Alert archive / Georgia / Mesoscale Discussions in 2003

Mesoscale Discussion 944

May 11, 20035 states

The Storm Prediction Center issued this mesoscale discussion at May 11, 2003, 12:20 PM CDT for 5 states. It was in force for 115 min.

The area

The outline as issued.

The facts

Issued
May 11, 2003, 12:20 PM CDT (17:20 UTC)
Expired
May 11, 2003, 2:15 PM CDT
In force
115 min
Issued by
the Storm Prediction Center
All 91 counties

Baldwin County, AL, Barbour County, AL, Bullock County, AL, Butler County, AL, Clarke County, AL, Coffee County, AL, Conecuh County, AL, Covington County, AL, Crenshaw County, AL, Dale County, AL, Escambia County, AL, Geneva County, AL, Henry County, AL, Houston County, AL, Lee County, AL, Lowndes County, AL, Macon County, AL, Mobile County, AL, Monroe County, AL, Montgomery County, AL, Pike County, AL, Russell County, AL, Washington County, AL, Wilcox County, AL, Escambia County, FL, Santa Rosa County, FL, Appling County, GA, Baker County, GA, Ben Hill County, GA, Bibb County, GA, Bleckley County, GA, Calhoun County, GA, Chattahoochee County, GA, Clay County, GA, Crawford County, GA, Crisp County, GA, Dodge County, GA, Dooly County, GA, Dougherty County, GA, Early County, GA, Harris County, GA, Houston County, GA, Irwin County, GA, Jeff Davis County, GA, Lamar County, GA, Laurens County, GA, Lee County, GA, Macon County, GA, Marion County, GA, Monroe County, GA, Montgomery County, GA, Muscogee County, GA, Peach County, GA, Pulaski County, GA, Quitman County, GA, Randolph County, GA, Schley County, GA, Stewart County, GA, Sumter County, GA, Talbot County, GA, Taylor County, GA, Telfair County, GA, Terrell County, GA, Turner County, GA, Twiggs County, GA, Upson County, GA, Webster County, GA, Wheeler County, GA, Wilcox County, GA, Worth County, GA, Ascension Parish, LA, Livingston Parish, LA, Orleans Parish, LA, Saint Bernard Parish, LA, Saint John the Baptist Parish, LA, Saint Tammany Parish, LA, Tangipahoa Parish, LA, Washington Parish, LA, Forrest County, MS, George County, MS, Greene County, MS, Hancock County, MS, Harrison County, MS, Jackson County, MS, Lamar County, MS, Marion County, MS, Pearl River County, MS, Perry County, MS, Stone County, MS, Walthall County, MS, Wayne County, MS

The radar

The Mobile radar (KMOB), 85 km from the middle of the area, began a volume at 17:23 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

Slidell Radar S, LA (KSIL), launched 12:00Z, 5.3 hours before the alert went out and 232 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, Slidell Radar S, LA at 12:00Z on 2003-05-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1481 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, Slidell Radar S, LA at 12:00Z on 2003-05-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 88 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
1481 J/kg
Mixed-layer CIN
-49 J/kg
Mixed-layer LCL
606 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
88 m²/s²
0-3 km storm-relative helicity
188 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.9

Open this sounding in Storm Lab

The text

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

865 
ACUS11 KWNS 111721
SWOMCD
SPC MCD 111720 
GAZ000-ALZ000-FLZ000-MSZ000-LAZ000-111915-

MESOSCALE DISCUSSION 0944
NWS STORM PREDICTION CENTER NORMAN OK
1220 PM CDT SUN MAY 11 2003

AREAS AFFECTED...SERN LA....SRN MS...SRN AND CENTRAL AL/GA...FAR
NWRN FL

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 111720Z - 111915Z

LARGE SCALE FORCING HAS INCREASED OVER THE AREA AHEAD OF ADVANCING
SHORTWAVE TROUGH MOVING OUT OF TX PER WV IMAGERY. A SUBTLE UPPER
LEVEL SPEED MAX APPEARS TO BE MOVING ACROSS LA AHEAD OF THE TROUGH
AND HAS AIDED IN CONVECTIVE DEVELOPMENT OVER CENTRAL LA. AN OUTFLOW
BOUNDARY EXTENDING FROM 30 S OF MEI ENEWD TO 40 S OF FFC AS OF 17Z.
EXPECT ADDITIONAL STRONG TO SEVERE CONVECTIVE DEVELOPMENT ALONG THIS
BOUNDARY OVER THE NEXT FEW HOURS...AS INHIBITION IS WEAKENING. 35 TO
40 KTS OF SFC-6 KM SHEAR ALONG WITH MODERATE INSTABILITY /2000 J/KG
OF MLCAPE/ WILL FAVOR THE POTENTIAL FOR LARGE HAIL. IF ADDITIONAL
EARLY MORNING ELEVATED CONVECTION CAN ACCELERATE AND MOVE INTO THE
WARM SECTOR A DAMAGING WIND THREAT WILL INCREASE..ESPECIALLY OVER
ERN AL INTO CENTRAL GA.

A WW MAY BE NEEDED FOR THIS AREA IN THE NEXT HOUR.

..CROSBIE.. 05/11/2003

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

ATTN...WFO...CHS...JAX...FFC...TAE...BMX...MOB...JAN...LIX...

29738959 30329134 31249017 33258385 31778202 31058552

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 10, 11:20 PM CDTTornado WatchSPCColbert, Franklin, Lauderdale6 hr
May 11, 1:46 AM CDTMesoscale DiscussionSPCColbert, Lauderdale89 min
May 11, 3:10 AM CDTMesoscale DiscussionSPCBibb, Blount, Cullman, DeKalb, Fayette, Greene and 17 more95 min
May 11, 3:20 AM CDTSevere Thunderstorm WatchSPCBlount, Cullman, Fayette, Jackson, Jefferson, Lamar and 8 more5 hr
May 11, 5:22 AM CDTMesoscale DiscussionSPCBlount, Cullman, Fayette, Jackson, Jefferson, Lamar and 8 more83 min
May 11, 1:15 PM CDTSevere Thunderstorm WatchSPCAutauga, Barbour, Bullock, Butler, Chambers, Chilton and 20 more6 hr
May 11, 3:00 PM CDTMesoscale DiscussionSPCAutauga, Barbour, Bullock, Butler, Choctaw, Clarke and 14 more2 hr
May 10, 10:04 PM CDTMesoscale DiscussionSPCAlcorn, Benton, Marshall, Panola, Tippah116 min

Nearby

Mesoscale Discussions in Georgia, 2003Mesoscale Discussions in Alabama, 2003Mesoscale Discussions in Mississippi, 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.