Alert archive / Colorado / Flash Flood Warnings in 1996

Flash Flood Warning 8, NWS Denver/Boulder, CO

August 29, 1996Weld County, Colorado

NWS Denver/Boulder, CO issued this flash flood warning at Aug 29, 1996, 5:48 PM MDT for Weld County, Colorado. It was in force for 118 min. 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 29, 1996, 5:48 PM MDT (23:48 UTC)
Expired
Aug 29, 1996, 7:46 PM MDT
In force
118 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties

County Weld County, CO

The radar

The Cheyenne radar (KCYS), 75 km from the middle of the area, began a volume at 23:52 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 12:00Z, 11.8 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 12:00Z on 1996-08-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 12 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 12:00Z on 1996-08-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 35 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
12 J/kg
Mixed-layer CIN
-393 J/kg
Mixed-layer LCL
2160 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
35 m²/s²
0-3 km storm-relative helicity
28 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 292351
FFWDEN
COC123-300146-

BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DENVER CO
548 PM MDT THU AUG 29 1996

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A FLASH FLOOD
WARNING EFFECTIVE UNTIL 746 PM MDT FOR PEOPLE IN THE FOLLOWING
COUNTIES

IN NORTHEAST COLORADO
     NORTHWESTERN WELD

INCLUDING THE FOLLOWING LOCATIONS
     BRIGGSDALE...CARR...GROVER...NUNN...PIERCE...PURCELL AND
     ROCKPORT

AT 545 PM MDT WEATHER SERVICE DOPPLER RADAR INDICATED VERY HEAVY 
RAIN FALLING OVER NORTHWEST WELD COUNTY WITH RADAR ESTIMATES UP TO 3 
INCHES FALLING IN HOUR.  THE THUNDERSTORMS IN THIS AREA WERE NEAR 
STATIONARY AND ADDITIONAL HEAVY RAINS WILL CONTINUE FOR THE NEXT 
HOUR.

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF SMALL
CREEKS AND STREAMS. LOW LYING AREAS. HIGHWAYS...ROADS...AND
UNDERPASSES.

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. 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.

TO REPORT SEVERE WEATHER HAVE THE NEAREST LAW ENFORCEMENT AGENCY
RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE IN
DENVER.

LAT...LON 4097 10412 4062 10428 4060 10487 4096 10487

KL~EYLA

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, Aug 29, 1:45 PM MDT, 4 hours 3 minutes before
COZ030-032>050-300600-

SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO
NATIONAL WEATHER SERVICE DENVER CO
145 PM MDT THU AUG 29 1996                   ...UPDATE...

THIS OUTLOOK PERTAINS TO THE FOLLOWING COLORADO COUNTIES

ADAMS     ARAPAHOE     BOULDER   CLEAR CREEK   DENVER       DOUGLAS
ELBERT    GILPIN       GRAND     JACKSON       JEFFERSON    LARIMER
LINCOLN   LOGAN        MORGAN    PARK          PHILLIPS     SEDGWICK
SUMMIT    WASHINGTON   WELD

...STRONG WIND CONVERGENCE BOUNDARY PRIMED FOR SEVERE THUNDERSTORM
DEVELOPMENT NEXT 1 TO 2 HOURS...

SYNOPSIS:  A WELL DEVELOPED WIND CONVERGENCE BOUNDARY HAS FORMED
EAST OF THE DENVER METRO AREA EARLY THIS AFTERNOON.  THIS BOUNDARY
EXTENDS NORTHEAST FROM CASTLE ROCK IN CENTRAL DOUGLAS COUNTY TO THE
JUST EAST OF GREELEY IN EASTERN WELD COUNTY.  ALONG AND EAST OF THIS
BOUNDARY...THE ATMOSPHERE WAS VERY MOIST AND UNSTABLE CONDITIONS.
CLOUDS WERE ALREADY DEVELOPING RAPIDLY ALONG THIS BOUNDARY...WITH
THUNDERSTORM DEVELOPMENT EXPECTED BY 2:30 PM.

