Alert archive / Oklahoma / Mesoscale Discussions in 2020

Mesoscale Discussion 433

April 22, 202013 counties in Oklahoma; Fannin County, Lamar County, Red River County, Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 22, 2020, 1:21 AM CDT for 13 counties in Oklahoma; Fannin County, Lamar County, Red River County, Texas. It was in force for 84 min.

The area

The outline as issued.

The facts

Issued: Apr 22, 2020, 1:21 AM CDT (06:21 UTC)
Expired: Apr 22, 2020, 2:45 AM CDT
In force: 84 min
Issued by: the Storm Prediction Center

Counties Atoka County, OK, Bryan County, OK, Carter County, OK, Choctaw County, OK, Coal County, OK, Garvin County, OK, Johnston County, OK, Marshall County, OK, McCurtain County, OK, Murray County, OK, Pontotoc County, OK, Pushmataha County, OK, Stephens County, OK, Fannin County, TX, Lamar County, TX, Red River County, TX

The radar

The Norman radar (KTLX), 169 km from the middle of the area, began a volume at 06:22 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Severe Thunderstorm Watch 131Apr 22, 1:45 AM CDT

The nearest sounding before it

Norman, OK (KOUN), launched 00:00Z, 6.4 hours before the alert went out and 168 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 46 J/kg
Mixed-layer CIN: -146 J/kg
Mixed-layer LCL: 2104 m above ground
0-6 km bulk shear: 71 kt
0-1 km storm-relative helicity: 18 m²/s²
0-3 km storm-relative helicity: 279 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

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.

Issued	Product	Office	Counties	Lasted
Apr 21, 9:10 PM CDT	Mesoscale Discussion	SPC	Beckham, Blaine, Caddo, Canadian, Carter, Cleveland and 24 more	95 min
Apr 21, 11:32 PM CDT	Mesoscale Discussion	SPC	Beckham, Blaine, Caddo, Canadian, Carter, Cleveland and 24 more	88 min
Apr 22, 1:46 AM CDT	Severe Thunderstorm Watch	SPC	Atoka, Bryan, Carter, Choctaw, Garvin, Johnston and 6 more	4 hr
Apr 22, 2:16 AM CDT	Mesoscale Discussion	SPC	Beaver, Ellis, Harper, Texas, Woods, Woodward	119 min
Apr 22, 8:36 AM CDT	Mesoscale Discussion	SPC	Atoka, Blaine, Caddo, Canadian, Carter, Cleveland and 26 more	84 min
Apr 22, 8:53 AM CDT	Severe Thunderstorm Watch	SPC	Adair, Atoka, Bryan, Caddo, Canadian, Carter and 46 more	6 hr
Apr 22, 11:29 AM CDT	Mesoscale Discussion	SPC	Atoka, Coal, Haskell, Hughes, Latimer, LeFlore and 5 more	91 min
Apr 22, 1:12 PM CDT	Mesoscale Discussion	SPC	Atoka, Bryan, Carter, Choctaw, Coal, Garvin and 7 more	63 min
Apr 22, 2:33 PM CDT	Tornado Watch	SPC	Atoka, Bryan, Carter, Choctaw, Coal, Garvin and 11 more	6 hr
Apr 22, 4:43 PM CDT	Mesoscale Discussion	SPC	Atoka, Bryan, Coal, Garvin, Johnston, Marshall and 2 more	62 min
Apr 22, 6:39 PM CDT	Mesoscale Discussion	SPC	McCurtain	66 min
Apr 21, 8:12 PM CDT	Mesoscale Discussion	SPC	Hemphill, Lipscomb, Wheeler	63 min
Apr 22, 10:38 AM CDT	Mesoscale Discussion	SPC	Anderson, Angelina, Austin, Bastrop, Bell, Blanco and 50 more	2 hr
Apr 22, 10:55 AM CDT	Tornado Watch	SPC	Anderson, Angelina, Austin, Bastrop, Brazos, Burleson and 31 more	6 hr
Apr 22, 1:10 PM CDT	Mesoscale Discussion	SPC	Anderson, Angelina, Austin, Bastrop, Bell, Brazos and 35 more	65 min
Apr 22, 2:53 PM CDT	Mesoscale Discussion	SPC	Anderson, Angelina, Cherokee, Houston, Nacogdoches, Panola and 5 more	67 min
Apr 22, 4:24 PM CDT	Mesoscale Discussion	SPC	Angelina, Brazos, Cherokee, Grimes, Hardin, Houston and 14 more	96 min
Apr 22, 4:47 PM CDT	Mesoscale Discussion	SPC	Angelina, Polk, San Augustine, San Jacinto, Trinity, Tyler and 1 more	88 min
Apr 22, 5:01 PM CDT	Tornado Watch	SPC	Angelina, Cherokee, Grimes, Harrison, Houston, Jasper and 14 more	9 hr
Apr 22, 5:38 PM CDT	Mesoscale Discussion	SPC	Camp, Collin, Dallas, Delta, Fannin, Franklin and 10 more	97 min
Apr 22, 5:53 PM CDT	Mesoscale Discussion	SPC	Angelina, Polk, Trinity, Tyler	37 min

Nearby

Mesoscale Discussions in Oklahoma, 2020 Mesoscale Discussions in Texas, 2020 Every 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.