Alert archive / Alabama / Mesoscale Discussions in 2003

Mesoscale Discussion 428

April 7, 200317 counties in Alabama; 5 counties in Georgia; Kemper County, Lauderdale County, Newton County, Mississippi

The Storm Prediction Center issued this mesoscale discussion at Apr 7, 2003, 4:49 AM CDT for 17 counties in Alabama; 5 counties in Georgia; Kemper County, Lauderdale County, Newton County, Mississippi. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
Apr 7, 2003, 4:49 AM CDT (09:49 UTC)
Expired
Apr 7, 2003, 7:45 AM CDT
In force
3 hr
Issued by
the Storm Prediction Center
All 25 counties

Autauga County, AL, Chambers County, AL, Chilton County, AL, Coosa County, AL, Dallas County, AL, Elmore County, AL, Greene County, AL, Hale County, AL, Lee County, AL, Lowndes County, AL, Macon County, AL, Marengo County, AL, Montgomery County, AL, Perry County, AL, Russell County, AL, Sumter County, AL, Tallapoosa County, AL, Harris County, GA, Meriwether County, GA, Muscogee County, GA, Talbot County, GA, Troup County, GA, Kemper County, MS, Lauderdale County, MS, Newton County, MS

The radar

The Birmingham radar (KBMX), 73 km from the middle of the area, began a volume at 09:53 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 nearest sounding before it

Birmingham, AL (KBMX), launched 00:00Z, 9.8 hours before the alert went out and 73 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, Birmingham, AL at 00:00Z on 2003-04-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 677 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, Birmingham, AL at 00:00Z on 2003-04-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 133 square meters per square second.1939587897Sfc1 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
677 J/kg
Mixed-layer CIN
-71 J/kg
Mixed-layer LCL
1007 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
133 m²/s²
0-3 km storm-relative helicity
175 m²/s²
Significant tornado parameter
0.3
Supercell composite
2.4

Open this sounding in Storm Lab

The text

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

375 
ACUS11 KWNS 070950
SWOMCD
SPC MCD 070949 
GAZ000-ALZ000-MSZ000-071245-

MESOSCALE DISCUSSION 0428
NWS STORM PREDICTION CENTER NORMAN OK
0449 AM CDT MON APR 07 2003

AREAS AFFECTED...CNTRL MS...CNTRL AL...W CNTRL GA

CONCERNING...SEVERE THUNDERSTORM POTENTIAL...HEAVY RAINFALL
110...

VALID 070949Z - 071245Z

HEAVY RAIN WILL PERSIST FROM PARTS OF CENTRAL MISSISSIPPI INTO
WEST CENTRAL GEORGIA THIS MORNING...WITH LOCALLY EXCESSIVE RAIN
TOTALS LIKELY.



STRONGER MID/UPPER FORCING FOR UPWARD VERTICAL MOTION IS NOW
SHIFTING FROM THE TENNESSEE VALLEY INTO THE CENTRAL APPALACHIANS.
 HOWEVER...BELT OF CONFLUENT LOW/MID-LEVEL FLOW IN ITS WAKE
ACROSS CENTRAL MISSISSIPPI/ALABAMA REMAINS FOCUS FOR VIGOROUS
CONVECTIVE DEVELOPMENT...SUPPORTING LIFT OF MOIST AND MODERATELY
UNSTABLE AIR.  CAPE FOR PARCELS LIFTED FROM JUST ABOVE SHALLOW
NEUTRAL TO STABLE SURFACE-BASED LAYER APPEARS TO BE ON THE ORDER
OF 1000 TO 1500 J/KG...IN KINEMATIC ENVIRONMENT SUPPORTIVE OF
SUPERCELLS.  DAMAGING WIND GUSTS/ISOLATED LARGE HAIL WILL REMAIN
POSSIBLE IN MOST INTENSE CELLS...BUT EXCESSIVE RAIN LIKELY HAS
BECOME PRIMARY THREAT AS CONVECTION CONTINUES TO TRAIN ALONG/JUST
NORTH OF A JACKSON/MERIDIAN/MONTGOMERY LINE.  MODELS SUGGEST
STRONGEST LOW-LEVEL FORCING WILL BEGIN TO SHIFT EASTWARD OUT OF
CENTRAL MISSISSIPPI BY 12Z...BUT HEAVY RAIN THREAT MAY PERSIST
ACROSS CENTRAL ALABAMA...WEST THROUGH NORTH OF MONTGOMERY...INTO
AREAS OF WEST CENTRAL GEORGIA...SOUTHWEST OF ATLANTA...THROUGH
THE 15-18Z TIME FRAME.

..KERR.. 04/07/2003

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

ATTN...WFO...FFC...BMX...MOB...JAN...

32208994 32718886 32898811 32878741 33008649 33248565
33248474 33148457 32658443 32488460 32288510 32228579
32138645 32098700 32008785 32048848 32158909

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 6, 8:13 PM CDTMesoscale DiscussionSPCBibb, Chilton, Choctaw, Dallas, Fayette, Greene and 8 more2 hr
Apr 6, 9:48 PM CDTMesoscale DiscussionSPCAutauga, Chilton, Choctaw, Clarke, Dallas, Hale and 6 more87 min
Apr 6, 10:15 PM CDTTornado WatchSPCAutauga, Butler, Choctaw, Clarke, Conecuh, Covington and 10 more5 hr
Apr 6, 11:39 PM CDTMesoscale DiscussionSPCAutauga, Butler, Choctaw, Clarke, Conecuh, Covington and 11 more2 hr
Apr 7, 1:51 AM CDTMesoscale DiscussionSPCBullock, Butler, Lowndes, Macon, Montgomery54 min
Apr 7, 2:55 AM CDTTornado WatchSPCAutauga, Barbour, Bullock, Chilton, Choctaw, Dallas and 13 more4 hr
Apr 7, 9:11 AM CDTMesoscale DiscussionSPCBarbour, Coffee, Conecuh, Covington, Crenshaw, Dale and 6 more3 hr
Apr 7, 9:40 AM CDTTornado WatchSPCBarbour, Bullock, Macon, Pike, Russell5 hr
Apr 7, 11:25 AM CDTMesoscale DiscussionSPCBaldwin, Butler, Clarke, Coffee, Conecuh, Covington and 6 more3 hr
Apr 7, 12:07 PM CDTMesoscale DiscussionSPCBaldwin, Butler, Clarke, Coffee, Conecuh, Covington and 6 more113 min
Apr 7, 12:22 PM CDTMesoscale DiscussionSPCBaldwin, Butler, Clarke, Coffee, Conecuh, Covington and 6 more113 min
Apr 7, 3:40 PM CDTSevere Thunderstorm WatchSPCBaldwin, Covington, Escambia, Mobile5 hr
Apr 7, 5:58 PM CDTMesoscale DiscussionSPCBaldwin, Escambia, Mobile2 hr
Apr 7, 10:05 AM CDTSevere Thunderstorm WatchSPCAmite, Forrest, George, Greene, Hancock, Harrison and 11 more6 hr
Apr 7, 11:02 AM CDTMesoscale DiscussionSPCForrest, Lamar, Pearl River, Perry, Stone3 hr
Apr 7, 2:13 PM CDTMesoscale DiscussionSPCHancock, Harrison, Pearl River, Perry, Stone3 hr
Apr 7, 2:36 PM CDTMesoscale DiscussionSPCHancock, Harrison, Pearl River, Perry, Stone114 min

Nearby

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