Alert archive / Arkansas / Mesoscale Discussions in 2022
Mesoscale Discussion 1821
The Storm Prediction Center issued this mesoscale discussion at Sep 24, 2022, 4:35 PM CDT for 8 counties in Arkansas; 8 counties in Missouri; 4 counties in Tennessee. It was in force for 115 min.
The area
The outline as issued.
The facts
- Issued
- Sep 24, 2022, 4:35 PM CDT (21:35 UTC)
- Expired
- Sep 24, 2022, 6:30 PM CDT
- In force
- 115 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch unlikely
- Chance of a watch
- 20%
Counties Clay County, AR, Craighead County, AR, Fulton County, AR, Greene County, AR, Lawrence County, AR, Mississippi County, AR, Randolph County, AR, Sharp County, AR, Butler County, MO, Douglas County, MO, Dunklin County, MO, Howell County, MO, Oregon County, MO, Ozark County, MO, Pemiscot County, MO, Ripley County, MO, Dyer County, TN, Lake County, TN, Lauderdale County, TN, Obion County, TN
The radar
The Memphis radar (KNQA), 171 km from the middle of the area, began a volume at 21:35 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 nearest sounding before it
Little Rock, AR (KLZK), launched 12:00Z, 9.6 hours before the alert went out and 216 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1269 m above ground
- 0-6 km bulk shear
- 33 kt
- 0-1 km storm-relative helicity
- 158 m²/s²
- 0-3 km storm-relative helicity
- 233 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
376 ACUS11 KWNS 242136 SWOMCD SPC MCD 242135 TNZ000-KYZ000-MOZ000-ARZ000-242330- Mesoscale Discussion 1821 NWS Storm Prediction Center Norman OK 0435 PM CDT Sat Sep 24 2022 Areas affected...Southern Missouri to western Tennessee Concerning...Severe potential...Watch unlikely Valid 242135Z - 242330Z Probability of Watch Issuance...20 percent SUMMARY...Isolated risk for wind/hail exists with convection across southern Missouri into western Tennessee this evening. DISCUSSION...Convection is gradually deepening along a surface boundary that has sagged into southern MO. This activity is evolving along the northern fringe of thicker cloud cover where differential heating appears to be maximized in/near the surface boundary. Latest diagnostic data suggests a corridor of 1000-1500 J/kg MLCAPE extends across the MO Ozarks into extreme western TN. It appears thunderstorms could continue to increase in coverage/intensity and spread southeast within modestly sheared environment that seemingly favors organized updrafts. Primary risk with this activity should be isolated hail/wind. Current thinking is the severe threat will remain too sparse/marginal to warrant a severe thunderstorm watch, but trends will continue to be monitored. ..Darrow/Hart.. 09/24/2022 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PAH...MEG...LZK...SGF... LAT...LON 37329224 36418913 35608930 35789077 36809279 37329224
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 24, 2:55 PM CDT | Mesoscale Discussion | SPC | Conway, Faulkner, Garland, Hot Spring, Logan, Lonoke and 8 more | 3 hr |
Nearby
Mesoscale Discussions in Arkansas, 2022Mesoscale Discussions in Missouri, 2022Mesoscale Discussions in Tennessee, 2022Every mesoscale discussion in 2022
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.