Alert archive / Louisiana / Mesoscale Discussions in 2007

Mesoscale Discussion 985

June 3, 200738 parishes in Louisiana; 13 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Jun 3, 2007, 3:13 PM CDT for 38 parishes in Louisiana; 13 counties in Mississippi. It was in force for 62 min.

The area

The outline as issued.

The facts

Issued
Jun 3, 2007, 3:13 PM CDT (20:13 UTC)
Expired
Jun 3, 2007, 4:15 PM CDT
In force
62 min
Issued by
the Storm Prediction Center
All 51 counties

Acadia Parish, LA, Allen Parish, LA, Ascension Parish, LA, Assumption Parish, LA, Avoyelles Parish, LA, Calcasieu Parish, LA, Catahoula Parish, LA, Concordia Parish, LA, East Baton Rouge Parish, LA, East Feliciana Parish, LA, Evangeline Parish, LA, Grant Parish, LA, Iberia Parish, LA, Iberville Parish, LA, Jefferson Davis Parish, LA, Jefferson Parish, LA, Lafayette Parish, LA, Lafourche Parish, LA, LaSalle Parish, LA, Livingston Parish, LA, Orleans Parish, LA, Pointe Coupee Parish, LA, Rapides 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, St. Mary Parish, LA, Tangipahoa Parish, LA, Tensas Parish, LA, Terrebonne Parish, LA, Vermilion Parish, LA, Washington Parish, LA, West Baton Rouge Parish, LA, West Feliciana Parish, LA, Adams County, MS, Amite County, MS, Claiborne County, MS, Franklin County, MS, Hancock County, MS, Jefferson County, MS, Lawrence County, MS, Lincoln County, MS, Marion County, MS, Pearl River County, MS, Pike County, MS, Walthall County, MS, Wilkinson 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

Lake Charles Mun, LA (KLCH), launched 12:00Z, 8.2 hours before the alert went out and 180 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, Lake Charles Mun, LA at 12:00Z on 2007-06-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1497 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, Lake Charles Mun, LA at 12:00Z on 2007-06-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 68 square meters per square second.19395878Sfc1 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
1497 J/kg
Mixed-layer CIN
-7 J/kg
Mixed-layer LCL
623 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
68 m²/s²
0-3 km storm-relative helicity
52 m²/s²
Significant tornado parameter
0.5
Supercell composite
3.6

Open this sounding in Storm Lab

The text

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

000 
ACUS11 KWNS 032013
SWOMCD
SPC MCD 032013 
LAZ000-MSZ000-032115-

MESOSCALE DISCUSSION 0985
NWS STORM PREDICTION CENTER NORMAN OK
0313 PM CDT SUN JUN 03 2007

AREAS AFFECTED...CNTRL/SRN LA...SWRN MS

CONCERNING...SEVERE THUNDERSTORM WATCH 337...

VALID 032013Z - 032115Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 337
CONTINUES.

LONG-LIVED LINEAR/TRAILING STRATIFORM MCS WITH A HISTORY OF WIND
DAMAGE ACROSS ERN TX/WRN LA WILL CONTINUE TO MARCH E/SEWD THROUGH
THE ERN HALF OF WW 337 OVER THE NEXT FEW HOURS. IF OVERALL INTENSITY
APPEARS TO BE MAINTAINED...A DOWNSTREAM WW WILL LIKELY BE ISSUED
ACROSS ERN LA/SWRN MS WITHIN THE HOUR.

AS OF 2005Z...THE LEADING EDGE OF THE LINEAR MCS WAS ROUGHLY FROM 40
W MLU SWD TO ESF ARCING SWWD TO NEAR LCH. OVERALL RADAR REFLECTIVITY
TRENDS HAVE SHOWN A DOWNWARD/INCREASINGLY DISORGANIZED TREND OVER
THE PAST HOUR...WITH CORRESPONDING WARMING OF CONVECTIVE CLOUD TOPS
ON IR IMAGERY. THIS APPEARS TO CORRELATE WITH THE LINE MOVING E OF
THE RICHEST LOW-LEVEL THETA-E AXIS. STILL...WITH TEMPERATURES IN THE
UPPER 80S AND DEW POINTS IN THE MID TO UPPER 60S AHEAD OF THE
LINE...CONVECTIVE INTENSITY MAY BE ABLE TO MAINTAIN ITSELF IN
POSSIBLY MORE DISORGANIZED LINE SEGMENTS. DAMAGING WINDS WILL LIKELY
REMAIN THE MAIN THREAT.

..GRAMS.. 06/03/2007

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

ATTN...WFO...JAN...LIX...LCH...SHV...

32089178 32019087 31518997 30828951 29748939 29238999
29399133 29649254 29979342 30469344 31379289 31999247

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 3, 11:47 AM CDTMesoscale DiscussionSPCAllen, Beauregard, Calcasieu, De Soto, Grant, Jefferson Davis and 4 more58 min
Jun 3, 12:22 PM CDTSevere Thunderstorm WatchSPCAcadia, Allen, Avoyelles, Beauregard, Bossier, Caddo and 19 more6 hr
Jun 3, 3:35 PM CDTSevere Thunderstorm WatchSPCAscension, Assumption, Catahoula, Concordia, East Baton Rouge, East Feliciana and 11 more3 hr
Jun 3, 5:48 PM CDTMesoscale DiscussionSPCAcadia, Allen, Ascension, Assumption, Avoyelles, Beauregard and 41 more87 min

Nearby

Mesoscale Discussions in Louisiana, 2007Mesoscale Discussions in Mississippi, 2007Every mesoscale discussion in 2007

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.