Alert archive / Colorado / Flash Flood Warnings in 1997

Flash Flood Warning 9, NWS Grand Junction, CO

August 5, 1997Garfield County, Colorado

NWS Grand Junction, CO issued this flash flood warning at Aug 5, 1997, 10:24 PM MDT for Garfield County, Colorado. It was in force for 3 hr. 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 5, 1997, 10:24 PM MDT (04:24 UTC)
Expired
Aug 6, 1997, 1:15 AM MDT
In force
3 hr
Issued by
NWS Grand Junction, CO
Area
Whole counties

County Garfield County, CO

The radar

The Grand Junction radar (KGJX), 65 km from the middle of the area, began a volume at 04:25 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

Grand Junction, CO (KGJT), launched 00:00Z, 4.4 hours before the alert went out and 73 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, Grand Junction, CO at 00:00Z on 1997-08-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1119 joules per kilogram.LCLEL10008507005003002001001 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, Grand Junction, CO at 00:00Z on 1997-08-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 8 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
1119 J/kg
Mixed-layer CIN
-16 J/kg
Mixed-layer LCL
1369 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
8 m²/s²
0-3 km storm-relative helicity
-15 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 KGJT 060429 COR
FFWGJT
COC045-060715-

BULLETIN - EAS ACTIVATION/IMMEDIATE BROADCAST REQUESTED
FLASH FLOOD WARNING...CORRECTED
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1024 PM MDT TUE AUG 5 1997

* FLASH FLOOD WARNING FOR
  CENTRAL GARFIELD COUNTY COLORADO - NORTHWEST COLORADO

* UNTIL 115 AM MDT
 
* SOME LOCATIONS/STREAMS AFFECTED
  GOVERNMENT CREEK...RIFLE CREEK AND DRAINAGES IN AND AROUND RIO
  BLANCO.

* LOCALLY HEAVY RAINS HAVE CAUSED RAPID RISES IN GOVERNMENT CREEK
AND RIFLE CREEK AS REPORTED BY THE RIFLE POLICE DEPARTMENT.
WATER HAS ALSO BEEN REPORTED OVER SOME ROADWAYS IN THE RIO
BLANCO AREA.

* LOCALLY HEAVY RAINS ARE EXPECTED TO CONTINUE FOR THE NEXT FEW
HOURS AS THE GRAND JUNCTION RADAR SHOWS REDEVELOPMENT OF
THUNDERSTORMS TO THE WEST MOVING EAST AT 20 MPH.

LEAVE FLOOD PRONE OR LOW LYING AREAS IMMEDIATELY.

MC

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.

NWS Grand Junction, CO wrote its last area forecast discussion before this flash flood warning went out at Aug 5, 1:31 PM MDT, 8 hours 53 minutes earlier.

Area forecast discussion, Aug 5, 1:31 PM MDT, 8 hours 53 minutes before
COZ001>012-014-015-017>023-UTZ023>027-060730-

WESTERN COLORADO & EASTERN UTAH AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
128 PM MDT TUE AUG 5 1997

IT IS A CONFUSING WEATHER SITUATION IN MY OPINION.  BASED ON SATELLITE
MOVEMENTS...ALL MODELS SEEMED TO BE CORRECT YESTERDAY IN TAKING THE LOW
NORTHWARD INTO EASTERN IDAHO AND SOUTHWEST MONTANA.  THEY ALL THEN MOVED
THE LOW TO THE SOUTHEAST WITH A BIG ASSOCIATED VORTICITY AREA MOVING
INTO WESTERN WY BY THIS EVENING.  THAT TREND STILL REMAINS ON THE LATEST
MODEL RUNS AND LOOKS OK.  AT THE SAME TIME...THEY KEPT LOTS OF MOISTURE
AROUND ESPECIALLY OVER THE NORTHERN PORTION OF THE CWA ALTHOUGH SOME
DRYING IS INDICATED. SATELLITE...HOWEVER...IS ALREADY SHOWING GOOD
DRYING OVER MOST OF UTAH MOVING INTO OUR AREA.  GRANTED THE MOISTURE
SEEN ON SATELLITE IN THE SALT LAKE CITY AREA DOES CORRESPOND WITH VORT
LOBE/TROUGH SEEN ON MODELS. THIS SHOULD ARRIVE IN NORTHWEST CO/NORTHEAST
UT EARLY THIS EVENING AND COULD BE ENOUGH TO KICK OFF SOME HEAVY RAIN SO
EXPECT THE FFA SHOULD CONTINUE THIS EVENING.

CONFUSION COMES WITH THE 24 HOUR PATTERN.  THE MODELS BRING THE LOW INTO
NORTHEAST CO...AS I WOULD EXPECT GIVEN THE 300 MB FLOW...BUT THEY MOVE
THE MAJOR VORT LOBE ASSOCIATED WITH THIS ALMOST STRAIGHT SOUTH.  THIS
DOES NOT MAKE SENSE TO ME.

BOTTOM LINE...I EXPECT QUITE A BIT OF DRYING TONIGHT AND WED OVER MOST
OF OUR CWA MAINLY TO THE SOUTH OF THE TAVAPUTS PLATEAU (ZONE 3) WITH
CONVECTION BUILDING UP DURING THE DAY MAINLY OVER THE MOUNTAINS AND
TEMPS A BIT CLOSER TO NORMALS.  SOME EXTRA MOISTURE IS LIKELY TO REMAIN
OVER THE NORTHERN SECTION SO A BIT MORE CLOUDINESS IS LIKELY BUT STILL
EXPECT GENERALLY PARTLY CLOUDY MORNINGS.

RWJJ

The office that day

Everything else NWS Grand Junction, CO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 6, 1:23 PM MDTFlash Flood WarningGJTGarfield3 hr

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.