Alert archive / Tennessee / Severe Thunderstorm Watches in 2001

Severe Thunderstorm Watch 577

July 18, 20014 states

The Storm Prediction Center issued this severe thunderstorm watch at Jul 18, 2001, 4:45 PM CDT for 4 states. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued: Jul 18, 2001, 4:45 PM CDT (21:45 UTC)
Expired: Jul 18, 2001, 10:00 PM CDT
In force: 5 hr
Issued by: the Storm Prediction Center

All 64 counties

Clay County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Fulton County, AR, Greene County, AR, Independence County, AR, Jackson County, AR, Lawrence County, AR, Mississippi County, AR, Poinsett County, AR, Randolph County, AR, Sharp County, AR, White County, AR, Woodruff County, AR, Calloway County, KY, Carlisle County, KY, Fulton County, KY, Graves County, KY, Hickman County, KY, Todd County, KY, Trigg County, KY, Butler County, MO, Dunklin County, MO, Mississippi County, MO, New Madrid County, MO, Oregon County, MO, Pemiscot County, MO, Ripley County, MO, Stoddard County, MO, Benton County, TN, Carroll County, TN, Cheatham County, TN, Chester County, TN, Crockett County, TN, Decatur County, TN, Dickson County, TN, Dyer County, TN, Fayette County, TN, Gibson County, TN, Giles County, TN, Hardeman County, TN, Hardin County, TN, Haywood County, TN, Henderson County, TN, Henry County, TN, Hickman County, TN, Houston County, TN, Humphreys County, TN, Lake County, TN, Lauderdale County, TN, Lawrence County, TN, Lewis County, TN, Madison County, TN, Maury County, TN, McNairy County, TN, Montgomery County, TN, Obion County, TN, Perry County, TN, Shelby County, TN, Stewart County, TN, Tipton County, TN, Wayne County, TN, Weakley County, TN

The radar

The Paducah radar (KPAH), 104 km from the middle of the area, began a volume at 21:46 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.

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
Jul 18, 5:24 PM CDT	Severe Thunderstorm Warning	OHX	Houston, Montgomery, Stewart	36 min
Jul 18, 5:39 PM CDT	Severe Thunderstorm Warning	PAH	Fulton	21 min
Jul 18, 5:46 PM CDT	Severe Thunderstorm Warning	OHX	Dickson, Montgomery	29 min
Jul 18, 7:08 PM CDT	Severe Thunderstorm Warning	MEG	Randolph	37 min
Jul 18, 7:32 PM CDT	Severe Thunderstorm Warning	PAH	Ripley	43 min
Jul 18, 8:04 PM CDT	Severe Thunderstorm Warning	LZK	Sharp	56 min

The nearest sounding before it

Little Rock, AR (KLZK), launched 12:00Z, 9.8 hours before the alert went out and 174 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1412 J/kg
Mixed-layer CIN: -132 J/kg
Mixed-layer LCL: 929 m above ground
0-6 km bulk shear: 17 kt
0-1 km storm-relative helicity: 67 m²/s²
0-3 km storm-relative helicity: 134 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

458 
WWUS9 KMKC 182138
SEL7  
MKC WW 182131
ARZ000-MOZ000-TNZ000-190300-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 577
STORM PREDICTION CENTER NORMAN OK
431 PM CDT WED JUL 18 2001

THE STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

   NORTHEAST ARKANSAS                           
   SOUTHEAST MISSOURI                           
   WEST AND MIDDLE TENNESSEE                          

EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 445 PM UNTIL
1000 PM CDT.

HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 135 STATUTE MILES
EAST AND WEST OF A LINE FROM 60 MILES NORTH OF DYERSBURG TENNESSEE
TO 35 MILES EAST OF MEMPHIS TENNESSEE.

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR 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.  SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE
TORNADOES.

OTHER WATCH INFORMATION...  CONTINUE...WW 574...WW 575...WW 576...

DISCUSSION...SRN IL MCS EXPECTED TO CONTINUE GENERALLY SSEWD THIS
EVENING...WITH CELL PROPAGATION AUGMENTING SYSTEM MAINLY ON ITS W
END WITH TIME.  COMBINATION OF VERY WARM/MOIST WLY BOUNDARY LAYER
FLOW AHEAD OF MCS...AND MODEST N TO NW WINDS AT MID LEVELS...
SUGGEST CONTINUED LIKELIHOOD FOR A FEW WET MICROBURSTS AND POSSIBLY
HAIL.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 1 INCH EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS. 
A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550.  MEAN STORM MOTION
VECTOR 35025.

...CORFIDI

365,0865 350,0865 350,0914 365,0915

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 18, 1:15 PM CDT	Severe Thunderstorm Watch	SPC	Ballard, Caldwell, Carlisle, Christian, Crittenden, Graves and 10 more	5 hr
Jul 18, 1:00 AM CDT	Severe Thunderstorm Watch	SPC	Andrew, Buchanan, Caldwell, Clinton, Daviess, DeKalb and 9 more	4 hr

Nearby

Severe Thunderstorm Watches in Tennessee, 2001 Severe Thunderstorm Watches in Arkansas, 2001 Severe Thunderstorm Watches in Missouri, 2001 Every severe thunderstorm watch in 2001

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.