Alert archive / Colorado / Flash Flood Warnings in 1996

Flash Flood Warning 7, NWS Denver/Boulder, CO

August 23, 1996Jefferson County, Colorado

NWS Denver/Boulder, CO issued this flash flood warning at Aug 23, 1996, 4:06 PM MDT for Jefferson County, Colorado. It was in force for 84 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 23, 1996, 4:06 PM MDT (22:06 UTC)
Expired
Aug 23, 1996, 5:30 PM MDT
In force
84 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties

County Jefferson County, CO

The radar

The Denver radar (KFTG), 64 km from the middle of the area, began a volume at 22:06 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

Fort Carson/Butt, CO (KFCS), launched 12:00Z, 10.1 hours before the alert went out and 111 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, Fort Carson/Butt, CO at 12:00Z on 1996-08-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Fort Carson/Butt, CO at 12:00Z on 1996-08-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 37 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
2 J/kg
Mixed-layer CIN
-32 J/kg
Mixed-layer LCL
826 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
37 m²/s²
0-3 km storm-relative helicity
24 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 232210
FFWDEN
COC059-232330-

BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DENVER CO
406 PM MDT FRI AUG 23 1996

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A FLASH FLOOD 
WARNING EFFECTIVE UNTIL 530 PM MDT FOR PEOPLE IN THE FOLLOWING 
COUNTIES

IN NORTHEAST COLORADO
     SOUTHERN JEFFERSON

INCLUDING THE FOLLOWING LOCATIONS
     BUFFALO CREEK...FERNDALE...AND FOXTON. 

AT 405PM MDT JEFFERSON COUNTY SHERRIF REPORTS FLASH FLOODING IN THE 
BUFFALO CREEK AREA.  HIGHWAY 126 HAS BEEN CLOSED.   BUFFALO CREEK...
SAND DRAW...AND THE NORTH FORK OF THE SOUTH PLATTE WILL BE DIRECTLY 
EFFECTED BY THE EXCESSIVE RUNOFF.   

DOPPLER RADAR HAS INDICATED RAINFALL RATES OF AN INCH AN HOUR SOUTH 
OF PINE...AND WEST OF DECKERS.  RAIN FALLING ON THE BUFFALO CREEK 
BURN AREA WILL RUN OFF VERY QUICKLY.  

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 3943 10519 3926 10520 3923 10535 3938 10535
RTG

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 23, 11:15 AM MDT, 4 hours 51 minutes before
COZ030-032>050-230600-

SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO
NATIONAL WEATHER SERVICE DENVER CO
1115 AM MDT FRI AUG 23 1996

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

SYNOPSIS:  A MOIST UNSTABLE AIRMASS WILL AGAIN SIT AGAINST THE
FOOTHILLS TODAY.  A RIDGE OF HIGH PRESSURE RESIDES OVER THE STATE...
AND WINDS THROUGH THE ATMOSPHERE ARE VERY LIGHT.  THUNDERSTORMS WILL
DEVELOP OVER THE MOUNTAINS AFTER NOON...AND MOVE TO THE LOWER
ELEVATIONS AFTER 3PM.  THESE STORMS WILL MOVE VERY SLOWLY...ALLOWING
1 TO 2 INCHES OF RAIN TO FALL IN AN HOUR OVER LOCAL AREAS LATE THIS
AFTERNOON.  THE PRIME LOCATIONS FOR THIS HEAVY RAIN APPEAR TO BE FROM
THE FOOTHILLS...EASTWARD TO WESTERN WELD AND WESTERN ELBERT COUNTIES.
THESE AREAS ARE BEING CONSIDERED FOR A FLASH FLOOD WATCH LATER
THIS AFTERNOON.

FURTHER EAST THE AIRMASS IS MORE STABLE...AND THUNDERSTORMS ARE NOT
EXPECTED EAST OF AKRON AND STERLING.

SPOTTERS MAY RAGAIN BE NEEDED FOR RAINFALL RATES AND LOCAL FLOODING
REPORTS THIS AFTERNOON.

RTG
Special weather statement, Aug 23, 2:45 PM MDT, 1 hour 21 minutes before
COZ041-232300-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
245 PM MDT THU AUG 22 1996

...HEAVY RAIN IN DOUGLAS COUNTY...

