Alert archive / Colorado / Flash Flood Warnings in 1998

Flash Flood Warning 14, NWS Denver/Boulder, CO

July 30, 1998Arapahoe County, Douglas County, Colorado

NWS Denver/Boulder, CO issued this flash flood warning at Jul 30, 1998, 3:00 PM MDT for Arapahoe County, Douglas 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 outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties.

The facts

Issued
Jul 30, 1998, 3:00 PM MDT (21:00 UTC)
Expired
Jul 30, 1998, 6:00 PM MDT
In force
3 hr
Issued by
NWS Denver/Boulder, CO
Area
Whole counties; the outline is the Mesonet’s reconstruction

Counties Arapahoe County, CO, Douglas County, CO

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 9.0 hours before the alert went out and 133 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 1998-07-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 61 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 1998-07-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 1 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
61 J/kg
Mixed-layer CIN
-76 J/kg
Mixed-layer LCL
804 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
1 m²/s²
0-3 km storm-relative helicity
13 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 302117 COR
FFWDEN
COC005-035-310000-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING...CORRECTION
NATIONAL WEATHER SERVICE DENVER CO
300 PM MDT THU JUL 30 1998

...CORRECTED TO ADD CASTLE ROCK AND SILVER HEIGHTS IN THE CITIES
LIST...

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

* FLASH FLOOD WARNING FOR...
     SOUTHWESTERN ARAPAHOE COUNTY IN NORTHEAST COLORADO
     NORTHEASTERN DOUGLAS COUNTY IN NORTHEAST COLORADO

* UNTIL 600 PM MDT

* AT 258 PM MDT...THE PUBLIC REPORTED 1.81 INCHES OF RAIN IN PARKER 
IN ONLY 15 MINUTES.  THE STORM WAS MOVING EAST AT 15 MILES PER HOUR.

HIGH WATERS FROM THIS STORM WILL MOVE TOWARDS CHERRY CREEK RESERVOIR.
OTHER STORMS CONTINUE TO REDEVELOP IN DOUGLAS COUNTY AND FLASH 
FLOODING IS LIKELY.

LOCATIONS IN THE WARNING INCLUDE...CASTLE ROCK...ARAPAHOE PARK...
PARKER...THE PINERY...AND SILVER HEIGHTS 

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF SMALL
CREEKS AND STREAMS...HIGHWAYS AND UNDERPASSES. ADDITIONALLY...COUNTRY
ROADS AND FARMLANDS ALONG THE BANKS OF CREEKS AND STREAMS AND OTHER
LOW LYING AREAS ARE SUBJECT TO FLASH FLOODING.

LAT...LON 3961 10488 3937 10483 3945 10468 3956 10465
          3957 10453 3967 10466

COOPER

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, Jul 30, 9:22 AM MDT, 5 hours 38 minutes before
COZ043-301600-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
922 AM MDT THU JUL 30 1998

...FUNNEL CLOUDS REPORTED SOUTH OF GREELEY...

AT 919 AM MDT...THE PUBLIC REPORTED A FUNNEL CLOUD ABOUT 5 MILES
SOUTH OF GREELEY.  THERE WERE ONLY SOME LIGHT RAIN SHOWERS IN THE
AREA...BUT PEOPLE IN THE AREAS BETWEEN LASALLE AND PLATTEVILLE
SHOULD REMAIN ALERT TO WEATHER CONDITIONS.  IF A FUNNEL CLOUD IS
APPROACHING YOUR AREA...TAKE SHELTERN IN A STURDY STRUCTURE AND STAY
AWAY FROM WINDOWS.

BARJENBRUCH
Special weather statement, Jul 30, 9:22 AM MDT, 5 hours 38 minutes before
COZ043-301600-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
922 AM MDT THU JUL 30 1998

...FUNNEL CLOUDS REPORTED SOUTH OF GREELEY...

AT 919 AM MDT...THE PUBLIC REPORTED A FUNNEL CLOUD ABOUT 5 MILES
SOUTH OF GREELEY.  THERE WERE ONLY SOME LIGHT RAIN SHOWERS IN THE
AREA...BUT PEOPLE IN THE AREAS BETWEEN LASALLE AND PLATTEVILLE
SHOULD REMAIN ALERT TO WEATHER CONDITIONS.  IF A FUNNEL CLOUD IS
APPROACHING YOUR AREA...TAKE SHELTERN IN A STURDY STRUCTURE AND STAY
AWAY FROM WINDOWS.

BARJENBRUCH
Special weather statement, Jul 30, 11:10 AM MDT, 3 hours 50 minutes before
COZ030-032>050-310600-

SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO
NATIONAL WEATHER SERVICE DENVER CO
1110 AM MDT THU JUL 30 1998

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:  ABUNDANT MOISTURE WILL REMAIN IN PLACE ACROSS EASTERN
COLORADO THROUGH THIS AFTERNOON AND EVENING.  THE BEST INSTABILITY
WILL BE FOUND IN AND NEAR THE FOOTHILLS WHERE A FEW PEAKS OF
SUNSHINE WILL OCCUR.  ON THE NORTHEAST PLAINS...THE AIRMASS IS
QUITE STABLE AS LOW LEVEL COOL AIR HAS SPREAD IN BEHIND A SURFACE
FRONT.

