Alert archive / Arkansas / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 221, NWS Shreveport, LA

December 29, 2021Columbia County, Union County, Arkansas; Claiborne Parish, Webster Parish, Louisiana

NWS Shreveport, LA issued this severe thunderstorm warning at Dec 29, 2021, 1:33 PM CST for Columbia County, Union County, Arkansas; Claiborne Parish, Webster Parish, Louisiana. It was in force for 42 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Dec 29, 2021, 1:33 PM CST (19:33 UTC)
Expired
Dec 29, 2021, 2:15 PM CST
In force
42 min
Issued by
NWS Shreveport, LA
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Columbia County, AR, Union County, AR, Claiborne Parish, LA, Webster Parish, LA

The radar

The Shreveport radar (KSHV), 88 km from the middle of the area, began a volume at 19:37 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Dec 29, 12:05 PM CSTTornado WatchSPC7 hr

The nearest sounding before it

Shreveport, LA (KSHV), launched 12:00Z, 7.6 hours before the alert went out and 80 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 2021-12-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 272 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 2021-12-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 146 square meters per square second.1939587897Sfc1 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
272 J/kg
Mixed-layer CIN
-90 J/kg
Mixed-layer LCL
687 m above ground
0-6 km bulk shear
65 kt
0-1 km storm-relative helicity
146 m²/s²
0-3 km storm-relative helicity
-4 m²/s²
Significant tornado parameter
0.2
Supercell composite
2.5

Open this sounding in Storm Lab

The text

As transmitted.

524 
WUUS54 KSHV 291933
SVRSHV
ARC027-139-LAC027-119-292015-
/O.NEW.KSHV.SV.W.0221.211229T1933Z-211229T2015Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Shreveport LA
133 PM CST Wed Dec 29 2021

The National Weather Service in Shreveport has issued a

* Severe Thunderstorm Warning for...
  Southwestern Union County in south central Arkansas...
  Southeastern Columbia County in southwestern Arkansas...
  North central Webster Parish in northwestern Louisiana...
  Northern Claiborne Parish in northwestern Louisiana...

* Until 215 PM CST.

* At 133 PM CST, a severe thunderstorm was located near Shongaloo, or
  12 miles east of Springhill, moving northeast at 35 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* Locations impacted include...
  Haynesville, Shongaloo, Atlanta, Hew Hope, Leton and Three Creeks. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 700 PM CST for south central
Arkansas...and northwestern Louisiana.

For your protection move to an interior room on the lowest floor of a
building.

A Tornado Watch remains in effect until 700 PM CST for south central
Arkansas...and northwestern Louisiana.

&&

LAT...LON 3285 9329 3299 9337 3323 9293 3295 9278
TIME...MOT...LOC 1933Z 246DEG 32KT 3297 9325 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

/26/
1 follow-up statement
453 
WWUS54 KSHV 291955
SVSSHV

Severe Weather Statement
National Weather Service Shreveport LA
155 PM CST Wed Dec 29 2021

LAC119-292004-
/O.CAN.KSHV.SV.W.0221.000000T0000Z-211229T2015Z/
Webster LA-
155 PM CST Wed Dec 29 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL WEBSTER PARISH
IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Tornado Watch remains in effect until 700 PM CST for south central
Arkansas...and northwestern Louisiana.

LAT...LON 3292 9311 3310 9317 3323 9293 3295 9278
TIME...MOT...LOC 1954Z 246DEG 32KT 3305 9304 

$$

ARC027-139-LAC027-292015-
/O.CON.KSHV.SV.W.0221.000000T0000Z-211229T2015Z/
Union AR-Columbia AR-Claiborne LA-
155 PM CST Wed Dec 29 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 215 PM CST
FOR SOUTHWESTERN UNION...SOUTHEASTERN COLUMBIA COUNTIES IN
SOUTHWESTERN ARKANSAS AND NORTHEASTERN CLAIBORNE PARISHES...

At 154 PM CST, a severe thunderstorm was located over Atlanta, or 17
miles north of Homer, moving northeast at 35 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

Locations impacted include...
Haynesville, Atlanta, Hew Hope and Three Creeks. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 700 PM CST for south central
Arkansas...and northwestern Louisiana.

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3292 9311 3310 9317 3323 9293 3295 9278
TIME...MOT...LOC 1954Z 246DEG 32KT 3305 9304 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

/26/

The office that day

Everything else NWS Shreveport, LA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 29, 9:43 AM CSTSpecial Weather StatementSHVHoward, Sevier32 min
Dec 29, 1:15 PM CSTSpecial Weather StatementSHVColumbia30 min
Dec 29, 2:11 PM CSTSpecial Weather StatementSHVUnion34 min
Dec 29, 4:23 PM CSTSpecial Weather StatementSHVUnion52 min
Dec 29, 4:32 PM CSTSpecial Weather StatementSHVHempstead43 min
Dec 29, 4:35 PM CSTSpecial Weather StatementSHVMiller40 min
Dec 29, 5:15 PM CSTSpecial Weather StatementSHVNevada30 min
Dec 29, 12:51 PM CSTSpecial Weather StatementSHVBossier24 min

Nearby

Severe Thunderstorm Warnings in Arkansas, 2021Severe Thunderstorm Warnings in Louisiana, 2021Every severe thunderstorm warning 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.