Alert archive / Arkansas / Mesoscale Discussions in 2022

Mesoscale Discussion 451

April 11, 202216 counties in Arkansas

The Storm Prediction Center issued this mesoscale discussion at Apr 11, 2022, 7:50 PM CDT for 16 counties in Arkansas. It was in force for 115 min.

The area

The outline as issued.

The facts

Issued: Apr 11, 2022, 7:50 PM CDT (00:50 UTC)
Expired: Apr 11, 2022, 9:45 PM CDT
In force: 115 min
Issued by: the Storm Prediction Center
Concerning: Tornado watch 107

Counties Conway County, AR, Faulkner County, AR, Johnson County, AR, Lee County, AR, Logan County, AR, Lonoke County, AR, Monroe County, AR, Perry County, AR, Pope County, AR, Prairie County, AR, Pulaski County, AR, Saline County, AR, St. Francis County, AR, White County, AR, Woodruff County, AR, Yell County, AR

The radar

The Little Rock radar (KLZK), 52 km from the middle of the area, began a volume at 00:52 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Severe Thunderstorm Watch 109Apr 11, 9:20 PM CDT

The nearest sounding before it

Little Rock, AR (KLZK), launched 00:00Z, 0.8 hours before the alert went out and 242 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: 1560 J/kg
Mixed-layer CIN: -13 J/kg
Mixed-layer LCL: 930 m above ground
0-6 km bulk shear: 55 kt
0-1 km storm-relative helicity: 163 m²/s²
0-3 km storm-relative helicity: 269 m²/s²
Significant tornado parameter: 2.0
Supercell composite: 13.6

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 11, 9:18 PM CDT	Severe Thunderstorm Watch	SPC	Crittenden, Cross, Lee, Phillips, St. Francis	6 hr
Apr 11, 11:55 PM CDT	Mesoscale Discussion	SPC	Cross, St. Francis, White, Woodruff	2 hr
Apr 12, 6:59 PM CDT	Mesoscale Discussion	SPC	Bradley, Calhoun, Clark, Columbia, Dallas, Hempstead and 7 more	2 hr

Nearby

Mesoscale Discussions in Arkansas, 2022 Every mesoscale discussion in 2022

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.