Alert archive / Texas / Mesoscale Discussions in 2021

Mesoscale Discussion 882

June 8, 2021Bossier Parish, Caddo Parish, Louisiana; 6 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Jun 8, 2021, 10:11 AM CDT for Bossier Parish, Caddo Parish, Louisiana; 6 counties in Texas. It was in force for 64 min.

The area

The outline as issued.

The facts

Issued
Jun 8, 2021, 10:11 AM CDT (15:11 UTC)
Expired
Jun 8, 2021, 11:15 AM CDT
In force
64 min
Issued by
the Storm Prediction Center
Concerning
Severe potential...watch unlikely
Chance of a watch
20%

Counties Bossier Parish, LA, Caddo Parish, LA, Cherokee County, TX, Gregg County, TX, Harrison County, TX, Marion County, TX, Panola County, TX, Rusk County, TX

The radar

The Shreveport radar (KSHV), 53 km from the middle of the area, began a volume at 15:13 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, 3.2 hours before the alert went out and 62 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.

Skew-T log-pSkew-T log-p diagram, Shreveport, LA at 12:00Z on 2021-06-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1621 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Shreveport, LA at 12:00Z on 2021-06-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 106 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1621 J/kg
Mixed-layer CIN
-10 J/kg
Mixed-layer LCL
580 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
106 m²/s²
0-3 km storm-relative helicity
218 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.1

Open this sounding in Storm Lab

The text

As transmitted.

876 
ACUS11 KWNS 081511
SWOMCD
SPC MCD 081511 
LAZ000-TXZ000-081615-

Mesoscale Discussion 0882
NWS Storm Prediction Center Norman OK
1011 AM CDT Tue Jun 08 2021

Areas affected...northeast TX...northwest LA

Concerning...Severe potential...Watch unlikely 

Valid 081511Z - 081615Z

Probability of Watch Issuance...20 percent

SUMMARY...The airmass over northeast TX and northwest LA will
continue to slowly destabilize this morning ahead of an approaching
squall line.  An isolated risk for damaging gusts may eventually
materialize this afternoon across northern LA.

DISCUSSION...Radar mosaic at 10am CDT shows a squall line moving
east across northeast TX.  During the past hour, measured gusts have
at ASOS sites have remained below 25 kt.  However, gradual heating
and associated destabilization is expected to occur across adjacent
portions of northeast TX into northern LA later this morning into
the early afternoon.  The Shreveport, LA 88D VAD data shows flow in
the 30-35 kt range in the 1-3 km AGL layer.  This enhanced belt of
flow coupled with the possibility for squall line intensification
towards midday may result in the threat for wind damage to increase
mainly for portions of northern LA.  Will monitor convective trends
in the short term for signs of storm intensification and the
possibility for a watch later today.  An upgrade to 15-percent wind
probabilities and a categorical Slight Risk is anticipated for
portions of northern LA for the upcoming 1630z Day 1 outlook.

..Smith/Guyer.. 06/08/2021

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...SHV...

LAT...LON   32609511 33049430 32929363 32299347 31869398 31639525
            32609511

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 8, 11:17 AM CDTMesoscale DiscussionSPCBienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 14 more118 min
Jun 8, 12:42 PM CDTSevere Thunderstorm WatchSPCBienville, Caldwell, Claiborne, East Carroll, Franklin, Jackson and 11 more6 hr
Jun 8, 2:47 PM CDTMesoscale DiscussionSPCCaldwell, East Carroll, Franklin, Madison, Richland, West Carroll118 min
Jun 7, 7:03 PM CDTMesoscale DiscussionSPCBailey, Borden, Castro, Cochran, Crosby, Dawson and 16 more2 hr
Jun 7, 9:04 PM CDTSevere Thunderstorm WatchSPCBriscoe, Castro, Childress, Cottle, Crosby, Dickens and 7 more5 hr
Jun 7, 10:28 PM CDTMesoscale DiscussionSPCBriscoe, Castro, Cottle, Crosby, Dickens, Floyd and 10 more92 min
Jun 8, 1:11 AM CDTMesoscale DiscussionSPCBaylor, Fisher, Haskell, Jones, Kent, King and 6 more2 hr
Jun 8, 4:53 AM CDTMesoscale DiscussionSPCBandera, Blanco, Burnet, Comal, Gillespie, Hays and 9 more2 hr

Nearby

Mesoscale Discussions in Texas, 2021Mesoscale Discussions in Louisiana, 2021Every mesoscale discussion in 2021

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.