Alert archive / Texas / Mesoscale Discussions in 2022

Mesoscale Discussion 621

May 2, 20227 counties in Arkansas; 7 counties in Oklahoma; 17 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 2, 2022, 1:20 PM CDT for 7 counties in Arkansas; 7 counties in Oklahoma; 17 counties in Texas. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
May 2, 2022, 1:20 PM CDT (18:20 UTC)
Expired
May 2, 2022, 3:45 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
Concerning
Severe potential...watch possible
Chance of a watch
40%
All 31 counties

Hempstead County, AR, Howard County, AR, Little River County, AR, Miller County, AR, Pike County, AR, Polk County, AR, Sevier County, AR, Atoka County, OK, Bryan County, OK, Choctaw County, OK, Johnston County, OK, Marshall County, OK, McCurtain County, OK, Pushmataha County, OK, Bowie County, TX, Camp County, TX, Cass County, TX, Collin County, TX, Delta County, TX, Fannin County, TX, Franklin County, TX, Grayson County, TX, Hopkins County, TX, Hunt County, TX, Lamar County, TX, Morris County, TX, Rains County, TX, Red River County, TX, Rockwall County, TX, Titus County, TX, Wood County, TX

The radar

The Western Arkansas radar (KSRX), 198 km from the middle of the area, began a volume at 18:22 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

Fort Worth, TX (KFWD), launched 12:00Z, 6.3 hours before the alert went out and 196 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, Fort Worth, TX at 12:00Z on 2022-05-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1120 joules per kilogram.LCLLFCEL10008507005003002001001 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, Fort Worth, TX at 12:00Z on 2022-05-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 160 square meters per square second.193958Sfc1 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
1120 J/kg
Mixed-layer CIN
-37 J/kg
Mixed-layer LCL
670 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
160 m²/s²
0-3 km storm-relative helicity
303 m²/s²
Significant tornado parameter
0.6
Supercell composite
3.7

Open this sounding in Storm Lab

The text

As transmitted.

706 
ACUS11 KWNS 021820
SWOMCD
SPC MCD 021820 
ARZ000-TXZ000-OKZ000-022045-

Mesoscale Discussion 0621
NWS Storm Prediction Center Norman OK
0120 PM CDT Mon May 02 2022

Areas affected...southeast OK...far northeast TX...parts of
southwest MO

Concerning...Severe potential...Watch possible 

Valid 021820Z - 022045Z

Probability of Watch Issuance...40 percent

SUMMARY...The risk for isolated severe storms may increase this
afternoon. Trends will continue to be monitored for possible watch
issuance.

DISCUSSION...In the wake of earlier convective overturning across
the area, visible satellite loops show a gradual transition from
stable billow clouds to shallow horizontal convective rolls,
indicating that the boundary layer is gradually destabilizing to the
south of a northward-lifting warm front. As surface pressure falls
continue over north-central OK, upper 60s/lower 70s dewpoints should
continue spreading northward in conjunction with pockets of diurnal
heating -- supporting 2000-2500 J/kg pre-convective MLCAPE. Regional
VWP data shows strongly veering flow in the 0-3-km layer owing to
continued warm advection along the axis of a 40-45 knot low-level
jet -- which is resulting in 250-350 m2/s2 boundary-layer SRH. 

While the environment will be favorable for discrete supercells
capable of all hazards this afternoon, weak large-scale ascent
characterized by neutral midlevel height tendencies and a lack of
appreciable low-level convergence casts uncertainty on storm
development and maintenance. With that said, high-resolution
guidance continues to depict at least isolated convective
development along antecedent outflow boundaries. Trends will
continue to be monitored for possible watch issuance.

..Weinman/Hart.. 05/02/2022

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

ATTN...WFO...LZK...SHV...TSA...FWD...OUN...

LAT...LON   33039688 33379693 34199686 34449662 34519632 34719575
            34899439 34669374 34119356 33639351 33189371 32639570
            32699649 33039688

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 2, 2:33 PM CDTMesoscale DiscussionSPCCrittenden2 hr
May 2, 5:08 PM CDTMesoscale DiscussionSPCGarland, Logan, Montgomery, Perry, Polk, Saline and 4 more67 min
May 2, 5:27 PM CDTTornado WatchSPCClark, Conway, Crawford, Faulkner, Franklin, Garland and 15 more7 hr
May 1, 10:30 PM CDTMesoscale DiscussionSPCBeaver, Cimarron, Texas2 hr
May 2, 1:30 PM CDTMesoscale DiscussionSPCAlfalfa, Blaine, Caddo, Canadian, Cleveland, Craig and 29 more2 hr
May 2, 2:02 PM CDTTornado WatchSPCAlfalfa, Blaine, Caddo, Canadian, Carter, Cherokee and 45 more8 hr
May 2, 3:32 PM CDTMesoscale DiscussionSPCAlfalfa, Blaine, Garfield, Grant, Kingfisher, Logan and 2 more88 min
May 2, 5:46 PM CDTMesoscale DiscussionSPCCanadian, Grady, Kay, Logan, Noble, Oklahoma and 2 more59 min
May 1, 7:57 PM CDTMesoscale DiscussionSPCCallahan, Coke, Coleman, Eastland, Fisher, Haskell and 10 more93 min
May 1, 8:22 PM CDTSevere Thunderstorm WatchSPCBrown, Callahan, Coleman, Comanche, Concho, Coryell and 23 more6 hr
May 1, 11:07 PM CDTMesoscale DiscussionSPCDimmit, Maverick, Zavala113 min
May 1, 11:44 PM CDTMesoscale DiscussionSPCBell, Bosque, Brown, Burnet, Callahan, Comanche and 22 more2 hr

Nearby

Mesoscale Discussions in Texas, 2022Mesoscale Discussions in Arkansas, 2022Mesoscale Discussions in Oklahoma, 2022Every mesoscale discussion in 2022

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.