Alert archive / Texas / Mesoscale Discussions in 2007

Mesoscale Discussion 643

May 2, 200713 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 2, 2007, 7:40 AM CDT for 13 counties in Texas. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: May 2, 2007, 7:40 AM CDT (12:40 UTC)
Expired: May 2, 2007, 9:45 AM CDT
In force: 2 hr
Issued by: the Storm Prediction Center

Counties Crane County, TX, Crockett County, TX, Ector County, TX, Loving County, TX, Midland County, TX, Pecos County, TX, Reagan County, TX, Reeves County, TX, Terrell County, TX, Upton County, TX, Val Verde County, TX, Ward County, TX, Winkler County, TX

The radar

The Midland/Odessa radar (KMAF), 84 km from the middle of the area, began a volume at 12:40 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.

Severe Thunderstorm Watch 208May 2, 8:00 AM CDT

The nearest sounding before it

Midland Regional, TX (KMAF), launched 12:00Z, 0.7 hours before the alert went out and 85 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: 948 J/kg
Mixed-layer CIN: -48 J/kg
Mixed-layer LCL: 909 m above ground
0-6 km bulk shear: 47 kt
0-1 km storm-relative helicity: 13 m²/s²
0-3 km storm-relative helicity: 162 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

000 
ACUS11 KWNS 021241
SWOMCD
SPC MCD 021240 
TXZ000-NMZ000-021445-

MESOSCALE DISCUSSION 0643
NWS STORM PREDICTION CENTER NORMAN OK
0740 AM CDT WED MAY 02 2007

AREAS AFFECTED...PORTIONS SW/W-CENTRAL TX...SMALL PART OF EXTREME
SERN NM.

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 021240Z - 021445Z

SVR TSTM POTENTIAL FCST TO INCREASE THROUGH MIDDAY ACROSS THIS
REGION...AS SFC DIABATIC HEATING NEAR AND S OF WARM FRONT
DIABATICALLY HEATS/DESTABILIZES AIR MASS IN ENVIRONMENT OF FAVORABLE
VERTICAL SHEAR. 

AT 12Z...SFC ANALYSIS INDICATED LOW BETWEEN FST-GDP...WITH WARM
FRONT ESEWD BETWEEN FST-INK TO VICINITY UVA AND SAT.  THIS FRONT IS
EXPECTED TO DRIFT/MIX NWD ACROSS I-10 DURING NEXT SEVERAL HOURS. 
MEANWHILE...SFC HEATING SHOULD ERODE WEAK CAP EVIDENT IN MAF RAOB
FROM WNW-ESE...WITH STRONGER CINH EVIDENT AROUND DRT.  EVEN THOUGH N
OF WARM FRONT...SHALLOW CHARACTER OF STABLE LAYER IN MAF RAOB
INDICATES SOME POTENTIAL FOR STG-SVR GUSTS GENERATED ALONG SRN EDGE
OF EXISTING COMPLEX TO REACH SFC.  ADDITIONAL DEVELOPMENT MAY OCCUR
SWD TOWARD WARM FRONTAL ZONE AND INTO WARM SECTOR THROUGH FORENOON
HOURS.  RICH LOW LEVEL MOISTURE WITH TEMPS HEATING INTO 70S F WILL
CONTRIBUTE TO MLCAPES 1500-2000 J/KG DEVELOPING BY 15Z...AND
INCREASING TO 2000-3000 J/KG BY 17Z ALONG AND S OF WARM FRONT OVER
SW TX.  ALTHOUGH SFC WINDS MAY REMAIN WEAK...EFFECTIVE BULK SHEAR OF
35 KT NEAR INK -- INCREASING SWD TO AROUND 50 KT NEAR RIO
GRANDE...WILL SUPPORT SUPERCELL AND BOW ECHO POTENTIAL.

REF SPC MESOSCALE DISCUSSION 642 FOR HEAVY RAIN THREAT OVER NRN PART
OF THIS AREA.

..EDWARDS.. 05/02/2007

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

ATTN...WFO...EWX...SJT...MAF...

30540314 31320380 31730378 31890363 32100325 32130278
32130208 31840156 31460126 31010079 30520052 29980054
29440096

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 1, 7:08 PM CDT	Mesoscale Discussion	SPC	Austin, Bandera, Bastrop, Bexar, Blanco, Brazos and 29 more	97 min
May 2, 7:19 AM CDT	Mesoscale Discussion	SPC	Andrews, Dawson, Ector, Gaines, Loving, Martin and 4 more	2 hr
May 2, 8:02 AM CDT	Severe Thunderstorm Watch	SPC	Andrews, Borden, Coke, Crane, Crockett, Dawson and 20 more	6 hr
May 2, 10:11 AM CDT	Mesoscale Discussion	SPC	Brewster, Crane, Crockett, Glasscock, Howard, Irion and 7 more	94 min
May 2, 12:07 PM CDT	Mesoscale Discussion	SPC	Culberson, Hudspeth, Jeff Davis, Loving, Reeves	113 min
May 2, 12:39 PM CDT	Mesoscale Discussion	SPC	Bandera, Brown, Callahan, Coke, Coleman, Comanche and 29 more	66 min
May 2, 12:50 PM CDT	Tornado Watch	SPC	Bandera, Brown, Burnet, Callahan, Coke, Coleman and 31 more	6 hr
May 2, 1:53 PM CDT	Severe Thunderstorm Watch	SPC	Andrews, Crane, Culberson, Dawson, Ector, Gaines and 14 more	7 hr
May 2, 2:38 PM CDT	Mesoscale Discussion	SPC	Bosque, Coryell, Dallas, Denton, Ellis, Erath and 16 more	2 hr
May 2, 3:08 PM CDT	Mesoscale Discussion	SPC	Dimmit, Frio, Kinney, Maverick, Uvalde, Val Verde and 1 more	97 min
May 2, 3:43 PM CDT	Tornado Watch	SPC	Anderson, Bell, Bosque, Collin, Comanche, Cooke and 33 more	6 hr
May 2, 5:08 PM CDT	Mesoscale Discussion	SPC	Atascosa, Bandera, Bastrop, Bexar, Blanco, Burleson and 20 more	67 min
May 2, 5:53 PM CDT	Tornado Watch	SPC	Atascosa, Bandera, Bastrop, Bexar, Blanco, Burnet and 27 more	7 hr
May 2, 6:05 PM CDT	Mesoscale Discussion	SPC	Andrews, Brewster, Cochran, Coke, Crane, Culberson and 22 more	85 min
May 2, 6:52 PM CDT	Tornado Watch	SPC	Brewster, Crockett, Jeff Davis, Pecos, Presidio, Terrell	3 hr
May 2, 6:54 PM CDT	Mesoscale Discussion	SPC	Anderson, Bell, Bosque, Brazos, Burnet, Camp and 54 more	81 min

Nearby

Mesoscale Discussions in Texas, 2007 Every 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; radar from the NEXRAD Level II archive.