Alert archive / Colorado / Flash Flood Warnings in 1997

Flash Flood Warning 14, NWS Denver/Boulder, CO

July 28, 1997Larimer County, Colorado

NWS Denver/Boulder, CO issued this flash flood warning at Jul 28, 1997, 9:40 PM MDT for Larimer County, Colorado. It was in force for 2 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 28, 1997, 9:40 PM MDT (03:40 UTC)
Expired
Jul 29, 1997, 12:00 AM MDT
In force
2 hr
Issued by
NWS Denver/Boulder, CO
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Larimer County, CO

The radar

The Cheyenne radar (KCYS), 63 km from the middle of the area, began a volume at 03:40 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

Denver, CO (KDNR), launched 00:00Z, 3.7 hours before the alert went out and 184 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 1997-07-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 733 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 1997-07-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 90 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
733 J/kg
Mixed-layer CIN
-24 J/kg
Mixed-layer LCL
1050 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
90 m²/s²
0-3 km storm-relative helicity
122 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.6

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KDEN 290349 COR
FFWDEN
COC069-290600-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING...RESTRANSMITTED 
NATIONAL WEATHER SERVICE DENVER CO
940 PM MDT MON JUL 28 1997

...THIS IS A DANGEROUS SITUATION...      

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A FLASH FLOOD 
WARNING EFFECTIVE UNTIL MIDNIGHT MDT FOR PEOPLE IN THE FOLLOWING 
COUNTIES

IN NORTH CENTRAL COLORADO
     EASTERN LARIMER

INCLUDING THE FOLLOWING LOCATIONS
     FORT COLLINS...BELLVUE...HARMONY...LIVERMORE...MASONVILLE AND
     TEDS PLACE

AT 934 PM MDT...THE LARIMER COUNTY SHERIFF REPORTED FLOODING OF 
HOMES IN TAFT CANYON ESTATES...BETWEEN FORT COLLINS AND HORSETOOTH 
RESERVOIR.  BETWEEN 3 AND 4 INCHES OF RAIN HAS ALREADY FALLEN IN 
THIS AREA.  

MORE HEAVY RAIN WILL CONTINUE THROUGH 11 PM OVER EASTERN LARIMER 
COUNTY.  RAINFALL RATES OF 1 TO 2 INCHES PER HOUR WILL CAUSE 
ADDITIONAL FLOODING PROBLEMS.  THIS IS A DANGEROUS SITUATION!

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING. 
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY. 
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE 
PRECAUTIONS TO PROTECT LIFE AND PROPERTY.  DO NOT ATTEMPT TO CROSS 
SWIFTL4Y FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY 
AUTOMOBILE.

THE HEAVY RAINS COULD ALSO TRIGGER ROCK AND MUDSLIDES IN STEEP 
TERRAIN.

BARJENBRUCH 

LAT...LON 4043 10507 4041 10528 4098 10529 4100 10502

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 28, 3:59 PM MDT, 5 hours 41 minutes before
COZ034-036-037-040-282300-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
400 PM MDT MON JUL 28 1997

...THUNDERSTORMS WITH HEAVY RAIN IN THE FOOTHILLS WEST OF
DENVER...

AT 400 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
A LINE OF THUNDERSTORMS FROM JUST WEST OF GOLDEN TO BAILEY...AND
THEN INTO CENTRAL PARK COUNTY.  THE STRONGEST STORM WAS OVER
EVERGREEN...OR ABOUT 20 MILES SOUTHWEST OF DOWNTOWN DENVER.

THE STORMS WERE MOVING VERY SLOWLY NORTHEAST AT 5 MILES PER HOUR.

PERSONS IN OR NEAR GOLDEN...ANTERO RESERVOIR...ASPEN PARK...BAILEY...
BERGEN PARK...COMO...CONIFER...EVERGREEN...FAIRPLAY...PARK...
HARTSEL...HIGHLAND PARK...IDLEDALE...INDIAN HILLS...JEFFERSON...
KITTREDGE...PINE...RED HILL PASS...SHAWNEE...TARRYALL
RESERVOIR...TINY TOWN...WELLINGTON LAKE AND WHITE RANCH OPEN SPACE
SHOULD BE ON THE LOOKOUT FOR VERY HEAVY RAIN.

