Alert archive / Arkansas / Mesoscale Discussions in 2003
Mesoscale Discussion 558
The Storm Prediction Center issued this mesoscale discussion at Apr 24, 2003, 10:12 AM CDT for 26 counties in Arkansas. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 24, 2003, 10:12 AM CDT (15:12 UTC)
- Expired
- Apr 24, 2003, 12:15 PM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
All 26 counties
Arkansas County, AR, Cleburne County, AR, Conway County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Faulkner County, AR, Grant County, AR, Hot Spring County, AR, Independence County, AR, Jackson County, AR, Jefferson County, AR, Lawrence County, AR, Lee County, AR, Lonoke County, AR, Monroe County, AR, Phillips County, AR, Poinsett County, AR, Prairie County, AR, Pulaski County, AR, Saline County, AR, St. Francis County, AR, Stone County, AR, Van Buren County, AR, White County, AR, Woodruff County, AR
The watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Little Rock, AR (KLZK), launched 12:00Z, 3.2 hours before the alert went out and 178 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.
- Mixed-layer CAPE
- 29 J/kg
- Mixed-layer CIN
- -291 J/kg
- Mixed-layer LCL
- 788 m above ground
- 0-6 km bulk shear
- 61 kt
- 0-1 km storm-relative helicity
- 300 m²/s²
- 0-3 km storm-relative helicity
- 346 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 1.6
The text
As transmitted, in the capitals the NWS used until 2016.
000 ACUS11 KWNS 241513 SWOMCD SPC MCD 241512 ARZ000-MSZ000-241715- MESOSCALE DISCUSSION 0558 NWS STORM PREDICTION CENTER NORMAN OK 1012 AM CDT THU APR 24 2003 AREAS AFFECTED...CNTRL/ERN AR CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 241512Z - 241715Z SEVERE THREAT APPEARS TO BE INCREASING...WITH LARGE HAIL PRIMARY THREAT IN THE SHORT TERM. AREA IS BEING MONITORED FOR POSSIBILITY OF WW. LARGE-SCALE FORCING FOR UPWARD VERTICAL MOTION IN BAROCLINIC ZONE NORTH OF SURFACE WARM FRONT...NEAR THE TEXARKANA/EL DORADO AR INTO NORTH CENTRAL LOUISIANA...APPEARS TO BE INCREASING. DEEPENING CONVECTIVE DEVELOPMENT HAS BEEN EVIDENT PAST FEW HOURS...WITH FURTHER INTENSIFICATION LIKELY INTO THE AFTERNOON. SOUNDINGS INDICATE CAPE OF 1500 TO 3000 J/KG FOR PARCELS LIFTED ABOVE LOW-LEVEL INVERSION LAYER. SOUTHWESTERLY MID/UPPER FLOW HAS BEEN STRENGTHENING WITH NORTHEASTWARD PROGRESSION OF POLAR JET STREAK... CONTRIBUTING TO INCREASINGLY FAVORABLE SHEAR PROFILES FOR SUPERCELLS IN CLOUD BEARING LAYER. ..KERR.. 04/24/2003 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MEG...LZK... 34289338 34939284 35709266 36149138 35749022 34999032 34399085 33979206
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 23, 11:43 PM CDT | Mesoscale Discussion | SPC | Howard, Lafayette, Little River, Miller, Polk, Sevier | 2 hr |
| Apr 24, 2:41 AM CDT | Mesoscale Discussion | SPC | Columbia, Lafayette, Miller, Nevada, Ouachita | 2 hr |
| Apr 24, 12:47 PM CDT | Mesoscale Discussion | SPC | Arkansas, Bradley, Calhoun, Clark, Cleburne, Cleveland and 38 more | 3 hr |
| Apr 24, 1:00 PM CDT | Tornado Watch | SPC | Arkansas, Bradley, Calhoun, Clark, Cleveland, Columbia and 25 more | 7 hr |
| Apr 24, 2:05 PM CDT | Tornado Watch | SPC | Ashley, Chicot | 6 hr |
| Apr 24, 2:46 PM CDT | Mesoscale Discussion | SPC | Chicot | 119 min |
| Apr 24, 3:25 PM CDT | Tornado Watch | SPC | Baxter, Boone, Cleburne, Conway, Faulkner, Fulton and 19 more | 5 hr |
| Apr 24, 3:28 PM CDT | Mesoscale Discussion | SPC | Arkansas, Clark, Cleburne, Cleveland, Conway, Craighead and 32 more | 2 hr |
| Apr 24, 5:52 PM CDT | Mesoscale Discussion | SPC | Arkansas, Baxter, Boone, Clay, Cleburne, Cleveland and 36 more | 113 min |
| Apr 24, 6:35 PM CDT | Tornado Watch | SPC | Arkansas, Baxter, Clay, Cleburne, Cleveland, Conway and 33 more | 5 hr |
| Apr 24, 6:49 PM CDT | Mesoscale Discussion | SPC | Chicot | 56 min |
Nearby
Mesoscale 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.