Alert archive / Mississippi / Severe Thunderstorm Watches in 2018
Severe Thunderstorm Watch 291
The Storm Prediction Center issued this severe thunderstorm watch at Jul 20, 2018, 2:11 PM CDT for 20 counties in Mississippi. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 20, 2018, 2:11 PM CDT (19:11 UTC)
- Expired
- Jul 20, 2018, 5:24 PM CDT
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
Counties Clarke County, MS, Covington County, MS, Forrest County, MS, Hinds County, MS, Jasper County, MS, Jefferson Davis County, MS, Jones County, MS, Lamar County, MS, Lauderdale County, MS, Lawrence County, MS, Leake County, MS, Madison County, MS, Marion County, MS, Neshoba County, MS, Newton County, MS, Rankin County, MS, Scott County, MS, Simpson County, MS, Smith County, MS, Yazoo County, MS
The radar
The Jackson/Brandon,MS radar (KDGX), 45 km from the middle of the area, began a volume at 19:10 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
- 5%
- One or more EF2 to EF5 tornadoes
- 2%
- 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%
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, 7.2 hours before the alert went out and 55 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
- 1428 J/kg
- Mixed-layer CIN
- -119 J/kg
- Mixed-layer LCL
- 986 m above ground
- 0-6 km bulk shear
- 15 kt
- 0-1 km storm-relative helicity
- 56 m²/s²
- 0-3 km storm-relative helicity
- 153 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 3.7
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 19, 8:02 PM CDT | Mesoscale Discussion | SPC | Coahoma, Tunica | 118 min |
| Jul 19, 8:54 PM CDT | Severe Thunderstorm Watch | SPC | Coahoma, DeSoto, Lafayette, Marshall, Panola, Quitman and 2 more | 114 min |
| Jul 19, 11:21 PM CDT | Mesoscale Discussion | SPC | Attala, Bolivar, Calhoun, Carroll, Coahoma, Grenada and 17 more | 114 min |
| Jul 20, 1:23 PM CDT | Mesoscale Discussion | SPC | Attala, Carroll, Choctaw, Clarke, Copiah, Covington and 20 more | 97 min |
| Jul 20, 5:54 PM CDT | Mesoscale Discussion | SPC | Alcorn, Benton, Chickasaw, Coahoma, DeSoto, Itawamba and 13 more | 3 hr |
| Jul 20, 6:22 PM CDT | Tornado Watch | SPC | Alcorn, Benton, Calhoun, Chickasaw, Coahoma, DeSoto and 16 more | 8 hr |
Nearby
Severe Thunderstorm Watches in Mississippi, 2018Every severe thunderstorm watch in 2018
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.