Alert archive / Texas / Mesoscale Discussions in 2012

Mesoscale Discussion 2101

November 5, 201227 parishes in Louisiana; Wilkinson County, Mississippi; 55 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Nov 5, 2012, 1:19 PM CST for 27 parishes in Louisiana; Wilkinson County, Mississippi; 55 counties in Texas. It was in force for 86 min.

The area

The outline as issued.

The facts

Issued
Nov 5, 2012, 1:19 PM CST (19:19 UTC)
Expired
Nov 5, 2012, 2:45 PM CST
In force
86 min
Issued by
the Storm Prediction Center
Chance of a watch
40%
All 83 counties

Acadia Parish, LA, Allen Parish, LA, Ascension Parish, LA, Assumption Parish, LA, Avoyelles Parish, LA, Beauregard Parish, LA, Calcasieu Parish, LA, Cameron Parish, LA, East Baton Rouge Parish, LA, East Feliciana Parish, LA, Evangeline Parish, LA, Iberia Parish, LA, Iberville Parish, LA, Jefferson Davis Parish, LA, Lafayette Parish, LA, Livingston Parish, LA, Pointe Coupee Parish, LA, Rapides Parish, LA, Sabine Parish, LA, Saint James Parish, LA, Saint Landry Parish, LA, Saint Martin Parish, LA, St. Mary Parish, LA, Vermilion Parish, LA, Vernon Parish, LA, West Baton Rouge Parish, LA, West Feliciana Parish, LA, Wilkinson County, MS, Angelina County, TX, Austin County, TX, Bastrop County, TX, Bell County, TX, Blanco County, TX, Brazoria County, TX, Brazos County, TX, Burleson County, TX, Caldwell County, TX, Calhoun County, TX, Chambers County, TX, Colorado County, TX, Comal County, TX, DeWitt County, TX, Falls County, TX, Fayette County, TX, Fort Bend County, TX, Galveston County, TX, Goliad County, TX, Gonzales County, TX, Grimes County, TX, Guadalupe County, TX, Hardin County, TX, Harris County, TX, Hays County, TX, Houston County, TX, Jackson County, TX, Jasper County, TX, Jefferson County, TX, Lavaca County, TX, Lee County, TX, Leon County, TX, Liberty County, TX, Madison County, TX, Matagorda County, TX, Milam County, TX, Montgomery County, TX, Nacogdoches County, TX, Newton County, TX, Orange County, TX, Polk County, TX, Robertson County, TX, Sabine County, TX, San Augustine County, TX, San Jacinto County, TX, Travis County, TX, Trinity County, TX, Tyler County, TX, Victoria County, TX, Walker County, TX, Waller County, TX, Washington County, TX, Wharton County, TX, Williamson County, TX, Wilson County, TX

The radar

The Houston radar (KHGX), 47 km from the middle of the area, began a volume at 19:25 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

Lake Charles Mun, LA (KLCH), launched 12:00Z, 7.3 hours before the alert went out and 154 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 2012-11-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 126 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 2012-11-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 80 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
126 J/kg
Mixed-layer CIN
-139 J/kg
Mixed-layer LCL
665 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
80 m²/s²
0-3 km storm-relative helicity
112 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.9

Open this sounding in Storm Lab

The text

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

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Nov 5, 2:08 PM CSTSevere Thunderstorm WatchSPCBeauregard, Calcasieu, Cameron7 hr
Nov 5, 4:43 PM CSTMesoscale DiscussionSPCAcadia, Ascension, Assumption, East Baton Rouge, East Feliciana, Evangeline and 22 more92 min
Nov 5, 5:25 PM CSTMesoscale DiscussionSPCAllen, Beauregard, Calcasieu, Cameron, Jefferson Davis95 min
Nov 5, 5:29 PM CSTSevere Thunderstorm WatchSPCAcadia, Allen, Ascension, Assumption, East Baton Rouge, East Feliciana and 26 more6 hr

Nearby

Mesoscale Discussions in Texas, 2012Mesoscale Discussions in Louisiana, 2012Mesoscale Discussions in Mississippi, 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.