Alert archive / Texas / Mesoscale Discussions in 2018

Mesoscale Discussion 280

April 21, 201817 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 21, 2018, 1:41 PM CDT for 17 counties in Texas. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
Apr 21, 2018, 1:41 PM CDT (18:41 UTC)
Expired
Apr 21, 2018, 4:15 PM CDT
In force
3 hr
Issued by
the Storm Prediction Center
Chance of a watch
20%

Counties Bosque County, TX, Eastland County, TX, Erath County, TX, Haskell County, TX, Hill County, TX, Hood County, TX, Jack County, TX, Johnson County, TX, Palo Pinto County, TX, Parker County, TX, Shackelford County, TX, Somervell County, TX, Stephens County, TX, Tarrant County, TX, Throckmorton County, TX, Wise County, TX, Young County, TX

The radar

The Dyess AFB radar (KDYX), 74 km from the middle of the area, began a volume at 18:41 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, 6.7 hours before the alert went out and 112 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-pSkew-T log-p diagram, Fort Worth, TX at 12:00Z on 2018-04-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Fort Worth, TX at 12:00Z on 2018-04-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 317 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1046 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
317 m²/s²
0-3 km storm-relative helicity
320 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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Nearby

Mesoscale Discussions in Texas, 2018Every 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.