AS DAYTIME HEATING REACTS WITH THE MOISTURE IN AND NEAR THE
FOOTHILLS...THUNDERSTORMS WILL BE DEVELOPING BY 1 PM.  AN UPPER
LEVEL DISTURBANCE MOVING TOWARD WESTERN COLORADO NOW WILL ALSO BE
APPROACHING BY LATE THIS AFTERNOON TO HELP SPARK THE DEVELOPMENT OF
STORMS.  WITH ABUNDANT MOISTURE IN PLACE...LOCALLY HEAVY RAINFALL
WILL OCCUR IN AND NEAR THE FOOTHILLS.  THIS WOULD INCLUDE THE FRONT
RANGE FROM CASTLE ROCK AND DENVER NORTHWARD THROUGH FORT COLLINS.

SEVERE STORMS AND LARGE HAIL WILL NOT BE A THREAT TODAY GIVEN THE
CLOUD COVER AND LIMITED INSTABILITY.  HOWEVER...BE ON THE LOOKOUT
FOR HEAVY RAINFALL.  RAINFALL RATES WITH THE STRONGER STORMS MAY
EXCEED 2 INCHES PER HOUR.  A FLASH FLOOD WATCH MAY BE REQUIRED FOR
THE FOOTHILLS AND FRONT RANGE CITIES LATER THIS AFTERNOON.

SPOTTER ACTIVATION FOR SEVERE WEATHER WILL NOT BE REQUIRED TODAY.
HOWEVER...ANY REPORTS OF HEAVY RAINFAVLL WOULD BE GREATLY
APPRECIATED.

BARJENBRUCH
Special weather statement, Jul 30, 11:10 AM MDT, 3 hours 50 minutes before
COZ030-032>050-310600-

SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO
NATIONAL WEATHER SERVICE DENVER CO
1110 AM MDT THU JUL 30 1998

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:  ABUNDANT MOISTURE WILL REMAIN IN PLACE ACROSS EASTERN
COLORADO THROUGH THIS AFTERNOON AND EVENING.  THE BEST INSTABILITY
WILL BE FOUND IN AND NEAR THE FOOTHILLS WHERE A FEW PEAKS OF
SUNSHINE WILL OCCUR.  ON THE NORTHEAST PLAINS...THE AIRMASS IS
QUITE STABLE AS LOW LEVEL COOL AIR HAS SPREAD IN BEHIND A SURFACE
FRONT.

AS DAYTIME HEATING REACTS WITH THE MOISTURE IN AND NEAR THE
FOOTHILLS...THUNDERSTORMS WILL BE DEVELOPING BY 1 PM.  AN UPPER
LEVEL DISTURBANCE MOVING TOWARD WESTERN COLORADO NOW WILL ALSO BE
APPROACHING BY LATE THIS AFTERNOON TO HELP SPARK THE DEVELOPMENT OF
STORMS.  WITH ABUNDANT MOISTURE IN PLACE...LOCALLY HEAVY RAINFALL
WILL OCCUR IN AND NEAR THE FOOTHILLS.  THIS WOULD INCLUDE THE FRONT
RANGE FROM CASTLE ROCK AND DENVER NORTHWARD THROUGH FORT COLLINS.

SEVERE STORMS AND LARGE HAIL WILL NOT BE A THREAT TODAY GIVEN THE
CLOUD COVER AND LIMITED INSTABILITY.  HOWEVER...BE ON THE LOOKOUT
FOR HEAVY RAINFALL.  RAINFALL RATES WITH THE STRONGER STORMS MAY
EXCEED 2 INCHES PER HOUR.  A FLASH FLOOD WATCH MAY BE REQUIRED FOR
THE FOOTHILLS AND FRONT RANGE CITIES LATER THIS AFTERNOON.

SPOTTER ACTIVATION FOR SEVERE WEATHER WILL NOT BE REQUIRED TODAY.
HOWEVER...ANY REPORTS OF HEAVY RAINFAVLL WOULD BE GREATLY
APPRECIATED.

BARJENBRUCH

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 29, 6:01 PM MDTSevere Thunderstorm WarningBOUArapahoe, Elbert29 min
Jul 29, 6:32 PM MDTSevere Thunderstorm WarningBOUElbert, Lincoln43 min
Jul 29, 7:13 PM MDTSevere Thunderstorm WarningBOULincoln32 min
Jul 29, 7:39 PM MDTSevere Thunderstorm WarningBOULincoln36 min
Jul 30, 1:41 PM MDTSevere Thunderstorm WarningBOUDouglas, Jefferson, Park34 min
Jul 30, 4:22 PM MDTFlash Flood WarningBOUElbert, Lincoln2 hr
Jul 30, 4:24 PM MDTSevere Thunderstorm WarningBOULincoln51 min
Jul 30, 5:00 PM MDTFlash Flood WarningBOUPark2 hr
Jul 30, 5:14 PM MDTSevere Thunderstorm WarningBOULincoln46 min
Jul 30, 5:25 PM MDTFlash Flood WarningBOUElbert, Lincoln2 hr

Nearby

Flash Flood Warnings in Colorado, 1998Every flash flood warning in 1998

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.