Alert archive / Louisiana / Mesoscale Discussions in 2011

Mesoscale Discussion 210

March 9, 20114 states

The Storm Prediction Center issued this mesoscale discussion at Mar 9, 2011, 1:28 AM CST for 4 states. It was in force for 92 min.

The area

The outline as issued.

The facts

Issued
Mar 9, 2011, 1:28 AM CST (07:28 UTC)
Expired
Mar 9, 2011, 3:00 AM CST
In force
92 min
Issued by
the Storm Prediction Center
All 97 counties

Choctaw County, AL, Mobile County, AL, Washington County, AL, Ashley County, AR, Union County, AR, Acadia Parish, LA, Allen Parish, LA, Ascension Parish, LA, Assumption Parish, LA, Avoyelles Parish, LA, Beauregard Parish, LA, Bienville Parish, LA, Calcasieu Parish, LA, Caldwell Parish, LA, Catahoula Parish, LA, Concordia Parish, LA, De Soto Parish, LA, East Baton Rouge Parish, LA, East Carroll Parish, LA, East Feliciana Parish, LA, Evangeline Parish, LA, Franklin Parish, LA, Grant Parish, LA, Iberville Parish, LA, Jackson Parish, LA, Jefferson Davis Parish, LA, Jefferson Parish, LA, Lafayette Parish, LA, LaSalle Parish, LA, Lincoln Parish, LA, Livingston Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Natchitoches Parish, LA, Orleans Parish, LA, Ouachita Parish, LA, Pointe Coupee Parish, LA, Rapides Parish, LA, Red River Parish, LA, Richland Parish, LA, Sabine Parish, LA, Saint Bernard Parish, LA, Saint Charles Parish, LA, Saint Helena Parish, LA, Saint James Parish, LA, Saint John the Baptist Parish, LA, Saint Landry Parish, LA, Saint Martin Parish, LA, Saint Tammany Parish, LA, Tangipahoa Parish, LA, Tensas Parish, LA, Union Parish, LA, Vernon Parish, LA, Washington Parish, LA, West Baton Rouge Parish, LA, West Carroll Parish, LA, West Feliciana Parish, LA, Winn Parish, LA, Adams County, MS, Amite County, MS, Claiborne 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, Issaquena County, MS, Jackson County, MS, Jasper County, MS, Jefferson County, MS, Jefferson Davis County, MS, Jones County, MS, Lamar County, MS, Lawrence County, MS, Lincoln County, MS, Madison County, MS, Marion County, MS, Newton County, MS, Pearl River County, MS, Perry County, MS, Pike County, MS, Rankin County, MS, Scott County, MS, Sharkey County, MS, Simpson County, MS, Smith County, MS, Stone County, MS, Walthall County, MS, Warren County, MS, Wayne County, MS, Wilkinson County, MS, Yazoo County, MS

The watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Jackson, MS (KJAN), launched 00:00Z, 7.5 hours before the alert went out and 151 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, Jackson, MS at 00:00Z on 2011-03-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 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, Jackson, MS at 00:00Z on 2011-03-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 542 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
600 m above ground
0-6 km bulk shear
65 kt
0-1 km storm-relative helicity
542 m²/s²
0-3 km storm-relative helicity
664 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

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

808 
ACUS11 KWNS 090729
SWOMCD
SPC MCD 090728
ALZ000-MSZ000-LAZ000-ARZ000-TXZ000-090900-

MESOSCALE DISCUSSION 0210
NWS STORM PREDICTION CENTER NORMAN OK
0128 AM CST WED MAR 09 2011

AREAS AFFECTED...LA...MS...FAR SRN AR...SW AL

CONCERNING...TORNADO WATCH 44...

VALID 090728Z - 090900Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 44 CONTINUES.

THE SEVERE THREAT ACROSS WW 44 WILL CONTINUE LATE TONIGHT AS CELLS
MOVE EWD INTO SCNTRL MS AND SRN LA. A FEW TORNADOES MAY OCCUR WITH
DISCRETE CELLS THAT INITIATE AND PERSIST AHEAD OF A DEVELOPING
SQUALL-LINE. THE WIND DAMAGE THREAT WILL LIKELY INCREASE AS STORMS
CONGEAL INTO A LINEAR MCS. ANOTHER TORNADO WATCH WILL BE NEEDED
BEFORE 09Z TO REPLACE THE CURRENT WW.

