Alert archive / Arkansas / Mesoscale Discussions in 2015

Mesoscale Discussion 1618

August 5, 201534 counties in Arkansas; Dunklin County, Missouri

The Storm Prediction Center issued this mesoscale discussion at Aug 5, 2015, 1:06 PM CDT for 34 counties in Arkansas; Dunklin County, Missouri. It was in force for 114 min.

The area

The outline as issued.

The facts

Issued: Aug 5, 2015, 1:06 PM CDT (18:06 UTC)
Expired: Aug 5, 2015, 3:00 PM CDT
In force: 114 min
Issued by: the Storm Prediction Center
Chance of a watch: 40%

All 35 counties

Arkansas County, AR, Cleburne County, AR, Conway County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Faulkner County, AR, Garland County, AR, Grant County, AR, Greene County, AR, Hot Spring County, AR, Independence County, AR, Izard County, AR, Jackson County, AR, Jefferson County, AR, Lawrence County, AR, Lee County, AR, Lonoke County, AR, Mississippi County, AR, Monroe County, AR, Montgomery County, AR, Perry County, AR, Poinsett County, AR, Pope County, AR, Prairie County, AR, Pulaski County, AR, Saline County, AR, Sharp County, AR, St. Francis County, AR, Stone County, AR, Van Buren County, AR, White County, AR, Woodruff County, AR, Yell County, AR, Dunklin County, MO

The radar

The Little Rock radar (KLZK), 39 km from the middle of the area, began a volume at 18:06 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 473Aug 5, 2:00 PM CDT

The nearest sounding before it

Little Rock, AR (KLZK), launched 12:00Z, 6.1 hours before the alert went out and 207 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: 548 J/kg
Mixed-layer CIN: -93 J/kg
Mixed-layer LCL: 1601 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 61 m²/s²
0-3 km storm-relative helicity: 100 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

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
Aug 5, 8:08 AM CDT	Mesoscale Discussion	SPC	Benton, Boone, Carroll, Crawford, Franklin, Johnson and 3 more	97 min
Aug 5, 1:59 PM CDT	Severe Thunderstorm Watch	SPC	Arkansas, Clay, Cleburne, Craighead, Crittenden, Cross and 21 more	4 hr
Aug 5, 3:53 PM CDT	Mesoscale Discussion	SPC	Craighead, Crittenden, Cross, Greene, Lee, Lonoke and 7 more	97 min
Aug 5, 4:21 AM CDT	Severe Thunderstorm Watch	SPC	Barton, Jasper, McDonald, Newton, Vernon	6 hr
Aug 5, 6:40 AM CDT	Mesoscale Discussion	SPC	Barton, Jasper, McDonald, Newton, Vernon	95 min

Nearby

Mesoscale Discussions in Arkansas, 2015 Mesoscale Discussions in Missouri, 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.