Alert archive / Texas / Mesoscale Discussions in 2009

Mesoscale Discussion 265

March 25, 200915 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Mar 25, 2009, 7:31 PM CDT for 15 counties in Texas. It was in force for 59 min.

The area

The outline as issued.

The facts

Issued
Mar 25, 2009, 7:31 PM CDT (00:31 UTC)
Expired
Mar 25, 2009, 8:30 PM CDT
In force
59 min
Issued by
the Storm Prediction Center

Counties Austin County, TX, Brazos County, TX, Burleson County, TX, Fayette County, TX, Grimes County, TX, Harris County, TX, Houston County, TX, Madison County, TX, Montgomery County, TX, Polk County, TX, San Jacinto County, TX, Trinity County, TX, Walker County, TX, Waller County, TX, Washington County, TX

The radar

The Houston radar (KHGX), 123 km from the middle of the area, began a volume at 00:32 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 00:00Z, 0.5 hours before the alert went out and 244 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 00:00Z on 2009-03-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3131 joules per kilogram.LCLEL10008507005003002001001 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 00:00Z on 2009-03-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 130 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
3131 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
474 m above ground
0-6 km bulk shear
53 kt
0-1 km storm-relative helicity
130 m²/s²
0-3 km storm-relative helicity
153 m²/s²
Significant tornado parameter
2.5
Supercell composite
9.3

Open this sounding in Storm Lab

The text

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

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 25, 7:12 PM CDTTornado WatchSPCAustin, Brazoria, Chambers, Colorado, Fort Bend, Galveston and 9 more6 hr
Mar 26, 9:14 AM CDTMesoscale DiscussionSPCAtascosa, Bandera, Bexar, Blanco, Caldwell, Comal and 16 more31 min
Mar 26, 9:39 AM CDTSevere Thunderstorm WatchSPCAtascosa, Bandera, Bastrop, Bexar, Blanco, Burnet and 25 more5 hr
Mar 26, 12:43 PM CDTMesoscale DiscussionSPCAransas, Atascosa, Bee, Brazoria, Calhoun, DeWitt and 11 more62 min
Mar 26, 12:57 PM CDTSevere Thunderstorm WatchSPCAransas, Bee, Brazoria, Calhoun, Chambers, Duval and 17 more6 hr
Mar 26, 3:06 PM CDTMesoscale DiscussionSPCHardin, Jasper, Jefferson, Newton, Orange, Tyler54 min
Mar 26, 3:51 PM CDTMesoscale DiscussionSPCAransas, Brazoria, Calhoun, Chambers, Fort Bend, Galveston and 8 more54 min
Mar 26, 3:57 PM CDTTornado WatchSPCAngelina, Cherokee, Hardin, Jasper, Jefferson, Nacogdoches and 6 more7 hr
Mar 26, 4:52 PM CDTMesoscale DiscussionSPCArcher, Clay, Comanche, Eastland, Erath, Hamilton and 9 more83 min
Mar 26, 6:32 PM CDTMesoscale DiscussionSPCDallam4 hr
Mar 26, 6:56 PM CDTMesoscale DiscussionSPCAngelina, Cherokee, Hardin, Jasper, Jefferson, Nacogdoches and 6 more94 min

Nearby

Mesoscale Discussions in Texas, 2009Every mesoscale discussion in 2009

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.