AT 232 PM DOPPLER RADAR SHOWED AN AREA OF VERY HEAVY RAIN IN EASTERN
DOUGLAS COUNTY.  THE AREA WAS ABOUT 10 MILES SOUTH OF FRANKTOWN
ALONG CHERRY CREEK...AND RAINFALL HAS EXCEEDED 1.5 INCHES IN THE
PAST HOUR.  THE STORM WAS NEARLY STATIONARY.

ANYONE LIVING IN EASTERN DOUGLAS COUNTY SHOULD BE PREPARED FOR
VERY HEAVY RAIN OVER THE NEXT TWO HOURS.  SOME LOCAL FLOODING OF LOW
LYING ROADS MAY OCCUR.  DO NOT ATTEMPT TO DRIVE THROUGH FLOODED
AREAS...AS YOU WILL LOSE CONTROL OF YOUR CAR QUICKLY IN RUNNING
WATER.

A FLASH FLOOD WATCH WILL BE IN EFFECT FOR DOUGLAS COUNTY...AND THE
FOOTHILLS AND ADJACENT PLAINS OF COLORADO UNTIL MIDNIGHT TONIGHT.

RTG
Special weather statement, Aug 23, 3:07 PM MDT, 59 minutes before
COZ040-232300-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
305 PM MDT FRI AUG 23 1996

...ANOTHER WET RUSH HOUR IN THE DENVER AREA?...

AT 301PM NATIONAL WEATHER SERVICE DOPPLER RADAR SHOWED NEW
THUNDERSTORMS DEVELOPING RAPIDLY OVER THE SOUTHERN AND EASTERN METRO
AREAS FROM NEAR CHATFIELD RESERVOIR...ACROSS LITTLETON TO AURORA.
IT LOOKS LIKE ANOTHER WET COMMUNTE THIS AFTERNOON.   THUNDERSTORMS
TODAY HAVE BEEN MOVING VERY SLOWLY...WITH RAINFALL RATES LOCALLY
REACHING 1.5 INCHES AN HOUR.  A FLASH FLOOD WATCH REMAINS IN EFFECT
FOR THE DENVER AREA THROUGH MIDNIGHT TONIGHT.

RTG
Special weather statement, Aug 23, 3:45 PM MDT, 21 minutes before
COZ040-232345-

URBAN AND SMALL STREAM FLOOD ADVISORY
NATIONAL WEATHER SERVICE DENVER CO
339 PM MDT FRI AUG 23 1996

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED AN URBAN AND SMALL
STREAM FLOOD ADVISORY EFFECTIVE UNTIL 545 PM MDT FOR PEOPLE IN THE
FOLLOWING COUNTIES

IN COLORADO
     NORTHEASTERN JEFFERSON...EXTREME NORTHERN DOUGLAS...WESTERN
     ARAPAHOE...DENVER AND WESTERN ADAMS

INCLUDING...BUT NOT LIMITED TO THE FOLLOWING LOCATIONS
     ARVADA...AURORA...EXTREME SOUTH CENTRAL BROOMFIELD...CHERRY
     HILLS VILLAGE...COMMERCE CITY...DENVER...WESTERN DENVER
     INTERNATIONAL AIRPORT...ENGLEWOOD...LAKEWOOD...LITTLETON...
     NORTHGLENN...THORNTON...WESTMINSTER...WHEAT RIDGE...ACRES
     GREEN...BARR LAKE...CHATFIELD RESERVOIR...EDGEWATER...FEDERAL
     HEIGHTS...GRANDVIEW ESTATES...GREENWOOD VILLAGE...HIGHLANDS
     RANCH...LEYDEN...MOUNTAIN VIEW...PARKER...SHERIDAN AND STONEGATE

AT 331 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
RAPIDLY DEVELOPING THUNDERSTORMS ACROSS THE DENVER METRO AREA.
RAINFALL AMOUNTS OF A HALF INCH TO THREE QUARTERS OF AN INCH WERE
INDICATED IN THE CHERRY HILLS AREA.

STORMS IN THE METRO AREA WILL BE MOVING VERY SLOWLY...AND RAINFALL
AMOUNTS OF 1 TO 1.5 INCHES AN HOUR WILL BE POSSIBLE.

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE LOCAL FLOODING OF
HIGHWAYS...ROADS...AND UNDERPASSES.  ANYONE DRIVING AROUND THE METRO
AREA SHOULD BE PREPARED FOR LOCAL FLOODINGx.  DO NOT ATTEMPT TO DRIVE
THROUGH FLOODED INTERSECTIONS OR UNDERPASSES.  YOU CAN EASILY LOSE
CONTROL OF YOUR VEHICLE.

RTG

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.