Alert archive / Texas / Mesoscale Discussions in 2012

Mesoscale Discussion 809

May 14, 201215 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 14, 2012, 1:55 PM CDT for 15 counties in Texas. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
May 14, 2012, 1:55 PM CDT (18:55 UTC)
Expired
May 14, 2012, 4:30 PM CDT
In force
3 hr
Issued by
the Storm Prediction Center
Chance of a watch
40%

Counties Brewster County, TX, Concho County, TX, Crockett County, TX, Edwards County, TX, Irion County, TX, Jeff Davis County, TX, Menard County, TX, Pecos County, TX, Presidio County, TX, Reagan County, TX, Schleicher County, TX, Sutton County, TX, Terrell County, TX, Tom Green County, TX, Val Verde County, TX

The radar

The Midland/Odessa radar (KMAF), 190 km from the middle of the area, began a volume at 18:58 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

Midland Regional, TX (KMAF), launched 12:00Z, 6.9 hours before the alert went out and 190 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, Midland Regional, TX at 12:00Z on 2012-05-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 40 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, Midland Regional, TX at 12:00Z on 2012-05-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 3 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
40 J/kg
Mixed-layer CIN
-330 J/kg
Mixed-layer LCL
1130 m above ground
0-6 km bulk shear
56 kt
0-1 km storm-relative helicity
3 m²/s²
0-3 km storm-relative helicity
-5 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.

242 
ACUS11 KWNS 141856
SWOMCD
SPC MCD 141855
TXZ000-142130-

MESOSCALE DISCUSSION 0809
NWS STORM PREDICTION CENTER NORMAN OK
0155 PM CDT MON MAY 14 2012

AREAS AFFECTED...SWRN TX

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 141855Z - 142130Z

PROBABILITY OF WATCH ISSUANCE...40 PERCENT

SUMMARY...STORMS ARE EXPECTED TO INTENSIFY LATER THIS
AFTERNOON...WITH LARGE HAIL AND A FEW STRONG WIND GUSTS LIKELY.

DISCUSSION...VISIBLE IMAGERY SHOWS HEATING OCCURRING AHEAD OF AN
OUTFLOW BOUNDARY N OF THE BIG BEND AREA. STORMS DO NOT APPEAR SEVERE
AT THIS TIME...BUT POCKETS OF DESTABILIZATION ALONG WITH COOLING
ALOFT WITH THE UPPER VORTICITY CENTER SHOULD ALLOW FOR AN INCREASE
IN COVERAGE...WITH SRN FRINGE OF ONGOING ACTIVITY INTENSIFYING.
40-50 KT DEEP LAYER SHEAR WILL PROVIDE LONG HODOGRAPHS WHICH WILL
FAVOR SUPERCELLS WITH LARGE HAIL. A FEW STORMS MAY BOW WITH A WIND
THREAT.

..JEWELL/HART.. 05/14/2012

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

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

LAT...LON   30240474 30810530 30780364 30920266 31310196 31790153
            31760061 31379972 30549988 29600058 29270109 28940216
            28890299 28990345 29390420 29720460 30240474

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 13, 9:14 PM CDTMesoscale DiscussionSPCCulberson, Jeff Davis, Loving, Reeves, Ward61 min
May 13, 9:21 PM CDTSevere Thunderstorm WatchSPCBrewster, Crane, Culberson, Jeff Davis, Loving, Pecos and 4 more7 hr
May 13, 11:37 PM CDTMesoscale DiscussionSPCCrane, Culberson, Ector, Jeff Davis, Loving, Pecos and 3 more53 min
May 14, 2:17 AM CDTMesoscale DiscussionSPCVal Verde118 min
May 14, 2:55 PM CDTSevere Thunderstorm WatchSPCBrewster, Jeff Davis, Pecos, Presidio, Reeves, Terrell5 hr
May 14, 6:57 PM CDTMesoscale DiscussionSPCMaverick63 min

Nearby

Mesoscale Discussions in Texas, 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.