Alert archive / Arkansas / Mesoscale Discussions in 2010

Mesoscale Discussion 430

April 30, 201021 counties in Arkansas; Howell County, Oregon County, Shannon County, Missouri

The Storm Prediction Center issued this mesoscale discussion at Apr 30, 2010, 7:26 PM CDT for 21 counties in Arkansas; Howell County, Oregon County, Shannon County, Missouri. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Apr 30, 2010, 7:26 PM CDT (00:26 UTC)
Expired
Apr 30, 2010, 9:30 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
All 24 counties

Baxter County, AR, Cleburne County, AR, Conway County, AR, Faulkner County, AR, Fulton County, AR, Garland County, AR, Hot Spring County, AR, Howard County, AR, Independence County, AR, Izard County, AR, Little River County, AR, Montgomery County, AR, Perry County, AR, Pike County, AR, Pulaski County, AR, Saline County, AR, Sevier County, AR, Sharp County, AR, Stone County, AR, Van Buren County, AR, Yell County, AR, Howell County, MO, Oregon County, MO, Shannon County, MO

The radar

The Little Rock radar (KLZK), 71 km from the middle of the area, began a volume at 00:30 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

Springfield, MO (KSGF), launched 00:00Z, 0.4 hours before the alert went out and 197 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, Springfield, MO at 00:00Z on 2010-05-01Temperature 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, Springfield, MO at 00:00Z on 2010-05-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -209 square meters per square second.1939587897Sfc1 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
1925 m above ground
0-6 km bulk shear
81 kt
0-1 km storm-relative helicity
-209 m²/s²
0-3 km storm-relative helicity
122 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

550 
ACUS11 KWNS 010026
SWOMCD
SPC MCD 010026 
MOZ000-ARZ000-OKZ000-010230-

MESOSCALE DISCUSSION 0430
NWS STORM PREDICTION CENTER NORMAN OK
0726 PM CDT FRI APR 30 2010

AREAS AFFECTED...SW INTO CENTRAL AND N CENTRAL AR...S CENTRAL MO

CONCERNING...TORNADO WATCH 116...

VALID 010026Z - 010230Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 116 CONTINUES.

DANGEROUS TORNADO SITUATION UNFOLDING ACROSS AR/SRN MO THIS
EVENING...AND THE TORNADO THREAT WILL CONTINUE INTO THE OVERNIGHT
HOURS.

MULTIPLE DISCRETE SUPERCELLS CONTINUE TO INTENSIFY IN A BROKEN BAND
FROM N OF TXK TO NW OF LIT INTO S CENTRAL MO.  THESE STORMS ARE
MOVING INTO AN ENVIRONMENT WITH STRONG LOW-LEVEL AND DEEP-LAYER
SHEAR...AS WELL AS RICH LOW-LEVEL MOISTURE AND MODERATE INSTABILITY
/PER THE 00Z LZK SOUNDING/.  GIVEN THE OBSERVED STORM STRUCTURES AND
ENVIRONMENT...A FEW STRONG/LONG-TRACK TORNADOES NOW APPEAR LIKELY. 
THE CONVECTIVE MODE AND STORM ENVIRONMENT ARE NOT EXPECTED TO CHANGE
SUBSTANTIALLY INTO THE EARLY OVERNIGHT HOURS...THUS THE SIGNIFICANT
TORNADO THREAT WILL PERSIST WELL AFTER DARK.

..THOMPSON.. 05/01/2010

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...PAH...MEG...LZK...SGF...SHV...

LAT...LON   34899212 34239292 33689423 33929459 34559397 35549279
            36259256 36989196 37369150 36969094 35709152 34899212

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 30, 9:09 PM CDTTornado Watch PDSSPCArkansas, Bradley, Calhoun, Clark, Clay, Cleburne and 49 more7 hr
Apr 30, 10:43 PM CDTMesoscale DiscussionSPCArkansas, Bradley, Calhoun, Clark, Clay, Cleburne and 49 more62 min
Apr 30, 11:41 PM CDTMesoscale DiscussionSPCArkansas, Bradley, Calhoun, Clark, Clay, Cleburne and 45 more64 min
May 1, 2:25 AM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 40 more95 min
May 1, 3:11 AM CDTTornado WatchSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 24 more8 hr
May 1, 6:17 AM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Cleveland and 9 more88 min
May 1, 7:48 AM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Cleveland and 22 more57 min
May 1, 9:52 AM CDTTornado WatchSPCAshley, Chicot8 hr
May 1, 11:19 AM CDTMesoscale DiscussionSPCCrittenden56 min
May 1, 1:37 PM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 38 more53 min
May 1, 3:11 PM CDTMesoscale DiscussionSPCBenton94 min
May 1, 3:18 PM CDTTornado Watch PDSSPCArkansas, Bradley, Calhoun, Clark, Cleburne, Cleveland and 43 more7 hr
May 1, 5:43 PM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Clark, Cleveland and 31 more62 min
Apr 30, 7:12 PM CDTMesoscale DiscussionSPCCrawford, Dent, Franklin, Gasconade, Iron, Jefferson and 13 more63 min
Apr 30, 8:36 PM CDTMesoscale DiscussionSPCBollinger, Cape Girardeau, Iron, Jefferson, Madison, Mississippi and 12 more54 min
Apr 30, 9:03 PM CDTTornado WatchSPCBollinger, Butler, Cape Girardeau, Carter, Iron, Jefferson and 17 more6 hr

Nearby

Mesoscale Discussions in Arkansas, 2010Mesoscale Discussions in Missouri, 2010Every mesoscale discussion in 2010

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.