Alert archive / Missouri / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 159, NWS St. Louis, MO

June 11, 1999Callaway County, Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Jun 11, 1999, 2:51 PM CDT for Callaway County, Missouri. It was in force for 49 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jun 11, 1999, 2:51 PM CDT (19:51 UTC)
Expired: Jun 11, 1999, 3:40 PM CDT
In force: 49 min
Issued by: NWS St. Louis, MO
Area: Whole counties

County Callaway County, MO

The radar

The St Louis radar (KLSX), 109 km from the middle of the area, began a volume at 19:53 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.

The nearest sounding before it

Springfield, MO (KSGF), launched 12:00Z, 7.9 hours before the alert went out and 271 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: 309 J/kg
Mixed-layer CIN: -58 J/kg
Mixed-layer LCL: 959 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 56 m²/s²
0-3 km storm-relative helicity: 71 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.6

Open this sounding in Storm Lab

The text

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

825 
WUUS1 KSTL 111950 RRA
SVRSTL
MOC027-112040-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
251 PM CDT FRI JUN 11 1999

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CALLAWAY COUNTY IN CENTRAL MISSOURI

* UNTIL 340 PM CDT

* AT 251 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 3 MILES SOUTH OF FULTON... MOVING NORTH AT 20
  MPH.

* LOCATIONS THAT WILL BE AFFECTED...
  FULTON
  KINGDOM CITY
  AUXVASSE



SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND GUSTS IN EXCESS OF 60
MPH...DAMAGING HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN. MOVE
TO AN INTERIOR ROOM ON THE LOWEST FLOOR OR YOUR HOME OR BUSINESS.
HEAVY RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE INTO AREAS WHERE
WATER COVERS THE ROAD.



FG/RP

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS St. Louis, MO wrote its last area forecast discussion before this severe thunderstorm warning went out at Jun 11, 3:37 AM CDT, 11 hours 14 minutes earlier.

Area forecast discussion, Jun 11, 3:37 AM CDT, 11 hours 14 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
337 AM CDT FRI JUN 11 1999

THE LATEST SFC ANALYSIS INDICATES A SFC LOW LOCATED OVR IOWA WITH A
COLD FRONT EXTENDING ACROSS KANSAS. I AGREE WITH THE SPC DAY 1
OUTLOOK OF PLACING THE MAIN THREATS OF SVR WEATHER AHEAD OF THE
DRYLINE..NEAR THE 850 THETA E RIDGE OVR WEST TEXAS AND WRN
KANSAS...AND NEAR THE SFC LOW LOCATED IN IOWA.

FOR OUR FORECAST AREA...DETERMINING WHERE THUNDERSTORMS WILL
FORM WILL NOT BE AS CLEAR CUT AS IN THOSE AREAS.  THIS PRESENTS THE
FORECAST PROBLEM OF THE DAY.  CAPES OF 500-1500 J/KG ACROSS THE AREA
LATER TODAY AND ABUNDANT LOW LVL MSTR WILL ALLOW SCATTERED
SHOWERS AND THUNDERSTORMS TO DEVELOP ALONG BOUNDARIES FROM PREVIOUS
CONVECTION...AS WELL AS NEAR THERMAL BOUNDARIES SET UP BY
DIFFERENTIAL HEATING CAUSED BY VARYING AMOUNTS OF CLOUD COVER.  200
MB COUPLED JETS SOUTHWEST OF OUR FORECAST AREA OVER OKLAHOMA COULD
PROVIDE SUFFICIENT UPPER SUPPORT TO AID IN SCATTERED CONVECTION OVR
AREAS SOUTHWEST OF OUR FORECAST. WITH SOUTHWEST UPPER FLOW...SOME OF
THESE THUNDERSTORMS COULD ALSO MOVE INTO OUR AREA.  THE WEAK WIND
FIELD WILL SUPPORT SLOWER MOVING STORMS. THUS...SOME LOCATIONS
ACROSS THE FORECAST AREA COULD RECEIVE HEAVY RAIN AND LOCALIZED
FLOODING WITH STRONGER STORMS THAT DEVELOP LATER THIS AFTERNOON.

AS THE COLD FRONT APPROACHES OUR AREA THIS WEEKEND...MORE ORGANIZED
DEVELOPMENT OF SHOWERS AND THUNDERSTORMS IS EXPECTED...THUS I AGREE
WITH THE INCREASING POPS INDICATED IN BOTH THE FWC AND FAN GUIDANCE.
MY PREFERRED MODEL WAS THE ETA.

(PRELIMINARY CCF FOR COORDINATION PURPOSES ONLY)

CCF
SGF EE 083/065 080/062 081 103444
JLN EE 083/065 080/063 082 103444
UNO BE 088/070 08T5/066 085 103333
VIH BE 086/068 082/064 083 103344

VESPER

The office that day

Everything else NWS St. Louis, MO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 11, 11:21 AM CDT	Severe Thunderstorm Warning	LSX	Saint Charles, Saint Louis	49 min
Jun 11, 1:30 PM CDT	Severe Thunderstorm Warning	LSX	Callaway, Montgomery	50 min
Jun 11, 3:32 PM CDT	Severe Thunderstorm Warning	LSX	Warren	48 min
Jun 11, 5:23 PM CDT	Severe Thunderstorm Warning	LSX	Saint Charles, Saint Louis	47 min

Nearby

Severe Thunderstorm Warnings in Missouri, 1999 Every severe thunderstorm warning in 1999

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.