Alert archive / Colorado / Flash Flood Warnings in 2001

Flash Flood Warning 10, NWS Denver/Boulder, CO

July 11, 2001Weld County, Colorado

NWS Denver/Boulder, CO issued this flash flood warning at Jul 11, 2001, 9:38 PM MDT for Weld County, Colorado. It was in force for 97 min. 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 11, 2001, 9:38 PM MDT (03:38 UTC)
Expired
Jul 11, 2001, 11:15 PM MDT
In force
97 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Weld County, CO

The nearest sounding before it

Denver, CO (KDNR), launched 00:00Z, 3.6 hours before the alert went out and 164 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 2001-07-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 48 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 2001-07-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 34 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
48 J/kg
Mixed-layer CIN
-46 J/kg
Mixed-layer LCL
2926 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
34 m²/s²
0-3 km storm-relative helicity
92 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 
WGUS55 KBOU 120342
FFWBOU
COC123-120515-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DENVER CO
938 PM MDT WED JUL 11 2001

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  WEST CENTRAL WELD COUNTY IN NORTHEAST COLORADO

* UNTIL 1115 PM MDT

* AT 938 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAIN OVER WEST CENTRAL WELD COUNTY...OR ABOUT 25 MILES
  NORTH OF GREELEY. THE STORMS PRODUCING THE HEAVY RAIN WERE
  MOVING EAST AT 5 TO 10 MPH.  RADAR ESTIMATES 4 TO 5 INCHES OF RAIN
  HAS FALLEN JUST NORTHEAST OF NUNN OVER THE 90 MINUTES.

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 NORTHEAST OF NUNN ALONG LITTLE OWL CREEK...ROBINSON
CREEK AND EASTMAN CREEK 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.

LAT...LON 4082 10487 4070 10486 4071 10460 4083 10460

KLEYLA


3

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 11, 6:25 PM MDTSevere Thunderstorm WarningBOUBoulder35 min
Jul 11, 6:27 PM MDTSevere Thunderstorm WarningBOUWeld33 min

Nearby

Flash Flood Warnings in Colorado, 2001Every flash flood warning in 2001

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.