Alert archive / Arkansas / Mesoscale Discussions in 2012

Mesoscale Discussion 47

January 22, 201216 counties in Arkansas

The Storm Prediction Center issued this mesoscale discussion at Jan 22, 2012, 6:07 PM CST for 16 counties in Arkansas. It was in force for 53 min.

The area

The outline as issued.

The facts

Issued
Jan 22, 2012, 6:07 PM CST (00:07 UTC)
Expired
Jan 22, 2012, 7:00 PM CST
In force
53 min
Issued by
the Storm Prediction Center

Counties Bradley County, AR, Calhoun County, AR, Clark County, AR, Cleveland County, AR, Columbia County, AR, Dallas County, AR, Grant County, AR, Hempstead County, AR, Hot Spring County, AR, Lafayette County, AR, Miller County, AR, Nevada County, AR, Ouachita County, AR, Pulaski County, AR, Saline County, AR, Union County, AR

The radar

The Little Rock radar (KLZK), 121 km from the middle of the area, began a volume at 00:10 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

Shreveport, LA (KSHV), launched 00:00Z, 0.1 hours before the alert went out and 175 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, Shreveport, LA at 00:00Z on 2012-01-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1190 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, Shreveport, LA at 00:00Z on 2012-01-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 235 square meters per square second.1939587897117Sfc1 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
1190 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
1056 m above ground
0-6 km bulk shear
53 kt
0-1 km storm-relative helicity
235 m²/s²
0-3 km storm-relative helicity
339 m²/s²
Significant tornado parameter
1.8
Supercell composite
6.9

Open this sounding in Storm Lab

The text

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

652 
ACUS11 KWNS 230008
SWOMCD
SPC MCD 230007
ARZ000-LAZ000-TXZ000-230100-

MESOSCALE DISCUSSION 0047
NWS STORM PREDICTION CENTER NORMAN OK
0607 PM CST SUN JAN 22 2012

AREAS AFFECTED...SWRN AR

CONCERNING...TORNADO WATCH 5...

VALID 230007Z - 230100Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 5 CONTINUES.

A NARROW SPATIOTEMPORAL WINDOW EXISTS FOR POTENTIAL SEVERE
DEVELOPMENT IMMEDIATELY SW OF WW 5. TSTMS ARE EXPECTED TO MATURE
INTO WW 5...SUCH THAT AN ADDITIONAL WW IS NOT ANTICIPATED.

LEAD BAND OF TSTMS FROM INDEPENDENCE TO LAFAYETTE COUNTIES CONTINUES
TO GRADUALLY INCREASE IN BOTH REFLECTIVITY AND CG LIGHTNING TRENDS
AS CELLS MATURE WITHIN AN EXTREME LOW-LEVEL SHEAR ENVIRONMENT.
SECONDARY AREA OF CELLS HAVE INCREASED FARTHER W IN CO-LOCATION WITH
THE BAND OF GREATEST DCVA ASSOCIATED WITH THE PIVOTING SHORT WAVE
IMPULSE. AS THIS IMPULSE EJECTS E/NEWD...BOTH AREAS OF TSTMS SHOULD
MORE RAPIDLY MATURE INTO WW 5 THIS EVENING...WITH THIS SCENARIO
APPEARING WELL REPRESENTED BY THE 21Z HRRR. HOWEVER THROUGH ABOUT
02Z...A SMALL CORRIDOR EXISTS FOR ISOLATED SEVERE POTENTIAL
/INCLUDING A TORNADO/ OVER SWRN AR.

..GRAMS.. 01/23/2012

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

ATTN...WFO...LZK...SHV...

LAT...LON   34919200 34399194 33049219 32979283 32979370 33299399
            33629404 33839394 34389337 34809275 34919200

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jan 22, 6:48 PM CSTMesoscale DiscussionSPCArkansas, Bradley, Calhoun, Cleveland, Craighead, Cross and 19 more57 min
Jan 22, 7:59 PM CSTMesoscale DiscussionSPCBradley, Calhoun, Columbia, Ouachita, Union91 min
Jan 22, 8:37 PM CSTMesoscale DiscussionSPCArkansas, Bradley, Chicot, Clay, Craighead, Crittenden and 14 more83 min
Jan 22, 9:47 PM CSTMesoscale DiscussionSPCAshley, Chicot, Crittenden, Desha, Phillips58 min
Jan 22, 10:59 PM CSTTornado WatchSPCAshley, Chicot7 hr

Nearby

Mesoscale Discussions in Arkansas, 2012Every mesoscale discussion in 2012

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.