Alert archive / Texas / Mesoscale Discussions in 2019

Mesoscale Discussion 2091

October 20, 20194 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Oct 20, 2019, 9:08 PM CDT for 4 counties in Texas. It was in force for 37 min.

The area

The outline as issued.

The facts

Issued: Oct 20, 2019, 9:08 PM CDT (02:08 UTC)
Expired: Oct 20, 2019, 9:45 PM CDT
In force: 37 min
Issued by: the Storm Prediction Center

Counties Collin County, TX, Dallas County, TX, Hunt County, TX, Rockwall County, TX

The radar

The Dallas/Ft Worth radar (KFWS), 87 km from the middle of the area, began a volume at 02:07 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 00:00Z, 2.1 hours before the alert went out and 75 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: 1660 J/kg
Mixed-layer CIN: -93 J/kg
Mixed-layer LCL: 1347 m above ground
0-6 km bulk shear: 58 kt
0-1 km storm-relative helicity: 216 m²/s²
0-3 km storm-relative helicity: 243 m²/s²
Significant tornado parameter: 1.2
Supercell composite: 14.5

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
Oct 20, 7:01 PM CDT	Tornado Watch	SPC	Bosque, Bowie, Camp, Cass, Collin, Comanche and 43 more	7 hr
Oct 20, 8:36 PM CDT	Mesoscale Discussion	SPC	Collin, Dallas, Hunt, Johnson, Kaufman, Rockwall and 1 more	54 min
Oct 20, 9:55 PM CDT	Mesoscale Discussion	SPC	Brown, Callahan, Coleman, Concho, Kimble, Lampasas and 10 more	2 hr
Oct 20, 11:46 PM CDT	Mesoscale Discussion	SPC	Bosque, Collin, Comanche, Dallas, Denton, Ellis and 12 more	89 min
Oct 21, 12:40 AM CDT	Mesoscale Discussion	SPC	Cameron, Willacy	35 min
Oct 21, 1:50 AM CDT	Tornado Watch	SPC	Anderson, Bell, Bosque, Bowie, Brazos, Camp and 35 more	5 hr

Nearby

Mesoscale Discussions in Texas, 2019 Every mesoscale discussion in 2019

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.