Alert archive / Missouri / Mesoscale Discussions in 2021

Mesoscale Discussion 567

May 9, 202110 counties in Arkansas; 20 counties in Missouri

The Storm Prediction Center issued this mesoscale discussion at May 9, 2021, 3:46 AM CDT for 10 counties in Arkansas; 20 counties in Missouri. It was in force for 119 min.

The area

The outline as issued.

The facts

Issued
May 9, 2021, 3:46 AM CDT (08:46 UTC)
Expired
May 9, 2021, 5:45 AM CDT
In force
119 min
Issued by
the Storm Prediction Center
Concerning
Severe potential...watch unlikely
Chance of a watch
20%
All 30 counties

Baxter County, AR, Boone County, AR, Carroll County, AR, Fulton County, AR, Izard County, AR, Madison County, AR, Marion County, AR, Newton County, AR, Searcy County, AR, Sharp County, AR, Camden County, MO, Christian County, MO, Dade County, MO, Dallas County, MO, Dent County, MO, Douglas County, MO, Greene County, MO, Hickory County, MO, Howell County, MO, Laclede County, MO, Oregon County, MO, Ozark County, MO, Polk County, MO, Pulaski County, MO, Shannon County, MO, Stone County, MO, Taney County, MO, Texas County, MO, Webster County, MO, Wright County, MO

The radar

The Springfield radar (KSGF), 70 km from the middle of the area, began a volume at 08:45 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

Springfield, MO (KSGF), launched 00:00Z, 8.8 hours before the alert went out and 88 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 2021-05-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Springfield, MO at 00:00Z on 2021-05-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 177 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
2 J/kg
Mixed-layer CIN
-429 J/kg
Mixed-layer LCL
2095 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
177 m²/s²
0-3 km storm-relative helicity
370 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

355 
ACUS11 KWNS 090846
SWOMCD
SPC MCD 090846 
MOZ000-ARZ000-091045-

Mesoscale Discussion 0567
NWS Storm Prediction Center Norman OK
0346 AM CDT Sun May 09 2021

Areas affected...southern Missouri/northern Arkansas

Concerning...Severe potential...Watch unlikely 

Valid 090846Z - 091045Z

Probability of Watch Issuance...20 percent

SUMMARY...Locally strong storms -- a few capable of hail and/or wind
gusts near severe levels -- will be possible across the Ozarks
region this morning.  However, low-end/isolated risk that is
expected to persist appears likely to remain too low to warrant new
WW issuance.

DISCUSSION...Latest radar loop shows a mature, arcing band of
thunderstorms moving southeastward across southwestern and central
Missouri at this time.  Meanwhile, isolated storms have developed
farther south, across northwestern Arkansas/southwestern Missouri,
in response to increasing low-level warm advection associated with a
veering low-level jet.

Amply steep lapse rates across the region are providing sufficient
-- though slightly elevated -- CAPE, on the order of 500 to 1500
J/kg.  This -- combined with moderate/very weakly veering flow in
the cloud-bearing layer -- is supporting a few stronger updrafts,
and will likely continue to do so as convection spreads across the
Ozarks.  However, with severe potential expected to remain rather
low-end and isolated, a WW is not currently anticipated.  We will
continue to monitor convective evolution across the area, for any
signs of increased severe risk.

..Goss/Guyer.. 05/09/2021

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...PAH...LSX...LZK...SGF...TSA...

LAT...LON   35599418 36579347 37109373 37499419 38279308 38109231
            37389112 36869121 36179109 35889236 35599418

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 9, 12:14 PM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 46 more91 min
May 9, 1:14 PM CDTSevere Thunderstorm WatchSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 33 more8 hr
May 9, 2:27 PM CDTSevere Thunderstorm WatchSPCCraighead, Crittenden, Cross, Lee, Mississippi, Phillips and 2 more7 hr
May 9, 3:42 PM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Clark, Cleveland and 31 more93 min
May 9, 5:41 PM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 16 more2 hr
May 9, 5:48 PM CDTMesoscale DiscussionSPCCrittenden, Lee, Phillips, St. Francis87 min
May 8, 9:15 PM CDTMesoscale DiscussionSPCBarton, Bates, Benton, Buchanan, Caldwell, Camden and 29 more2 hr
May 8, 9:51 PM CDTSevere Thunderstorm WatchSPCBates, Benton, Boone, Buchanan, Caldwell, Camden and 22 more7 hr
May 8, 11:25 PM CDTMesoscale DiscussionSPCCass, Clay, Henry, Jackson, Johnson, Lafayette2 hr
May 9, 1:39 AM CDTMesoscale DiscussionSPCBates, Benton, Boone, Camden, Cass, Cedar and 21 more96 min

Nearby

Mesoscale Discussions in Missouri, 2021Mesoscale Discussions in Arkansas, 2021Every mesoscale discussion in 2021

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.