Alert archive / Texas / Mesoscale Discussions in 2012

Mesoscale Discussion 121

February 16, 2012Cameron County, Hidalgo County, Willacy County, Texas

The Storm Prediction Center issued this mesoscale discussion at Feb 16, 2012, 11:35 PM CST for Cameron County, Hidalgo County, Willacy County, Texas. It was in force for 85 min.

The area

The outline as issued.

The facts

Issued
Feb 16, 2012, 11:35 PM CST (05:35 UTC)
Expired
Feb 17, 2012, 1:00 AM CST
In force
85 min
Issued by
the Storm Prediction Center

Counties Cameron County, TX, Hidalgo County, TX, Willacy County, TX

The radar

The Brownsville radar (KBRO), 37 km from the middle of the area, began a volume at 05:38 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

Brownsville Intl, TX (KBRO), launched 00:00Z, 5.6 hours before the alert went out and 40 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, Brownsville Intl, TX at 00:00Z on 2012-02-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 23 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, Brownsville Intl, TX at 00:00Z on 2012-02-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 29 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
23 J/kg
Mixed-layer CIN
-197 J/kg
Mixed-layer LCL
808 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
29 m²/s²
0-3 km storm-relative helicity
43 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

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

009 
ACUS11 KWNS 170535
SWOMCD
SPC MCD 170535 
TXZ000-170700-

MESOSCALE DISCUSSION 0121
NWS STORM PREDICTION CENTER NORMAN OK
1135 PM CST THU FEB 16 2012

AREAS AFFECTED...DEEP S TX

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 170535Z - 170700Z

AN ISOLATED HAIL THREAT /DIAMETERS APPROACHING OR LOCALLY EXCEEDING
1 INCH/ ARE POSSIBLE OVER DEEP SOUTH TX /SERN HIDALGO...CAMERON AND
WILLACY COUNTIES/ BETWEEN 06-08Z.  A SPATIOTEMPORAL LIMIT AND A LOW
PROBABILITY FOR SEVERE STORMS PRECLUDE THE NEED FOR A WATCH.

ALTHOUGH DIABATIC COOLING HAS SUPPORTED AN INCREASE IN SURFACE BASED
INHIBITION OVER DEEP S TX...SUSTAINED ELEVATED STORMS TRACKING NEWD
FROM NERN MEXICO ARE LIKELY BEING FED BY GREATER INSTABILITY
RESIDING S OF THE U.S./MEXICO BORDER.  MUCAPE 500-1000 J/KG AND
EFFECTIVE BULK SHEAR OF 40-50 KT ARE SUFFICIENT FOR CONTINUED
SUSTAINED/ORGANIZED UPDRAFTS AS ACTIVITY TRACKS NEWD INTO THE U.S.
SIDE OF THE BORDER INCLUDING BRO.

..PETERS.. 02/17/2012

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

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

LAT...LON   26119858 26549812 26739696 25959674 25689699 25859764
            25959811 26119858

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.