Alert archive / Oklahoma / Mesoscale Discussions in 2003

Mesoscale Discussion 672

May 1, 200316 counties in Arkansas; 18 counties in Oklahoma

The Storm Prediction Center issued this mesoscale discussion at May 1, 2003, 6:58 PM CDT for 16 counties in Arkansas; 18 counties in Oklahoma. It was in force for 92 min.

The area

The outline as issued.

The facts

Issued
May 1, 2003, 6:58 PM CDT (23:58 UTC)
Expired
May 1, 2003, 8:30 PM CDT
In force
92 min
Issued by
the Storm Prediction Center
All 34 counties

Benton County, AR, Carroll County, AR, Crawford County, AR, Franklin County, AR, Hempstead County, AR, Howard County, AR, Johnson County, AR, Logan County, AR, Madison County, AR, Montgomery County, AR, Pike County, AR, Polk County, AR, Scott County, AR, Sebastian County, AR, Sevier County, AR, Washington County, AR, Adair County, OK, Cherokee County, OK, Choctaw County, OK, Delaware County, OK, Haskell County, OK, Latimer County, OK, LeFlore County, OK, Mayes County, OK, McCurtain County, OK, McIntosh County, OK, Muskogee County, OK, Okmulgee County, OK, Pittsburg County, OK, Pushmataha County, OK, Rogers County, OK, Sequoyah County, OK, Tulsa County, OK, Wagoner County, OK

The radar

The Western Arkansas radar (KSRX), 42 km from the middle of the area, began a volume at 00:04 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

Springfield, MO (KSGF), launched 12:00Z, 12.0 hours before the alert went out and 220 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, Springfield, MO at 12:00Z on 2003-05-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Springfield, MO at 12:00Z on 2003-05-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -340 square meters per square second.193958Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
816 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
-340 m²/s²
0-3 km storm-relative helicity
-135 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.

786 
ACUS11 KWNS 012358
SWOMCD
SPC MCD 012358 
ARZ000-OKZ000-TXZ000-020130-

MESOSCALE DISCUSSION 0672
NWS STORM PREDICTION CENTER NORMAN OK
0658 PM CDT THU MAY 01 2003

AREAS AFFECTED...ERN OK/WRN AR

CONCERNING...TORNADO WATCH 202...

VALID 012358Z - 020130Z

IN ADDITION TO LARGE HAIL...ISOLATED TORNADO THREAT WILL CONTINUE
ACROSS WW0200 FOR THE NEXT FEW HOURS.

LATEST TULSA RADAR DATA INDICATE SEVERAL SUPERCELLS IN PROGRESS OVER
ERN OK. THE MOST INTENSE STORM WHICH HAS A HISTORY OF PRODUCING
TORNADOES WAS OVER NRN SEQUOYAH COUNTY IN ERN OK MOVING SEWD AT
20KTS. THIS STORM IS LOCATED JUST E OF A SURFACE LOW...PER MESONET
DATA...WITH THE ADDITIONAL STRONG TO SEVERE STORMS LOCATED JUST E OF
A PRE-FRONTAL TROUGH WHICH EXTENDS SWD FROM THE LOW TO JUST E OF
DUA.

THE AIRMASS TO THE E OF SURFACE LOW AND ATTENDANT TROUGH REMAINS
VERY UNSTABLE WITH MLCAPES OF 2500-3500 J/KG. THIS IN COMBINATION
WITH 0-6KM AGL SHEAR OF 40-45KTS WILL CONTINUE TO SUPPORT SUPERCELLS
ACROSS THE WW AREA. THE GREATEST TORNADO THREAT WILL REMAIN ACROSS
FAR ERN OK INTO WRN AR INVOF THE SURFACE LOW WHERE BACKED NEAR
SURFACE WINDS ARE RESULTING IN 0-1KM SRH VALUES OF 100-150 M2/S2.
MOREOVER...RELATIVELY LOW LCL HEIGHTS /AOB 1KM/ ARE ALSO
CONTRIBUTING TO FAVORABLE LOW-LEVEL CONDITIONS FOR ISOLATED
TORNADOES.   

..MEAD.. 05/01/2003

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

ATTN...WFO...LZK...SHV...TSA...FWD...OUN...

34219585 35039590 35729598 36279598 36439598 36479598
36459553 36419478 36439422 36459386 36439363 36439349
36399349 35799347 35209345 34479345 34059342 33849343
33779344 33739348 33749454 33759537 33779566 33759582
33759585 33939585

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 1, 7:51 AM CDTMesoscale DiscussionSPCBaxter, Clay, Fulton, Izard, Randolph, Searcy and 1 more114 min
May 1, 9:35 AM CDTSevere Thunderstorm WatchSPCClay, Craighead, Greene5 hr
May 1, 11:23 AM CDTMesoscale DiscussionSPCCrittenden, Cross, Mississippi, St. Francis2 hr
May 1, 2:13 PM CDTMesoscale DiscussionSPCHoward, Little River, Polk, Scott, Sevier3 hr
May 1, 2:55 PM CDTTornado WatchSPCLittle River5 hr
May 1, 3:45 PM CDTTornado WatchSPCBenton, Carroll, Crawford, Franklin, Howard, Johnson and 9 more5 hr
May 1, 6:10 PM CDTMesoscale DiscussionSPCArkansas, Dallas, Hempstead, Jefferson, Lee, Little River and 3 more95 min
Apr 30, 7:30 PM CDTSevere Thunderstorm WatchSPCGarfield, Grant, Kay, Logan, Noble, Osage and 2 more6 hr
Apr 30, 8:17 PM CDTMesoscale DiscussionSPCAlfalfa, Blaine, Caddo, Canadian, Comanche, Cotton and 14 more88 min
Apr 30, 9:52 PM CDTMesoscale DiscussionSPCGarfield, Grant, Kay, Logan, Noble, Osage and 2 more83 min
Apr 30, 11:47 PM CDTMesoscale DiscussionSPCGarfield, Grant, Kay, Logan, Noble, Osage and 2 more118 min
May 1, 12:10 AM CDTSevere Thunderstorm WatchSPCCraig, Garfield, Grant, Kay, Noble, Nowata and 4 more5 hr
May 1, 2:27 AM CDTMesoscale DiscussionSPCCraig, Delaware, Mayes, Nowata, Osage, Ottawa and 2 more2 hr
May 1, 10:55 AM CDTMesoscale DiscussionSPCBryan, Coal, Johnston, Love, Marshall2 hr

Nearby

Mesoscale Discussions in Oklahoma, 2003Mesoscale Discussions in Arkansas, 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.