Alert archive / Louisiana / Severe Thunderstorm Watches in 2021
Severe Thunderstorm Watch 243
The Storm Prediction Center issued this severe thunderstorm watch at Jun 7, 2021, 5:09 PM CDT for Ashley County, Chicot County, Arkansas; 5 parishes in Louisiana; 4 counties in Mississippi. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Jun 7, 2021, 5:09 PM CDT (22:09 UTC)
- Expired
- Jun 7, 2021, 8:04 PM CDT
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1 in
- Strongest gust expected
- 60 kt
Counties Ashley County, AR, Chicot County, AR, East Carroll Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Richland Parish, LA, West Carroll Parish, LA, Bolivar County, MS, Issaquena County, MS, Sharkey County, MS, Washington County, MS
The radar
The Jackson/Brandon,MS radar (KDGX), 173 km from the middle of the area, began a volume at 22:09 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.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 20%
- One or more EF2 to EF5 tornadoes
- 5%
- Ten or more severe wind reports
- 40%
- One or more gusts of 65 knots or more
- 20%
- Ten or more severe hail reports
- 20%
- One or more hailstones of 2 inches or more
- 10%
- Six or more combined severe hail and wind reports
- 60%
Warnings issued inside it
3 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 7, 5:36 PM CDT | Severe Thunderstorm Warning | JAN | Franklin, Morehouse, Richland, West Carroll | 84 min |
| Jun 7, 5:56 PM CDT | Severe Thunderstorm Warning | JAN | Ashley | 43 min |
| Jun 7, 6:23 PM CDT | Severe Thunderstorm Warning | JAN | Chicot | 55 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Jackson, MS (KJAN), launched 12:00Z, 10.2 hours before the alert went out and 164 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
- 723 J/kg
- Mixed-layer CIN
- -14 J/kg
- Mixed-layer LCL
- 564 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 115 m²/s²
- 0-3 km storm-relative helicity
- 93 m²/s²
- Significant tornado parameter
- 0.3
- Supercell composite
- 1.7
The text
As transmitted.
243 WWUS20 KWNS 072207 SEL3 SPC WW 072207 ARZ000-LAZ000-MSZ000-080200- URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 243 NWS Storm Prediction Center Norman OK 510 PM CDT Mon Jun 7 2021 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Extreme southeast Arkansas Extreme northeast Louisiana Extreme west central Mississippi * Effective this Monday afternoon and evening from 510 PM until 900 PM CDT. * Primary threats include... Scattered damaging wind gusts to 70 mph possible Isolated large hail events to 1 inch in diameter possible A tornado or two possible SUMMARY...A line of storms moving eastward across northern Louisiana and southern Arkansas will continue to merge with another band of storms extending eastward into Mississippi. Where the storms merge should be the greater threat for occasional damaging gusts and isolated large hail, as well as an isolated tornado with embedded circulations. The severe thunderstorm watch area is approximately along and 30 statute miles east and west of a line from 35 miles northeast of Monticello AR to 70 miles south southwest of Greenville MS. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU3). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 242... AVIATION...A few severe thunderstorms with hail surface and aloft to 1 inch. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 25025. ...Thompson
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 7, 12:32 PM CDT | Severe Thunderstorm Watch | SPC | Arkansas, Bradley, Calhoun, Clark, Cleveland, Columbia and 21 more | 6 hr |
| Jun 7, 2:16 PM CDT | Mesoscale Discussion | SPC | Clark, Dallas, Garland, Grant, Hempstead, Hot Spring and 8 more | 119 min |
| Jun 7, 3:08 PM CDT | Mesoscale Discussion | SPC | Ashley, Bradley, Columbia, Lafayette, Union | 2 hr |
| Jun 7, 5:23 PM CDT | Mesoscale Discussion | SPC | Ashley, Bradley, Calhoun, Chicot, Cleveland, Dallas and 5 more | 67 min |
Nearby
Severe Thunderstorm Watches in Louisiana, 2021Severe Thunderstorm Watches in Mississippi, 2021Severe Thunderstorm Watches in Arkansas, 2021Every severe thunderstorm watch in 2021
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.