Alert archive / Oklahoma / Mesoscale Discussions in 2003

Mesoscale Discussion 787

May 6, 20035 counties in Arkansas; McDonald County, Missouri; 25 counties in Oklahoma

The Storm Prediction Center issued this mesoscale discussion at May 6, 2003, 10:32 AM CDT for 5 counties in Arkansas; McDonald County, Missouri; 25 counties in Oklahoma. It was in force for 118 min.

The area

The outline as issued.

The facts

Issued
May 6, 2003, 10:32 AM CDT (15:32 UTC)
Expired
May 6, 2003, 12:30 PM CDT
In force
118 min
Issued by
the Storm Prediction Center
All 31 counties

Benton County, AR, Crawford County, AR, Franklin County, AR, Sebastian County, AR, Washington County, AR, McDonald County, MO, Adair County, OK, Atoka County, OK, Cherokee County, OK, Coal County, OK, Craig County, OK, Creek County, OK, Delaware County, OK, Haskell County, OK, Hughes County, OK, Latimer County, OK, LeFlore County, OK, Mayes County, OK, McIntosh County, OK, Muskogee County, OK, Nowata County, OK, Okfuskee County, OK, Okmulgee County, OK, Ottawa County, OK, Pittsburg County, OK, Pushmataha County, OK, Rogers County, OK, Sequoyah County, OK, Tulsa County, OK, Wagoner County, OK, Washington County, OK

The radar

The Tulsa radar (KINX), 66 km from the middle of the area, began a volume at 15:36 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

Norman, OK (KOUN), launched 12:00Z, 3.5 hours before the alert went out and 191 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, Norman, OK at 12:00Z on 2003-05-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 236 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, Norman, OK at 12:00Z on 2003-05-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 93 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
236 J/kg
Mixed-layer CIN
-453 J/kg
Mixed-layer LCL
2191 m above ground
0-6 km bulk shear
58 kt
0-1 km storm-relative helicity
93 m²/s²
0-3 km storm-relative helicity
103 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.9

Open this sounding in Storm Lab

The text

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

111 
ACUS11 KWNS 061533
SWOMCD
SPC MCD 061532 
ARZ000-MOZ000-OKZ000-061730-

MESOSCALE DISCUSSION 0787
NWS STORM PREDICTION CENTER NORMAN OK
1032 AM CDT TUE MAY 06 2003

AREAS AFFECTED...E OK/NW AR

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 061532Z - 061730Z

SCATTERED THUNDERSTORMS WILL LIKELY DEVELOP ACROSS ERN OK BY EARLY
AFTERNOON. CONVECTION WILL HAVE THE POTENTIAL FOR LARGE
HAIL...DAMAGING WINDS OR TORNADOES. TORNADO POTENTIAL WILL INCREASE
BY LATE AFTERNOON. WW MAY BE NECESSARY LATE THIS MORNING OR EARLY
THIS AFTERNOON ACROSS ERN OK/FAR NWRN AR.

STATIONARY FRONT EXTENDED ENE OF A SURFACE LOW OVER CNTRL OK.
DEWPOINTS WERE IN THE LOWER 70S S OF THE FRONT. TEMPERATURES AT 15Z
WERE ALREADY AROUND 80. MID-LEVEL JET WITH THE LEADING EDGE OF 
DRYER AIR CONTAINED STEEP LAPSE RATES OF 8.5 C/KG...WHILE SFC
HEATING IS INCREASING INSTABILITY. MLCAPE VALUES RANGED BETWEEN 3000
AND 4000 J/KG ACROSS ERN OK. RAPID DEVELOPMENT OF CONVECTION APPEARS
LIKELY ALONG THE INSTABILITY AXIS LATER THIS MORNING OR EARLY THIS
AFTERNOON. STRONG INSTABILITY...STEEP LAPSE RATES AND DEEP LAYER
SHEAR OF 55 KT SUGGEST STORMS WILL BECOME SUPERCELLULAR. CONVECTION
WILL HAVE THE POTENTIAL FOR LARGE HAIL AND OR DAMAGING WINDS. IN
ADDITION...LOW-LEVEL JET ACROSS ERN OK AND WRN AR WILL MAKE A FEW
TORNADOES LIKELY ACROSS ERN OK THIS AFTERNOON. WW WILL LIKELY BE
NECESSARY BY 19Z.

..BROYLES.. 05/06/2003

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

ATTN...WFO...LZK...SGF...SHV...TSA...OUN...

34089575 34329663 35529659 36299651 36729606 36919562
36919485 36849414 36399372 35069397 34159455

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 5, 9:05 PM CDTTornado WatchSPCPhillips7 hr
May 5, 10:58 PM CDTMesoscale DiscussionSPCBenton, Boone, Carroll, Fulton, Marion2 hr
May 6, 1:26 AM CDTMesoscale DiscussionSPCCrittenden, Lee, St. Francis3 hr
May 6, 1:50 AM CDTTornado WatchSPCClay, Craighead, Crittenden, Cross, Greene, Lee and 4 more6 hr
May 6, 5:06 AM CDTMesoscale DiscussionSPCCrittenden, Cross, Lee, Mississippi, Phillips, St. Francis3 hr
May 6, 11:40 AM CDTTornado WatchSPCBenton, Boone, Carroll, Crawford, Franklin, Johnson and 4 more7 hr
May 6, 3:05 PM CDTTornado WatchSPCLogan, Polk, Scott, Sebastian6 hr
May 6, 5:33 PM CDTMesoscale DiscussionSPCBaxter, Benton, Boone, Franklin, Fulton, Johnson and 6 more117 min
May 6, 6:55 PM CDTTornado WatchSPCBaxter, Benton, Boone, Carroll, Clark, Cleburne and 32 more5 hr
May 6, 6:49 AM CDTMesoscale DiscussionSPCBarton, Bates, Benton, Caldwell, Camden, Carroll and 27 more3 hr
May 6, 7:55 AM CDTSevere Thunderstorm WatchSPCBarton, Bates, Benton, Camden, Cass, Cedar and 22 more5 hr
May 6, 11:29 AM CDTMesoscale DiscussionSPCBarton, Bates, Benton, Cass, Cedar, Clay and 18 more2 hr
May 6, 11:55 AM CDTSevere Thunderstorm WatchSPCCole, Crawford, Dent, Franklin, Gasconade, Iron and 16 more4 hr
May 6, 2:15 PM CDTTornado WatchSPCBoone, Callaway, Camden, Carter, Cole, Cooper and 27 more5 hr
May 6, 3:42 PM CDTMesoscale DiscussionSPCBarton, Bates, Benton, Boone, Callaway, Camden and 20 more2 hr
May 6, 5:08 PM CDTMesoscale DiscussionSPCFranklin, Jefferson, Saint Charles, Saint Louis, Warren, City of Saint Louis2 hr
May 6, 5:40 PM CDTTornado WatchSPCBollinger, Butler, Cape Girardeau, Iron, Jefferson, Madison and 11 more6 hr
May 6, 6:35 PM CDTTornado WatchSPCBarry, Barton, Camden, Carter, Cedar, Christian and 31 more5 hr
May 6, 2:47 PM CDTMesoscale DiscussionSPCAtoka, Bryan, Choctaw, Coal, Haskell, Latimer and 5 more118 min

Nearby

Mesoscale Discussions in Oklahoma, 2003Mesoscale Discussions in Arkansas, 2003Mesoscale Discussions in Missouri, 2003Every mesoscale discussion in 2003

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.