Alert archive / Texas / Mesoscale Discussions in 2012

Mesoscale Discussion 785

May 11, 20129 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 11, 2012, 2:41 AM CDT for 9 counties in Texas. It was in force for 34 min.

The area

The outline as issued.

The facts

Issued: May 11, 2012, 2:41 AM CDT (07:41 UTC)
Expired: May 11, 2012, 3:15 AM CDT
In force: 34 min
Issued by: the Storm Prediction Center

Counties Cameron County, TX, Chambers County, TX, Galveston County, TX, Hidalgo County, TX, Jefferson County, TX, Kenedy County, TX, Liberty County, TX, Orange County, TX, Willacy County, TX

The radar

The Corpus Christi radar (KCRP), 104 km from the middle of the area, began a volume at 07:43 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

Corpus Christi, TX (KCRP), launched 00:00Z, 7.7 hours before the alert went out and 89 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 2214 J/kg
Mixed-layer CIN: -8 J/kg
Mixed-layer LCL: 636 m above ground
0-6 km bulk shear: 54 kt
0-1 km storm-relative helicity: 204 m²/s²
0-3 km storm-relative helicity: 274 m²/s²
Significant tornado parameter: 3.4
Supercell composite: 14.5

Open this sounding in Storm Lab

The text

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

134 
ACUS11 KWNS 110742
SWOMCD
SPC MCD 110741
LAZ000-TXZ000-110815-

MESOSCALE DISCUSSION 0785
NWS STORM PREDICTION CENTER NORMAN OK
0241 AM CDT FRI MAY 11 2012

AREAS AFFECTED...S TX THROUGH THE UPPER TX COAST

CONCERNING...TORNADO WATCH 273...

VALID 110741Z - 110815Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 273 CONTINUES.

SUMMARY...LOCAL TEMPORAL EXTENSIONS OF WW 273 WILL BE COORDINATED
WITH WFO BRO AND WFO HOU FOR THEIR RESPECTIVE AREAS OF DEEP S TX AND
THE UPPER TX COAST.  A NEW WW MAY BE NEEDED DOWNSTREAM INTO PART OF
WFO LCH COUNTY WARNING AREA.

DISCUSSION...SEVERE WEATHER THREATS ARE EXPECTED TO PERSIST BEYOND
THE SCHEDULED 08Z EXPIRATION TIME OF WW 273...WITH THE ENVIRONMENTS
OVER DEEP S TX AND THE UPPER TX COAST REMAINING CONDUCIVE FOR SEVERE
STORMS.  IN DEEP S TX...A FEW STORMS NORTH OF BRO /IN ADVANCE OF THE
CONVECTIVE BAND IN HIDALGO AND KENEDY COUNTIES/ INDICATED STORM
ROTATION...WHILE FARTHER NE TORNADIC AND DAMAGING WIND THREATS
CONTINUED ACROSS THE UPPER TX COAST.  THIS LATTER THREAT MAY
PROGRESS NEWD ALONG THE COAST INCLUDING WFO LCH COUNTY WARNING AREA
WHICH WOULD REQUIRE A NEW WW.

..PETERS.. 05/11/2012

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

ATTN...WFO...LCH...HGX...CRP...BRO...

LAT...LON   26309873 27419739 28509627 29029527 29699549 30159494
            30389376 29639390 29369459 28809553 28439629 27459730
            27089742 26039714 25849734 26019794 26089831 26309873

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 10, 7:18 PM CDT	Mesoscale Discussion	SPC	Aransas, Atascosa, Austin, Bastrop, Bee, Bexar and 43 more	57 min
May 10, 7:50 PM CDT	Tornado Watch	SPC	Aransas, Atascosa, Austin, Bastrop, Bee, Bell and 48 more	9 hr
May 10, 9:42 PM CDT	Mesoscale Discussion	SPC	Aransas, Atascosa, Austin, Bastrop, Bee, Bell and 36 more	63 min
May 10, 11:36 PM CDT	Mesoscale Discussion	SPC	Aransas, Brooks, Calhoun, Cameron, Hidalgo, Jackson and 13 more	84 min
May 11, 1:40 AM CDT	Mesoscale Discussion	SPC	Aransas, Austin, Bee, Brazoria, Brooks, Calhoun and 25 more	65 min
May 11, 1:22 PM CDT	Mesoscale Discussion	SPC	Anderson, Bosque, Camp, Cherokee, Collin, Cooke and 28 more	53 min
May 11, 2:13 PM CDT	Mesoscale Discussion	SPC	Atascosa, Austin, Bandera, Bastrop, Bell, Bexar and 41 more	2 hr
May 11, 5:18 PM CDT	Mesoscale Discussion	SPC	Anderson, Angelina, Austin, Bastrop, Bell, Blanco and 40 more	87 min
May 11, 5:51 PM CDT	Mesoscale Discussion	SPC	Bee, Brooks, Duval, Goliad, Hidalgo, Jim Hogg and 7 more	84 min

Nearby

Mesoscale Discussions in Texas, 2012 Every 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.