Alert archive / Texas / Mesoscale Discussions in 2015

Mesoscale Discussion 1793

September 10, 20154 states

The Storm Prediction Center issued this mesoscale discussion at Sep 10, 2015, 4:06 PM MDT for 4 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Sep 10, 2015, 4:06 PM MDT (22:06 UTC)
Expired: Sep 10, 2015, 6:30 PM MDT
In force: 2 hr
Issued by: the Storm Prediction Center
Chance of a watch: 20%

Counties Baca County, CO, Grant County, KS, Haskell County, KS, Meade County, KS, Morton County, KS, Seward County, KS, Stanton County, KS, Stevens County, KS, Beaver County, OK, Cimarron County, OK, Texas County, OK, Dallam County, TX, Hansford County, TX, Hartley County, TX, Hutchinson County, TX, Moore County, TX, Ochiltree County, TX, Oldham County, TX, Potter County, TX, Sherman County, TX

The radar

The Amarillo radar (KAMA), 143 km from the middle of the area, began a volume at 22:09 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Severe Thunderstorm Watch 509Sep 10, 4:45 PM MDT

The nearest sounding before it

Amarillo Airport, TX (KAMA), launched 12:00Z, 10.1 hours before the alert went out and 143 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: 350 J/kg
Mixed-layer CIN: -209 J/kg
Mixed-layer LCL: 1421 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: -30 m²/s²
0-3 km storm-relative helicity: -7 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.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 9, 11:56 PM MDT	Mesoscale Discussion	SPC	Marshall, Republic, Washington	2 hr
Sep 10, 12:23 PM MDT	Mesoscale Discussion	SPC	Clay, Cloud, Decatur, Dickinson, Ellis, Ellsworth and 20 more	97 min
Sep 10, 1:59 PM MDT	Severe Thunderstorm Watch	SPC	Barton, Chase, Clay, Cloud, Decatur, Dickinson and 26 more	5 hr
Sep 10, 2:58 PM MDT	Mesoscale Discussion	SPC	Allen, Anderson, Bourbon, Cherokee, Crawford, Douglas and 7 more	3 hr
Sep 10, 4:27 PM MDT	Mesoscale Discussion	SPC	Barton, Chase, Clay, Cloud, Decatur, Dickinson and 35 more	93 min
Sep 10, 4:44 PM MDT	Severe Thunderstorm Watch	SPC	Edwards, Ellis, Finney, Ford, Grant, Gray and 17 more	4 hr

Nearby

Mesoscale Discussions in Texas, 2015 Mesoscale Discussions in Kansas, 2015 Mesoscale Discussions in Oklahoma, 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.