Alert archive / Colorado / Flash Flood Warnings in 1998
Flash Flood Warning 2, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this flash flood warning at Jul 21, 1998, 7:57 PM MDT for Logan 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 21, 1998, 7:57 PM MDT (01:57 UTC)
- Expired
- Jul 21, 1998, 11:00 PM MDT
- In force
- 3 hr
- Issued by
- NWS Denver/Boulder, CO
- Area
- Whole counties; the outline is the Mesonet’s reconstruction
County Logan County, CO
The radar
The Denver radar (KFTG), 162 km from the middle of the area, began a volume at 02:01 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 00:00Z, 2.0 hours before the alert went out and 81 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
- 116 J/kg
- Mixed-layer CIN
- -226 J/kg
- Mixed-layer LCL
- 2387 m above ground
- 0-6 km bulk shear
- 25 kt
- 0-1 km storm-relative helicity
- -12 m²/s²
- 0-3 km storm-relative helicity
- 132 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.6
The text
As transmitted, in the capitals the NWS used until 2016.
000
TTAA00 KDEN 220158
FFWDEN
COC075-220500-
BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DENVER CO
757 PM MDT TUE JUL 21 1998
THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A
* FLASH FLOOD WARNING FOR...
SOUTHEASTERN LOGAN COUNTY IN NORTHEAST COLORADO
* UNTIL 1100 PM MDT
* AT 750 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
VERY HEAVY RAIN CONTINUING OVER SOUTHEAST LOGAN COUNTY. RADAR
ESTIMATES THAT UP TO 3 INCHES OF RAIN HAS OCCURRED IN THE PAST
HOUR OVER SOUTHEAST LOGAN COUNTY.
LOCATIONS IN THE WARNING INCLUDE...ST PETERSBURG
A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY
AUTOMOBILE. IF YOUR VEHICLE STALLS, ABANDON IT IMMEDIATELY AND SEEK
HIGHER GROUND.
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 AN,D STREAMS.
LAT...LON 4065 10311 4044 10312 4044 10268 4065 10268
KLEYLAThe office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 21, 6:03 PM MDT | Severe Thunderstorm Warning | BOU | Logan | 42 min |
| Jul 21, 6:22 PM MDT | Severe Thunderstorm Warning | BOU | Morgan, Washington | 38 min |
| Jul 21, 6:35 PM MDT | Severe Thunderstorm Warning | BOU | Logan | 40 min |
| Jul 21, 6:36 PM MDT | Severe Thunderstorm Warning | BOU | Logan | 39 min |
| Jul 21, 6:58 PM MDT | Severe Thunderstorm Warning | BOU | Washington | 47 min |
| Jul 21, 7:16 PM MDT | Severe Thunderstorm Warning | BOU | Logan | 44 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.