Mesoscale Discussion 937

Issued

Jun 12, 2021, 2:09 PM MDT (20:09 UTC)

Expired

Jun 12, 2021, 4:15 PM MDT

In force

2 hr

Issued by

the Storm Prediction Center

Concerning

Severe potential...severe thunderstorm watch likely

Chance of a watch

80%

Counties Chaves County, NM, Colfax County, NM, Curry County, NM, De Baca County, NM, Guadalupe County, NM, Harding County, NM, Lincoln County, NM, Mora County, NM, Quay County, NM, Roosevelt County, NM, San Miguel County, NM, Union County, NM, Bailey County, TX, Cochran County, TX, Deaf Smith County, TX, Hartley County, TX, Oldham County, TX, Parmer County, TX

The Cannon AFB radar (KFDX), 62 km from the middle of the area, began a volume at 20:10 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.

• Severe Thunderstorm Watch 262Jun 12, 2:45 PM MDT

035 
ACUS11 KWNS 122009
SWOMCD
SPC MCD 122009 
TXZ000-NMZ000-COZ000-122215-

Mesoscale Discussion 0937
NWS Storm Prediction Center Norman OK
0309 PM CDT Sat Jun 12 2021

Areas affected...a large part of eastern NM...far southeast CO...TX
Panhandle and South Plains

Concerning...Severe potential...Severe Thunderstorm Watch likely 

Valid 122009Z - 122215Z

Probability of Watch Issuance...80 percent

SUMMARY...Isolated to widely scattered thunderstorms are forecast to
develop near I-25 along the CO/NM border southward to the Sacramento
range this afternoon.  Large to very large hail, severe gusts 60-85
mph, and a tornado are possible mainly across parts of eastern NM
late this afternoon/evening and eventually moving into the TX
Panhandle and TX South Plains later this evening into the overnight.

DISCUSSION...Visible-satellite imagery shows towering cumulus over
the Sangre de Cristos near the I-25 CO/NM border and also farther
south over the Sacramento mountains.  Strong heating via clear to
mostly clear skies has resulted in temperatures warming into the 80s
deg F over the northeast quadrant of NM and lower 90s in southeast
NM.  Record-breaking buoyancy (4100 J/kg MLCAPE), sampled by the 12
UTC Amarillo raob, resides over eastern NM and the TX Panhandle this
afternoon.  The RAP 1-hr forecast sounding for Tucumcari, NM from
the 18 UTC model run valid at 19 UTC, showed a surface
temperature/dewpoint of 74/69 deg F beneath a 9 deg C/km 700-500 mb
lapse rate.  The cool bias in the surface temperature was noted
compared to the 19 UTC observation of 81 deg F.  Modifying the
forecast sounding for surface conditions yielded 4500 J/kg MLCAPE
and a capping inversion was noted at 700 mb.  The strongly veering
flow with 10 kt easterlies at the surface veering and strengthening
to 25 kt at 6 km AGL, yields around 35-kt effective shear.

Expecting storms to initially pose an isolated hail/wind risk with
storm coverage remaining isolated given the overall weak forcing
setup.  However, as storms move east away from the terrain,
increasing low-level moisture/buoyancy may lead to a few more storms
developing during the evening.  The tornado/hail risk will likely
concentrate during the late afternoon/early evening before
transitioning to mostly a severe-wind risk by late evening.

..Smith/Grams.. 06/12/2021

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

ATTN...WFO...LUB...AMA...MAF...PUB...ABQ...EPZ...

LAT...LON   33010548 34130570 35700570 37190520 37230393 36390295
            35250220 33800245 33160311 33010548

Mesoscale Discussions in New Mexico, 2021Mesoscale Discussions in Texas, 2021Every mesoscale discussion in 2021

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.