Alert archive / Nebraska / Flash Flood Warnings in 1997

Flash Flood Warning 5, NWS Omaha, NE

July 7, 1997Colfax County, Dodge County, Nebraska

NWS Omaha, NE issued this flash flood warning at Jul 7, 1997, 8:59 PM CDT for Colfax County, Dodge County, Nebraska. It was in force for 6 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
Jul 7, 1997, 8:59 PM CDT (01:59 UTC)
Expired
Jul 8, 1997, 2:55 AM CDT
In force
6 hr
Issued by
NWS Omaha, NE
Area
Whole counties

Counties Colfax County, NE, Dodge County, NE

The radar

The Omaha radar (KOAX), 51 km from the middle of the area, began a volume at 02:00 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

Omaha, NE (KOAX), launched 00:00Z, 2.0 hours before the alert went out and 50 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, Omaha, NE at 00:00Z on 1997-07-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1901 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Omaha, NE at 00:00Z on 1997-07-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 154 square meters per square second.193958Sfc1 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
1901 J/kg
Mixed-layer CIN
-10 J/kg
Mixed-layer LCL
1492 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
154 m²/s²
0-3 km storm-relative helicity
328 m²/s²
Significant tornado parameter
1.0
Supercell composite
13.4

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KOMA 080159
FFWOMA
NEC037-053-080755-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
859 PM CDT MON JUL 7 1997

* FLASH FLOOD WARNING FOR
  COLFAX COUNTY - IN NORTHEASTERN NEBRASKA
  DODGE COUNTY - IN EAST CENTRAL NEBRASKA

* UNTIL 255 AM CDT
 
* SOME STREAMS AFFECTED
  MAPLE CREEK

* CAUSE AND EFFECT
RADAR ESTIMATES INDICATE THAN MORE THAN TWO INCHES OF RAIN HAVE
FALLE N IN NORTHERN AND NORTHWEST DODGE COUNTY AND THUNDERSTORMS
CONTINUE TO MOVE THROUGH THE AREA.  2 INCHES OF RAIN FELL IN A
SHORT TIME AT  CLARKSON IN NORTHERN COLFAX COUNTY.

FLOODING OF SMALL STREAMS AND ROADS IS LIKELY.  IN ADDITION THE
RAINFALL SHOULD BE SUFFICIENT TO BRING MAPLE CREEK TO BANKFULL WITH
SOME MINOR OVERFLOWS LIKELY WHERE DEBREE OR OTHER BLOCKAGE IS
OCCURRING.
 
DO NOT DRIVE THROUGH FLOODED AREAS. SHALLOW...SWIFTLY FLOWING WATER
CAN WASH A CAR FROM A ROADWAY.  ALSO...THE ROADBED MAY NOT BE
INTACT UNDER THE WATER.

FURTHER HEAVY RAINFALL MAY CONTRIBUTE TO FURTHER RISES IN DODGE
COUNTY. SOME LIGHTER RAINFALL IS LIKELY IN NORTHERN COLFAX COUNTY
ALTHOUGH HEAVIER RAIN MAY OCCUR BEFORE 11 PM IN SOUTHERN COLFAX
COUNTY.

POWERS

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, Jul 7, 7:55 PM CDT, 1 hour 4 minutes before
NEZ011-012-016>018-080300-

SPECIAL WEATHER STATEMENT CLEARING PART OF TORNADO WATCH 580
NATIONAL WEATHER SERVICE OMAHA NE
755 PM CDT MON JUL 7 1997

...TORNADO WATCH CANCELLED FOR COUNTIES IN NORTHEAST NEBRASKA TO THE
NORTH OF NORFOLK...

TORNADO WATCH NUMBER 580...ISSUED ABOUT 315 PM THIS MONDAY EVENING IS
NO LONGER IN EFFECT FOR KNOX...CEDAR...ANTELOPE...PIERCE AND WAYNE
COUNTIES OF NORTHEAST NEBRASKA.

THE SQUALL LINE AND COLD FRONT GENERATING SEVERE WEATHER HAS PASSED TO
THE SOUTHEAST OF THESE COUNTIES.

TORNADO WATCH 680 REMAINS IN EFFECT FOR THE COUNTIES OF NORTHEAST
NEBRASKA TO THE SOUTHEAST OF A NORFOLK TO SIOUX CITY LINE UNTIL 10 PM
CDT.

IN ADDITION TORNADO WATCH 581 REMAINS IN EFFECT FOR MUCH OF SOUTH
CENTRAL...SOUTHEAST AND EAST CENTRAL NEBRASKA AND ADJACENT SOUTHWEST
IOWA UNTIL MIDNIGHT.

POWERS
Special weather statement, Jul 7, 7:57 PM CDT, 1 hour 2 minutes before
NEZ011-012-016>018-080300-

SPECIAL WEATHER STATEMENT CLEARING PART OF TORNADO WATCH 580
NATIONAL WEATHER SERVICE OMAHA NE
755 PM CDT MON JUL 7 1997

...TORNADO WATCH CANCELLED FOR COUNTIES IN NORTHEAST NEBRASKA TO THE
NORTH OF NORFOLK...

TORNADO WATCH NUMBER 580...ISSUED ABOUT 315 PM THIS MONDAY EVENING IS
NO LONGER IN EFFECT FOR KNOX...CEDAR...ANTELOPE...PIERCE AND WAYNE
COUNTIES OF NORTHEAST NEBRASKA.

THE SQUALL LINE AND COLD FRONT GENERATING SEVERE WEATHER HAS PASSED TO
THE SOUTHEAST OF THESE COUNTIES.

TORNADO WATCH 680 REMAINS IN EFFECT FOR THE COUNTIES OF NORTHEAST
NEBRASKA TO THE SOUTHEAST OF A NORFOLK TO SIOUX CITY LINE UNTIL 10 PM
CDT.

IN ADDITION TORNADO WATCH 581 REMAINS IN EFFECT FOR MUCH OF SOUTH
CENTRAL...SOUTHEAST AND EAST CENTRAL NEBRASKA AND ADJACENT SOUTHWEST
IOWA UNTIL MIDNIGHT.

POWERS

The office that day

Everything else NWS Omaha, NE issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 7, 7:01 PM CDTTornado WarningOAXMadison29 min
Jul 7, 7:15 PM CDTTornado WarningOAXStanton45 min
Jul 7, 7:23 PM CDTTornado WarningOAXCuming47 min
Jul 7, 7:30 PM CDTSevere Thunderstorm WarningOAXPlatte65 min
Jul 7, 7:38 PM CDTSevere Thunderstorm WarningOAXColfax62 min
Jul 7, 7:55 PM CDTTornado WarningOAXColfax50 min
Jul 7, 8:21 PM CDTSevere Thunderstorm WarningOAXDodge64 min
Jul 7, 9:18 PM CDTSevere Thunderstorm WarningOAXButler62 min
Jul 7, 9:48 PM CDTSevere Thunderstorm WarningOAXSaunders62 min
Jul 7, 10:07 PM CDTSevere Thunderstorm WarningOAXDouglas, Sarpy48 min
Jul 7, 10:10 PM CDTSevere Thunderstorm WarningOAXCass, Sarpy50 min

Nearby

Flash Flood Warnings in Nebraska, 1997Every flash flood warning in 1997

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.