Alert archive / Colorado / Flash Flood Warnings in 1998
Flash Flood Warning 23, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this flash flood warning at Jul 31, 1998, 5:50 PM MDT for Douglas County, Colorado. It was in force for 85 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 31, 1998, 5:50 PM MDT (23:50 UTC)
- Expired
- Jul 31, 1998, 7:15 PM MDT
- In force
- 85 min
- Issued by
- NWS Denver/Boulder, CO
- Area
- Whole counties; the outline is the Mesonet’s reconstruction
County Douglas County, CO
The radar
The Denver radar (KFTG), 61 km from the middle of the area, began a volume at 23:50 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, 11.8 hours before the alert went out and 166 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
- 54 J/kg
- Mixed-layer CIN
- -239 J/kg
- Mixed-layer LCL
- 728 m above ground
- 0-6 km bulk shear
- 23 kt
- 0-1 km storm-relative helicity
- 47 m²/s²
- 0-3 km storm-relative helicity
- 105 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 010006
FFWDEN
COC035-010115-
BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DENVER CO
550 PM MDT FRI JUL 31 1998
THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A
* FLASH FLOOD WARNING FOR...
WEST CENTRAL DOUGLAS COUNTY IN NORTHEAST COLORADO
* UNTIL 715 PM MDT
* AT 550 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
VERY HEAVY RAIN 5 MILES EAST OF SPRUCEWOOD...OR ABOUT 28 MILES
SOUTH OF DENVER...MOVING EAST AT 15 MILES PER HOUR.
LOCATIONS IN THE WARNING INCLUDE...LOUVIERS...PERRY PARK...ROXBOROUGH
PARK...SEDALIA AND SPRUCEWOOD
RADAR INDICATED 2.5 TO 3.0 INCHES OF RAIN HAVE FALLEN IN THE PAST
ONE HOUR OVER SPRUCEWOOD AND AREAS WEST TO THE JEFFERSON COUNTY
BORDER.
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.
EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF CREEKS
AND STREAMS...ROADS AND ROADSIDE CULVERTS. THE HEAVY RAINS COULD ALSO
TRIGGER ROCK AND MUDSLIDES IN STEEP TERRAIN.
LAT...LON 3947 10501 3946 10509 3942 10511 3939 10515
3936 10515 3930 10517 3926 10502 3926 10493
3933 10487 3943 10493
RJKWhat 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 31, 4:29 PM MDT, 1 hour 21 minutes before
COZ036-312300- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DENVER CO 429 PM MDT FRI JUL 31 1998 ...THUNDERSTORMS DEVELOPING RAPIDLY NEAR BUFFALO CREEK IN SOUTHERN JEFFERSON COUNTY... AT 423 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR SHOWED RAPIDLY DEVELOPING THUNDERSTORMS 3 MILES SOUTHWEST OF BUFFALO CREEK. THESE STORMS MAY PRODUCE UP TO 1 1/2 INCHES OF RAIN IN 45 MINUTES AS THEY PASS OVER THE BUFFALO CREEK AREA. THOSE LIVING IN AND NEAR BUFFALO CREEK SHOULD BE PREPARED FOR RAPIDLY RISING WATER ALONG BUFFALO CREEK AS THE STORMS MOVE ACROSS THE REGION IN THE NEXT 45 MINUTES. KLEYLA
Special weather statement, Jul 31, 4:29 PM MDT, 1 hour 21 minutes before
COZ036-312300- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DENVER CO 429 PM MDT FRI JUL 31 1998 ...THUNDERSTORMS DEVELOPING RAPIDLY NEAR BUFFALO CREEK IN SOUTHERN JEFFERSON COUNTY... AT 423 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR SHOWED RAPIDLY DEVELOPING THUNDERSTORMS 3 MILES SOUTHWEST OF BUFFALO CREEK. THESE STORMS MAY PRODUCE UP TO 1 1/2 INCHES OF RAIN IN 45 MINUTES AS THEY PASS OVER THE BUFFALO CREEK AREA. THOSE LIVING IN AND NEAR BUFFALO CREEK SHOULD BE PREPARED FOR RAPIDLY RISING WATER ALONG BUFFALO CREEK AS THE STORMS MOVE ACROSS THE REGION IN THE NEXT 45 MINUTES. KLEYLA
The office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 30, 6:00 PM MDT | Flash Flood Warning | BOU | Lincoln | 45 min |
| Jul 30, 6:00 PM MDT | Severe Thunderstorm Warning | BOU | Lincoln | 45 min |
| Jul 30, 7:27 PM MDT | Flash Flood Warning | BOU | Lincoln | 93 min |
| Jul 30, 8:56 PM MDT | Flash Flood Warning | BOU | Lincoln | 2 hr |
| Jul 31, 3:15 PM MDT | Flash Flood Warning | BOU | Clear Creek, Gilpin, Jefferson | 60 min |
| Jul 31, 3:15 PM MDT | Severe Thunderstorm Warning | BOU | Clear Creek, Gilpin, Jefferson | 60 min |
| Jul 31, 5:05 PM MDT | Flash Flood Warning | BOU | Jefferson | 85 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.