Alert archive / Colorado / Flash Flood Warnings in 1998

Flash Flood Warning 7, NWS Denver/Boulder, CO

July 24, 1998Adams County, Arapahoe County, Colorado

NWS Denver/Boulder, CO issued this flash flood warning at Jul 24, 1998, 8:28 PM MDT for Adams County, Arapahoe County, Colorado. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties.

The facts

Issued
Jul 24, 1998, 8:28 PM MDT (02:28 UTC)
Expired
Jul 24, 1998, 11:30 PM MDT
In force
3 hr
Issued by
NWS Denver/Boulder, CO
Area
Whole counties; the outline is the Mesonet’s reconstruction

Counties Adams County, CO, Arapahoe County, CO

The nearest sounding before it

Denver, CO (KDNR), launched 00:00Z, 2.5 hours before the alert went out and 65 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, Denver, CO at 00:00Z on 1998-07-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 166 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, Denver, CO at 00:00Z on 1998-07-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 48 square meters per square second.1939Sfc1 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
166 J/kg
Mixed-layer CIN
-37 J/kg
Mixed-layer LCL
1389 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
48 m²/s²
0-3 km storm-relative helicity
58 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KDEN 250229
FFWDEN
COC001-005-250530-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DENVER CO
828 PM MDT FRI JUL 24 1998

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

* FLASH FLOOD WARNING FOR...
     EXTREME SOUTHEASTERN ADAMS COUNTY IN NORTHEAST COLORADO
     EASTERN ARAPAHOE COUNTY IN NORTHEAST COLORADO

* UNTIL 1130 PM MDT

* AT 825 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  EXTRMELY HEAVY RAIN FROM DEER TRAIL TO SHAMROCK...OR FROM ABOUT 
  28 MILES NORTHWEST OF LIMON TO 30 MILES SOUTHWEST OF AKRON.  

RADAR INDICATES BETWEEN 3 AND 4 INCHES OF RAIN HAS FALLEN IN THIS 
AREA DURING THE LAST TWO HOURS.  ANOTHER INCH OR TWO OF RAIN MAY 
FALL BEFORE DIMINISHING BY 10 PM.  

TOWNS IN THE WARNING INCLUDE...
    DEER TRAIL

CREEKS AND STREAMS IN THE WARNING INCLUDE...
    MIDDLE BIJOU CREEK...EAST BIJOU CREEK...AND MUDDY CREEK.  

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF 
CREEKS AND STREAMS...COUNTRY ROADS...NORMALLY DRY WASHES AND
ARROYOS...AS WELL AS FARMLAND ALONG THE BANKS OF CREEKS AND STREAMS.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODS AND FLASH FLOODS. IF FLASH FLOODING IS OBSERVED ACT
QUICKLY. MOVE UP TO HIGHER GROUND TO ESCAPE FLOOD WATERS. DO NOT STAY
IN AREAS SUBJECT TO FLOODING WHEN WATER BEGINS RISING.

LAT...LON 3978 10382 3957 10397 3957 10415 3985 10403

BARJENBRUCH

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 24, 3:02 PM MDT, 5 hours 26 minutes before
COZ036-242130-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
302 PM MDT FRI JUL 24 1998

...THUNDERSTORMS DEVELOPING IN SOUTHERN JEFFERSON COUNTY NEAR
BUFFALO CREEK...

AT 257 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
THUNDERSTORMS DEVELOPING RAPIDLY NEAR BUFFALO CREEK.  THESE STORMS
MAY PRODUCE UP TO 1 1/2 INCHES OF RAIN IN LESS THAN AN HOUR ALONG
WITH DANGEROUS LIGHTNING.

PERSONS IN THE TOWN OF BUFFALO CREEK AND ALONG THE CREEK ITSELF
SHOULD BE PREPARED FOR HEAVY RAINS WHICH MAY FLOOD LOW LYING AREAS.
DO NOT CROSS FLOODED ROADS AS THEY MAY BE WASHED OUT. WATER LEVELS
OF SMALL STREAMS AND RIVERS MAY ALSO RISE...THEREFORE SEEK HIGHER
GROUND IF THREATENED BY FLOOD WATERS.

KLEYLA
Special weather statement, Jul 24, 3:02 PM MDT, 5 hours 26 minutes before
COZ036-242130-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
302 PM MDT FRI JUL 24 1998

...THUNDERSTORMS DEVELOPING IN SOUTHERN JEFFERSON COUNTY NEAR
BUFFALO CREEK...

AT 257 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
THUNDERSTORMS DEVELOPING RAPIDLY NEAR BUFFALO CREEK.  THESE STORMS
MAY PRODUCE UP TO 1 1/2 INCHES OF RAIN IN LESS THAN AN HOUR ALONG
WITH DANGEROUS LIGHTNING.

