Alert archive / Louisiana / Mesoscale Discussions in 2023
Mesoscale Discussion 708
The Storm Prediction Center issued this mesoscale discussion at May 7, 2023, 1:33 PM CDT for 5 counties in Arkansas; 18 parishes in Louisiana; 5 counties in Texas. It was in force for 87 min.
The area
The outline as issued.
The facts
- Issued
- May 7, 2023, 1:33 PM CDT (18:33 UTC)
- Expired
- May 7, 2023, 3:00 PM CDT
- In force
- 87 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch unlikely
- Chance of a watch
- 20%
All 28 counties
Columbia County, AR, Lafayette County, AR, Miller County, AR, Ouachita County, AR, Union County, AR, Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Caldwell Parish, LA, Claiborne Parish, LA, De Soto Parish, LA, Grant Parish, LA, Jackson Parish, LA, LaSalle Parish, LA, Lincoln Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Red River Parish, LA, Sabine Parish, LA, Union Parish, LA, Vernon Parish, LA, Webster Parish, LA, Winn Parish, LA, Harrison County, TX, Panola County, TX, Sabine County, TX, San Augustine County, TX, Shelby County, TX
The radar
The Shreveport radar (KSHV), 59 km from the middle of the area, began a volume at 18:33 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
Shreveport, LA (KSHV), launched 12:00Z, 6.6 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
- 596 J/kg
- Mixed-layer CIN
- -437 J/kg
- Mixed-layer LCL
- 932 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- 128 m²/s²
- 0-3 km storm-relative helicity
- 134 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
567
ACUS11 KWNS 071834
SWOMCD
SPC MCD 071833
LAZ000-ARZ000-TXZ000-072000-
Mesoscale Discussion 0708
NWS Storm Prediction Center Norman OK
0133 PM CDT Sun May 07 2023
Areas affected...east Texas...northwest Louisiana...and far southern
Arkansas.
Concerning...Severe potential...Watch unlikely
Valid 071833Z - 072000Z
Probability of Watch Issuance...20 percent
SUMMARY...A few strong to potentially severe storms are possible
this afternoon/evening in the ArkLaTex.
DISCUSSION...A broad region of stratiform rain exists across the
Texas Gulf Coast which is remnant from overnight convection spawned
by a mid-level shortwave trough moving through the region. Ahead of
this shortwave trough, sufficient warming has occurred across east
Texas, northern Louisiana, and far southern Arkansas to erode
inhibition. Therefore, as weak ascent ahead of this mid-level trough
has been sufficient for storm development across east Texas. Despite
filtered sun, at least some continued heating is expected with
MLCAPE potentially peaking around 3000 J/kg.
Shear is weak across the region (20 to 25 knots per SPC
mesoanalysis) which will limit storm organization and the overall
severe threat. However, steep lapse rates and strong instability
will be sufficient for some threat for strong to severe storms with
a threat for large hail and damaging wind gusts.
..Bentley/Hart.. 05/07/2023
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...JAN...LZK...LCH...SHV...
LAT...LON 31089415 31509440 32199446 33459423 33639300 33519237
32959195 31999184 31249254 30999347 31089415SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 6, 8:31 PM CDT | Mesoscale Discussion | SPC | Archer, Baylor, Brown, Callahan, Clay, Coleman and 19 more | 119 min |
| May 6, 9:39 PM CDT | Severe Thunderstorm Watch | SPC | Bosque, Collin, Comanche, Dallas, Delta, Denton and 23 more | 5 hr |
| May 6, 11:13 PM CDT | Mesoscale Discussion | SPC | Dallas, Ellis, Hill, Johnson, Kaufman, Rockwall and 1 more | 92 min |
| May 7, 1:55 PM CDT | Mesoscale Discussion | SPC | Archer, Baylor, Borden, Callahan, Clay, Coke and 28 more | 95 min |
| May 7, 2:55 PM CDT | Severe Thunderstorm Watch | SPC | Archer, Baylor, Borden, Brown, Callahan, Coke and 34 more | 6 hr |
| May 7, 4:52 PM CDT | Mesoscale Discussion | SPC | Dimmit, Edwards, Kinney, Maverick, Uvalde, Val Verde and 3 more | 2 hr |
| May 7, 5:23 PM CDT | Mesoscale Discussion | SPC | Baylor, Fisher, Foard, Haskell, Jones, King and 6 more | 97 min |
Nearby
Mesoscale Discussions in Louisiana, 2023Mesoscale Discussions in Arkansas, 2023Mesoscale Discussions in Texas, 2023Every mesoscale discussion in 2023
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.