Alert archive / Iowa / Flash Flood Warnings in 1990

Flash Flood Warning 5, NWS Sioux Falls, SD

June 16, 1990Lyon County, Sioux County, Iowa

NWS Sioux Falls, SD issued this flash flood warning at Jun 16, 1990, 7:39 PM CDT for Lyon County, Sioux County, Iowa. It was in force for 4 hr.

The area

The counties it named.

The facts

Issued
Jun 16, 1990, 7:39 PM CDT (00:39 UTC)
Expired
Jun 16, 1990, 11:45 PM CDT
In force
4 hr
Issued by
NWS Sioux Falls, SD
Area
Whole counties

Counties Lyon County, IA, Sioux County, IA

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

Aberdeen, SD (KHON), launched 00:00Z, 0.7 hours before the alert went out and 256 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, Aberdeen, SD at 00:00Z on 1990-06-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Aberdeen, SD at 00:00Z on 1990-06-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 40 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
908 m above ground
0-6 km bulk shear
61 kt
0-1 km storm-relative helicity
40 m²/s²
0-3 km storm-relative helicity
224 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KFSD 170040
FFWFSD
IAC119-167-170445-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
739 PM CDT  JUN 16 1990
 
THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL 1145 PM CDT
FOR PEOPLE IN THE FOLLOWING COUNTIES...
 
IN NORTHWEST IOWA
          ...LYON...SIOUX
 
SOME CITIES INCLUDED IN THIS WARNING...SIOUX CENTER...ROCK
VALLEY...ROCK RAPIDS.
 
AT 735 PM RADAR INDICATED A LARGE AREA OF HEAVY RAINS OVER SIOUX AND
LYON COUNTIES OF NORTHWEST IOWA. RAINFALL AMOUNTS OF 2.5 TO 3.5 INCHES
HAVE ALREADY FALLEN IN THE ROCK VALLEY AREA. CREEKS WERE ALREADY OVER
FLOWING IN THE ROCK VALLEY AREA. ROCK VALLEY IS LOCATED ABOUT 25 MILES
SOUTHEAST OF SIOUX FALLS SOUTH DAKOTA.
 
A FLASH FLOOD WARNING MEANS FLASH FLOODING IS OCCURING OR IS
IMMINENT. ACT QUICKLY TO SAVE YOURSELF. GET OUT OF LOWLAND AREAS
SUBJECT TO FLOODING. AVOID ALREADY FLOODED AREAS. CAMPERS ALONG
STREAMS AND SMALL RIVERS SHOULD MOVE TO HIGHER GROUND.
 
DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY.  THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO
CROSS SAFELY.  VEHICLES CAUGHT IN RISING WATER SHOULD BE
ABANDONED QUICK\LY.  MOVE TO HIGHER GROUND.

What forecasters said that day

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

In the hours before

Special weather statement, Jun 16, 5:45 PM CDT, 1 hour 54 minutes before
IAZ004-162330-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX CITY IA
544 PM CDT SAT JUN 16 1990

...A FLASH FLOOD WATCH IS IN EFFECT FOR NORTHEAST NEBRASKA AND
   NORTHWEST IOWA TONIGHT...
...A TORNADO WATCH IS IN EFFECT FOR NORTHEAST NEBRASKA AND SOUTHEAST
   SOUTH DAKOTA UNTIL 9 PM CDT...

A STRONG THUNDERSTORM WAS MOVING INTO NORTHERN UNION COUNTY SOUTH
DAKOTA LATE THIS AFTERNOON. AT 5:43 PM CDT RADAR SHOWED A THUNDERSTORM
ENTERING NORTHWEST UNION COUNTY. THE STORM WAS MOVING NORTHEAST AT
20 MPH.

THE STORM WILL PRODUCE LOCALLY HEAVY RANFALL AND MAY PRODUCE PEA TO
MARBLE SIZE HAIL. PEOPLE IN NORTHERN UNION COUNTY SHOULD BE ALERT
TO CHANGING WEATHER CONDITIONS AND BE PREPARE~D TO MOVE TO A PLACE OF
SAFETY IF THREATENING WEATHER APPROACHES.
HOPPES
Special weather statement, Jun 16, 6:16 PM CDT, 1 hour 23 minutes before
SDZ017-018-019-020-162300-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
615 PM CDT SAT JUN 16 1990

...TORNADO WATCH IN EFFECT FOR SOUTHCENTRAL AND SOUTHEAST SOUTH
DAKOTA UNTIL 7PM CDT...

AT 605 PM CDT SCATTERED THUNDERSTORMS WITH VERY HEAVY RAIN CONTINUED
IN SOUTHEAST SOUTH DAKOTA.

THE THUNDERSTORMS WERE LOCATED SOUTH OF A LINE FROM SIOUX FALLS TO
MITCHELL SOUTH DAKOTA.

STRONGER THUNDERSTORMS WERE LOCATED 30 MILES SOUTH OF SIOUX FALLS
OR JUST NORTHEAST OF BERESFORD AND JUST NORTH OF YANKTON.

THESE STORMS ARE CAPABLE OF DANGEROUS CLOUD TO GROUND LIGHTNING...
HAIL AND GUSTY WINDS.
<
THESE STORMS CAN PRODUCE A TORNADO WITH LITTLE OR NO ADVANCE
WARNING SO BE ON NTHE LOOKOUT AND LISTEN TO LATER STATEMENTS AND
WARNINGS.

MOVEMENT OF THE STORMS WAS NORTHEAST AT 35 MILES AN HOUR.
 SHEEHAN
Special weather statement, Jun 16, 6:53 PM CDT, 46 minutes before
SDZ012-018-170015-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
652 PM CDT SAT JUN 16 1990

...LINE OF THUNDERSTORMS MOVING ACROSS BROOKINGS AND LAKE COUNTIES
OF EASTERN SOUTH DAKOTA...

