Alert archive / Arkansas / Severe Thunderstorm Watches in 2018
Severe Thunderstorm Watch 293
The Storm Prediction Center issued this severe thunderstorm watch at Jul 20, 2018, 3:58 PM CDT for 14 counties in Arkansas; 10 counties in Missouri. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 20, 2018, 3:58 PM CDT (20:58 UTC)
- Expired
- Jul 20, 2018, 10:00 PM CDT
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 3 in
- Strongest gust expected
- 60 kt
All 24 counties
Baxter County, AR, Clay County, AR, Craighead County, AR, Cross County, AR, Fulton County, AR, Greene County, AR, Independence County, AR, Izard County, AR, Jackson County, AR, Lawrence County, AR, Poinsett County, AR, Randolph County, AR, Sharp County, AR, Stone County, AR, Butler County, MO, Carter County, MO, Douglas County, MO, Howell County, MO, Oregon County, MO, Ozark County, MO, Ripley County, MO, Shannon County, MO, Texas County, MO, Wright County, MO
The radar
The Springfield radar (KSGF), 173 km from the middle of the area, began a volume at 21:03 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
- 80%
- One or more gusts of 65 knots or more
- 20%
- Ten or more severe hail reports
- 80%
- One or more hailstones of 2 inches or more
- 40%
- Six or more combined severe hail and wind reports
- 95%
Warnings issued inside it
5 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 20, 4:44 PM CDT | Severe Thunderstorm Warning | SGF | Howell, Shannon, Texas | 33 min |
| Jul 20, 4:49 PM CDT | Severe Thunderstorm Warning | SGF | Shannon | 29 min |
| Jul 20, 4:51 PM CDT | Severe Thunderstorm Warning | PAH | Carter | 24 min |
| Jul 20, 5:07 PM CDT | Severe Thunderstorm Warning | PAH | Carter | 26 min |
| Jul 20, 6:05 PM CDT | Severe Thunderstorm Warning | PAH | Butler, Stoddard | 25 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
Springfield, MO (KSGF), launched 12:00Z, 9.0 hours before the alert went out and 195 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
- 1151 J/kg
- Mixed-layer CIN
- -259 J/kg
- Mixed-layer LCL
- 1847 m above ground
- 0-6 km bulk shear
- 53 kt
- 0-1 km storm-relative helicity
- 197 m²/s²
- 0-3 km storm-relative helicity
- 203 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 2.1
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 19, 7:07 PM CDT | Severe Thunderstorm Watch | SPC | Baxter, Boone, Carroll, Cleburne, Fulton, Independence and 10 more | 3 hr |
| Jul 19, 8:02 PM CDT | Mesoscale Discussion | SPC | Arkansas, Baxter, Clark, Cleburne, Cleveland, Conway and 40 more | 118 min |
| Jul 19, 8:54 PM CDT | Severe Thunderstorm Watch | SPC | Arkansas, Bradley, Calhoun, Clark, Clay, Cleveland and 35 more | 114 min |
| Jul 19, 11:21 PM CDT | Mesoscale Discussion | SPC | Chicot, Desha, Phillips | 114 min |
| Jul 20, 9:25 AM CDT | Mesoscale Discussion | SPC | Arkansas, Cleburne, Crittenden, Cross, Faulkner, Independence and 13 more | 2 hr |
| Jul 20, 12:58 PM CDT | Mesoscale Discussion | SPC | Clay | 62 min |
| Jul 20, 3:46 PM CDT | Mesoscale Discussion | SPC | Baxter, Boone, Fulton, Izard, Marion, Randolph and 2 more | 59 min |
| Jul 20, 5:54 PM CDT | Mesoscale Discussion | SPC | Crittenden, Lee, Phillips, St. Francis | 3 hr |
| Jul 20, 6:22 PM CDT | Tornado Watch | SPC | Crittenden, Lee, Mississippi, Phillips, St. Francis | 8 hr |
| Jul 19, 9:36 PM CDT | Mesoscale Discussion | SPC | Clark, Knox, Lewis, Lincoln, Marion, Pike and 3 more | 54 min |
Nearby
Severe Thunderstorm Watches in Arkansas, 2018Severe Thunderstorm Watches in Missouri, 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.