Alert archive / Colorado / Flash Flood Warnings in 1998
Flash Flood Warning 3, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this flash flood warning at Jul 23, 1998, 5:11 PM MDT for Adams County, Arapahoe County, Colorado. It was in force for 2 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 23, 1998, 5:11 PM MDT (23:11 UTC)
- Expired
- Jul 23, 1998, 7:15 PM MDT
- In force
- 2 hr
- Issued by
- NWS Denver/Boulder, CO
- Area
- Whole counties; the outline is the Mesonet’s reconstruction
Counties Adams County, CO, Arapahoe County, CO
The radar
The Denver radar (KFTG), 58 km from the middle of the area, began a volume at 23:10 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, 11.2 hours before the alert went out and 56 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
- 81 J/kg
- Mixed-layer CIN
- -228 J/kg
- Mixed-layer LCL
- 1157 m above ground
- 0-6 km bulk shear
- 11 kt
- 0-1 km storm-relative helicity
- 76 m²/s²
- 0-3 km storm-relative helicity
- 85 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 232316
FFWDEN
COC001-005-240115-
BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DENVER CO
511 PM MDT THU JUL 23 1998
THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A
* FLASH FLOOD WARNING FOR...
SOUTHEASTERN ADAMS COUNTY IN NORTHEAST COLORADO
EASTERN ARAPAHOE COUNTY IN NORTHEAST COLORADO
* UNTIL 715 PM MDT
* AT 504 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
VERY HEAVY RAIN CONTINUES OVER EXTREME SOUTHEAST ADAMS AND
EASTERN ARAPAHOE COUNTIES. RADAR ESTIMATES THAT UP TO 5 INCHES OF
RAIN HAS OCCURRED IN THE PAST 90 MINUTES IN THESE AREAS.
LOCATIONS IN THE WARNING INCLUDE...JOLLY RANCH
RESIDENTS IN JOLLY RANCH AND ALONG BADGER CREEK SHOULD BE PREPARED
FOR EXCESSIVE RUNOFF WHICH 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.
LAT...LON 3988 10394 3958 10398 3957 10375 3989 10373
KLEYLAWhat 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 23, 12:08 PM MDT, 5 hours 3 minutes before
COZ030-032>050-240600- SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO NATIONAL WEATHER SERVICE DENVER CO 1208 PM MDT THU JUL 23 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 ...FLASH FLOOD WATCH UNTIL MIDNIGHT TONIGHT FOR SOUTHEAST ELBERT AND LINCOLN COUNTIES... SYNOPSIS: THE ATMOSPHERE REMAINS QUITE MOIST AS INDICATED BY HIGHER HUMIDITIES AND THE WIDESPREAD CLOUD COVER. CHANCES FOR RAINFALL LOOK GOOD THIS AFTERNOON AND EVENING ACROSS THE OUTLOOK AREA. HOWEVER A NUMBER OF FACTORS POINT TO NOT AS HEAVY OR AS WIDESPREAD RAINFALL TODAY. FIRST IS A LACK OF FAVORABLE EAST-NORTHEASTERLY UPSLOPE FLOW. SECOND IS THE LACK OF STRONG HEATING DUE TO THE HEAVY CLOUD COVER. AND THIRD IS THE LACK OF AN UPPER LEVEL WEATHER DISTURBANCE OR COLD FRONT TO FOCUS THUNDERSTORM ACTIVITY SUCH WAS THE CASE YESTERDAY. INITIAL SHOWER ACTIVITY EARLY THIS AFTERNOON WILL BE LIGHT AND SCATTERED IN COVERAGE. RAINFALL AMOUNTS WITH THESE SHOWERS WILL BE LESS THAN A QUARTER INCH. BY LATE THIS AFTERNOON THUNDERSTORMS FORMING OVER THE MOUNTAINS ARE EXPECTED TO MOVE SLOWLY NORTHEAST ONTO THE PLAINS. THUNDERSTORMS WILL BE SLOW MOVERS...AGAIN WITH SOME STORMS CAPABLE OF HEAVY RAIN. RAINFALL RATES FROM STORMS MOVING ACROSS THE FRONT RANGE URBAN CORRIDOR SHOULD RANGE FROM A TENTH TO ONE-HALF INCH...WITH SPOTTY RAINFALL RATES UP TO 1.5 INCHES. HEAVIEST RAINFALL SHOULD FALL ACROSS DOUGLAS...SOUTHERN JEFFERSON...ARAPAHOE AND SOUTHERN ELBERT AND SOUTHERN LINCOLN COUNTIES. SOILS IN THESE AREAS ARE ALREADY VERY WET FROM EARLIER RAINFALL. THUS LOCAL FLOODING OF LOW LYING AREAS AND SMALL STREAMS IS POSSIBLE IN THESE COUNTIES AFTER 4 PM MDT. SKYWARN STORM SPOTTERS ARE ASK TO RELAY ANY HEAVY RAIN OR FLOODING REPORTS TO THE NATIONAL WEATHER SERVICE IN DENVER. BAKER
Special weather statement, Jul 23, 12:08 PM MDT, 5 hours 3 minutes before