LATEST SFC ANALYSIS SHOWS A SFC LOW OVER THE ARKLATEX WITH A WARM
FRONT EXTENDING EWD ACROSS NRN LA INTO SCNTRL MS. SEVERAL BOWING
LINE-SEGMENTS ARE ONGOING NEAR AND TO THE SOUTH OF THE BOUNDARY IN
SW MS AND CNTRL LA ON THE NRN EDGE OF THE WARM SECTOR. SFC DEWPOINTS
IN THE WARM SECTOR ARE IN THE MID TO UPPER 60S F WITH MLCAPE VALUES
ESTIMATED IN THE 500 TO 1500 J/KG RANGE. AS THE STORMS MOVE EWD
ALONG THE BOUNDARY...VORTICITY WILL BE ENHANCED WITH STORMS THAT
INTERACT WITH THE WARM FRONT WHICH COMBINED WITH 0-3 KM STORM
RELATIVE HELICITY OF 400 M2/S2 ESTIMATED BY WSR-88D VWPS SHOULD BE
FAVORABLE FOR ROTATING STORMS AND POSSIBLY A FEW TORNADOES. IN
ADDITION...WSR-88D VWPS ESTIMATE WINDS JUST ABOVE THE SFC IN THE 40
TO 50 KT RANGE SUGGESTING A WIND DAMAGE THREAT WILL EXIST ESPECIALLY
WITH THE FASTER MOVING BOWING LINE-SEGMENTS.

..BROYLES.. 03/09/2011

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

ATTN...WFO...BMX...MOB...JAN...LIX...LZK...LCH...SHV...

LAT...LON   30059119 30049148 30029156 30109169 30069186 30059206
            30099215 30069234 30019241 30069257 30019284 30079369
            30519373 31079356 31329365 31589381 31929395 32119408
            32249398 32349380 32209365 32249349 32459340 32459321
            32609318 32609291 32789281 32889267 33079268 33079298
            33429300 33399267 33209217 33409199 33379148 33039143
            33019094 33179087 33119066 32989064 32959043 33029042
            32868999 32888980 32628975 32578893 32278890 32238846
            32328845 32298799 32028809 31848819 31668806 31458791
            30968796 30348811 30418837 29898836 29898846 29388878
            29928935 29748953 29638949 29888993 29859008 29659007
            29439000 29219006 29339007 29539012 29639021 29719034
            29819041 29839061 29869080 29749095 29679108 29779124
            29839137 30059119

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 8, 7:37 PM CSTTornado WatchSPCChoctaw, Mobile, Washington7 hr
Mar 9, 2:39 AM CSTTornado WatchSPCBaldwin, Choctaw, Clarke, Mobile, Monroe, Washington and 1 more5 hr
Mar 9, 6:28 AM CSTMesoscale DiscussionSPCChoctaw, Mobile, Washington92 min
Mar 9, 7:26 AM CSTTornado WatchSPCBaldwin, Butler, Conecuh, Covington, Crenshaw, Escambia and 2 more6 hr
Mar 9, 8:32 AM CSTMesoscale DiscussionSPCCoffee, Dale, Geneva, Henry, Houston28 min
Mar 9, 8:39 AM CSTTornado WatchSPCCoffee, Dale, Geneva, Henry, Houston7 hr
Mar 9, 9:31 AM CSTMesoscale DiscussionSPCBaldwin, Butler, Coffee, Conecuh, Covington, Crenshaw and 7 more59 min
Mar 8, 6:27 PM CSTMesoscale DiscussionSPCBradley, Calhoun, Columbia, Hempstead, Howard, Lafayette and 6 more63 min
Mar 8, 9:40 PM CSTMesoscale DiscussionSPCColumbia, Lafayette, Union65 min
Mar 9, 4:39 AM CSTMesoscale DiscussionSPCAscension, Assumption, East Baton Rouge, Iberville, Livingston, Orleans and 9 more66 min

Nearby

Mesoscale Discussions in Louisiana, 2011Mesoscale Discussions in Mississippi, 2011Mesoscale Discussions in Alabama, 2011Every mesoscale discussion in 2011

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.