Alert archive / Colorado / Flash Flood Warnings in 1998
Flash Flood Warning 30, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this flash flood warning at Aug 9, 1998, 4:33 PM MDT for Adams County, Morgan County, Colorado. It was in force for 117 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
- Aug 9, 1998, 4:33 PM MDT (22:33 UTC)
- Expired
- Aug 9, 1998, 6:30 PM MDT
- In force
- 117 min
- Issued by
- NWS Denver/Boulder, CO
- Area
- Whole counties; the outline is the Mesonet’s reconstruction
Counties Adams County, CO, Morgan County, CO
The radar
The Denver radar (KFTG), 44 km from the middle of the area, began a volume at 22:29 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, 10.6 hours before the alert went out and 76 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.
- Mixed-layer CAPE
- 13 J/kg
- Mixed-layer CIN
- -340 J/kg
- Mixed-layer LCL
- 2304 m above ground
- 0-6 km bulk shear
- 14 kt
- 0-1 km storm-relative helicity
- 20 m²/s²
- 0-3 km storm-relative helicity
- 11 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000
TTAA00 KDEN 092237
FFWDEN
COC001-087-100030-
BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DENVER CO
433 PM MDT SUN AUG 9 1998
THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A
* FLASH FLOOD WARNING FOR...
NORTH CENTRAL ADAMS COUNTY IN NORTHEAST COLORADO
SOUTHWESTERN MORGAN COUNTY IN NORTHEAST COLORADO
* UNTIL 630 PM MDT
* AT 423 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
VERY HEAVY RAIN 5 MILES SOUTHWEST OF HOYT...OR ABOUT 26 MILES
SOUTHWEST OF FORT MORGAN...MOVING NORTHEAST AT 20 MILES PER HOUR.
LOCATIONS IN THE WARNING INCLUDE...HOYT.
ESTIMATED RAINFALL FROM RADAR INDICATED IN EXCESS OF 3 INCHES OF
RAIN HAVE FALLEN ACROSS NORTH CENTRAL ADAMS COUTY...ABOUT 5 MILES
SOUTHWEST OF HOYT. LOCATIONS AROUND ANTELOPE CREEK SHOULD BE
PREPARED FOR RISING WATERS AND FLOODING CONDITIONS.
EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF SMALL
CREEKS AND STREAMS...COUNTRY ROADS...NORMALLY DRY WASHES AND
ARROYOS...AS WELL AS FARMLAND ALONG THE BANKS OF CREEKS AND STREAMS.
A FLASH FLOOD WARNING MEANS THAT FLOODING IS OCCURRING OR IS
IMMINENT. MOST FLASH FLOOD DEATHS OCCUR IN AUTOMOBILES. DO NOT
ATTEMPT TO CROSS BRIDGES...DIPS...OR OTHER LOW SPOTS IF WATER COVERS
THE ROADWAY. NEVER TRY TO CROSS A FLOWING STREAM...EVEN A SMALL
ONE...ON FOOT. TO ESCAPE RISING WATER MOVE UP TO HIGHER GROUND.
ENTREKIN
LAT...LON 4000 10421 3988 10412 4001 10395 4009 10407What 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 9, 11:15 AM MDT, 5 hours 18 minutes before
COZ030-032>050-100600- SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO NATIONAL WEATHER SERVICE DENVER CO 1115 AM MDT SUN AUG 09 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: MONSOON MOISTURE AROUND WILL BE PLENTY OF FUEL FOR WIDELY SCATTERED THUNDERSTORMS THIS AFTERNOON AND SCATTERED THUNDERSTORMS THIS EVENING. A WEAK DISTURBANCE ALOFT WILL TRIGGER THE STORMS BUT WEAK STEERING WINDS WILL KEEP THE STORMS NEARLY STATIONARY ALLOWING RAIN TO FALL OVER AREAS FOR EXTENDED PERIODS OF TIME. THUS HEAVY RAIN IS POSSIBLE. A FEW OF THE STORMS MAY PRODUCE HAIL TOO. THE STORMS ARE NOT EXPECTED TO BE SEVERE SO SPOTTER ACTIVATION IS NOT ANTICIPATED. TA
Special weather statement, Aug 9, 11:15 AM MDT, 5 hours 18 minutes before
COZ030-032>050-100600- SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO NATIONAL WEATHER SERVICE DENVER CO 1115 AM MDT SUN AUG 09 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: MONSOON MOISTURE AROUND WILL BE PLENTY OF FUEL FOR WIDELY SCATTERED THUNDERSTORMS THIS AFTERNOON AND SCATTERED THUNDERSTORMS THIS EVENING. A WEAK DISTURBANCE ALOFT WILL TRIGGER THE STORMS BUT WEAK STEERING WINDS WILL KEEP THE STORMS NEARLY STATIONARY ALLOWING RAIN TO FALL OVER AREAS FOR EXTENDED PERIODS OF TIME. THUS HEAVY RAIN IS POSSIBLE. A FEW OF THE STORMS MAY PRODUCE HAIL TOO. THE STORMS ARE NOT EXPECTED TO BE SEVERE SO SPOTTER ACTIVATION IS NOT ANTICIPATED. TA
The office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 8, 6:20 PM MDT | Flash Flood Warning | BOU | Morgan | 85 min |
| Aug 8, 6:25 PM MDT | Severe Thunderstorm Warning | BOU | Morgan | 50 min |
| Aug 8, 7:12 PM MDT | Flash Flood Warning | BOU | Morgan | 93 min |
| Aug 8, 8:59 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Arapahoe | 31 min |
| Aug 9, 3:35 AM MDT | Flash Flood Warning | BOU | Lincoln | 3 hr |
| Aug 9, 3:38 AM MDT | Flash Flood Warning | BOU | Lincoln | 3 hr |
| Aug 9, 3:02 PM MDT | Severe Thunderstorm Warning | BOU | Douglas | 43 min |
| Aug 9, 3:32 PM MDT | Severe Thunderstorm Warning | BOU | Douglas, Elbert | 43 min |
| Aug 9, 3:38 PM MDT | Severe Thunderstorm Warning | BOU | Arapahoe, Elbert | 52 min |
| Aug 9, 3:48 PM MDT | Tornado Warning | BOU | Adams | 27 min |
| Aug 9, 3:57 PM MDT | Tornado Warning | BOU | Morgan, Weld | 48 min |
| Aug 9, 4:01 PM MDT | Severe Thunderstorm Warning | BOU | Washington | 44 min |
| Aug 9, 4:43 PM MDT | Tornado Warning | BOU | Adams, Morgan, Weld | 32 min |
| Aug 9, 4:49 PM MDT | Flash Flood Warning | BOU | Washington | 86 min |
| Aug 9, 4:52 PM MDT | Severe Thunderstorm Warning | BOU | Lincoln, Washington | 38 min |
| Aug 9, 5:21 PM MDT | Flash Flood Warning | BOU | Lincoln, Washington | 99 min |
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; radar from the NEXRAD Level II archive.