COZ030-032>050-240600- SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO NATIONAL WEATHER SERVICE DENVER CO 1208 PM MDT THU JUL 23 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 ...FLASH FLOOD WATCH UNTIL MIDNIGHT TONIGHT FOR SOUTHEAST ELBERT AND LINCOLN COUNTIES... SYNOPSIS: THE ATMOSPHERE REMAINS QUITE MOIST AS INDICATED BY HIGHER HUMIDITIES AND THE WIDESPREAD CLOUD COVER. CHANCES FOR RAINFALL LOOK GOOD THIS AFTERNOON AND EVENING ACROSS THE OUTLOOK AREA. HOWEVER A NUMBER OF FACTORS POINT TO NOT AS HEAVY OR AS WIDESPREAD RAINFALL TODAY. FIRST IS A LACK OF FAVORABLE EAST-NORTHEASTERLY UPSLOPE FLOW. SECOND IS THE LACK OF STRONG HEATING DUE TO THE HEAVY CLOUD COVER. AND THIRD IS THE LACK OF AN UPPER LEVEL WEATHER DISTURBANCE OR COLD FRONT TO FOCUS THUNDERSTORM ACTIVITY SUCH WAS THE CASE YESTERDAY. INITIAL SHOWER ACTIVITY EARLY THIS AFTERNOON WILL BE LIGHT AND SCATTERED IN COVERAGE. RAINFALL AMOUNTS WITH THESE SHOWERS WILL BE LESS THAN A QUARTER INCH. BY LATE THIS AFTERNOON THUNDERSTORMS FORMING OVER THE MOUNTAINS ARE EXPECTED TO MOVE SLOWLY NORTHEAST ONTO THE PLAINS. THUNDERSTORMS WILL BE SLOW MOVERS...AGAIN WITH SOME STORMS CAPABLE OF HEAVY RAIN. RAINFALL RATES FROM STORMS MOVING ACROSS THE FRONT RANGE URBAN CORRIDOR SHOULD RANGE FROM A TENTH TO ONE-HALF INCH...WITH SPOTTY RAINFALL RATES UP TO 1.5 INCHES. HEAVIEST RAINFALL SHOULD FALL ACROSS DOUGLAS...SOUTHERN JEFFERSON...ARAPAHOE AND SOUTHERN ELBERT AND SOUTHERN LINCOLN COUNTIES. SOILS IN THESE AREAS ARE ALREADY VERY WET FROM EARLIER RAINFALL. THUS LOCAL FLOODING OF LOW LYING AREAS AND SMALL STREAMS IS POSSIBLE IN THESE COUNTIES AFTER 4 PM MDT. SKYWARN STORM SPOTTERS ARE ASK TO RELAY ANY HEAVY RAIN OR FLOODING REPORTS TO THE NATIONAL WEATHER SERVICE IN DENVER. BAKER
Special weather statement, Jul 23, 2:57 PM MDT, 2 hours 14 minutes before
COZ067-232130- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DENVER CO 257 PM MDT THU JUL 23 1998 ...THUNDERSTORMS INCREASING OVER SOUTHWESTERN DOUGLAS COUNTY... AT 250 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A THUNDERSTORM OVER WESTCREEK...OR ABOUT 27 MILES NORTHWEST OF COLORADO SPRINGS...MOVING EAST AT 10 MILES PER HOUR. THIS STORM WILL PRODUCE VERY HEAVY RAIN UP TO 2 INCHES PER HOUR ALONG WITH DANGEROUS LIGHTNING. PERSONS IN OR NEAR DEVIL'S HEAD...PERRY PARK AND WESTCREEK SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER AND MOVE TO A PLACE OF SAFETY IF BAD WEATHER APPROACHES. HEAVY RAINS MAY FLOOD LOW LYING AREAS SUCH AS DITCHES AND UNDERPASSES. AVOID T4HESE AREAS AND DO NOT CROSS FLOODED ROADS AS THEY MAY BE WASHED OUT. WATER LEVELS OF SMALL STREAMS AND RIVERS MAY ALSO RISE...THEREFORE SEEK HIGHER GROUND IF THREATENED BY FLOOD WATERS. KLEYLA
Special weather statement, Jul 23, 2:57 PM MDT, 2 hours 14 minutes before
COZ067-232130- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DENVER CO 257 PM MDT THU JUL 23 1998 ...THUNDERSTORMS INCREASING OVER SOUTHWESTERN DOUGLAS COUNTY... AT 250 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A THUNDERSTORM OVER WESTCREEK...OR ABOUT 27 MILES NORTHWEST OF COLORADO SPRINGS...MOVING EAST AT 10 MILES PER HOUR. THIS STORM WILL PRODUCE VERY HEAVY RAIN UP TO 2 INCHES PER HOUR ALONG WITH DANGEROUS LIGHTNING. PERSONS IN OR NEAR DEVIL'S HEAD...PERRY PARK AND WESTCREEK SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER AND MOVE TO A PLACE OF SAFETY IF BAD WEATHER APPROACHES. HEAVY RAINS MAY FLOOD LOW LYING AREAS SUCH AS DITCHES AND UNDERPASSES. AVOID T4HESE AREAS AND DO NOT CROSS FLOODED ROADS AS THEY MAY BE WASHED OUT. WATER LEVELS OF SMALL STREAMS AND RIVERS MAY ALSO RISE...THEREFORE SEEK HIGHER GROUND IF THREATENED BY FLOOD WATERS. KLEYLA
The office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 23, 4:08 PM MDT | Tornado Warning | BOU | Adams, Arapahoe | 37 min |
| Jul 23, 4:12 PM MDT | Tornado Warning | BOU | Washington | 33 min |
| Jul 23, 4:23 PM MDT | Tornado Warning | BOU | Adams, Arapahoe | 22 min |
| Jul 23, 4:41 PM MDT | Tornado Warning | BOU | Morgan, Washington | 34 min |
| Jul 23, 5:12 PM MDT | Flash Flood Warning | BOU | Morgan, Washington | 2 hr |
| Jul 23, 5:47 PM MDT | Tornado Warning | BOU | Washington | 28 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.