Alert archive / Texas / Mesoscale Discussions in 2016

Mesoscale Discussion 376

April 12, 201613 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 12, 2016, 11:06 PM CDT for 13 counties in Texas. It was in force for 114 min.

The area

The outline as issued.

The facts

Issued
Apr 12, 2016, 11:06 PM CDT (04:06 UTC)
Expired
Apr 13, 2016, 1:00 AM CDT
In force
114 min
Issued by
the Storm Prediction Center
Chance of a watch
80%

Counties Austin County, TX, Brazoria County, TX, Colorado County, TX, DeWitt County, TX, Fayette County, TX, Fort Bend County, TX, Harris County, TX, Jackson County, TX, Lavaca County, TX, Matagorda County, TX, Victoria County, TX, Waller County, TX, Wharton County, TX

The radar

The Houston radar (KHGX), 121 km from the middle of the area, began a volume at 04:06 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

Corpus Christi, TX (KCRP), launched 00:00Z, 4.1 hours before the alert went out and 208 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 00:00Z on 2016-04-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 634 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 00:00Z on 2016-04-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 34 square meters per square second.1939587897Sfc1 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
634 J/kg
Mixed-layer CIN
-170 J/kg
Mixed-layer LCL
912 m above ground
0-6 km bulk shear
64 kt
0-1 km storm-relative helicity
34 m²/s²
0-3 km storm-relative helicity
247 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.6

Open this sounding in Storm Lab

The text

As transmitted.

018 
ACUS11 KWNS 130406
SWOMCD
SPC MCD 130406 
TXZ000-130600-

MESOSCALE DISCUSSION 0376
NWS STORM PREDICTION CENTER NORMAN OK
1106 PM CDT TUE APR 12 2016

AREAS AFFECTED...SCNTRL AND SE TX

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 

VALID 130406Z - 130600Z

PROBABILITY OF WATCH ISSUANCE...80 PERCENT

SUMMARY...A SEVERE THREAT IS LIKELY TO CONTINUE...MOVING EWD FROM
SCNTRL TX INTO SE TX OVER THE NEXT FEW HOURS. WIND DAMAGE AND HAIL
WILL BE THE PRIMARY THREATS. WW ISSUANCE WILL LIKELY BE NEEDED
WITHIN THE HOUR.

DISCUSSION...LATEST SFC ANALYSIS SHOWS A QUASI-STATIONARY FRONT
LOCATED FROM SCNTRL TX EXTENDING ENEWD ACROSS SE TX. A
MULTI-SEGMENTED LINE WITH A BOWING STRUCTURE AND EMBEDDED SUPERCELL
IS LOCATED TO THE ENE OF SAN ANTONIO. THIS LINE WILL CONTINUE TO
MOVE EWD INTO SE TX OVER THE NEXT FEW HOURS...REMAINING PARALLEL TO
THE FRONT NEAR AND ON THE COOL SIDE OF THE BOUNDARY. ALTHOUGH
INSTABILITY IS WEAK IN THE HOUSTON AREA...THE LATEST HGX WSR-88D VWP
SHOWS 65 TO 70 KT OF 0-6 KM SHEAR WITH SUBSTANTIAL DIRECTIONAL SHEAR
FROM 0 TO 3 KM AGL. THIS WIND PROFILE WILL BE FAVORABLE FOR BOWING
LINE SEGMENTS WITH WIND DAMAGE AND POSSIBLY SUPERCELL STRUCTURES.
THE STRONG DEEP-LAYER SHEAR COMBINED WITH MODESTLY STEEP LAPSE RATES
MAY ALSO BE ENOUGH FOR HAIL WITH THE MORE INTENSE CORES.

..BROYLES/THOMPSON.. 04/13/2016

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

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

LAT...LON   28739577 28589733 29079751 29699735 30119672 30319542
            29729468 28739577

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 12, 7:26 PM CDTMesoscale DiscussionSPCAtascosa, Bandera, Bastrop, Bexar, Caldwell, Comal and 17 more3 hr
Apr 12, 7:45 PM CDTSevere Thunderstorm WatchSPCAtascosa, Bandera, Bee, Bexar, Blanco, Caldwell and 26 more5 hr
Apr 12, 9:43 PM CDTMesoscale DiscussionSPCAtascosa, Bandera, Bee, Bexar, Blanco, Caldwell and 25 more92 min
Apr 12, 11:26 PM CDTSevere Thunderstorm WatchSPCAustin, Brazoria, Chambers, Colorado, Fort Bend, Galveston and 5 more6 hr
Apr 13, 2:01 AM CDTMesoscale DiscussionSPCBrazoria, Chambers, Fort Bend, Galveston, Harris, Jackson and 3 more119 min

Nearby

Mesoscale Discussions in Texas, 2016Every mesoscale discussion in 2016

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.