Alert archive / Texas / Mesoscale Discussions in 2019

Mesoscale Discussion 2113

October 24, 20194 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Oct 24, 2019, 9:42 PM CDT for 4 counties in Texas. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued
Oct 24, 2019, 9:42 PM CDT (02:42 UTC)
Expired
Oct 24, 2019, 11:15 PM CDT
In force
93 min
Issued by
the Storm Prediction Center
Chance of a watch
5%

Counties La Salle County, TX, Live Oak County, TX, McMullen County, TX, Webb County, TX

The radar

The Corpus Christi radar (KCRP), 145 km from the middle of the area, began a volume at 02:42 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 00:00Z, 2.7 hours before the alert went out and 162 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 2019-10-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1070 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 2019-10-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 37 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
1070 J/kg
Mixed-layer CIN
-19 J/kg
Mixed-layer LCL
732 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
37 m²/s²
0-3 km storm-relative helicity
61 m²/s²
Significant tornado parameter
0.2
Supercell composite
3.0

Open this sounding in Storm Lab

The text

As transmitted.

767 
ACUS11 KWNS 250242
SWOMCD
SPC MCD 250242 
TXZ000-250415-

Mesoscale Discussion 2113
NWS Storm Prediction Center Norman OK
0942 PM CDT Thu Oct 24 2019

Areas affected...portions of southern Texas

Concerning...Severe potential...Watch unlikely 

Valid 250242Z - 250415Z

Probability of Watch Issuance...5 percent

SUMMARY...A localized damaging wind/brief tornado threat will exist
for the next 1 to 2 hours, mainly across LaSalle and McMullen
counties.

DISCUSSION...A bowing segment has formed in western La Salle county
with some hint of a weak rear inflow jet. Temperatures in the low
80s with dewpoints in the low 70s ahead of this line are yielding
MLCAPE around 1000 J/kg per RAP mesoanalysis. This will be
sufficient for a continued severe threat for 1 to 2 more hours as
this portion of the line continues to move east. In addition, backed
surface flow has yielded 0-1 SRH around 150 m2/s2. 850 mb flow is
quite weak (<10 knots) which will likely limit a greater tornado
threat, but the low-level turning may be sufficient for a brief QLCS
tornado on the leading edge of this bowing segment.

..Bentley/Hart.. 10/25/2019

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

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

LAT...LON   28729941 28829888 28759809 28449778 28019784 27779836
            27719907 27779944 27879979 28419956 28729941

Nearby

Mesoscale Discussions in Texas, 2019Every mesoscale discussion in 2019

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.