Alert archive / Colorado / Flash Flood Warnings in 2004

Flash Flood Warning 22, NWS Denver/Boulder, CO

July 23, 2004Adams County, Colorado

NWS Denver/Boulder, CO issued this flash flood warning at Jul 23, 2004, 2:47 PM MDT for Adams 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 outline as issued.

The facts

Issued: Jul 23, 2004, 2:47 PM MDT (20:47 UTC)
Expired: Jul 23, 2004, 4:45 PM MDT
In force: 118 min
Issued by: NWS Denver/Boulder, CO
Area: Counties, with a storm outline in the text

County Adams County, CO

The radar

The Denver radar (KFTG), 38 km from the middle of the area, began a volume at 20:48 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, 8.8 hours before the alert went out and 149 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 110 J/kg
Mixed-layer CIN: -21 J/kg
Mixed-layer LCL: 600 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: 55 m²/s²
0-3 km storm-relative helicity: 137 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

The text

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

000 
WGUS55 KBOU 232050
FFWBOU
COC001-232245-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DENVER CO
247 PM MDT FRI JUL 23 2004

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EXTREME WESTERN ADAMS COUNTY IN NORTHEAST COLORADO

* UNTIL 445 PM MDT

* AT 247 PM MDT...THE ADAMS COUNTY SHERIFF REPORTED A FLASH FLOOD IN 
SEVERAL AREAS OF THORNTON.  WATER WAS REPORTED 3 TO 4 FEET DEEP AT 
84TH AND GRANT...NEAR CONIFER AND HURON...AND 102ND AND MELODY.  

A FLASH FLOOD WARNING MEANS THAT FLOODING IS 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 SWIFTLY FLOWING 
WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY AUTOMOBILE. IF YOUR 
VEHICLE STALLS ABANDON IT IMMEDIATELY AND SEEK HIGHER GROUND.

DOPPLER RADAR AND AUTOMATED RAIN GAUGES ESTIMATES THAT ABOUT 2 
INCHES OF RAIN FELL IN A 45 MINUTE PERIOD THIS AFTERNOON.  

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF SMALL
CREEKS AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND UNDERPASSES
AS WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS.

LAT...LON 3991 10505 3986 10505 3981 10491 3984 10484

$$

BARJENBRUCH

2 follow-up statements

000 
WGUS75 KBOU 232154
FFSBOU
COC001-232245-

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
353 PM MDT FRI JUL 23 2004

...A FLASH FLOOD WARNING REMAINS IN EFFECT FOR EXTREME WESTERN ADAMS 
COUNTY UNTIL 445 PM MDT...

FLOODING OF LOW LYING ROADS AND INTERSECTIONS CONTINUED OVER A GOOD 
PORTIONS OF WESTERN ADAMS COUNTY LATE THIS AFTERNOON.  THE ADAMS 
COUNTY SHERIFF REPORTED MOST FLOODING...INCLUDING FLOODED 
BASEMENTS...WAS OCCURRING WEST OF COLORADO BOULEVARD.  
HOWEVER...THE WATERS WERE BEGINNING TO RECEDE.  

UNTIL THE HIGH WATERS RECEDE...DO NOT DRIVE THROUGH FLOODED AREAS.  
THE WATER MAY BE TOO DEEP TO ALLOW YOUR CAR TO CROSS SAFELY.  
IF YOUR VEHICLE IS CAUGHT OR STALLS IN HIGH WATER...ABANDON IT 
IMMEDIATELY AND SEEK HIGHER GROUND.

DOPPLER RADAR AND AUTOMATED RAIN GAUGES ESTIMATES THAT ABOUT 2 
INCHES OF RAIN FELL IN A 45 MINUTE PERIOD THIS AFTERNOON.  

LAT...LON 3991 10505 3986 10505 3981 10491 3984 10484

$$

BARJENBRUCH

000 
WGUS75 KBOU 232245
FFSBOU
COC001-232310-

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
445 PM MDT FRI JUL 23 2004

...THE FLASH FLOOD WARNING FOR EXTREME WESTERN ADAMS COUNTY HAS 
EXPIRED...

THE ADAMS COUNTY SHERIFF REPORTED THAT FLOOD WATERS HAVE RECEDED 
ACROSS WESTERN ADAMS COUNTY INCLUDING THE GREATER THORNTON AREA.  

ANOTHER STORM WITH A PERIOD OF HEAVY RAIN WILL MOVE ACROSS WESTERN 
ADAMS COUNTY BETWEEN 4 AND 430 PM...SO ADDITIONAL FLOODING MAY 
DEVELOP.  STAY TUNED TO THE NATIONAL WEATHER SERVICE FOR LATER 
STATEMENTS AND POSSIBLE WARNINGS.

LAT...LON 3991 10505 3986 10505 3981 10491 3984 10484

$$

BARJENBRUCH

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 23, 3:22 PM MDT	Flash Flood Warning	BOU	Arapahoe	3 hr
Jul 23, 4:05 PM MDT	Flash Flood Warning	BOU	Douglas, Jefferson	3 hr
Jul 23, 5:17 PM MDT	Flash Flood Warning	BOU	Park	3 hr

Nearby

Flash Flood Warnings in Colorado, 2004 Every flash flood warning in 2004

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.