Alert archive / Texas / Mesoscale Discussions in 2015

Mesoscale Discussion 2005

December 12, 201544 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Dec 12, 2015, 2:16 PM CST for 44 counties in Texas. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Dec 12, 2015, 2:16 PM CST (20:16 UTC)
Expired
Dec 12, 2015, 4:45 PM CST
In force
2 hr
Issued by
the Storm Prediction Center
Chance of a watch
20%
All 44 counties

Anderson County, TX, Angelina County, TX, Brazoria County, TX, Camp County, TX, Cass County, TX, Chambers County, TX, Cherokee County, TX, Delta County, TX, Fort Bend County, TX, Franklin County, TX, Freestone County, TX, Gregg County, TX, Grimes County, TX, Harris County, TX, Harrison County, TX, Henderson County, TX, Hopkins County, TX, Houston County, TX, Jackson County, TX, Kaufman County, TX, Leon County, TX, Liberty County, TX, Madison County, TX, Marion County, TX, Matagorda County, TX, Montgomery County, TX, Morris County, TX, Nacogdoches County, TX, Panola County, TX, Polk County, TX, Rains County, TX, Red River County, TX, Rusk County, TX, San Jacinto County, TX, Smith County, TX, Titus County, TX, Trinity County, TX, Tyler County, TX, Upshur County, TX, Van Zandt County, TX, Walker County, TX, Waller County, TX, Wharton County, TX, Wood County, TX

The radar

The Houston radar (KHGX), 144 km from the middle of the area, began a volume at 20:18 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

Lake Charles Mun, LA (KLCH), launched 12:00Z, 8.3 hours before the alert went out and 233 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 2015-12-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 351 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 2015-12-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 204 square meters per square second.193958Sfc1 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
351 J/kg
Mixed-layer CIN
-34 J/kg
Mixed-layer LCL
540 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
204 m²/s²
0-3 km storm-relative helicity
295 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.6

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
Dec 12, 3:43 PM CSTMesoscale DiscussionSPCBaylor, Borden, Briscoe, Childress, Coke, Collingsworth and 39 more2 hr
Dec 12, 5:13 PM CSTSevere Thunderstorm WatchSPCArmstrong, Baylor, Borden, Briscoe, Brown, Callahan and 60 more7 hr

Nearby

Mesoscale Discussions in Texas, 2015Every mesoscale discussion in 2015

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.