Alert archive / Texas / Mesoscale Discussions in 2017

Mesoscale Discussion 948

June 4, 201711 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Jun 4, 2017, 5:14 PM CDT for 11 counties in Texas. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Jun 4, 2017, 5:14 PM CDT (22:14 UTC)
Expired
Jun 4, 2017, 7:15 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
Chance of a watch
5%

Counties Aransas County, TX, Brooks County, TX, Cameron County, TX, Duval County, TX, Hidalgo County, TX, Jim Wells County, TX, Kenedy County, TX, Kleberg County, TX, Nueces County, TX, San Patricio County, TX, Willacy County, TX

The radar

The Corpus Christi radar (KCRP), 78 km from the middle of the area, began a volume at 22:16 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, 10.2 hours before the alert went out and 78 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 2017-06-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1740 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 2017-06-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 14 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
1740 J/kg
Mixed-layer CIN
-64 J/kg
Mixed-layer LCL
863 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
14 m²/s²
0-3 km storm-relative helicity
42 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

360 
ACUS11 KWNS 042214
SWOMCD
SPC MCD 042214 
TXZ000-050015-

Mesoscale Discussion 0948
NWS Storm Prediction Center Norman OK
0514 PM CDT Sun Jun 04 2017

Areas affected...Portions of south Texas

Concerning...Severe potential...Watch unlikely 

Valid 042214Z - 050015Z

Probability of Watch Issuance...5 percent

SUMMARY...Isolated strong/severe storms will be possible through
early evening with a risk for damaging winds and perhaps hail.  A
watch is not anticipated due to the localized nature of the threat.

DISCUSSION...Thunderstorms were noted in regional radar composite
imagery over south Texas this afternoon in the vicinity of a sea
breeze boundary, likely augmented by weak ascent with a subtle
mid-level impulse. A severe thunderstorm over southern Kennedy
county was propagating south near the sea breeze boundary.
Temperatures in the 90s and dew points mostly in the 70s have
yielded moderate surface-based buoyancy.  Light southeast/south
low-level flow beneath weak westerlies aloft have resulted in 35-40
kts of westerly effective bulk shear.  The more intense storms will
pose a risk for damaging winds as water loading within a high PW
environment drives strong downdrafts.  Additional storm development
is expected along the sea breeze and resulting from outflow boundary
interactions.

..Bunting/Thompson.. 06/04/2017

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...CRP...BRO...

LAT...LON   26789741 26299725 25979727 25909742 26069767 26129807
            26299835 26809865 27339866 27799853 28169833 28309786
            28349730 28269693 27969696 27509726 27269734 26789741

Nearby

Mesoscale Discussions in Texas, 2017Every mesoscale discussion in 2017

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.