Alert archive / Arkansas / Tornado Warnings in 2017

Tornado Warning 56, NWS Shreveport, LA

April 21, 2017Hempstead County, Howard County, Sevier County, Arkansas

NWS Shreveport, LA issued this tornado warning at Apr 21, 2017, 11:47 PM CDT for Hempstead County, Howard County, Sevier County, Arkansas. It was in force for 43 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Apr 21, 2017, 11:47 PM CDT (04:47 UTC)
Expired
Apr 22, 2017, 12:30 AM CDT
In force
43 min
Issued by
NWS Shreveport, LA
Area
Storm-based polygon
Tornado
Radar indicated
Hail
1.0 in

Counties Hempstead County, AR, Howard County, AR, Sevier County, AR

The radar

The Shreveport radar (KSHV), 152 km from the middle of the area, began a volume at 04:49 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.

What was reported inside it

TimeReportWhereRemark
Apr 22, 12:03 AM CDTHAIL 13 E Tollette, AR

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

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

IssuedProductOfficeLasted
Apr 21, 4:40 PM CDTTornado WatchSPC8 hr

The nearest sounding before it

Shreveport, LA (KBAD), launched 00:00Z, 4.8 hours before the alert went out and 149 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 00:00Z on 2017-04-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 828 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 00:00Z on 2017-04-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 75 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
828 J/kg
Mixed-layer CIN
-29 J/kg
Mixed-layer LCL
1486 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
75 m²/s²
0-3 km storm-relative helicity
143 m²/s²
Significant tornado parameter
0.2
Supercell composite
4.5

Open this sounding in Storm Lab

The text

As transmitted.

318 
WFUS54 KSHV 220447
TORSHV
ARC057-061-133-220530-
/O.NEW.KSHV.TO.W.0056.170422T0447Z-170422T0530Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Shreveport LA
1147 PM CDT FRI APR 21 2017

The National Weather Service in Shreveport has issued a

* Tornado Warning for...
  North central Hempstead County in southwestern Arkansas...
  Southeastern Sevier County in southwestern Arkansas...
  Southeastern Howard County in southwestern Arkansas...

* Until 1230 AM CDT
    
* At 1147 PM CDT, a severe thunderstorm capable of producing a
  tornado was located near Ben Lomond, or 8 miles southwest of
  Mineral Springs, moving east at 30 mph.

  HAZARD...Tornado and quarter size hail. 

  SOURCE...Radar indicated rotation. 

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely. 

* Locations impacted include...
  Mineral Springs, Tollette, Ben Lomond, Saratoga and Browntown. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 3390 9377 3374 9378 3376 9398 3377 9404
      3378 9404 3378 9407 3379 9411 3387 9411
TIME...MOT...LOC 0447Z 272DEG 25KT 3382 9405 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

06
1 follow-up statement
749 
WWUS54 KSHV 220511
SVSSHV

Severe Weather Statement
National Weather Service Shreveport LA
1211 AM CDT SAT APR 22 2017

ARC133-220520-
/O.CAN.KSHV.TO.W.0056.000000T0000Z-170422T0530Z/
Sevier AR-
1211 AM CDT SAT APR 22 2017

...THE TORNADO WARNING FOR SOUTHEASTERN SEVIER COUNTY IS CANCELLED...
    
The tornadic 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 100 AM CDT for southwestern
Arkansas.

LAT...LON 3390 9377 3374 9378 3376 9389 3379 9394
      3382 9396 3389 9393
TIME...MOT...LOC 0510Z 271DEG 24KT 3382 9389 

$$

ARC057-061-220530-
/O.CON.KSHV.TO.W.0056.000000T0000Z-170422T0530Z/
Hempstead AR-Howard AR-
1211 AM CDT SAT APR 22 2017

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 1230 AM CDT FOR NORTH
CENTRAL HEMPSTEAD AND SOUTHEASTERN HOWARD COUNTIES...
    
At 1210 AM CDT, a severe thunderstorm capable of producing a tornado
was located over Tollette, or near Mineral Springs, moving east at 25
mph.

HAZARD...Tornado and quarter size hail. 

SOURCE...Radar indicated rotation. 

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely. 

Locations impacted include...
Mineral Springs and Tollette. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Tornadoes are extremely difficult to see and confirm at night. Do not
wait to see or hear the tornado. TAKE COVER NOW!

&&

LAT...LON 3390 9377 3374 9378 3376 9389 3379 9394
      3382 9396 3389 9393
TIME...MOT...LOC 0510Z 271DEG 24KT 3382 9389 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

06

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 21, 9:52 PM CDTLake Wind AdvisorySHVColumbia, Hempstead, Howard, Lafayette, Little River, Miller and 3 more17 hr
Apr 21, 10:46 PM CDTSevere Thunderstorm WarningSHVLittle River, Sevier59 min
Apr 21, 11:24 PM CDTSevere Thunderstorm WarningSHVHempstead, Howard, Little River, Sevier66 min
Apr 21, 11:41 PM CDTSpecial Weather StatementSHVLittle River49 min
Apr 22, 12:30 AM CDTSevere Thunderstorm WarningSHVHempstead, Nevada60 min
Apr 22, 12:39 AM CDTSpecial Weather StatementSHVLittle River36 min
Apr 22, 12:45 AM CDTSpecial Weather StatementSHVSevier45 min
Apr 22, 1:33 AM CDTSpecial Weather StatementSHVHempstead42 min
Apr 22, 2:18 AM CDTSpecial Weather StatementSHVHempstead42 min

Nearby

Tornado Warnings in Arkansas, 2017Every tornado warning in 2017Tornadoes in 2017

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.