Alert archive / Arkansas / Mesoscale Discussions in 2014

Mesoscale Discussion 1817

October 6, 201433 counties in Arkansas; DeSoto County, Tate County, Tunica County, Mississippi; 7 counties in Tennessee

The Storm Prediction Center issued this mesoscale discussion at Oct 6, 2014, 5:20 PM CDT for 33 counties in Arkansas; DeSoto County, Tate County, Tunica County, Mississippi; 7 counties in Tennessee. It was in force for 115 min.

The area

The outline as issued.

The facts

Issued
Oct 6, 2014, 5:20 PM CDT (22:20 UTC)
Expired
Oct 6, 2014, 7:15 PM CDT
In force
115 min
Issued by
the Storm Prediction Center
Chance of a watch
40%
All 43 counties

Arkansas County, AR, Clark County, AR, Cleburne County, AR, Cleveland County, AR, Conway County, AR, Crittenden County, AR, Cross County, AR, Dallas County, AR, Faulkner County, AR, Garland County, AR, Grant County, AR, Hot Spring County, AR, Jackson County, AR, Jefferson County, AR, Lee County, AR, Lincoln County, AR, Logan County, AR, Lonoke County, AR, Mississippi County, AR, Monroe County, AR, Montgomery County, AR, Perry County, AR, Phillips County, AR, Poinsett County, AR, Pope County, AR, Prairie County, AR, Pulaski County, AR, Saline County, AR, St. Francis County, AR, Van Buren County, AR, White County, AR, Woodruff County, AR, Yell County, AR, DeSoto County, MS, Tate County, MS, Tunica County, MS, Crockett County, TN, Fayette County, TN, Hardeman County, TN, Haywood County, TN, Lauderdale County, TN, Shelby County, TN, Tipton County, TN

The radar

The Little Rock radar (KLZK), 55 km from the middle of the area, began a volume at 22:22 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

Little Rock, AR (KBYH), launched 12:00Z, 10.3 hours before the alert went out and 163 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-pSkew-T log-p diagram, Little Rock, AR at 12:00Z on 2014-10-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Little Rock, AR at 12:00Z on 2014-10-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 210 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1442 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
210 m²/s²
0-3 km storm-relative helicity
260 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

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.

IssuedProductOfficeCountiesLasted
Oct 5, 10:15 PM CDTMesoscale DiscussionSPCConway, Crawford, Franklin, Garland, Johnson, Logan and 9 more2 hr
Oct 6, 9:31 AM CDTMesoscale DiscussionSPCAdams, Amite, Franklin, Jefferson, Pike, Wilkinson119 min
Oct 6, 3:28 PM CDTMesoscale DiscussionSPCChickasaw, Clay, Itawamba, Lee, Lowndes, Monroe and 3 more62 min
Oct 6, 6:36 PM CDTMesoscale DiscussionSPCAlcorn, Itawamba, Lee, Prentiss, Tishomingo84 min
Oct 6, 2:49 PM CDTMesoscale DiscussionSPCBenton, Carroll, Cheatham, Chester, Clay, Crockett and 35 more56 min

Nearby

Mesoscale Discussions in Arkansas, 2014Mesoscale Discussions in Tennessee, 2014Mesoscale Discussions in Mississippi, 2014Every mesoscale discussion in 2014

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.