LATER THIS AFTERNOON THUNDERSTORM DEVELOPMENT IS EXPECTED TO BECOME
MORE WIDESPREAD WITH THE APPROACH OF A VIGOROUS UPPER LEVEL WEATHER
DISTURBANCE CURRENTLY MOVING SOUTHEAST ACROSS WYOMING.
THUNDERSTORMS LATER THIS AFTERNOON AND EARLY THIS EVENING WILL BE
CAPABLE OF LARGE DAMAGING HAIL...LOCALLY HEAVY RAIN...FUNNEL CLOUDS
AND TORNADOES.

PEOPLE IN NORTHEAST COLORADO...INCLUDING THE DENVER METRO AREA...
SHOULD BE PREPARED FOR THE POSSIBILITY OF SEVERE WEATHER LATER THIS
AFTERNOON AND EVENING.  THE BEST CHANCE FOR SEVERE WEATHER WILL BE
ALONG AND EAST OF A LINE FROM GREELEY IN WELD COUNTY TO WATKINS IN
CENTRAL ADAMS COUNTY...TO FRANKTOWN IN EASTERN DOUGLAS COUNTY.
HOWEVER...AREAS WEST OF THIS LINE MAY ALSO SEE LARGE DAMAGING HAIL...
STRONG GUSTY WINDS AND LOCALLY HEAVY RAIN.

STORM SPOTTER ACTIVATION WILL BE REQUIRED THIS AFTERNOON.

BAKER...WSFO DENVER
Special weather statement, Aug 29, 2:34 PM MDT, 3 hours 14 minutes before
COZ036-041-292050-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
230 PM MDT THU AUG 29 1996

...DOPPLER RADAR DETECTING SMALL HAIL FALLING FROM THUNDERSTORMS
OVER EXTREME SOUTHWEST DOUGLAS COUNTY...

AT 225 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
THUNDERSTORM 4 MILES EAST OF WESTCREEK...OR ABOUT 25 MILES NORTHWEST
OF COLORADO SPRINGS IN EXTREME SOUTHWEST DOUGLAS COUNTY.

DOPPLER RADAR WAS DETECTING SMALL HAIL WITH THIS STORM.

THE STORM WAS MOVING SOUTHEAST AT 30 MILES PER HOUR AND IS EXPECTED
TO MOVE INTO NORTHERN EL PASO COUNTY BY 245 PM MDT.

PERSONS IN OR NEAR DECKERS...DEVIL'S HEAD...AND LARKSPUR SHOULD BE
ON THE LOOKOUT FOR THREATENING WEAZTHER AND MOVE TO A PLACE OF SAFETY
IF BAD WEATHER APPROACHES.

A TORNADO WATCH REMAINS IN EFFECT FOR MOST OF EASTERN COLORADO UNTIL
800 PM MDT.

BAKER
Special weather statement, Aug 29, 3:13 PM MDT, 2 hours 35 minutes before
COZ041-292130-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
310 PM MDT THU AUG 29 1996

...HAIL AND LOCALLY HEAVY RAIN DETECTED ON RADAR FROM A THUNDERSTORM
IN WESTERN ELBERT COUNTY...

AT 305 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
THUNDERSTORM 4 MILES NORTH OF KIOWA...OR ABOUT 34 MILES SOUTHEAST OF
DENVER.

DOPPLER RADAR WAS DETECTING SMALL HAIL AND LOCALLY HEAVY RAIN WITH
THIS THUNDERSTORM.  RADAR HAS ALSO INDICATED SOME STRENGTHENING OF
THIS STORM IN THE PAST 10 MINUTES...A THEREFORE MAY BECOME SEVERE AS
IT MOVES ACROSS WEST CENTRAL ELBERT COUNTY.

MOVEMENT OF THIS STORM WAS TO THE SOUTHEAST AT 15 MILES PER HOUR.

PERSONS IN OR NEAR ELIZABETH AND KIOWA SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER AND MOVE TO A PLACE OF SAFETY IF BAD WEATHER
APPROACHES.

A TORNADO WATCH REMAINS IN EFFECT FOR MOST OF EASTERN COLORADO UNTIL
800 PM MDT.

BAKER...WSFO DENVER
Special weather statement, Aug 29, 3:49 PM MDT, 1 hour 59 minutes before
COZ038-040-042>045-049-292300-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
345 PM MDT THU AUG 29 1996

...SEVERE WEATHER POSSIBLE IN THE NEXT HOUR...