THE STRONGEST STORMS IN THIS LINE WILL PRODUCE BETWEEN 1 AND 2
INCHES OF RAIN IN AN HOUR.

HEAVY RAINS MAY FLOOD LOW LYING AREAS SUCH AS DITCHES AND
UNDERPASSES.  AVOID THESE AREAS AND DO NOT CROSS FLOODED ROADS AS
THEY MAY BE WASHED OUT.  WATER LEVELS OF SMALL STREAMS AND RIVERS
MAY ALSO RISE...THEREFOtRE SEEK HIGHER GROUND IF THREATENED BY FLOOD
WATERS.

BARJENBRUCH
Special weather statement, Jul 28, 4:00 PM MDT, 5 hours 40 minutes before
COZ034-036-037-040-282300-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
400 PM MDT MON JUL 28 1997

...THUNDERSTORMS WITH HEAVY RAIN IN THE FOOTHILLS WEST OF
DENVER...

AT 400 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
A LINE OF THUNDERSTORMS FROM JUST WEST OF GOLDEN TO BAILEY...AND
THEN INTO CENTRAL PARK COUNTY.  THE STRONGEST STORM WAS OVER
EVERGREEN...OR ABOUT 20 MILES SOUTHWEST OF DOWNTOWN DENVER.

THE STORMS WERE MOVING VERY SLOWLY NORTHEAST AT 5 MILES PER HOUR.

PERSONS IN OR NEAR GOLDEN...ANTERO RESERVOIR...ASPEN PARK...BAILEY...
BERGEN PARK...COMO...CONIFER...EVERGREEN...FAIRPLAY...PARK...
HARTSEL...HIGHLAND PARK...IDLEDALE...INDIAN HILLS...JEFFERSON...
KITTREDGE...PINE...RED HILL PASS...SHAWNEE...TARRYALL
RESERVOIR...TINY TOWN...WELLINGTON LAKE AND WHITE RANCH OPEN SPACE
SHOULD BE ON THE LOOKOUT FOR VERY HEAVY RAIN.

THE STRONGEST STORMS IN THIS LINE WILL PRODUCE BETWEEN 1 AND 2
INCHES OF RAIN IN AN HOUR.

HEAVY RAINS MAY FLOOD LOW LYING AREAS SUCH AS DITCHES AND
UNDERPASSES.  AVOID THESE AREAS AND 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.

BARJENBRUCH
Special weather statement, Jul 28, 6:17 PM MDT, 3 hours 23 minutes before
COZ040-290045-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
617 PM MDT MON JUL 28 1997

...THUNDERSTORMS WITH STRONG GUSTY WINDS AND TORRENTIAL RAIN MOVING
THROUGH AURORA...

AT 617 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
LARGE AREA OF THUNDERSTORMS OVER AURORA.  THESE STORMS WERE
PRODUCING WIND GUSTS UP TO 50 MPH...AND TORRENTIAL RAIN.  BRIEF
FUNNEL CLOUDS WERE ALSO REPORTED NEAR BUCKLEY.

THE STORM WAS MOVING NORTHEAST AT 20 MILES PER HOUR.

PERSONS IN OR NEAR AURORA...EASTERN DENVER...ARAPAHOE PARK...BEVERLY
HILLS...GREENWOOD VILLAGE...PARKER AND SURREY RIDGE SHOULD BE ON THE
LOOKOUT FOR DANGEROUS WEATHER CONDITIONS.  MOVE INSIDE A STURDY
STRUCTURE AND STAY AWAY FROM WINDOWS.

FLOODING OF ROADS...HIGHWAYS...DITCHES...AND OTHER LOW LYING AREAS
WILL OCCUR WITH THESE STORMS.  DO NOT DRIVE THROUGH FLOODED AREAS.

BARJENBRUCH
Special weather statement, Jul 28, 6:21 PM MDT, 3 hours 19 minutes before
COZ040-290045-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
617 PM MDT MON JUL 28 1997

...THUNDERSTORMS WITH STRONG GUSTY WINDS AND TORRENTIAL RAIN MOVING
THROUGH AURORA...

