Alert archive / Arkansas / Mesoscale Discussions in 2017

Mesoscale Discussion 609

April 30, 20175 states

The Storm Prediction Center issued this mesoscale discussion at Apr 30, 2017, 5:41 AM CDT for 5 states. It was in force for 64 min.

The area

The outline as issued.

The facts

Issued
Apr 30, 2017, 5:41 AM CDT (10:41 UTC)
Expired
Apr 30, 2017, 6:45 AM CDT
In force
64 min
Issued by
the Storm Prediction Center
All 47 counties

Arkansas County, AR, Bradley County, AR, Clay County, AR, Cleveland County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Desha County, AR, Drew 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, St. Francis County, AR, White County, AR, Woodruff County, AR, Union Parish, LA, Dunklin County, MO, Pemiscot County, MO, DeSoto County, MS, Tunica County, MS, Benton County, TN, Carroll County, TN, Chester County, TN, Crockett County, TN, Decatur County, TN, Dyer County, TN, Gibson County, TN, Haywood County, TN, Henderson County, TN, Henry County, TN, Lake County, TN, Lauderdale County, TN, Madison County, TN, Obion County, TN, Shelby County, TN, Tipton County, TN, Weakley County, TN

The radar

The Memphis radar (KNQA), 108 km from the middle of the area, began a volume at 10:40 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 00:00Z, 10.7 hours before the alert went out and 70 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, 12:54 AM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clay and 26 more96 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, 6:12 AM CDTMesoscale DiscussionSPCAshley, Chicot93 min
Apr 30, 1:14 AM CDTMesoscale DiscussionSPCAcadia, Allen, Avoyelles, Beauregard, Calcasieu, Caldwell and 20 more91 min
Apr 30, 6:59 AM CDTMesoscale DiscussionSPCAscension, Assumption, East Baton Rouge, East Feliciana, Jefferson, Lafourche and 12 more2 hr
Apr 30, 7:32 AM CDTTornado WatchSPCAscension, Assumption, East Baton Rouge, East Feliciana, Iberville, Jefferson and 14 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, 1:21 PM CDTMesoscale DiscussionSPCBedford, Cannon, Cheatham, Coffee, Davidson, DeKalb and 21 more54 min
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.