Alert archive / Texas / Mesoscale Discussions in 2018

Mesoscale Discussion 1337

August 21, 20184 states

The Storm Prediction Center issued this mesoscale discussion at Aug 21, 2018, 2:57 PM MDT for 4 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Aug 21, 2018, 2:57 PM MDT (20:57 UTC)
Expired
Aug 21, 2018, 5:00 PM MDT
In force
2 hr
Issued by
the Storm Prediction Center
Chance of a watch
20%

Counties Baca County, CO, Las Animas County, CO, Colfax County, NM, Union County, NM, Cimarron County, OK, Dallam County, TX, Hartley County, TX, Sherman County, TX

The radar

The Pueblo radar (KPUX), 211 km from the middle of the area, began a volume at 21:01 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

Amarillo Airport, TX (KAMA), launched 12:00Z, 9.0 hours before the alert went out and 220 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, Amarillo Airport, TX at 12:00Z on 2018-08-21Temperature 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, Amarillo Airport, TX at 12:00Z on 2018-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 174 square meters per square second.1939Sfc1 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
1514 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
174 m²/s²
0-3 km storm-relative helicity
233 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 21, 11:20 AM MDTMesoscale DiscussionSPCMesa115 min

Nearby

Mesoscale Discussions in Texas, 2018Mesoscale Discussions in Colorado, 2018Mesoscale Discussions in New Mexico, 2018Every mesoscale discussion in 2018

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.