, 2018, 8:15 PM CDT
In force: 90 min
Issued by: the Storm Prediction Center

All 24 counties

Bell County, TX, Bosque County, TX, Collin County, TX, Coryell County, TX, Dallas County, TX, Delta County, TX, Ellis County, TX, Falls County, TX, Fannin County, TX, Freestone County, TX, Henderson County, TX, Hill County, TX, Hopkins County, TX, Hunt County, TX, Johnson County, TX, Kaufman County, TX, Lampasas County, TX, Limestone County, TX, McLennan County, TX, Milam County, TX, Navarro County, TX, Rains County, TX, Rockwall County, TX, Van Zandt County, TX

The radar

The Dallas/Ft Worth radar (KFWS), 48 km from the middle of the area, began a volume at 23:46 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, 11.8 hours before the alert went out and 72 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: 787 J/kg
Mixed-layer CIN: -166 J/kg
Mixed-layer LCL: 650 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: 244 m²/s²
0-3 km storm-relative helicity: 281 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 3.0

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 6, 3:20 PM CDT	Tornado Watch	SPC	Angelina, Bowie, Camp, Cass, Cherokee, Franklin and 15 more	8 hr
Apr 6, 3:40 PM CDT	Mesoscale Discussion	SPC	Anderson, Collin, Dallas, Ellis, Freestone, Henderson and 8 more	3 hr
Apr 6, 4:00 PM CDT	Severe Thunderstorm Watch	SPC	Anderson, Bell, Bosque, Collin, Cooke, Coryell and 32 more	8 hr
Apr 6, 6:02 PM CDT	Mesoscale Discussion	SPC	Bowie, Camp, Cass, Cherokee, Franklin, Gregg and 12 more	58 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.