Alert archive / Texas / Mesoscale Discussions in 2015

Mesoscale Discussion 1906

October 31, 2015Brazoria County, Chambers County, Texas

The Storm Prediction Center issued this mesoscale discussion at Oct 31, 2015, 4:46 AM CDT for Brazoria County, Chambers County, Texas. It was in force for 119 min.

The area

The outline as issued.

The facts

Issued: Oct 31, 2015, 4:46 AM CDT (09:46 UTC)
Expired: Oct 31, 2015, 6:45 AM CDT
In force: 119 min
Issued by: the Storm Prediction Center

Counties Brazoria County, TX, Chambers County, TX

The radar

The Houston radar (KHGX), 17 km from the middle of the area, began a volume at 09:47 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, 9.8 hours before the alert went out and 180 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 3 J/kg
Mixed-layer CIN: -93 J/kg
Mixed-layer LCL: 899 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: 326 m²/s²
0-3 km storm-relative helicity: 483 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.5

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.

Issued	Product	Office	Counties	Lasted
Oct 30, 8:22 PM CDT	Mesoscale Discussion	SPC	Bandera, Dimmit, Edwards, Gillespie, Kerr, Kimble and 12 more	113 min
Oct 30, 11:15 PM CDT	Mesoscale Discussion	SPC	Bandera, Blanco, Edwards, Gillespie, Kendall, Kerr and 7 more	2 hr
Oct 31, 1:17 AM CDT	Mesoscale Discussion	SPC	Bastrop, Bexar, Blanco, Burnet, Caldwell, Comal and 6 more	58 min
Oct 31, 1:51 AM CDT	Mesoscale Discussion	SPC	Austin, Brazoria, Chambers, Colorado, Fort Bend, Harris and 3 more	114 min
Oct 31, 2:57 AM CDT	Tornado Watch	SPC	Brazoria, Chambers, Fort Bend, Galveston, Hardin, Harris and 5 more	9 hr
Oct 31, 6:54 AM CDT	Tornado Watch	SPC	Jasper, Newton	5 hr
Oct 31, 7:35 AM CDT	Mesoscale Discussion	SPC	Chambers, Jefferson	85 min
Oct 31, 10:03 AM CDT	Mesoscale Discussion	SPC	Brazoria, Chambers, Fort Bend, Galveston, Hardin, Harris and 6 more	57 min

Nearby

Mesoscale Discussions in Texas, 2015 Every mesoscale discussion in 2015

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.