Alert archive / Colorado / Mesoscale Discussions in 2020

Mesoscale Discussion 1237

July 15, 20205 states

The Storm Prediction Center issued this mesoscale discussion at Jul 15, 2020, 5:14 PM MDT for 5 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Jul 15, 2020, 5:14 PM MDT (23:14 UTC)
Expired
Jul 15, 2020, 7:15 PM MDT
In force
2 hr
Issued by
the Storm Prediction Center
Concerning
Severe thunderstorm watch 375
All 44 counties

Baca County, CO, Bent County, CO, Cheyenne County, CO, Crowley County, CO, El Paso County, CO, Elbert County, CO, Kiowa County, CO, Kit Carson County, CO, Las Animas County, CO, Lincoln County, CO, Otero County, CO, Prowers County, CO, Pueblo County, CO, Grant County, KS, Greeley County, KS, Hamilton County, KS, Kearny County, KS, Logan County, KS, Morton County, KS, Stanton County, KS, Stevens County, KS, Wallace County, KS, Wichita County, KS, Colfax County, NM, Guadalupe County, NM, Harding County, NM, Mora County, NM, Quay County, NM, San Miguel County, NM, Union County, NM, Cimarron County, OK, Texas County, OK, Armstrong County, TX, Carson County, TX, Dallam County, TX, Deaf Smith County, TX, Hansford County, TX, Hartley County, TX, Hutchinson County, TX, Moore County, TX, Oldham County, TX, Potter County, TX, Randall County, TX, Sherman County, TX

The radar

The Amarillo radar (KAMA), 207 km from the middle of the area, began a volume at 23:14 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.

The nearest sounding before it

Amarillo Airport, TX (KAMA), launched 12:00Z, 11.2 hours before the alert went out and 208 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 2020-07-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 126 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Amarillo Airport, TX at 12:00Z on 2020-07-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 184 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
126 J/kg
Mixed-layer CIN
-562 J/kg
Mixed-layer LCL
1844 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
184 m²/s²
0-3 km storm-relative helicity
220 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

592 
ACUS11 KWNS 152315
SWOMCD
SPC MCD 152314 
KSZ000-TXZ000-OKZ000-COZ000-NMZ000-160115-

Mesoscale Discussion 1237
NWS Storm Prediction Center Norman OK
0614 PM CDT Wed Jul 15 2020

Areas affected...Eastern CO...Eastern NM

Concerning...Severe Thunderstorm Watch 375...

Valid 152314Z - 160115Z

The severe weather threat for Severe Thunderstorm Watch 375
continues.

SUMMARY...Convection should spread east across the remainder of
ww375 later this evening. Wind/hail remain possible.

DISCUSSION...With the upper ridge remaining centered over TX,
several weak disturbances, likely convectively enhanced, are
rotating across northern Mexico into NM/CO. One such feature may be
enhancing thunderstorm activity across southern CO that is now
shifting east of the higher terrain. Another disturbance may be
located along the AZ/NM border, and this appears partly responsible
for upscale growth over NM. In both cases, boundary-layer heating is
the primary driver, along with orographic forcing. Over the next few
hours, convection should spread across the southwestern High Plains
toward the NM/TX border, extending into southeast CO. This activity
will likely persist well into the late-evening hours as LLJ is
forecast to increase across the TX South Plains after sunset.

Watch may be warranted later this evening downstream from parts of
the TX Panhandle into southwest KS.

..Darrow.. 07/15/2020

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...DDC...GLD...LUB...AMA...PUB...BOU...ABQ...

LAT...LON   34590505 39420477 39310086 34570127 34590505

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 15, 1:40 PM MDTMesoscale DiscussionSPCBaca, Bent, Crowley, Douglas, Elbert, El Paso and 6 more95 min
Jul 15, 2:25 PM MDTSevere Thunderstorm WatchSPCBaca, Bent, Cheyenne, Crowley, Elbert, El Paso and 7 more8 hr
Jul 14, 7:13 PM MDTSevere Thunderstorm WatchSPCBarber, Clark, Comanche, Edwards, Finney, Ford and 15 more7 hr
Jul 14, 8:24 PM MDTMesoscale DiscussionSPCFinney, Grant, Gray, Hamilton, Haskell, Kearny and 5 more2 hr
Jul 14, 10:21 PM MDTMesoscale DiscussionSPCBarber, Clark, Comanche, Edwards, Ford, Gray and 11 more114 min
Jul 15, 12:07 AM MDTMesoscale DiscussionSPCButler, Chase, Geary, Greenwood, Harvey, Kingman and 6 more53 min
Jul 15, 12:25 AM MDTSevere Thunderstorm WatchSPCChase, Dickinson, Harvey, Lyon, McPherson, Marion and 4 more3 hr

Nearby

Mesoscale Discussions in Colorado, 2020Mesoscale Discussions in Texas, 2020Mesoscale Discussions in Kansas, 2020Every mesoscale discussion in 2020

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.