Alert archive / Missouri / Flash Flood Warnings in 1998

Flash Flood Warning 1, NWS St. Louis, MO

May 21, 1998Iron County, Madison County, Missouri

NWS St. Louis, MO issued this flash flood warning at May 21, 1998, 6:30 PM CDT for Iron County, Madison County, Missouri. It was in force for 5 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: May 21, 1998, 6:30 PM CDT (23:30 UTC)
Expired: May 21, 1998, 11:25 PM CDT
In force: 5 hr
Issued by: NWS St. Louis, MO
Area: Whole counties

Counties Iron County, MO, Madison County, MO

The radar

The St Louis radar (KLSX), 135 km from the middle of the area, began a volume at 23:32 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, 11.5 hours before the alert went out and 298 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: 2242 J/kg
Mixed-layer CIN: -143 J/kg
Mixed-layer LCL: 1149 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 55 m²/s²
0-3 km storm-relative helicity: 86 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 4.8

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KSTL 212330
FFWSTL
MOC093-123-220425-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
630 PM CDT THU MAY 21 1998

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  IRON COUNTY IN SOUTHEASTERN MISSOURI
  MADISON COUNTY MISSOURI IN SOUTHEASTERN MISSOURI

* UNTIL 1125 PM CDT

* AT 625 PM...NATIONAL WEATHER SERVVICE DOPPLER RADAR WAS DETECTING
  A LINE OF THUNDERSTORMS CONTAINING HEAVY RAIN EXTENDING FROM ROLLA
  TO FREDERICKTOWN.  THESE STORMS WERE MOVING TO THE EAST SOUTHEAST
  FOLLOWING ONE ANOTHER.  LOCALLY HEAVY RAIN FROM STORMS DURING THE
  AFTERNOON HAVE CREATED VERY SATURATED CONDITIONS OVER THIS AREA...
  AND ADDITIONAL RAIN OF 1 TO POSSIBLY 4 INCHES MAY OCCUR.

* NORTHERN PORTIONS OF BOTH OF THESE COUNTIES WILL BE MOST AT RISK
  FOR FLOODING OF LOW LYING AREAS AND CREEKS AND STREAMS DURING
  THE EVENING.  TOWNS WHICH MAY EXPERIENCE FLOODING PROBLEMS
  INCLUDE IRONTON...FREDERICKTOWN AND PILOT KNOB.

  BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
  DANGERS OF FLOODING. IT IS VERY DIFFICULT AT NIGHT TO TELL HOW
  DEEP THE WATER MAY BE. MOTORISTS SHOULD NEVER DRIVE THROUGH WATER
  OF :UNKNOWN DEPTH.

  GKS/DJP

The office that day

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

Issued	Product	Office	Counties	Lasted
May 21, 10:16 AM CDT	Severe Thunderstorm Warning	LSX	Shelby	49 min
May 21, 10:58 AM CDT	Severe Thunderstorm Warning	LSX	Audrain, Monroe	47 min
May 21, 11:29 AM CDT	Severe Thunderstorm Warning	LSX	Pike	46 min
May 21, 11:41 AM CDT	Severe Thunderstorm Warning	LSX	Callaway, Montgomery	44 min
May 21, 12:05 PM CDT	Severe Thunderstorm Warning	LSX	Callaway	35 min
May 21, 12:13 PM CDT	Severe Thunderstorm Warning	LSX	Osage	32 min
May 21, 12:25 PM CDT	Severe Thunderstorm Warning	LSX	Saint Charles, Warren	50 min
May 21, 12:28 PM CDT	Severe Thunderstorm Warning	LSX	Gasconade	47 min
May 21, 12:53 PM CDT	Severe Thunderstorm Warning	LSX	Saint Louis	47 min
May 21, 12:57 PM CDT	Severe Thunderstorm Warning	LSX	Franklin	48 min
May 21, 1:06 PM CDT	Severe Thunderstorm Warning	LSX	City of Saint Louis	44 min
May 21, 1:44 PM CDT	Severe Thunderstorm Warning	LSX	Jefferson	46 min
May 21, 1:54 PM CDT	Severe Thunderstorm Warning	LSX	Washington	46 min
May 21, 2:28 PM CDT	Severe Thunderstorm Warning	LSX	Iron, Madison, Saint Francois	52 min
May 21, 3:20 PM CDT	Severe Thunderstorm Warning	LSX	Iron, Madison	45 min

Nearby

Flash Flood Warnings in Missouri, 1998 Every flash flood warning in 1998

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.