Alert archive / Oklahoma / Mesoscale Discussions in 2012

Mesoscale Discussion 478

April 9, 201210 counties in Kansas; 13 counties in Oklahoma; Hemphill County, Lipscomb County, Wheeler County, Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 9, 2012, 1:54 PM CDT for 10 counties in Kansas; 13 counties in Oklahoma; Hemphill County, Lipscomb County, Wheeler County, Texas. It was in force for 96 min.

The area

The outline as issued.

The facts

Issued: Apr 9, 2012, 1:54 PM CDT (18:54 UTC)
Expired: Apr 9, 2012, 3:30 PM CDT
In force: 96 min
Issued by: the Storm Prediction Center

All 26 counties

Barber County, KS, Clark County, KS, Comanche County, KS, Edwards County, KS, Ford County, KS, Gray County, KS, Hodgeman County, KS, Kiowa County, KS, Meade County, KS, Pratt County, KS, Alfalfa County, OK, Beaver County, OK, Blaine County, OK, Custer County, OK, Dewey County, OK, Ellis County, OK, Garfield County, OK, Grant County, OK, Harper County, OK, Major County, OK, Roger Mills County, OK, Woods County, OK, Woodward County, OK, Hemphill County, TX, Lipscomb County, TX, Wheeler County, TX

The radar

The Dodge City radar (KDDC), 113 km from the middle of the area, began a volume at 18:58 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

Dodge City, (KDDC), launched 12:00Z, 6.9 hours before the alert went out and 113 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1086 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 15 m²/s²
0-3 km storm-relative helicity: 64 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

806 
ACUS11 KWNS 091854
SWOMCD
SPC MCD 091854 
OKZ000-KSZ000-TXZ000-092030-

MESOSCALE DISCUSSION 0478
NWS STORM PREDICTION CENTER NORMAN OK
0154 PM CDT MON APR 09 2012

AREAS AFFECTED...ERN PORTIONS OF THE TX/OK PANHANDLES/SWRN KS/WRN OK

CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY 

VALID 091854Z - 092030Z

SLOWLY INCREASING SEVERE/TORNADO POTENTIAL ACROSS THE DISCUSSION
AREA WILL LIKELY WARRANT TORNADO WATCH ISSUANCE IN THE NEXT HOUR OR
SO.

VISIBLE IMAGERY SHOWS CLEARING ACROSS THE ERN TX/OK PANHANDLES AND
INTO WRN OK...WHILE A MID CLOUD DECK CONTINUES EXPANDING FARTHER TO
THE W ACROSS THE TX PANHANDLE.  AS A RESULT...APPRECIABLE HEATING
CONTINUES...WITH OBJECTIVE ANALYSES NOW INDICATING ROUGHLY 1500 J/KG
MIXED-LAYER CAPE OVER THE ERN PANHANDLES AND ADJACENT WRN OK/SWRN KS
E OF THE MOISTURE GRADIENT/WEAK DRYLINE.  

THE AFOREMENTIONED MID CLOUD DECK LIKELY REPRESENTATIVE OF THE
LEADING EDGE OF ENHANCED LARGE-SCALE ASCENT ASSOCIATED WITH VERY
SUBTLE SHORT-WAVE TROUGHING ALOFT NOW SPREADING INTO THIS AREA. 
THUS...EXPECT THAT STORM DEVELOPMENT IS BECOMING INCREASINGLY
IMMINENT -- POSSIBLY ARISING FROM WITHIN A NEW CU FIELD NOW
DEVELOPING OVER BEAVER CO OK/CLARK CO KS NEAR THE WELL-DEFINED
SURFACE WARM FRONT.

GREATEST LOW-LEVEL SHEAR -- AND THUS MOST SUBSTANTIAL TORNADO
POTENTIAL -- IS APPARENT NEAR AND TO THE COOL SIDE OF THE WARM
FRONT...BUT WITH LOW CLOUDS -- AND THUS A STABLE BOUNDARY LAYER --
STILL PERSISTENT ACROSS MOST OF WRN KS...THE CORRIDOR OF POTENTIAL
IS FAIRLY NARROW ATTM.  S OF THE FRONT...THREATS FOR LARGE HAIL AND
DAMAGING WINDS SHOULD PREDOMINATE...WITH ACTIVITY SPREADING ESEWD
INTO WRN OK THROUGH LATE AFTERNOON.

..GOSS.. 04/09/2012

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

ATTN...WFO...ICT...OUN...DDC...AMA...

LAT...LON   38350079 38039945 37499831 36479753 35849845 35319906
            35299923 35260066 36640060 37610066 38350079

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 9, 2:28 PM CDT	Tornado Watch	SPC	Barber, Clark, Comanche	5 hr
Apr 9, 3:06 PM CDT	Mesoscale Discussion	SPC	Beckham, Greer, Harmon, Jackson, Kiowa, Roger Mills and 1 more	54 min
Apr 9, 3:23 PM CDT	Severe Thunderstorm Watch	SPC	Beckham, Caddo, Comanche, Custer, Greer, Harmon and 5 more	8 hr
Apr 9, 5:37 PM CDT	Mesoscale Discussion	SPC	Beckham, Custer, Greer, Harmon, Jackson, Kiowa and 2 more	83 min
Apr 9, 6:27 PM CDT	Tornado Watch	SPC	Beckham, Blaine, Caddo, Comanche, Cotton, Custer and 11 more	8 hr
Apr 9, 5:03 PM CDT	Mesoscale Discussion	SPC	Andrews, Crane, Dawson, Ector, Gaines, Jeff Davis and 9 more	87 min
Apr 9, 5:32 PM CDT	Severe Thunderstorm Watch	SPC	Andrews, Brewster, Crane, Crockett, Culberson, Dawson and 18 more	7 hr

Nearby

Mesoscale Discussions in Oklahoma, 2012 Mesoscale Discussions in Kansas, 2012 Mesoscale Discussions in Texas, 2012 Every 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.