Alert archive / Arkansas / Tornado Watches in 2015

Tornado Watch 161

May 10, 201519 counties in Arkansas; McCurtain County, Oklahoma; 15 counties in Texas

The Storm Prediction Center issued this tornado watch at May 10, 2015, 7:34 PM CDT for 19 counties in Arkansas; McCurtain County, Oklahoma; 15 counties in Texas. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
May 10, 2015, 7:34 PM CDT (00:34 UTC)
Expired
May 11, 2015, 12:00 AM CDT
In force
4 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 35 counties

Clark County, AR, Dallas County, AR, Garland County, AR, Grant County, AR, Hempstead County, AR, Hot Spring County, AR, Howard County, AR, Lafayette County, AR, Little River County, AR, Miller County, AR, Montgomery County, AR, Nevada County, AR, Perry County, AR, Pike County, AR, Polk County, AR, Saline County, AR, Scott County, AR, Sevier County, AR, Yell County, AR, McCurtain County, OK, Bowie County, TX, Camp County, TX, Cass County, TX, Cherokee County, TX, Franklin County, TX, Gregg County, TX, Harrison County, TX, Marion County, TX, Morris County, TX, Red River County, TX, Rusk County, TX, Smith County, TX, Titus County, TX, Upshur County, TX, Wood County, TX

The radar

The Shreveport radar (KSHV), 159 km from the middle of the area, began a volume at 00:37 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.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
40%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
10%
Ten or more severe hail reports
30%
One or more hailstones of 2 inches or more
30%
Six or more combined severe hail and wind reports
60%

Warnings issued inside it

25 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
May 10, 8:03 PM CDTTornado WarningSHVSevier42 min
May 10, 8:23 PM CDTSevere Thunderstorm WarningLZKPolk37 min
May 10, 8:33 PM CDTTornado WarningSHVHoward, Sevier38 min
May 10, 8:55 PM CDTFlash Flood WarningLZKGarland, Johnson, Logan, Montgomery, Newton, Perry and 4 more3 hr
May 10, 9:07 PM CDTSevere Thunderstorm WarningSHVSmith, Wood53 min
May 10, 9:26 PM CDTTornado WarningSHVSmith, Wood29 min
May 10, 9:54 PM CDTTornado WarningLZKMontgomery, Polk, Scott, Yell36 min
May 10, 10:06 PM CDTSevere Thunderstorm WarningSHVHempstead, Howard, Little River, Sevier39 min
May 10, 10:16 PM CDTSevere Thunderstorm WarningSHVSmith, Upshur, Wood59 min
May 10, 10:19 PM CDTTornado WarningSHVHempstead, Little River26 min
May 10, 10:26 PM CDTTornado WarningSHVSmith, Wood49 min
May 10, 10:27 PM CDTSevere Thunderstorm WarningLZKYell33 min
May 10, 10:35 PM CDTSevere Thunderstorm WarningLZKMontgomery, Polk, Scott40 min
May 10, 10:43 PM CDTTornado WarningSHVHempstead, Howard, Little River, Sevier32 min
May 10, 10:52 PM CDTSevere Thunderstorm WarningSHVCass, Harrison, Marion38 min
May 10, 10:59 PM CDTTornado WarningSHVHarrison, Marion46 min
May 10, 11:10 PM CDTSevere Thunderstorm WarningLZKLogan, Montgomery, Polk, Scott, Yell50 min
May 10, 11:13 PM CDTTornado WarningSHVHempstead, Howard32 min
May 10, 11:14 PM CDTSevere Thunderstorm WarningSHVCamp, Smith, Upshur, Wood61 min
May 10, 11:22 PM CDTTornado WarningSHVMiller38 min
May 10, 11:38 PM CDTTornado WarningSHVBowie, Red River, Titus37 min
May 10, 11:39 PM CDTFlash Flood WarningSHVSmith, Upshur, Wood4 hr
May 10, 11:46 PM CDTSevere Thunderstorm WarningSHVHempstead, Howard, Little River, Miller, Sevier44 min
May 10, 11:58 PM CDTTornado WarningSHVMiller36 min
May 10, 11:59 PM CDTFlash Flood WarningLZKJohnson, Logan, Montgomery, Newton, Polk, Pope and 3 more3 hr