AT 617 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
LARGE AREA OF THUNDERSTORMS OVER AURORA.  THESE STORMS WERE
PRODUCING WIND GUSTS UP TO 50 MPH...AND TORRENTIAL RAIN.  BRIEF
FUNNEL CLOUDS WERE ALSO REPORTED NEAR BUCKLEY.

THE STORM WAS MOVING NORTHEAST AT 20 MILES PER HOUR.

PERSONS IN OR NEAR AURORA...EASTERN DENVER...ARAPAHOE PARK...BEVERLY
HILLS...GREENWOOD VILLAGE...PARKER AND SURREY RIDGE SHOULD BE ON THE
LOOKOUT FOR DANGEROUS WEATHER CONDITIONS.  MOVE INSIDE A STURDY
STRUCTURE AND STAY AWAY FROM WINDOWS.

FLOODING OF ROADS...HIGHWAYS...DITCHES...AND OTHER LOW LYING AREAS
WILL OCCUR WITH THESE STORMS.  DO NOT DRIVE THROUGH FLOODED AREAS.

BARJENBRUCH
Special weather statement, Jul 28, 9:28 PM MDT, 12 minutes before
COZ040-290430-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
928 PM MDT MON JUL 28 1997

...MORE THUNDERSTORMS WITH HEAVY RAIN IN THE DENVER METRO AREA...

AT 926 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
THUNDERSTORM WITH VERY HEAVY RAIN OVER NORTHEAST ARVADA...
WESTMINSTER AND FEDERAL HEIGHTS.

A WEATHER SPOTTER AT 76TH AND SHERIDAN REPORTED 1 INCH OF RAIN IN 24
MINUTES AS THIS STORM PASSED OVERHEAD.

THE STORM WAS MOVING NORTHEAST AT 20 MILES PER HOUR.

PERSONS IN OR NEAR NORTHEAST ARVADA...NORTHGLENN...THORNTON...
WESTMINSTER...BRIGHTON AND FEDERAL HEIGHTS SHOULD BE ON THE LOOKOUT
FOR VERY HEAVY RAIN.

HEAVY RAINS MAY FLOOD LOW LYING AREAS SUCH AS DITCHES AND
UNDERPASSES.  AVOID THESE AREAS AND DO NOT CROSS FLOODED ROADS.

BARJENBRUCH
Special weather statement, Jul 28, 9:31 PM MDT, 9 minutes before
COZ040-290430-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
928 PM MDT MON JUL 28 1997

...MORE THUNDERSTORMS WITH HEAVY RAIN IN THE DENVER METRO AREA...

AT 926 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
THUNDERSTORM WITH VERY HEAVY RAIN OVER NORTHEAST ARVADA...
WESTMINSTER AND FEDERAL HEIGHTS.

A WEATHER SPOTTER AT 76TH AND SHERIDAN REPORTED 1 INCH OF RAIN IN 24
MINUTES AS THIS STORM PASSED OVERHEAD.

THE STORM WAS MOVING NORTHEAST AT 20 MILES PER HOUR.

PERSONS IN OR NEAR NORTHEAST ARVADA...NORTHGLENN...THORNTON...
WESTMINSTER...BRIGHTON AND FEDERAL HEIGHTS SHOULD BE ON THE LOOKOUT
FOR VERY HEAVY RAIN.

HEAVY RAINS MAY FLOOD LOW LYING AREAS SUCH AS DITCHES AND
UNDERPASSES.  AVOID THESE AREAS AND DO NOT CROSS FLOODED ROADS.

BARJENBRUCH

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 28, 6:41 PM MDTFlash Flood WarningBOUAdams2 hr
Jul 28, 6:58 PM MDTFlash Flood WarningBOUWeld2 hr
Jul 28, 7:55 PM MDTTornado WarningBOUElbert35 min
Jul 29, 3:50 PM MDTTornado WarningBOUArapahoe, Elbert40 min
Jul 29, 4:38 PM MDTFlash Flood WarningBOUElbert112 min
Jul 29, 5:37 PM MDTFlash Flood WarningBOUElbert113 min

Nearby

Flash Flood Warnings in Colorado, 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.