Alert archive / Texas / Mesoscale Discussions in 2015

Mesoscale Discussion 1871

October 21, 2015Lea County, Roosevelt County, New Mexico; 13 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Oct 21, 2015, 7:48 PM MDT for Lea County, Roosevelt County, New Mexico; 13 counties in Texas. It was in force for 87 min.

The area

The outline as issued.

The facts

Issued: Oct 21, 2015, 7:48 PM MDT (01:48 UTC)
Expired: Oct 21, 2015, 9:15 PM MDT
In force: 87 min
Issued by: the Storm Prediction Center

Counties Lea County, NM, Roosevelt County, NM, Andrews County, TX, Cochran County, TX, Dawson County, TX, Ector County, TX, Gaines County, TX, Loving County, TX, Martin County, TX, Midland County, TX, Reeves County, TX, Terry County, TX, Ward County, TX, Winkler County, TX, Yoakum County, TX

The radar

The Midland/Odessa radar (KMAF), 131 km from the middle of the area, began a volume at 01:51 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

Midland Regional, TX (KMAF), launched 00:00Z, 1.8 hours before the alert went out and 130 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: 1086 J/kg
Mixed-layer CIN: -6 J/kg
Mixed-layer LCL: 738 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 118 m²/s²
0-3 km storm-relative helicity: 156 m²/s²
Significant tornado parameter: 0.5
Supercell composite: 3.5

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 21, 10:31 PM MDT	Mesoscale Discussion	SPC	Andrews, Borden, Crane, Dawson, Ector, Gaines and 11 more	59 min
Oct 22, 12:06 AM MDT	Tornado Watch	SPC	Andrews, Borden, Brewster, Briscoe, Childress, Coke and 32 more	8 hr
Oct 22, 2:51 AM MDT	Mesoscale Discussion	SPC	Baylor, Childress, Coke, Collingsworth, Cottle, Crockett and 22 more	99 min
Oct 22, 12:56 PM MDT	Mesoscale Discussion	SPC	Brewster, Callahan, Coke, Coleman, Concho, Crockett and 15 more	2 hr
Oct 22, 4:47 PM MDT	Mesoscale Discussion	SPC	Concho, Crockett, Edwards, Kimble, Menard, Schleicher and 3 more	58 min
Oct 22, 5:02 PM MDT	Severe Thunderstorm Watch	SPC	Concho, Crockett, Edwards, Irion, Kimble, Menard and 4 more	3 hr

Nearby

Mesoscale Discussions in Texas, 2015 Mesoscale Discussions in New Mexico, 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.