Alert archive / Texas / Mesoscale Discussions in 2016

Mesoscale Discussion 408

April 17, 2016Starr County, Zapata County, Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 17, 2016, 8:21 PM CDT for Starr County, Zapata County, Texas. It was in force for 84 min.

The area

The outline as issued.

The facts

Issued: Apr 17, 2016, 8:21 PM CDT (01:21 UTC)
Expired: Apr 17, 2016, 9:45 PM CDT
In force: 84 min
Issued by: the Storm Prediction Center
Chance of a watch: 20%

Counties Starr County, TX, Zapata County, TX

The radar

The Brownsville radar (KBRO), 183 km from the middle of the area, began a volume at 01:24 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

Corpus Christi, TX (KCRP), launched 00:00Z, 1.4 hours before the alert went out and 195 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: 1949 J/kg
Mixed-layer CIN: -53 J/kg
Mixed-layer LCL: 558 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: 49 m²/s²
0-3 km storm-relative helicity: 104 m²/s²
Significant tornado parameter: 0.6
Supercell composite: 3.5

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
Apr 18, 12:02 AM CDT	Mesoscale Discussion	SPC	Harris, Liberty, Montgomery, San Jacinto	118 min
Apr 18, 4:29 AM CDT	Mesoscale Discussion	SPC	Kinney, Medina, Uvalde	61 min
Apr 18, 5:10 AM CDT	Mesoscale Discussion	SPC	Fort Bend, Harris, Liberty	95 min
Apr 18, 12:57 PM CDT	Mesoscale Discussion	SPC	Brooks, Cameron, Dimmit, Duval, Hidalgo, Jim Hogg and 10 more	2 hr
Apr 18, 3:21 PM CDT	Severe Thunderstorm Watch	SPC	Brooks, Cameron, Duval, Hidalgo, Jim Hogg, Jim Wells and 7 more	8 hr
Apr 18, 5:54 PM CDT	Mesoscale Discussion	SPC	Brooks, Cameron, Dimmit, Duval, Hidalgo, Jim Hogg and 10 more	2 hr

Nearby

Mesoscale Discussions in Texas, 2016 Every mesoscale discussion in 2016

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.