Mesoscale Discussion 699

Issued

May 22, 2021, 10:51 AM MDT (16:51 UTC)

Expired

May 22, 2021, 12:45 PM MDT

In force

114 min

Issued by

the Storm Prediction Center

Concerning

Severe potential...watch likely

Chance of a watch

80%

Counties Adams County, CO, Arapahoe County, CO, Crowley County, CO, Denver County, CO, Douglas County, CO, El Paso County, CO, Elbert County, CO, Huerfano County, CO, Las Animas County, CO, Lincoln County, CO, Otero County, CO, Pueblo County, CO, Teller County, CO, Washington County, CO, Colfax County, NM, Mora County, NM, San Miguel County, NM

The Pueblo radar (KPUX), 75 km from the middle of the area, began a volume at 16:51 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.

• Tornado Watch 193May 22, 12:15 PM MDT
• Tornado Watch 194May 22, 12:40 PM MDT

688 
ACUS11 KWNS 221652
SWOMCD
SPC MCD 221651 
COZ000-NMZ000-221845-

Mesoscale Discussion 0699
NWS Storm Prediction Center Norman OK
1151 AM CDT Sat May 22 2021

Areas affected...Parts of central/eastern New Mexico and Colorado

Concerning...Severe potential...Watch likely 

Valid 221651Z - 221845Z

Probability of Watch Issuance...80 percent

SUMMARY...Initiation of scattered thunderstorms is underway, with a
more substantive increase and intensification near and east of the
Sangre de Cristo Mountains into the Front Range vicinity through 1-3
PM MDT.  This will be accompanied by increasing risk for hail, some
of which could become large and potentially damaging.  One or more
severe weather watches will probably be needed.

DISCUSSION...The elongated mid-level cold core of larger-scale
mid/upper troughing, encompassing much of the Pacific Coast states
into Rockies, is still over western portions of the intermountain
region.  Only a very slow eastward progression is forecast, with the
primary short wave impulse rounding the base of the larger-scale
troughing only gradually pivoting across the lower Colorado Valley
through early evening.

However, one or two more subtle perturbations are progressing
through the eastern periphery of larger-scale cyclonic flow, and,
based on latest water vapor imagery, forcing for ascent with one is
beginning to impact the Sangre de Cristo Mountains into Front Range
vicinity.  Thunderstorms have already initiated near and north
through southwest of the Raton Mesa vicinity, and model output
indicates an increase in thunderstorm development is likely through
19-21Z.

This probably will remain largely focused close to the higher
terrain, where moistening on southeasterly near surface flow is
generally ongoing.  With further insolation and steepening of
lower/mid tropospheric lapse rates, it appears that mixed-layer CAPE
will increase in excess of 1000 J/kg, in the presence of
strengthening deep-layer shear (40-80+ kt in the 500-300 mb layer). 
As this occurs, the environment is expected to become increasingly
conducive to supercells capable of producing large, potentially
damaging hail.  There may be some risk for a brief tornado, but
model forecast soundings suggest substantive enlargement of
low-level hodographs may not occur until much later this afternoon
or early evening.

..Kerr/Guyer.. 05/22/2021

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

ATTN...WFO...GLD...PUB...BOU...ABQ...

LAT...LON   37440504 38960522 39830489 39970367 40010298 39720266
            38770322 36090399 35130458 34810542 35400577 37440504

Mesoscale Discussions in Colorado, 2021Mesoscale Discussions in New Mexico, 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.