Alert archive / Arkansas / Mesoscale Discussions in 2018
Mesoscale Discussion 862
The Storm Prediction Center issued this mesoscale discussion at Jun 24, 2018, 4:18 PM CDT for 12 counties in Arkansas; 5 counties in Oklahoma; 9 counties in Texas. It was in force for 117 min.
The area
The outline as issued.
The facts
- Issued
- Jun 24, 2018, 4:18 PM CDT (21:18 UTC)
- Expired
- Jun 24, 2018, 6:15 PM CDT
- In force
- 117 min
- Issued by
- the Storm Prediction Center
All 26 counties
Garland County, AR, Howard County, AR, Little River County, AR, Logan County, AR, Montgomery County, AR, Perry County, AR, Pike County, AR, Polk County, AR, Scott County, AR, Sebastian County, AR, Sevier County, AR, Yell County, AR, Bryan County, OK, Choctaw County, OK, LeFlore County, OK, McCurtain County, OK, Pushmataha County, OK, Bowie County, TX, Delta County, TX, Fannin County, TX, Franklin County, TX, Grayson County, TX, Hopkins County, TX, Lamar County, TX, Red River County, TX, Titus County, TX
The radar
The Western Arkansas radar (KSRX), 118 km from the middle of the area, began a volume at 21:21 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
Shreveport, LA (KBAD), launched 12:00Z, 9.3 hours before the alert went out and 214 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
- 1497 J/kg
- Mixed-layer CIN
- -207 J/kg
- Mixed-layer LCL
- 663 m above ground
- 0-6 km bulk shear
- 6 kt
- 0-1 km storm-relative helicity
- -54 m²/s²
- 0-3 km storm-relative helicity
- 43 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.4
The text
As transmitted.
454
ACUS11 KWNS 242119
SWOMCD
SPC MCD 242118
ARZ000-TXZ000-OKZ000-242315-
Mesoscale Discussion 0862
NWS Storm Prediction Center Norman OK
0418 PM CDT Sun Jun 24 2018
Areas affected...+Southeastern Oklahoma...parts of southwestern
Arkansas...portion of northeast Texas
Concerning...Severe Thunderstorm Watch 212...
Valid 242118Z - 242315Z
The severe weather threat for Severe Thunderstorm Watch 212
continues.
SUMMARY...Storms have intensified across southeast Oklahoma over the
past few hours. At least a narrow area of favorable shear and
instability overlap exists over parts of southwestern Arkansas. An
additional WW is likely in the next hour.
DISCUSSION...Areas of southeast Oklahoma have been able to
destabilize over the course of the day and storms that have moved
into the area have increased in intensity over the last few hours.
Areas downstream of these storms remain moderately unstable with
MLCAPE from 2000-2500 J/kg. KSRX VAD profiles indicate 35-40 kts of
0-6 km shear, however shear decreases with southward extent. With at
least a corridor of favorable overlap between shear and instability
in southwestern Arkansas, a continued threat for severe wind gusts
will remain possible for the next few hours. An additional WW is
likely in the next hour.
..Wendt.. 06/24/2018
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LZK...SHV...TSA...FWD...OUN...
LAT...LON 35439395 35189293 34629278 33929350 33439414 33149515
33139628 33439692 34289622 34799523 35439395SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 24, 2:33 AM CDT | Mesoscale Discussion | SPC | Cleburne, Crittenden, Cross, Faulkner, Independence, Jackson and 11 more | 87 min |
| Jun 24, 5:11 AM CDT | Mesoscale Discussion | SPC | Crawford, Franklin, Johnson, Logan, Montgomery, Perry and 6 more | 79 min |
| Jun 24, 5:28 AM CDT | Severe Thunderstorm Watch | SPC | Clark, Conway, Crawford, Franklin, Garland, Hempstead and 17 more | 4 hr |
| Jun 24, 7:37 AM CDT | Mesoscale Discussion | SPC | Arkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 47 more | 113 min |
| Jun 24, 4:53 PM CDT | Severe Thunderstorm Watch | SPC | Bradley, Calhoun, Clark, Cleveland, Columbia, Dallas and 22 more | 6 hr |
| Jun 24, 6:39 PM CDT | Mesoscale Discussion | SPC | Clay, Cleburne, Craighead, Cross, Greene, Independence and 6 more | 2 hr |
| Jun 23, 7:50 PM CDT | Mesoscale Discussion | SPC | Beckham, Blaine, Caddo, Canadian, Carter, Cleveland and 24 more | 55 min |
| Jun 23, 9:32 PM CDT | Mesoscale Discussion | SPC | Alfalfa, Beaver, Blaine, Canadian, Custer, Dewey and 16 more | 118 min |
| Jun 23, 9:52 PM CDT | Severe Thunderstorm Watch | SPC | Alfalfa, Beaver, Blaine, Custer, Dewey, Ellis and 13 more | 7 hr |
| Jun 24, 1:25 AM CDT | Mesoscale Discussion | SPC | Alfalfa, Beaver, Blaine, Canadian, Cleveland, Creek and 25 more | 95 min |
| Jun 24, 3:23 AM CDT | Severe Thunderstorm Watch | SPC | Canadian, Cherokee, Creek, Haskell, Hughes, Latimer and 19 more | 6 hr |
| Jun 24, 7:17 AM CDT | Mesoscale Discussion | SPC | Alfalfa, Beaver, Beckham, Blaine, Caddo, Canadian and 14 more | 118 min |
| Jun 24, 12:57 PM CDT | Mesoscale Discussion | SPC | Caddo, Canadian, Carter, Cleveland, Comanche, Cotton and 15 more | 93 min |
| Jun 24, 2:40 PM CDT | Severe Thunderstorm Watch | SPC | Atoka, Bryan, Carter, Choctaw, Coal, Garvin and 15 more | 5 hr |
| Jun 24, 3:04 PM CDT | Mesoscale Discussion | SPC | Cimarron | 86 min |
| Jun 23, 8:33 PM CDT | Mesoscale Discussion | SPC | Coke, Fisher, Haskell, Jones, Mitchell, Nolan and 4 more | 117 min |
| Jun 24, 1:53 AM CDT | Mesoscale Discussion | SPC | Bosque, Comanche, Dallas, Eastland, Ellis, Erath and 12 more | 67 min |
| Jun 24, 5:50 PM CDT | Mesoscale Discussion | SPC | Fisher, Glasscock, Howard, Kent, Mitchell, Reagan and 4 more | 115 min |
Nearby
Mesoscale Discussions in Arkansas, 2018Mesoscale Discussions in Texas, 2018Mesoscale Discussions in Oklahoma, 2018Every mesoscale discussion 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.