Alert archive / Arkansas / Mesoscale Discussions in 2017

Mesoscale Discussion 604

April 30, 20175 states

The Storm Prediction Center issued this mesoscale discussion at Apr 30, 2017, 12:54 AM CDT for 5 states. It was in force for 96 min.

The area

The outline as issued.

The facts

Issued
Apr 30, 2017, 12:54 AM CDT (05:54 UTC)
Expired
Apr 30, 2017, 2:30 AM CDT
In force
96 min
Issued by
the Storm Prediction Center
Chance of a watch
60%
All 65 counties

Arkansas County, AR, Ashley County, AR, Bradley County, AR, Calhoun County, AR, Chicot County, AR, Clay County, AR, Cleveland County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Dallas County, AR, Desha County, AR, Drew County, AR, Grant County, AR, Greene County, AR, Independence County, AR, Jackson County, AR, Jefferson County, AR, Lawrence County, AR, Lee County, AR, Lincoln County, AR, Lonoke County, AR, Mississippi County, AR, Monroe County, AR, Phillips County, AR, Poinsett County, AR, Prairie County, AR, Randolph County, AR, Sharp County, AR, St. Francis County, AR, White County, AR, Woodruff County, AR, Ballard County, KY, Carlisle County, KY, Fulton County, KY, Graves County, KY, Hickman County, KY, Butler County, MO, Dunklin County, MO, Mississippi County, MO, New Madrid County, MO, Pemiscot County, MO, Ripley County, MO, Scott County, MO, Stoddard County, MO, Bolivar County, MS, Coahoma County, MS, DeSoto County, MS, Panola County, MS, Quitman County, MS, Sunflower County, MS, Tate County, MS, Tunica County, MS, Washington County, MS, Crockett County, TN, Dyer County, TN, Fayette County, TN, Gibson County, TN, Haywood County, TN, Lake County, TN, Lauderdale County, TN, Obion County, TN, Shelby County, TN, Tipton County, TN, Weakley County, TN

The radar

The Memphis radar (KNQA), 81 km from the middle of the area, began a volume at 05:57 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.

The nearest sounding before it

Little Rock, AR (KBYH), launched 00:00Z, 5.9 hours before the alert went out and 74 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 00:00Z on 2017-04-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1699 joules per kilogram.LCLLFCEL10008507005003002001001 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 00:00Z on 2017-04-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 137 square meters per square second.193958Sfc1 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
1699 J/kg
Mixed-layer CIN
-9 J/kg
Mixed-layer LCL
993 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
137 m²/s²
0-3 km storm-relative helicity
210 m²/s²
Significant tornado parameter
1.2
Supercell composite
11.6

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.

IssuedProductOfficeCountiesLasted
Apr 29, 9:38 PM CDTMesoscale DiscussionSPCClark, Columbia, Hempstead, Hot Spring, Howard, Lafayette and 5 more67 min
Apr 29, 10:23 PM CDTSevere Thunderstorm WatchSPCArkansas, Bradley, Calhoun, Clark, Cleburne, Cleveland and 36 more8 hr
Apr 29, 11:37 PM CDTMesoscale DiscussionSPCBradley, Calhoun, Clark, Cleveland, Columbia, Conway and 23 more53 min
Apr 30, 1:10 AM CDTSevere Thunderstorm WatchSPCClay, Craighead, Crittenden, Cross, Greene, Lee and 4 more6 hr
Apr 30, 1:49 AM CDTTornado WatchSPCAshley, Chicot7 hr
Apr 30, 2:58 AM CDTMesoscale DiscussionSPCCrittenden, Cross, Lee, Mississippi, Phillips, Poinsett and 1 more92 min
Apr 30, 3:36 AM CDTMesoscale DiscussionSPCArkansas, Bradley, Calhoun, Cleveland, Desha, Drew and 10 more84 min
Apr 30, 5:41 AM CDTMesoscale DiscussionSPCArkansas, Bradley, Clay, Cleveland, Craighead, Crittenden and 19 more64 min
Apr 30, 6:12 AM CDTMesoscale DiscussionSPCAshley, Chicot93 min
Apr 30, 1:21 PM CDTMesoscale DiscussionSPCSimpson54 min
Apr 30, 1:58 PM CDTMesoscale DiscussionSPCGreenup2 hr
Apr 30, 3:58 PM CDTMesoscale DiscussionSPCAdair, Barren, Boyle, Casey, Clinton, Cumberland and 14 more92 min
Apr 30, 1:14 AM CDTMesoscale DiscussionSPCAdams, Claiborne, Jefferson, Wilkinson91 min
Apr 30, 6:59 AM CDTMesoscale DiscussionSPCAmite, Attala, Calhoun, Carroll, Chickasaw, Choctaw and 50 more2 hr
Apr 30, 7:32 AM CDTTornado WatchSPCAmite, Attala, Carroll, Choctaw, Clarke, Clay and 42 more7 hr
Apr 30, 10:06 AM CDTMesoscale DiscussionSPCChickasaw, Itawamba, Lee, Monroe, Pontotoc, Prentiss and 2 more84 min
Apr 30, 10:36 AM CDTTornado WatchSPCAlcorn, Benton, Calhoun, Chickasaw, Itawamba, Lafayette and 9 more8 hr
Apr 30, 1:36 PM CDTTornado WatchSPCBedford, Bledsoe, Bradley, Cannon, Cheatham, Clay and 32 more5 hr
Apr 30, 3:42 PM CDTMesoscale DiscussionSPCBledsoe, Bradley, Cannon, Coffee, Cumberland, DeKalb and 15 more2 hr

Nearby

Mesoscale Discussions in Arkansas, 2017Mesoscale Discussions in Tennessee, 2017Mesoscale Discussions in Mississippi, 2017Every mesoscale discussion in 2017

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.