Alert archive / Colorado / Severe Thunderstorm Warnings in 1997
Severe Thunderstorm Warning 150, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this severe thunderstorm warning at Aug 31, 1997, 5:21 PM MDT for Adams County, Arapahoe County, Denver County, Colorado. It was in force for 39 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 31, 1997, 5:21 PM MDT (23:21 UTC)
- Expired
- Aug 31, 1997, 6:00 PM MDT
- In force
- 39 min
- Issued by
- NWS Denver/Boulder, CO
- Area
- Whole counties; the outline is the Mesonet’s reconstruction
Counties Adams County, CO, Arapahoe County, CO, Denver County, CO
The radar
The Denver radar (KFTG), 8 km from the middle of the area, began a volume at 23:23 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, 11.4 hours before the alert went out and 120 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
- 4 J/kg
- Mixed-layer CIN
- -309 J/kg
- Mixed-layer LCL
- 1804 m above ground
- 0-6 km bulk shear
- 11 kt
- 0-1 km storm-relative helicity
- 9 m²/s²
- 0-3 km storm-relative helicity
- -19 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 312323 RRA
SVRDEN
COC001-005-031-010000-
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DENVER CO
521 PM MDT SUN AUG 31 1997
THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A SEVERE
THUNDERSTORM WARNING EFFECTIVE UNTIL 600 PM MDT FOR PEOPLE IN THE
FOLLOWING COUNTIES...
IN NORTHEAST COLORADO
NORTHWESTERN ARAPAHOE...NORTHEASTERN DENVER AND WESTERN ADAMS
INCLUDING THE FOLLOWING LOCATIONS
NORTHEASTERN AURORA AND DENVER INTERNATIONAL AIRPORT
AT 521 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM OVER CENTRAL AURORA...OR ABOUT 10 MILES EAST OF
DENVER.
THE STORM WAS MOVING NORTHEAST AT 25 MILES PER HOUR.
HAIL OVER ONE INCH IN DIAMETER HAS BEEN REPORTED WITH THIS STORM.
IF YOU ARE IN THE PATH OF THE STORM...PUT YOUR CAR IN A GARAGE AND
MOVE TO A SUBSTANTIAL SHELTER.
HEAVY RAINS ARE ALSO OCCURRING WITH THIS STORM. FLOODING OF LOW
LYING AREAS SUCH AS DITCHES AND UNDERPASSES IS LIKELY. AVOID THESE 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.
REPORT SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY. THEY
WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST
OFFICE IN DENVER.
LAT...LON 3986 10449 3969 10477 3973 10481 3995 10460
GIMMESTAD
&What forecasters said that day
The local office's own words before this severe thunderstorm 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 31, 11:22 AM MDT, 5 hours 59 minutes before
COZ030-032>050-010600- SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO NATIONAL WEATHER SERVICE DENVER CO 1120 AM MDT SUN AUG 31 1997 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: SURFACE DEWPOINTS ACROSS NORTHEAST COLORADO INDICATE THAT LOW LEVEL MOISTURE REMAINS IN PLACE THIS MORNING WHILE SATELLITE PICTURES SHOW MONSOONAL MOISTURE CONTINUING TO MOVE OVER THE STATE FROM THE SOUTHWEST. LATE THIS MORNING... CIRRUS CLOUD COVER OVER NORTHEAST COLORADO WAS DECREASING WHICH WILL ALLOW FOR GOOD SOLAR HEATING THROUGH THE EARLY AFTERNOON. WIDELY SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER THE FOOTHILLS DURING THE MID-AFTERNOON AND THEN SLOWLY MOVE OVER THE ADJACENT PLAINS. A WEAK UPPER LEVEL WEATHER DISTURBANCE OVER SOUTHWESTERN COLORADO THIS MORNING WAS CAUSING SCATTERED SHOWERS OVER THE SAN JUAN MOUNTAINS AND FOUR CORNERS AREA. THIS DISTURBANCE MAY REACH NORTHEAST COLORADO THIS EVENING AND HELP MAINTAIN EVENING THUNDERSTORM ACTIVITY. WINDS ALOFT OVER NORTHEAST COLORADO ARE FAIRLY WEAK TODAY WHICH WILL ALLOW ANY THUNDERSTORMS WHICH DEVELOP TO MOVE SLOWLY. THEREFORE THE MAIN THREAT FROM THE STORMS WILL BE PERIODS OF HEAVY RAINFALL. LOCAL FLOODING MAY DEVELOP IF THUNDERSTORMS BEGIN PRODUCING HEAVY RAINS. THE AIRMASS CONTAINS ENOUGH MOISTURE AT MID AND UPPER LEVELS TO LIMIT THE FORMATION OF ANY LARGE HAIL. NO SEVERE WEATHER IS EXPECTED AND SPOTTER ACTIVATION WILL NOT BE NECESSARY. DANKERS
Nearby
Severe Thunderstorm Warnings in Colorado, 1997Every severe thunderstorm warning in 1997
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.