Alert archive / Texas / Mesoscale Discussions in 2007

Mesoscale Discussion 856

May 22, 200711 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 22, 2007, 12:35 PM CDT for 11 counties in Texas. It was in force for 115 min.

The area

The outline as issued.

The facts

Issued
May 22, 2007, 12:35 PM CDT (17:35 UTC)
Expired
May 22, 2007, 2:30 PM CDT
In force
115 min
Issued by
the Storm Prediction Center

Counties Aransas County, TX, Bee County, TX, Calhoun County, TX, DeWitt County, TX, Goliad County, TX, Gonzales County, TX, Jackson County, TX, Lavaca County, TX, Refugio County, TX, San Patricio County, TX, Victoria County, TX

The radar

The Corpus Christi radar (KCRP), 100 km from the middle of the area, began a volume at 17:33 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 12:00Z, 5.6 hours before the alert went out and 100 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, Corpus Christi, TX at 12:00Z on 2007-05-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1543 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, Corpus Christi, TX at 12:00Z on 2007-05-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 84 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
1543 J/kg
Mixed-layer CIN
-14 J/kg
Mixed-layer LCL
547 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
84 m²/s²
0-3 km storm-relative helicity
234 m²/s²
Significant tornado parameter
0.9
Supercell composite
6.5

Open this sounding in Storm Lab

The text

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

000 
ACUS11 KWNS 221735
SWOMCD
SPC MCD 221735 
TXZ000-221930-

MESOSCALE DISCUSSION 0856
NWS STORM PREDICTION CENTER NORMAN OK
1235 PM CDT TUE MAY 22 2007

AREAS AFFECTED...SCENTRAL TX/MIDDLE TX COASTAL PLAINS

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 221735Z - 221930Z

AN ISOLATED SVR TSTM OR TWO MAY DEVELOP ALONG THE MIDDLE TX COASTAL
PLAINS OF SCENTRAL TX IN THE NEXT 2-3 HOURS. A WW IS NOT EXPECTED
GIVEN THE LACK OF GREATER AREAL COVERAGE/MARGINAL NATURE OF THE SVR
THREAT. 

LATEST VISIBLE SATELLITE IMAGERY SHOWS MODERATE CU DEVELOPING ALONG
BOTH A N-S ORIENTED CONFLUENT AXIS AND AN OUTFLOW BOUNDARY IN MIDDLE
TX COASTAL PLAINS INVOF MATAGORDA BAY. A MODIFIED 12Z CRP SOUNDING
INDICATES LESS THAN 25 J/KG OF MLCINH ACROSS THE AREA WITH AROUND
2000 J/KG OF MLCAPE. RECENT SFC ANALYSIS SHOWS MODERATE CONVERGENCE
ALONG THE OUTFLOW BOUNDARY. GIVEN CONTINUED HEATING AND
DESTABILIZATION...AN  ISOLATED SVR TSTM MAY DEVELOP...ESPECIALLY
INVOF OF THE OUTFLOW BOUNDARY/CONFLUENCE TROUGH INTERSECTION INVOF
MATAGORDA BAY WHERE CONVERGENCE IS MAXIMIZED.  15-20 KTS BACKED
ESELY LOW LEVEL FLOW ALONG AND JUST EAST OF THE OUTFLOW BOUNDARY
WILL AUGMENT WEAKER MID LEVEL FLOW TO SUPPORT SUFFICIENTLY STRONG
VERTICAL SHEAR PROFILES OF 35-40 KTS TO SUPPORT SUPERCELL STORM
STRUCTURE. THUS DESPITE VERY WARM TEMPERATURES...MARGINAL SVR
HAIL/DMGG WINDS GUSTS WILL BE POSSIBLE.

..CROSBIE.. 05/22/2007

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

ATTN...WFO...HGX...CRP...EWX...

27839696 27849742 28269773 28699783 29479758 29669744
29529675 28609600 28279617

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 21, 9:56 PM CDTMesoscale DiscussionSPCDimmit, Edwards, Kinney, Maverick, Real, Uvalde and 2 more64 min

Nearby

Mesoscale Discussions in Texas, 2007Every 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.