Alert archive / Nebraska / Flash Flood Warnings in 1998

Flash Flood Warning 32, NWS Omaha, NE

August 21, 1998Saunders County, Nebraska

NWS Omaha, NE issued this flash flood warning at Aug 21, 1998, 6:05 AM CDT for Saunders County, Nebraska. It was in force for 4 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
Aug 21, 1998, 6:05 AM CDT (11:05 UTC)
Expired
Aug 21, 1998, 10:00 AM CDT
In force
4 hr
Issued by
NWS Omaha, NE
Area
Whole counties

County Saunders County, NE

The radar

The Omaha radar (KOAX), 25 km from the middle of the area, began a volume at 11:04 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

Topeka, KS (KTOP), launched 00:00Z, 11.1 hours before the alert went out and 262 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, Topeka, KS at 00:00Z on 1998-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1580 joules per kilogram.LCLLFCEL10008507005003002001001 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, Topeka, KS at 00:00Z on 1998-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 21 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
1580 J/kg
Mixed-layer CIN
-28 J/kg
Mixed-layer LCL
1726 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
21 m²/s²
0-3 km storm-relative helicity
78 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.2

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KOMA 211107
FFWOMA
NEC155-211500-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
605 AM CDT FRI AUG 21 1998

THE NATIONAL WEATHER SERVICE IN OMAHA HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SAUNDERS COUNTY IN EAST CENTRAL NEBRASKA

* UNTIL 1000 AM CDT

* AT 605 AM CDT...RADAR INDICATED THAT THREE TO FIVE INCHES OF RAIN
  HAD OCCURRED ACROSS MUCH OF SAUNDERS COUNTY DURING THE NIGHT.  MORE
  THUNDERSTORMS WILL BE SCATTERED ACROSS THE AREA EARLY THIS
  MORNING...SO EVEN MORE RAIN IS POSSIBLE.

SOME STREAMS AFFECTED INCLUDE...WAHOO CREEK...SAND CREEK...SILVER
CREEK.

DO NOT DRIVE ACROSS FLOODED ROADS.  MOST FLASH FLOOD DEATHS OCCUR
IN AUTOMOBILES.  IF YONUR VEHICLE STALLS...ABANDON IT IMMEDIATELY
AND SEEK HIGHER GROUND.

MILLER

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

Local storm report, Aug 21, 4:14 AM CDT, 1 hour 51 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
414 AM CDT FRI AUG 21 1998

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

1155 PM    OFFUTT AFB                NE   84 MPH TSTM GUST
08/20/98   SARPY

1201 AM    OFFUTT AFB                NE   57 MPH TSTM GUST
08/21/98   SARPY
Local storm report, Aug 21, 4:14 AM CDT, 1 hour 51 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
414 AM CDT FRI AUG 21 1998

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

1155 PM    OFFUTT AFB                NE   84 MPH TSTM GUST
08/20/98   SARPY

1201 AM    OFFUTT AFB                NE   57 MPH TSTM GUST
08/21/98   SARPY
Special weather statement, Aug 21, 5:10 AM CDT, 55 minutes before
NEZ011-012-015>018-030>034-042>045-050>053-065>068-078-088>093-
IAZ043-055-056-069-079-080-090-091-221200-

SEVERE WEATHER OUTLOOK
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
510 AM CDT FRI AUG 21 1998

...SEVERE WEATHER OUTLOOK FOR EASTERN NEBRASKA AND SOUTHWEST IOWA...

SPOTTER ACTION...
STORM SPOTTER ACTIVATION MAY BE NEEDED IN PARTS OF NORTHEAST NEBRASKA
TODAY...BUT IT WILL PROBABLY NOT BE NEED OVER THE REMAINDER OF EASTERN
NEBRASKA AND SOUTHWEST IOWA TODAY OR TONIGHT.

DISCUSSION...
A FRONT EXTENDS FROM EAST TO WEST THROUGH THE AREA.  SHOWERS AND
THUNDERSTORMS WILL BE WIDESPREAD ACROSS A LARGE PART OF EASTERN
NEBRASKA AND SOUTHWEST IOWA THROUGH THE MORNING.  THE GREATEST THREAT
FROM THESE STORMS IS HEAVY RAIN...WHICH COULD CAUSE FLOODING.  A FEW
STORMS COULD PRODUCE STRONG WINDS AND HAIL.
>
STORMS SHOULD DECREASE IN COVERAGE THIS AFTERNOON...BUT MAY REDEVELOP
NEAR THE FRONT TOWARD EVENING AS THE FRONT LIFTS BACK NORTH.

MILLER
Special weather statement, Aug 21, 5:10 AM CDT, 55 minutes before
NEZ011-012-015>018-030>034-042>045-050>053-065>068-078-088>093-
IAZ043-055-056-069-079-080-090-091-221200-

SEVERE WEATHER OUTLOOK
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
510 AM CDT FRI AUG 21 1998

...SEVERE WEATHER OUTLOOK FOR EASTERN NEBRASKA AND SOUTHWEST IOWA...

SPOTTER ACTION...
STORM SPOTTER ACTIVATION MAY BE NEEDED IN PARTS OF NORTHEAST NEBRASKA
TODAY...BUT IT WILL PROBABLY NOT BE NEED OVER THE REMAINDER OF EASTERN
NEBRASKA AND SOUTHWEST IOWA TODAY OR TONIGHT.

DISCUSSION...
A FRONT EXTENDS FROM EAST TO WEST THROUGH THE AREA.  SHOWERS AND
THUNDERSTORMS WILL BE WIDESPREAD ACROSS A LARGE PART OF EASTERN
NEBRASKA AND SOUTHWEST IOWA THROUGH THE MORNING.  THE GREATEST THREAT
FROM THESE STORMS IS HEAVY RAIN...WHICH COULD CAUSE FLOODING.  A FEW
STORMS COULD PRODUCE STRONG WINDS AND HAIL.
>
STORMS SHOULD DECREASE IN COVERAGE THIS AFTERNOON...BUT MAY REDEVELOP
NEAR THE FRONT TOWARD EVENING AS THE FRONT LIFTS BACK NORTH.

MILLER

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 20, 7:29 PM CDTSevere Thunderstorm WarningOAXCass, Douglas, Sarpy, Saunders61 min
Aug 20, 7:42 PM CDTSevere Thunderstorm WarningOAXDodge, Washington63 min
Aug 20, 11:46 PM CDTFlash Flood WarningOAXSarpy, Saunders4 hr
Aug 20, 11:59 PM CDTSevere Thunderstorm WarningOAXSarpy46 min
Aug 21, 12:53 AM CDTSevere Thunderstorm WarningOAXSaunders62 min

Nearby

Flash Flood Warnings in Nebraska, 1998Every 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.