AT 650 PM CDT RADAR INDICATED A LINE OF THUNDERSTORMS WITH HEAVY RAINS
FROM 50 MILES NORTH NORTHWEST OF SIOUX FALLS NEAR BROOKINGS TO 35 MILES
NORTHWEST OF SIOUX FALLS JUST SOUTHWEST OF MADISON SOUTH DAKOTA.
THIS LINE WAS MOVING EAST AT 45 MPH.

GUSTY WINDS...SMALL HAIL AND HEAVY RAINS CAN BE EXPECTED WITH THIS LINE
AS IT MOVES EAST ACROSS LAKE AND BROOKINGS COUNTY.
Special weather statement, Jun 16, 7:17 PM CDT, 22 minutes before
SDZ012-017-018-019-020-170100-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
717 PM CDT SAT JUN 16 1990

...TORNADO WATCH IN EFFECT FOR SOUTHCENTRAL AND SOUTHEAST SOUTH
DAKOTA UNTIL 7PM CDT...

AT 705 PM CDT SCATTERED THUNDERSTORMS WITH VERY HEAVY RAIN CONTINUED
IN SOUTHEAST SOUTH DAKOTA AND NORTHWEST IOWA.

THE THUNDERSTORMS EXTENDED FROM NEAR YANKTON TO NEAR BROOKINGS.

STRONGER THUNDERSTORMS WERE LOCATED NEAR BROOKINGS AND 25 MILES SOUTH/
EAST OF SIOUX FALLS NEAR SIOUX CENTER IOWA.

THESE STORMS ARE CAPABLE OF DANGEROUS CLOUD TO GROUND LIGHTNING...
HAIL AND GUSTY WINDS.
THESE STORMS CAN PRODUCE A TORNADO WITH LITTLE OR NO ADVANCE
WARNING SO BE ON THE LOOKOUT AND  LISTEN TO LATER STATEMENTS AND
WARNINGS.

MOVEMENT WAS NORTHEAST AT 35 MILES AN HOUR.
 BERG
Special weather statement, Jun 16, 7:22 PM CDT, 17 minutes before
SDZ012-017-018-019-020-170100-

SPECIAL WEATHER STATEMENT   ...CORRECTED FOR TORNADO WATCH...
NATIONAL WEATHER SERVICE SIOUX FALLS SD
722 PM CDT SAT JUN 16 1990

...TORNADO WATCH IN EFFECT FOR EAST CENTRAL AND SOUTHEAST SOUTH
DAKOTA...SOUTHWEST MINNESOTA AND NORTHWEST IOWA UNTIL 11 PM CDT...

AT 705 PM CDT SCATTERED THUNDERSTORMS WITH VERY HEAVY RAIN CONTINUED
IN SOUTHEAST SOUTH DAKOTA AND NORTHWEST IOWA.

THE THUNDERSTORMS EXTENDED FROM NEAR YANKTON TO NEAR BROOKINGS.

STRONGER THUNDERSTORMS WERE LOCATED NEAR BROOKINGS AND 25 MILES SOUTH/
EAST OF SIOUX FALLS NEAR SIOUX CENTER IOWA.

THESE STORMS ARE CAPABLE OF PRODUCING DANGEROUS CLOUD TO GROUND
LIGHTENING...HAIL AND GUSTY WINDS.
TH1ESE STORMS CAN PRODUCE A TORNADO WITH LITTLE OR NO ADVANCE
WARNING SO BE ON THE LOOKOUT AND LISTEN TO LATER STATEMENTS AND
WARNINGS.

MOVEMENT WAS NORTHEAST AT 35 MILES AN HOUR.
 BERG
Special weather statement, Jun 16, 7:25 PM CDT, 14 minutes before
IAZ004-170130-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX CITY IA
725 PM CDT SAT JUN 16 1990

...A FLASH FLOOD WATCH IS IN EFFECT FOR NORTHEAST NEBRASKA AND
   NORTHWEST IOWA TONIGHT...
...A TORNADO WATCH IS IN EFFECT FOR NORTHEAST NEBRASKA UNTIL 9 PM CDT.
...A TORNADO WATCH IS IN EFFECT FOR SOUTHEAST SOUTH DAKOTA AND PART
   OF NORTHWEST IOWA UNTIL 11 PM CDT...

STRONG THUNDERSTORMS WERE MOVING ACROSS SIOUX COUNTY IOWA EARLY THIS
EVENING. AT 7:20 PM CDT RADAR SHOWED THUNDERSTORMS NORTH OF A LINE
FROM CHATSWORTH IOWA TO HOSPERS IOWA. THE STORMS WERE MOVING
NORTHEAST AT 35 MPH.

THE STORM WILL PRODUCE LOCALLY HEAVY RANFALL AND MAY PRODUCE PEA TO
MARBLE SIZE HAIL. PEOPLE IN SIOUX COUNTY SHOULD BE ALERT TO CHANGING
WEATHER CONDITIONS AND BE PREPARED TO MOVE TO A PLACE OF SAFETY IF
THREATENING WEATHER APPROACHES.

HOPPES

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 16, 7:32 PM CDTSevere Thunderstorm WarningFSDSioux28 min
Jun 16, 8:03 PM CDTSevere Thunderstorm WarningFSDOsceola27 min
Jun 16, 8:26 PM CDTSevere Thunderstorm WarningFSDMonona, Woodbury64 min
Jun 16, 9:08 PM CDTSevere Thunderstorm WarningFSDCherokee, Ida37 min

Nearby

Flash Flood Warnings in Iowa, 1990Every flash flood warning in 1990

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.