Alert archive / Arkansas / Mesoscale Discussions in 2009

Mesoscale Discussion 2162

October 29, 200919 counties in Arkansas

The Storm Prediction Center issued this mesoscale discussion at Oct 29, 2009, 7:05 PM CDT for 19 counties in Arkansas. It was in force for 55 min.

The area

The outline as issued.

The facts

Issued: Oct 29, 2009, 7:05 PM CDT (00:05 UTC)
Expired: Oct 29, 2009, 8:00 PM CDT
In force: 55 min
Issued by: the Storm Prediction Center

Counties Bradley County, AR, Calhoun County, AR, Clark County, AR, Cleveland County, AR, Dallas County, AR, Garland County, AR, Grant County, AR, Hot Spring County, AR, Jefferson County, AR, Lonoke County, AR, Montgomery County, AR, Ouachita County, AR, Perry County, AR, Pike County, AR, Polk County, AR, Pulaski County, AR, Saline County, AR, Scott County, AR, Yell County, AR

The radar

The Little Rock radar (KLZK), 75 km from the middle of the area, began a volume at 00:08 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

Shreveport, LA (KSHV), launched 00:00Z, 0.1 hours before the alert went out and 224 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: 1620 J/kg
Mixed-layer CIN: -34 J/kg
Mixed-layer LCL: 510 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 278 m²/s²
0-3 km storm-relative helicity: 300 m²/s²
Significant tornado parameter: 2.2
Supercell composite: 14.3

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
Oct 29, 8:24 PM CDT	Mesoscale Discussion	SPC	Baxter, Boone, Carroll, Cleburne, Conway, Faulkner and 20 more	66 min
Oct 29, 9:07 PM CDT	Mesoscale Discussion	SPC	Calhoun, Cleveland, Columbia, Dallas, Grant, Hot Spring and 8 more	53 min
Oct 29, 10:30 PM CDT	Mesoscale Discussion	SPC	Arkansas, Ashley, Bradley, Calhoun, Cleveland, Dallas and 8 more	60 min
Oct 30, 2:03 AM CDT	Mesoscale Discussion	SPC	Chicot, Crittenden, Desha, Lee, Mississippi, Phillips	57 min

Nearby

Mesoscale Discussions in Arkansas, 2009 Every mesoscale discussion in 2009

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.