Alert archive / Kansas / Tornado Watches in 2003

Tornado Watch 126

April 18, 20034 states

The Storm Prediction Center issued this tornado watch at Apr 18, 2003, 3:50 PM CDT for 4 states. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued: Apr 18, 2003, 3:50 PM CDT (20:50 UTC)
Expired: Apr 18, 2003, 10:00 PM CDT
In force: 6 hr
Issued by: the Storm Prediction Center

All 60 counties

Fremont County, IA, Mills County, IA, Anderson County, KS, Atchison County, KS, Brown County, KS, Chase County, KS, Clay County, KS, Cloud County, KS, Coffey County, KS, Dickinson County, KS, Doniphan County, KS, Douglas County, KS, Franklin County, KS, Geary County, KS, Jackson County, KS, Jefferson County, KS, Johnson County, KS, Leavenworth County, KS, Linn County, KS, Lyon County, KS, Marion County, KS, Marshall County, KS, McPherson County, KS, Miami County, KS, Morris County, KS, Nemaha County, KS, Osage County, KS, Ottawa County, KS, Pottawatomie County, KS, Republic County, KS, Riley County, KS, Saline County, KS, Shawnee County, KS, Wabaunsee County, KS, Washington County, KS, Atchison County, MO, Holt County, MO, Butler County, NE, Cass County, NE, Clay County, NE, Fillmore County, NE, Gage County, NE, Hamilton County, NE, Howard County, NE, Jefferson County, NE, Johnson County, NE, Lancaster County, NE, Merrick County, NE, Nemaha County, NE, Nuckolls County, NE, Otoe County, NE, Pawnee County, NE, Polk County, NE, Richardson County, NE, Saline County, NE, Sarpy County, NE, Saunders County, NE, Seward County, NE, Thayer County, NE, York County, NE

The radar

The Topeka radar (KTWX), 109 km from the middle of the area, began a volume at 20:52 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.

Discussions around it

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

The nearest sounding before it

Topeka, KS (KTOP), launched 12:00Z, 8.8 hours before the alert went out and 122 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 839 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 182 m²/s²
0-3 km storm-relative helicity: 318 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.

000 
WWUS20 KWNS 182053
SEL6  
SPC WW 182050
IAZ000-KSZ000-MOZ000-NEZ000-190300-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 126
STORM PREDICTION CENTER NORMAN OK
350 PM CDT FRI APR 18 2003

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

EXTREME SOUTHWEST IOWA                               
NORTHEAST KANSAS                             
EXTREME NORTHWEST MISSOURI                           
SOUTHEAST NEBRASKA                           

EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 350 PM UNTIL 1000
PM CDT.

TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 85 STATUTE MILES EAST AND WEST
OF A LINE FROM 30 MILES NORTH NORTHWEST OF LINCOLN NEBRASKA TO 20
MILES SOUTH SOUTHEAST OF EMPORIA KANSAS.

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.


DISCUSSION...RAPID DESTABILIZATION EXPECTED TO CONTINUE OVER NE
KS/SE NEB...WITH SURFACE-BASED CAPE OF 1000-2000 J/KG EXPECTED IN
THE NEXT 2-4 HOURS OVER MOST OF NE KS AND SE NEB.  EXPECT
THUNDERSTORMS TO DEVELOP BY 22-23Z NEAR THE SYNOPTIC TRIPLE POINT
IN S CENTRAL NEB...AND NEAR A SECONDARY INTERSECTION OF A
CONFLUENCE AXIS AND THE WARM FRONT IN NE KS.  VERTICAL SHEAR
REMAINS STRONG OVER THIS AREA...AND THE COMBINATION OF SHEAR/
INSTABILITY WILL SUPPORT SUPERCELLS WITH LARGE HAIL AND DAMAGING
WINDS.  ADDITIONALLY...LOW-LEVEL MOISTURE/SHEAR WILL BECOME
SUFFICIENT FOR A TORNADO THREAT ACROSS NE KS/SE NEB THIS EVENING.


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 24035.


...THOMPSON

411,0952 380,0942 380,0973 411,0983

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 18, 5:15 PM CDT	Mesoscale Discussion	SPC	Fremont	90 min
Apr 18, 6:20 PM CDT	Severe Thunderstorm Watch	SPC	Crawford, Harrison, Ida, Monona, Pottawattamie, Sac and 2 more	6 hr
Apr 18, 6:14 AM CDT	Mesoscale Discussion	SPC	Clay, Cloud, Dickinson, Ellsworth, Geary, Harvey and 13 more	2 hr
Apr 18, 2:52 PM CDT	Mesoscale Discussion	SPC	Atchison, Brown, Clay, Cloud, Coffey, Douglas and 15 more	113 min

Nearby

Tornado Watches in Kansas, 2003 Tornado Watches in Nebraska, 2003 Tornado Watches in Iowa, 2003 Every tornado watch in 2003

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.