Alert archive / Oklahoma / Mesoscale Discussions in 2011

Mesoscale Discussion 816

May 19, 201124 counties in Oklahoma; 6 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 19, 2011, 5:21 PM CDT for 24 counties in Oklahoma; 6 counties in Texas. It was in force for 84 min.

The area

The outline as issued.

The facts

Issued: May 19, 2011, 5:21 PM CDT (22:21 UTC)
Expired: May 19, 2011, 6:45 PM CDT
In force: 84 min
Issued by: the Storm Prediction Center

All 30 counties

Alfalfa County, OK, Blaine County, OK, Caddo County, OK, Canadian County, OK, Cleveland County, OK, Comanche County, OK, Cotton County, OK, Custer County, OK, Dewey County, OK, Garfield County, OK, Grady County, OK, Grant County, OK, Jackson County, OK, Kingfisher County, OK, Kiowa County, OK, Logan County, OK, Major County, OK, McClain County, OK, Noble County, OK, Oklahoma County, OK, Stephens County, OK, Tillman County, OK, Washita County, OK, Woods County, OK, Archer County, TX, Baylor County, TX, Haskell County, TX, Knox County, TX, Wichita County, TX, Wilbarger County, TX

The radar

The Altus AFB radar (KFDR), 73 km from the middle of the area, began a volume at 22:24 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

Norman, OK (KOUN), launched 12:00Z, 10.4 hours before the alert went out and 103 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: 1483 J/kg
Mixed-layer CIN: -94 J/kg
Mixed-layer LCL: 616 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 219 m²/s²
0-3 km storm-relative helicity: 186 m²/s²
Significant tornado parameter: 0.6
Supercell composite: 2.1

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
May 19, 12:30 PM CDT	Mesoscale Discussion	SPC	Beckham, Blaine, Caddo, Comanche, Custer, Dewey and 12 more	30 min
May 19, 12:46 PM CDT	Tornado Watch	SPC	Alfalfa, Beckham, Blaine, Caddo, Canadian, Cleveland and 28 more	9 hr
May 19, 3:44 PM CDT	Mesoscale Discussion	SPC	Alfalfa, Beckham, Blaine, Caddo, Canadian, Comanche and 16 more	61 min

Nearby

Mesoscale Discussions in Oklahoma, 2011 Mesoscale Discussions in Texas, 2011 Every mesoscale discussion in 2011

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.