Mesoscale Discussion 321

Issued

Apr 11, 2014, 2:36 PM CDT (19:36 UTC)

Expired

Apr 11, 2014, 4:30 PM CDT

In force

114 min

Issued by

the Storm Prediction Center

Chance of a watch

20%

The Memphis radar (KNQA), 164 km from the middle of the area, began a volume at 19:38 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.

369 
ACUS11 KWNS 111937
SWOMCD
SPC MCD 111936 
TNZ000-KYZ000-MOZ000-ARZ000-112130-

MESOSCALE DISCUSSION 0321
NWS STORM PREDICTION CENTER NORMAN OK
0236 PM CDT FRI APR 11 2014

AREAS AFFECTED...PARTS OF SRN MO...NRN AR AND ADJACENT PORTIONS OF
SWRN KY...NWRN TN

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 111936Z - 112130Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...ISOLATED STRONG/SEVERE STORMS APPEAR POSSIBLE THROUGH LATE
AFTERNOON.  DUE TO THE CONFINED NATURE OF THE SEVERE RISK AREA...
AND THE MARGINAL NATURE OF THE SEVERE THREAT...THE NEED FOR A WATCH
IS NOT CURRENTLY ANTICIPATED.

DISCUSSION...RECENT THUNDERSTORM DEVELOPMENT...NORTH OF THE
MISSOURI/ARKANSAS BORDER BETWEEN WEST PLAINS AND POPLAR
BLUFF...APPEARS MOSTLY IN RESPONSE TO FORCING ASSOCIATED WITH WARM
ADVECTION...BASED NEAR OR JUST BELOW 700 MB.  THE LATEST RAPID
REFRESH SUGGESTS THAT THIS ZONE LIKELY WILL REMAIN FOCUSED IN THE
VICINITY OF THE MISSOURI/ARKANSAS BORDER AREA THROUGH THE REST OF
THE AFTERNOON...ON THE NORTHERN EDGE OF A WARMER AND MORE STRONGLY
CAPPING MID-LEVEL AIR MASS.

DURING THE NEXT FEW HOURS...WITH CONTINUED SURFACE HEATING AND
BOUNDARY LAYER MIXING...STRONGER STORMS PROBABLY WILL EVENTUALLY
BECOME ROOTED IN A MODESTLY MOIST BOUNDARY LAYER CHARACTERIZED BY
CAPE OF 500-1000+ J/KG...BENEATH RELATIVELY STEEP MID-LEVEL LAPSE
RATES.  ALTHOUGH LOWER/MID TROPOSPHERIC FLOW FIELDS ARE WEAK...DEEP
LAYER SHEAR BENEATH WESTERLY 500 MB FLOW /STRENGTHENING TO 40+ KTS/
MAY BE SUFFICIENT TO SUPPORT AT LEAST OCCASIONAL SHORT LIVED
SUPERCELL STRUCTURES...AS ACTIVITY PROPAGATES EAST SOUTHEASTWARD
ACROSS PARTS OF NORTHEAST ARKANSAS ...THE MISSOURI BOOTHEEL AND
ADJACENT PORTIONS OF THE MIDDLE MISSISSIPPI VALLEY THROUGH 22-00Z.

HAIL OCCASIONALLY EXCEEDING 1 INCH IN DIAMETER APPEARS TO BE THE
PRIMARY SEVERE THREAT...BUT LOCALLY STRONG WIND GUSTS MAY NOT BE OUT
OF THE QUESTION.

..KERR/HART.. 04/11/2014

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

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

LAT...LON   36849161 36759037 36518914 35848914 35719055 35919129
            36119264 36469290 36849250 36849161

Mesoscale Discussions in Arkansas, 2014Mesoscale Discussions in Missouri, 2014Mesoscale Discussions in Tennessee, 2014Every mesoscale discussion in 2014

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.