Alert archive / Texas / Mesoscale Discussions in 2013

Mesoscale Discussion 2

January 8, 2013Chambers County, Galveston County, Texas

The Storm Prediction Center issued this mesoscale discussion at Jan 8, 2013, 7:02 AM CST for Chambers County, Galveston County, Texas. It was in force for 88 min.

The area

The outline as issued.

The facts

Issued
Jan 8, 2013, 7:02 AM CST (13:02 UTC)
Expired
Jan 8, 2013, 8:30 AM CST
In force
88 min
Issued by
the Storm Prediction Center
Chance of a watch
5%

Counties Chambers County, TX, Galveston County, TX

The radar

The Houston radar (KHGX), 40 km from the middle of the area, began a volume at 13:03 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

Lake Charles Mun, LA (KLCH), launched 12:00Z, 1.0 hours before the alert went out and 204 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, Lake Charles Mun, LA at 12:00Z on 2013-01-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Lake Charles Mun, LA at 12:00Z on 2013-01-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 258 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
528 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
258 m²/s²
0-3 km storm-relative helicity
289 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

640 
ACUS11 KWNS 081302
SWOMCD
SPC MCD 081302 
TXZ000-081430-

MESOSCALE DISCUSSION 0002
NWS STORM PREDICTION CENTER NORMAN OK
0702 AM CST TUE JAN 08 2013

AREAS AFFECTED...UPPER TX COAST

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 081302Z - 081430Z

PROBABILITY OF WATCH ISSUANCE...5 PERCENT

SUMMARY...A NEAR-SHORE SEVERE/WATERSPOUT POTENTIAL COULD OCCUR ALONG
THE UPPER TX COAST THIS MORNING...ALTHOUGH ANY SUCH POTENTIAL SHOULD
REMAIN VERY ISOLATED /AND OF SHORT DURATION/ THIS MORNING. NO WATCH
IS ANTICIPATED.

DISCUSSION...RECENT RADAR IMAGERY /SINCE 1230Z/ IS INDICATIVE OF A
STORM WITH UPDRAFT ROTATION JUST OFF THE UPPER TX COAST...SOUTHWEST
OF THE FREEPORT TX VICINITY AS OF 1250Z. THIS TSTM IS LIKELY
OCCURRING VERY NEAR/PERHAPS JUST A BIT NORTH OF A SHARPENING WARM
FRONT THAT DEMARCATES RELATIVELY COOL CONTINENTAL TRAJECTORIES
INLAND AND A MORE MOISTURE-RICH AIR MASS /60S F SURFACE DEWPOINTS/
OVER THE WESTERN GULF OF MEXICO. WHILE LOW-LEVEL/DEEP LAYER SHEAR IS
MORE THAN ADEQUATE FOR SUPERCELLS PER A LONG-CURVING HODOGRAPH PER
THE HOUSTON WSR-88D VWP...THIS STORM SHOULD TEND TO REMAIN OFFSHORE
FAVORING THE NEARLY-STALLED SURFACE BOUNDARY AND/OR BECOME
INCREASINGLY ELEVATED TOWARD THE COAST. WHILE A NEAR-SHORE SEVERE
POTENTIAL CANNOT BE RULED OUT INCLUDING THE POSSIBILITY OF
WATERSPOUTS...IT SHOULD REMAIN MARGINAL/ISOLATED.

..GUYER/CORFIDI.. 01/08/2013

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

ATTN...WFO...LCH...HGX...

LAT...LON   28429543 28919559 29319523 29739486 29779414 29309408
            28429543

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jan 8, 3:53 PM CSTMesoscale DiscussionSPCAtascosa, Bandera, Dimmit, Frio, Gillespie, Jim Hogg and 13 more3 hr

Nearby

Mesoscale Discussions in Texas, 2013Every mesoscale discussion in 2013

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.