Alert archive / Arkansas / Mesoscale Discussions in 2020
Mesoscale Discussion 1664
The Storm Prediction Center issued this mesoscale discussion at Sep 1, 2020, 5:47 PM CDT for 5 states. It was in force for 88 min.
The area
The outline as issued.
The facts
- Issued
- Sep 1, 2020, 5:47 PM CDT (22:47 UTC)
- Expired
- Sep 1, 2020, 7:15 PM CDT
- In force
- 88 min
- Issued by
- the Storm Prediction Center
- Concerning
- Tornado watch 481
All 59 counties
Arkansas County, AR, Clay County, AR, Cleburne County, AR, Cleveland County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Dallas County, AR, Desha County, AR, Drew County, AR, Faulkner County, AR, Grant County, AR, Greene County, AR, Hot Spring County, AR, Independence County, AR, Izard County, AR, Jackson County, AR, Jefferson County, AR, Lawrence County, AR, Lee County, AR, Lincoln County, AR, Lonoke County, AR, Mississippi County, AR, Monroe County, AR, Phillips County, AR, Poinsett County, AR, Prairie County, AR, Pulaski County, AR, Saline County, AR, Sharp County, AR, St. Francis County, AR, Stone County, AR, White County, AR, Woodruff County, AR, Fulton County, KY, Dunklin County, MO, Pemiscot County, MO, Bolivar County, MS, Coahoma County, MS, DeSoto County, MS, Leflore County, MS, Marshall County, MS, Panola County, MS, Quitman County, MS, Sunflower County, MS, Tallahatchie County, MS, Tate County, MS, Tunica County, MS, Crockett County, TN, Dyer County, TN, Fayette County, TN, Gibson County, TN, Haywood County, TN, Lake County, TN, Lauderdale County, TN, Obion County, TN, Shelby County, TN, Tipton County, TN, Weakley County, TN
The radar
The Memphis radar (KNQA), 104 km from the middle of the area, began a volume at 22:51 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.
The watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Springfield, MO (KSGF), launched 12:00Z, 10.8 hours before the alert went out and 353 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.
- Mixed-layer CAPE
- 38 J/kg
- Mixed-layer CIN
- -101 J/kg
- Mixed-layer LCL
- 987 m above ground
- 0-6 km bulk shear
- 48 kt
- 0-1 km storm-relative helicity
- 34 m²/s²
- 0-3 km storm-relative helicity
- -22 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
The text
As transmitted.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 1, 2:10 PM CDT | Mesoscale Discussion | SPC | Cleburne, Craighead, Crittenden, Cross, Faulkner, Garland and 16 more | 65 min |
| Sep 1, 3:17 PM CDT | Tornado Watch | SPC | Arkansas, Cleburne, Craighead, Crittenden, Cross, Faulkner and 16 more | 4 hr |
| Sep 1, 6:13 PM CDT | Severe Thunderstorm Watch | SPC | Calloway, Fulton, Graves, Hickman | 4 hr |
Nearby
Mesoscale Discussions in Arkansas, 2020Mesoscale Discussions in Mississippi, 2020Mesoscale Discussions in Tennessee, 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.