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Shreveport, LA (KBAD), launched 00:00Z, 0.6 hours before the alert went out and 158 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 2015-05-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 482 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Shreveport, LA at 00:00Z on 2015-05-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 79 square meters per square second.19395878Sfc1 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
482 J/kg
Mixed-layer CIN
-35 J/kg
Mixed-layer LCL
1448 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
79 m²/s²
0-3 km storm-relative helicity
72 m²/s²
Significant tornado parameter
0.1
Supercell composite
5.7

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

318 
WWUS20 KWNS 110031
SEL1  
SPC WW 110031
ARZ000-OKZ000-TXZ000-110500-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 161
NWS STORM PREDICTION CENTER NORMAN OK
735 PM CDT SUN MAY 10 2015

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* TORNADO WATCH FOR PORTIONS OF 
  SOUTHWEST INTO CENTRAL ARKANSAS
  SOUTHEAST OKLAHOMA
  NORTHEAST TEXAS

* EFFECTIVE THIS SUNDAY NIGHT FROM 735 PM UNTIL MIDNIGHT CDT.

* PRIMARY THREATS INCLUDE...
  A COUPLE TORNADOES POSSIBLE
  ISOLATED VERY LARGE HAIL EVENTS TO 2 INCHES IN DIAMETER POSSIBLE
  ISOLATED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

SUMMARY...SEVERE THUNDERSTORMS ONGOING OVER NORTH-CENTRAL TEXAS AND
SOUTHEAST OKLAHOMA ARE EXPECTED TO SPREAD NORTHEAST ACROSS THE WATCH
AREA THIS EVENING.  SUPERCELLS CAPABLE OF A COUPLE OF
TORNADOES...LARGE HAIL AND DAMAGING STRAIGHT LINE WINDS ARE
POSSIBLE.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 65 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 80 MILES WEST SOUTHWEST OF
TEXARKANA ARKANSAS TO 25 MILES EAST NORTHEAST OF HOT SPRINGS
ARKANSAS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU1).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 155...WW 157...WW
159...WW 160...

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 22025.


...MEAD

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 10, 7:08 PM CDTMesoscale DiscussionSPCClark, Columbia, Dallas, Faulkner, Garland, Grant and 18 more97 min
May 10, 8:06 PM CDTMesoscale DiscussionSPCSebastian54 min
May 10, 9:57 PM CDTMesoscale DiscussionSPCClark, Columbia, Garland, Hempstead, Hot Spring, Howard and 12 more93 min
May 10, 11:31 PM CDTTornado WatchSPCArkansas, Bradley, Calhoun, Clark, Cleburne, Cleveland and 33 more5 hr
May 11, 2:31 AM CDTMesoscale DiscussionSPCEdwards, Kerr, Kimble, Real, Sutton, Val Verde89 min
May 11, 2:55 AM CDTMesoscale DiscussionSPCAngelina, Brazos, Burleson, Houston, Leon, Madison and 7 more95 min
May 11, 4:19 AM CDTSevere Thunderstorm WatchSPCBandera, Bastrop, Bexar, Blanco, Burnet, Caldwell and 18 more7 hr
May 11, 7:04 AM CDTMesoscale DiscussionSPCAustin, Bandera, Bastrop, Bexar, Blanco, Burleson and 34 more56 min
May 11, 2:16 PM CDTMesoscale DiscussionSPCAtascosa, Bee, Bexar, Colorado, DeWitt, Dimmit and 18 more119 min

Nearby

Tornado Watches in Arkansas, 2015Tornado Watches in Texas, 2015Tornado Watches in Oklahoma, 2015Every tornado watch in 2015

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.