Alert archive / Arkansas / Tornado Watches in 2008

Tornado Watch 883

September 2, 20087 counties in Arkansas; 6 counties in Mississippi; Shelby County, Tipton County, Tennessee

The Storm Prediction Center issued this tornado watch at Sep 2, 2008, 4:38 PM CDT for 7 counties in Arkansas; 6 counties in Mississippi; Shelby County, Tipton County, Tennessee. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
Sep 2, 2008, 4:38 PM CDT (21:38 UTC)
Expired
Sep 2, 2008, 7:27 PM CDT
In force
3 hr
Issued by
the Storm Prediction Center
Largest hail expected
0.5 in
Strongest gust expected
60 kt

Counties Craighead County, AR, Crittenden County, AR, Cross County, AR, Lee County, AR, Mississippi County, AR, Poinsett County, AR, St. Francis County, AR, DeSoto County, MS, Lafayette County, MS, Marshall County, MS, Panola County, MS, Tate County, MS, Tunica County, MS, Shelby County, TN, Tipton County, TN

The radar

The Memphis radar (KNQA), 54 km from the middle of the area, began a volume at 21:39 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
50%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
10%
One or more gusts of 65 knots or more
5%
Ten or more severe hail reports
5%
One or more hailstones of 2 inches or more
5%
Six or more combined severe hail and wind reports
30%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Sep 2, 4:38 PM CDTTornado WarningMEGTate22 min
Sep 2, 5:07 PM CDTTornado WarningMEGLafayette, Marshall, Tate23 min

Discussions around it

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

The nearest sounding before it

Little Rock, AR (KLZK), launched 12:00Z, 9.6 hours before the alert went out and 33 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, Little Rock, AR at 12:00Z on 2008-09-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 409 joules per kilogram.LCLEL10008507005003002001001 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, Little Rock, AR at 12:00Z on 2008-09-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 258 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
409 J/kg
Mixed-layer CIN
-1 J/kg
Mixed-layer LCL
483 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
258 m²/s²
0-3 km storm-relative helicity
226 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.3

Open this sounding in Storm Lab

The text

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

000
WWUS20 KWNS 022141
SEL3  
SPC WW 022141
ARZ000-MSZ000-TNZ000-030200-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 883
NWS STORM PREDICTION CENTER NORMAN OK
440 PM CDT TUE SEP 2 2008

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF 

       EASTERN ARKANSAS
       NORTHWESTERN MISSISSIPPI
       EXTREME SOUTHWESTERN TENNESSEE

EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 440 PM UNTIL
900 PM CDT.

TORNADOES...HAIL TO 0.5 INCH IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 30 STATUTE
MILES EITHER SIDE OF A LINE FROM 55 MILES NORTHWEST OF MEMPHIS
TENNESSEE TO 15 MILES SOUTH SOUTHEAST OF OXFORD MISSISSIPPI.  FOR
A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU3).

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 882...

DISCUSSION...SMALL BAND OF ROTATING STORMS HAD DEVELOPED ALONG AN
OUTER BAND THAT WAS LOCATED WITHIN AN AREA OF SURFACE TEMPERATURES
IN THE LOWER TO MID 80S. THIS ADDED INSTABILITY AND 1 KM SHEAR
AROUND 30 KT WILL LIKELY CONTINUE A THREAT FOR ROTATING STORMS AND A
FEW TORNADOES AS THE STORMS SHIFT NNWWD. THE TORNADO THREAT SHOULD
DIMINISH BETWEEN 00-02Z WITH LOSS OF DAYTIME HEATING.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 15030.


...IMY

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 1, 11:01 PM CDTMesoscale DiscussionSPCAshley, Chicot59 min
Sep 2, 6:42 PM CDTMesoscale DiscussionSPCBaxter, Boone, Carroll, Craighead, Crittenden, Cross and 10 more2 hr
Sep 1, 11:41 PM CDTTornado WatchSPCAdams, Amite, Claiborne, Copiah, Covington, Forrest and 25 more7 hr
Sep 2, 3:42 AM CDTMesoscale DiscussionSPCAmite, Claiborne, Copiah, Covington, Forrest, Franklin and 26 more93 min
Sep 2, 6:04 AM CDTMesoscale DiscussionSPCAmite, Attala, Claiborne, Copiah, Covington, Forrest and 25 more56 min
Sep 2, 6:34 AM CDTTornado WatchSPCAdams, Amite, Attala, Bolivar, Carroll, Claiborne and 46 more9 hr
Sep 2, 3:11 PM CDTMesoscale DiscussionSPCAdams, Amite, Attala, Bolivar, Carroll, Claiborne and 46 more64 min
Sep 2, 3:54 PM CDTTornado WatchSPCAdams, Amite, Claiborne, Copiah, Covington, Franklin and 22 more6 hr

Nearby

Tornado Watches in Arkansas, 2008Tornado Watches in Mississippi, 2008Tornado Watches in Tennessee, 2008Every tornado watch in 2008

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.