Alert archive / Missouri / Mesoscale Discussions in 2011

Mesoscale Discussion 2045

August 23, 2011Clay County, Greene County, Randolph County, Arkansas; 8 counties in Missouri; Lake County, Tennessee

The Storm Prediction Center issued this mesoscale discussion at Aug 23, 2011, 5:25 PM CDT for Clay County, Greene County, Randolph County, Arkansas; 8 counties in Missouri; Lake County, Tennessee. It was in force for 65 min.

The area

The outline as issued.

The facts

Issued
Aug 23, 2011, 5:25 PM CDT (22:25 UTC)
Expired
Aug 23, 2011, 6:30 PM CDT
In force
65 min
Issued by
the Storm Prediction Center

Counties Clay County, AR, Greene County, AR, Randolph County, AR, Butler County, MO, Dunklin County, MO, Mississippi County, MO, New Madrid County, MO, Pemiscot County, MO, Scott County, MO, Stoddard County, MO, Wayne County, MO, Lake County, TN

The radar

The Memphis radar (KNQA), 129 km from the middle of the area, began a volume at 22:26 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 (KLZK), launched 12:00Z, 10.4 hours before the alert went out and 184 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 2011-08-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4250 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 12:00Z on 2011-08-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -16 square meters per square second.1939Sfc1 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
4250 J/kg
Mixed-layer CIN
-19 J/kg
Mixed-layer LCL
740 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
-16 m²/s²
0-3 km storm-relative helicity
49 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

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

073 
ACUS11 KWNS 232225
SWOMCD
SPC MCD 232225 
TNZ000-KYZ000-MOZ000-ILZ000-ARZ000-232330-

MESOSCALE DISCUSSION 2045
NWS STORM PREDICTION CENTER NORMAN OK
0525 PM CDT TUE AUG 23 2011

AREAS AFFECTED...NERN ARK / SERN MO

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 232225Z - 232330Z

A FEW ISOLD REPORTS OF LARGE HAIL/WIND DMG MAY OCCUR THRU DUSK OVER
SERN MO AND NERN ARK.  ISOLD COVERAGE/EXPECTED STORM INTENSITY
PRECLUDE THE NEED FOR A WW.

LOW LEVEL SLYS W OF A RESIDUAL FRONT DRAPED FROM IL SWD INTO NERN MS
ARE WITHIN A RESERVOIR OF HIGH PW /AOA 2 INCHES/.  THIS IS
CONTRIBUTING TO A VERY UNSTABLE AIRMASS /3000 J/KG MLCAPE/ PER RUC
FORECAST SOUNDINGS ACROSS THE DISCUSSION AREA.  SUBSTANTIAL VEERING
WIND PROFILES ARE UNDERNEATH A PLUME OF MODERATE NWLY FLOW ALOFT
EXTENDING SWD INTO THE REGION FROM THE MIDWEST...AND IS RESULTING IN
30-40 KTS EFFECTIVE SHEAR AND THIS MAY AID IN SOME STORM
ORGANIZATION.  CURRENT THINKING IS ONGOING ACTIVITY SHOULD PERSIST
INTO THE EARLY EVENING HOURS POSING AN ISOLD LARGE
HAIL/STRONG-SEVERE WIND GUST THREAT.

..SMITH.. 08/23/2011

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

ATTN...WFO...PAH...MEG...

LAT...LON   35859065 36149117 37189055 37269002 37068930 36568924
            35938983 35859065

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 23, 4:40 PM CDTMesoscale DiscussionSPCColumbia, Lafayette, Miller35 min

Nearby

Mesoscale Discussions in Missouri, 2011Mesoscale Discussions in Arkansas, 2011Mesoscale Discussions in Tennessee, 2011Every mesoscale discussion in 2011

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.