Alert archive / Texas / Mesoscale Discussions in 2015

Mesoscale Discussion 245

April 8, 20157 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 8, 2015, 9:34 PM CDT for 7 counties in Texas. It was in force for 56 min.

The area

The outline as issued.

The facts

Issued: Apr 8, 2015, 9:34 PM CDT (02:34 UTC)
Expired: Apr 8, 2015, 10:30 PM CDT
In force: 56 min
Issued by: the Storm Prediction Center

Counties Archer County, TX, Baylor County, TX, Haskell County, TX, Throckmorton County, TX, Wichita County, TX, Wilbarger County, TX, Young County, TX

The radar

The Dyess AFB radar (KDYX), 103 km from the middle of the area, began a volume at 02:38 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

Norman, OK (KOUN), launched 00:00Z, 2.6 hours before the alert went out and 265 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: 427 J/kg
Mixed-layer CIN: -258 J/kg
Mixed-layer LCL: 1139 m above ground
0-6 km bulk shear: 51 kt
0-1 km storm-relative helicity: 251 m²/s²
0-3 km storm-relative helicity: 302 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.3

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 8, 7:23 PM CDT	Severe Thunderstorm Watch	SPC	Borden, Childress, Coke, Cottle, Crosby, Dawson and 27 more	3 hr
Apr 9, 2:15 PM CDT	Mesoscale Discussion	SPC	Bowie, Camp, Cass, Franklin, Gregg, Harrison and 5 more	2 hr
Apr 9, 3:06 PM CDT	Tornado Watch	SPC	Bowie, Camp, Cass, Cherokee, Franklin, Gregg and 11 more	7 hr
Apr 9, 3:17 PM CDT	Severe Thunderstorm Watch	SPC	Anderson, Bell, Delta, Ellis, Falls, Fannin and 16 more	7 hr
Apr 9, 4:53 PM CDT	Mesoscale Discussion	SPC	Bosque, Collin, Comanche, Dallas, Denton, Erath and 8 more	2 hr

Nearby

Mesoscale Discussions in Texas, 2015 Every mesoscale discussion in 2015

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.