Alert archive / Colorado / Flash Flood Warnings in 1997

Flash Flood Warning 13, NWS Denver/Boulder, CO

July 28, 1997Weld County, Colorado

NWS Denver/Boulder, CO issued this flash flood warning at Jul 28, 1997, 6:58 PM MDT for Weld 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, 6:58 PM MDT (00:58 UTC)
Expired
Jul 28, 1997, 9:00 PM MDT
In force
2 hr
Issued by
NWS Denver/Boulder, CO
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Weld County, CO

The radar

The Denver radar (KFTG), 43 km from the middle of the area, began a volume at 01:01 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, 1.0 hours before the alert went out and 125 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°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 290057
FFWDEN
COC123-290300-

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

THE NATIONAL WEATHER SERVICE IN DENVER HAS EXTENDED THE FLASH FLOOD 
WARNING EFFECTIVE UNTIL 900 PM MDT FOR PEOPLE IN THE FOLLOWING 
COUNTIES

IN NORTHEAST COLORADO
     SOUTHWESTERN WELD

INCLUDING AREAS NORTHEAST OF FORT LUPTON AND NORTHWEST OF HUDSON 

AT 655 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED UP 
TO 6 INCHES OF RAIN HAD FALLEN 5 MILES MILES NORTHWEST OF 
HUDSON...OR ABOUT 25 MILES NORTHEAST OF DENVER.  THUNDERSTORMS 
CONTINUED OVER THE AREA...AND UP TO ANOTHER INCH OF RAIN CAN BE 
EXPECTED BEFORE IT ENDS LATER THIS EVENING.  

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

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...INCLUDING BOX ELDER 
CREEK AND BEEBE SEEP CANAL...SHOULD TAKE IMMEDIATE PRECAUTIONS TO 
PROTECT LIFE AND PROPERTY.  DO NOT ATTEMPT TO CROSS SWIFTLY FLOWING 
WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY AUTOMOBILE.  IF YOUR 
VEHICLE STALLS, ABANDON IT IMMEDIATELY AND SEEK HIGHER GROUND.

BARJENBRUCH 

LAT...LON 4023 10461 4023 10455 4012 10458 4005 10473 
         4010 10479 4021 10467

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, 7:55 PM MDTTornado WarningBOUElbert35 min
Jul 28, 9:40 PM MDTFlash Flood WarningBOULarimer2 hr
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.