Alert archive / Mississippi / Mesoscale Discussions in 2012
Mesoscale Discussion 2190
The Storm Prediction Center issued this mesoscale discussion at Dec 20, 2012, 9:56 AM CST for 4 states. It was in force for 64 min.
The area
The outline as issued.
The facts
- Issued
- Dec 20, 2012, 9:56 AM CST (15:56 UTC)
- Expired
- Dec 20, 2012, 11:00 AM CST
- In force
- 64 min
- Issued by
- the Storm Prediction Center
All 80 counties
Autauga County, AL, Baldwin County, AL, Bibb County, AL, Butler County, AL, Chambers County, AL, Chilton County, AL, Choctaw County, AL, Clarke County, AL, Conecuh County, AL, Coosa County, AL, Covington County, AL, Crenshaw County, AL, Dallas County, AL, Elmore County, AL, Escambia County, AL, Greene County, AL, Hale County, AL, Lowndes County, AL, Macon County, AL, Marengo County, AL, Mobile County, AL, Monroe County, AL, Montgomery County, AL, Perry County, AL, Sumter County, AL, Tallapoosa County, AL, Washington County, AL, Wilcox County, AL, Escambia County, FL, Santa Rosa County, FL, Ascension Parish, LA, East Baton Rouge Parish, LA, East Feliciana Parish, LA, Iberville Parish, LA, Livingston Parish, LA, Saint Helena Parish, LA, Saint John the Baptist Parish, LA, Saint Martin Parish, LA, Saint Tammany Parish, LA, Tangipahoa Parish, LA, Washington Parish, LA, West Baton Rouge Parish, LA, Amite County, MS, Attala County, MS, Clarke County, MS, Copiah County, MS, Covington County, MS, Forrest County, MS, Franklin County, MS, George County, MS, Greene County, MS, Hancock County, MS, Harrison County, MS, Hinds County, MS, Jackson County, MS, Jasper County, MS, Jefferson Davis County, MS, Jones County, MS, Kemper County, MS, Lamar County, MS, Lauderdale County, MS, Lawrence County, MS, Leake County, MS, Lincoln County, MS, Madison County, MS, Marion County, MS, Neshoba County, MS, Newton County, MS, Noxubee County, MS, Pearl River County, MS, Perry County, MS, Pike County, MS, Rankin County, MS, Scott County, MS, Simpson County, MS, Smith County, MS, Stone County, MS, Walthall County, MS, Wayne County, MS, Winston County, MS
The radar
The Jackson/Brandon,MS radar (KDGX), 117 km from the middle of the area, began a volume at 15:59 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
Jackson, MS (KJAN), launched 12:00Z, 3.9 hours before the alert went out and 127 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
- 653 J/kg
- Mixed-layer CIN
- -1 J/kg
- Mixed-layer LCL
- 587 m above ground
- 0-6 km bulk shear
- 69 kt
- 0-1 km storm-relative helicity
- 247 m²/s²
- 0-3 km storm-relative helicity
- 240 m²/s²
- Significant tornado parameter
- 1.1
- Supercell composite
- 5.1
The text
As transmitted, in the capitals the NWS used until 2016.
752 ACUS11 KWNS 201557 SWOMCD SPC MCD 201556 GAZ000-ALZ000-FLZ000-MSZ000-LAZ000-201700- MESOSCALE DISCUSSION 2190 NWS STORM PREDICTION CENTER NORMAN OK 0956 AM CST THU DEC 20 2012 AREAS AFFECTED...SERN MS...AL...WRN FL PANHANDLE CONCERNING...TORNADO WATCH 689... VALID 201556Z - 201700Z THE SEVERE WEATHER THREAT FOR TORNADO WATCH 689 CONTINUES. SUMMARY...SEVERE THREAT WILL SPREAD FROM WEST TO EAST ACROSS THE CENTRAL GULF STATES THIS MORNING WITH THE GREATER TORNADO THREAT SHIFTING ACROSS SRN AL/FL PANHANDLE. DISCUSSION...WRN MOST SQUALL LINE AHEAD OF THE COLD FRONT IS ADVANCING EWD AT ROUGHLY 35-40KT AND GIVEN THIS MOTION IT SHOULD APPROACH THE ERN PART OF WW689 BY 1730Z. ERN MOST PRE-FRONTAL CORRIDOR OF CONVECTION WITH EMBEDDED SUPERCELLS IS MOVING A BIT SLOWER AND WILL LIKELY BE OVERCOME BY FASTER MOVING FRONTAL SQUALL LINE ACROSS THE CNTRL FL PANHANDLE. GREATEST SEVERE RISK APPEARS TO BE WITH ROTATING STRUCTURES THAT ARE ROOTED WITHIN MORE MOIST/BUOYANT AIRMASS LOCATED WITHIN ROUGHLY 75 MI OF COAST. ..DARROW.. 12/20/2012 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FFC...BMX...MOB...JAN...LIX...LCH... LAT...LON 33199004 33208519 30108702 30109172 33199004
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 20, 4:08 AM CST | Mesoscale Discussion | SPC | Choctaw, Colbert, Fayette, Franklin, Greene, Lamar and 5 more | 67 min |
| Dec 20, 4:23 AM CST | Tornado Watch | SPC | Autauga, Baldwin, Barbour, Bibb, Bullock, Butler and 34 more | 9 hr |
| Dec 20, 7:09 AM CST | Mesoscale Discussion | SPC | Autauga, Baldwin, Bibb, Butler, Chilton, Choctaw and 22 more | 96 min |
| Dec 20, 8:49 AM CST | Mesoscale Discussion | SPC | Dale, Geneva, Henry, Houston | 56 min |
| Dec 20, 9:19 AM CST | Tornado Watch | SPC | Coffee, Dale, Geneva, Henry, Houston | 9 hr |
| Dec 20, 1:31 PM CST | Mesoscale Discussion | SPC | Barbour, Coffee, Dale, Geneva, Henry, Houston and 1 more | 59 min |
| Dec 20, 5:22 PM CST | Mesoscale Discussion | SPC | Alachua, Baker, Bradford, Clay, Columbia, Dixie and 7 more | 53 min |
| Dec 19, 9:56 PM CST | Severe Thunderstorm Watch | SPC | Bossier, Caddo, De Soto | 5 hr |
| Dec 19, 11:55 PM CST | Mesoscale Discussion | SPC | Allen, Avoyelles, Beauregard, Bienville, Bossier, Caddo and 28 more | 95 min |
| Dec 20, 12:50 AM CST | Mesoscale Discussion | SPC | Bienville, Caldwell, Claiborne, East Carroll, Franklin, Jackson and 10 more | 55 min |
| Dec 20, 1:07 AM CST | Severe Thunderstorm Watch | SPC | Avoyelles, Bienville, Caldwell, Catahoula, Claiborne, Concordia and 20 more | 5 hr |
Nearby
Mesoscale Discussions in Mississippi, 2012Mesoscale Discussions in Alabama, 2012Mesoscale Discussions in Louisiana, 2012Every mesoscale discussion in 2012
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.