PERSONS IN THE TOWN OF BUFFALO CREEK AND ALONG THE CREEK ITSELF
SHOULD BE PREPARED FOR HEAVY RAINS WHICH MAY FLOOD LOW LYING AREAS.
DO NOT CROSS FLOODED ROADS AS THEY MAY BE WASHED OUT. WATER LEVELS
OF SMALL STREAMS AND RIVERS MAY ALSO RISE...THEREFORE SEEK HIGHER
GROUND IF THREATENED BY FLOOD WATERS.

KLEYLA
Special weather statement, Jul 24, 6:37 PM MDT, 1 hour 51 minutes before
COZ039>040-250200-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
637 PM MDT FRI JUL 24 1998

...THUNDERSTORMS WITH VERY HEAVY RAIN WILL QUICKLY DEVELOP IN THE
DENVER METRO AREA...

THE ATMOSPHERE IS PRIMED FOR THE DEVELOPMENT OF HEAVY RAIN IN THE
DENVER AND BOULDER METRO AREAS THIS EVENING.  AT 630 PM MDT...
NATIONAL WEATHER SERVICE RADAR WAS SHOWING THE FIRST SIGNS OF
THUNDERSTORM DEVELOPMENT OVER THE NORTHERN AND WESTERN PORTIONS OF
THE METRO AREA.  THESE STORMS ARE EXPECTED TO QUICKLY DEVELOP AND
INCREASE IN BOTH SIZE AND INTENSITY DURING THE NEXT HOUR.

EXTREMELY HEAVY RAINFALL OF 1.5 TO 2.5 INCHES PER HOUR CAN BE
EXPECTED WITH THE STRONGER STORMS.  THIS MAY CAUSE FLOODING OF
ROADS...INTERSECTIONS...AND UNDERPASSES...AS WELL AS SMALL CREEKS
AND STREAMS IN THE METROPOLITAN AREA.

STAY TUNED TO THE NATIONAL WEATHER SERVICE OR YOUR LOCAL NEWS MEDIA
FOR THE LATEST UPDATES AND/OR WARNINGS.

BARJENBRUCH
Special weather statement, Jul 24, 6:37 PM MDT, 1 hour 51 minutes before
COZ039>040-250200-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
637 PM MDT FRI JUL 24 1998

...THUNDERSTORMS WITH VERY HEAVY RAIN WILL QUICKLY DEVELOP IN THE
DENVER METRO AREA...

THE ATMOSPHERE IS PRIMED FOR THE DEVELOPMENT OF HEAVY RAIN IN THE
DENVER AND BOULDER METRO AREAS THIS EVENING.  AT 630 PM MDT...
NATIONAL WEATHER SERVICE RADAR WAS SHOWING THE FIRST SIGNS OF
THUNDERSTORM DEVELOPMENT OVER THE NORTHERN AND WESTERN PORTIONS OF
THE METRO AREA.  THESE STORMS ARE EXPECTED TO QUICKLY DEVELOP AND
INCREASE IN BOTH SIZE AND INTENSITY DURING THE NEXT HOUR.

EXTREMELY HEAVY RAINFALL OF 1.5 TO 2.5 INCHES PER HOUR CAN BE
EXPECTED WITH THE STRONGER STORMS.  THIS MAY CAUSE FLOODING OF
ROADS...INTERSECTIONS...AND UNDERPASSES...AS WELL AS SMALL CREEKS
AND STREAMS IN THE METROPOLITAN AREA.

STAY TUNED TO THE NATIONAL WEATHER SERVICE OR YOUR LOCAL NEWS MEDIA
FOR THE LATEST UPDATES AND/OR WARNINGS.

BARJENBRUCH

The office that day

Everything else NWS Denver/Boulder, CO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 25, 2:44 PM MDTTornado WarningBOULarimer, Weld26 min
Jul 25, 4:15 PM MDTSevere Thunderstorm WarningBOULogan30 min
Jul 25, 4:29 PM MDTFlash Flood WarningBOULogan3 hr
Jul 25, 4:50 PM MDTFlash Flood WarningBOUClear Creek115 min
Jul 25, 5:03 PM MDTTornado WarningBOUAdams, Denver27 min
Jul 25, 5:07 PM MDTFlash Flood WarningBOUMorgan3 hr
Jul 25, 5:35 PM MDTFlash Flood WarningBOUWashington2 hr
Jul 25, 5:41 PM MDTFlash Flood WarningBOUWashington2 hr

Nearby

Flash Flood Warnings in Colorado, 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.