THUNDERSTORMS WERE DEVELOPING RAPIDLY ACROSS WELD...MORGAN...EASTERN
ADAMS AND EASTERN ARAPAHOE COUNTIES AS OF 340 PM MDT.  STORMS WERE
FORMING ALONG A WELL DEFINED WIND CONVERGENCE BOUNDARY EXTENDING
NORTH TO SOUTH ACROSS THE AREA.

AT 340 PM MDT THE STRONGEST THUNDERSTORM INDICATED ON NATIONAL
WEATHER SERVICE DOPPLER RADAR 4 MILES NORTHWEST OF HARDIN...OR ABOUT
15 MILES EAST OF GREELEY.

MOVEMENT OF STORMS IN WELD AND MORGAN COUNTIES WAS TO THE WEST AT 20
MPH...AND THOSE IN MORGAN...ADAMS AND ARAPAHOE COUNTIES TO THE
NORTHWEST AT 15 MPH.

PEOPLE IN THE ABOVE MENTIONED COUNTIES SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER AND MOVE TO A PLACE OF SAFETY IF BAD WEATHER
APPROACHES.  STORMS MAY BECOME SEVERE WITH OR NO WARNING.  LARGE
DAMAGING HAIL...HEAVY RAIN AND TORNADOES ARE POSSIBLE.

A TORNADO WATCH REMAINS IN EFFECT FOR MOST OF EASTERN COLORADO UNTIL
800 PM MDT.

BAKER...WSFO DENVER
Special weather statement, Aug 29, 4:41 PM MDT, 1 hour 7 minutes before
COZ038-039-042>045-048-049-300000-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
438 PM MDT THU AUG 29 1996

...THREATENING WEATHER APPROACHING NORTHEAST COLORADO FROM SOUTHEAST
WYOMING...

A LINE OF THUNDERSTORMS MOVING THROUGH SOUTHEAST WYOMING WERE
ASSOCIATED WITH A STRONG UPPER LEVEL WEATHER DISTURBANCE WHICH IS
FORECAST TO MOVE ACROSS NORTHEAST COLORADO THIS EVENING.

AS THIS DISTURBANCE MOVES THROUGH NORTHEAST COLORADO BETWEEN 5 AND 8
PM MDT THIS EVENING...NEW THUNDERSTORMS ARE EXPECTED TO DEVELOP...
SOME POSSIBLY SEVERE.  LARGE DAMAGING HAIL...LOCALLY HEAVY RAIN AND
TORNADOES WILL BE POSSIBLE WITH THESE STORMS.

PEOPLE IN NORTHEAST COLORADO SHOULD REMAIN ALERT FOR THREATENING
WEATHER THIS EVENING AND MOVE TO A PLACE OF SAFETY IF SEVERE WEATHER
APPROACHES.  STORMS MAY BECOME SEVERE WITH OR NO WARNING.  LARGE
DAMAGING HAIL...HEAVY RAIN AND TORNADOES ARE POSSIBLE.

A TORNADO WATCH REMAINS IN EFFECdT FOR MOST OF EASTERN COLORADO UNTIL
800 PM MDT.

BAKER...WSFO DENVER

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 28, 6:14 PM MDTSevere Thunderstorm WarningBOUWashington31 min
Aug 29, 3:25 PM MDTSevere Thunderstorm WarningBOUElbert45 min
Aug 29, 4:00 PM MDTSevere Thunderstorm WarningBOUWeld60 min
Aug 29, 4:25 PM MDTTornado WarningBOUMorgan, Weld35 min
Aug 29, 4:53 PM MDTSevere Thunderstorm WarningBOUElbert42 min
Aug 29, 5:08 PM MDTSevere Thunderstorm WarningBOUWeld52 min
Aug 29, 5:10 PM MDTSevere Thunderstorm WarningBOUAdams, Morgan, Weld30 min
Aug 29, 5:12 PM MDTSevere Thunderstorm WarningBOULogan58 min

Nearby

Flash Flood Warnings in Colorado, 1996Every flash flood warning in 1996

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.