Alert archive / Colorado / Severe Thunderstorm Warnings in 1997
Severe Thunderstorm Warning 156, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this severe thunderstorm warning at Sep 4, 1997, 6:37 PM MDT for Logan County, Washington County, Colorado. It was in force for 38 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
- Sep 4, 1997, 6:37 PM MDT (00:37 UTC)
- Expired
- Sep 4, 1997, 7:15 PM MDT
- In force
- 38 min
- Issued by
- NWS Denver/Boulder, CO
- Area
- Whole counties; the outline is the Mesonet’s reconstruction
Counties Logan County, CO, Washington County, CO
The radar
The Denver radar (KFTG), 155 km from the middle of the area, began a volume at 00:39 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, 0.6 hours before the alert went out and 72 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
- 246 J/kg
- Mixed-layer CIN
- -78 J/kg
- Mixed-layer LCL
- 1872 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 15 m²/s²
- 0-3 km storm-relative helicity
- 89 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 1.0
The text
As transmitted, in the capitals the NWS used until 2016.
000
TTAA00 KDEN 050040 RRA
SVRDEN
COC075-121-050115-
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DENVER CO
637 PM MDT THU SEP 4 1997
THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A SEVERE
THUNDERSTORM WARNING EFFECTIVE UNTIL 715 PM MDT FOR PEOPLE IN THE
FOLLOWING COUNTIES...
IN NORTHEAST COLORADO
NORTHEASTERN WASHINGTON AND SOUTHEASTERN LOGAN
INCLUDING THE FOLLOWING LOCATIONS
STERLING...ATWOOD...BURDETT...FLEMING...ILIFF...LONE STAR...
PREWITT RESERVOIR...PROCTOR AND ST PETERSBURG
THIS WARNING REPLACES THE FOLLOWING WARNING FOR NORTHEASTERN
WASHINGTON COUNTY...WHERE THE STORM HAS WEAKENED.
AT 637 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM 10 MILES NORTHWEST OF BURDETT...OR ABOUT 15 MILES
SOUTHEAST OF STERLING.
THE STORM WAS MOVING NORTHEAST AT 35 MILES PER HOUR.
IF SEVERE WEATHER APPROACHES YOUR AREA...GO INSIDE A STURDY SHELTER
AWAY FROM CREEK BEDS AND OTHER FLOOD-PRONE AREAS. REMEMBER...A SEVERE
THUNDERSTORM CAN PRODUCE LARGE DAMAGING HAIL...DAMAGING WINDS OVER 60
MPH...DEADLY LIGHTNING...AND VERY HEAVY RAIN.
LARGE HAIL IS POSSIBLE WITH THIS SEVERE THUNDERSTORM. IF YOU ARE IN
THE PATH OF THE STORM...PUT YOUR CAR IN A GARAGE AND MOVE TO A
SUBSTANTIAL SHELTER.
REPORT SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY. THEY
WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST
OFFICE IN DENVER.
ENTREKIN
LAT...LON 4056 10269 4022 10296 4015 10317 4034 10345
4085 10309 4076 10280What 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, Sep 4, 4:03 PM MDT, 2 hours 34 minutes before
COZ041-042300- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DENVER CO 403 PM MDT THU SEP 4 1997 ...STRONG THUNDERSTORM IN SOUTHEASTERN DOUGLAS AND WEST CENTRAL ELBERT COUNTIES OF COLORADO... AT 359 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM OVER LARKSPUR...OR ABOUT 36 MILES SOUTH OF DENVER. THE STORM WAS MOVING EAST AT 15 TO 20 MILES PER HOUR. PERSONS IN OR NEAR ELBERT...ELIZABETH...GREENLAND...KIOWA...LARKSPUR AND PONDEROSA PARK SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER AND MOVE TO A PLACE OF SAFETY IF BAD WEATHER APPROACHES. DANGEROUS LIGHTNING...SMALL HAIL...BRIEF HEAVY RAIN...AND GUSTY WINDS WILL OCCUR WITH THIS STORM. HEAVY RAINS MAY FLOOD LOW LYING AREAS SUCH AS DITCHES AND UNDERPASSES. 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. INTENSE LIGHTNING IS REPORTED WITH THIS STORM. IF OUTDOORS...STAY AWAY FROM ISOLATED HIGH OBJECTS SUCH AS TREES. MOVE INDOORS IF POSSIBLE. WHEN INDOORS...STAY AWAY FROM WINDOWS AND DOORS AND AVOID USING TELEPHONES UNLESS IT IS AN EMERGENCY. TRY TO UNPLUG UNNECESSARY ELECTRICAL APPLIANCES BEFORE THE THUNDERSTORM APPROACHES. GARD...WSFO DENVER
Special weather statement, Sep 4, 4:04 PM MDT, 2 hours 33 minutes before
COZ041-042300- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DENVER CO 403 PM MDT THU SEP 4 1997 ...STRONG THUNDERSTORM IN SOUTHEASTERN DOUGLAS AND WEST CENTRAL ELBERT COUNTIES OF COLORADO... AT 359 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM OVER LARKSPUR...OR ABOUT 36 MILES SOUTH OF DENVER. THE STORM WAS MOVING EAST AT 15 TO 20 MILES PER HOUR. PERSONS IN OR NEAR ELBERT...ELIZABETH...GREENLAND...KIOWA...LARKSPUR AND PONDEROSA PARK SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER AND MOVE TO A PLACE OF SAFETY IF BAD WEATHER APPROACHES. DANGEROUS LIGHTNING...SMALL HAIL...BRIEF HEAVY RAIN...AND GUSTY WINDS WILL OCCUR WITH THIS STORM. HEAVY RAINS MAY FLOOD LOW LYING AREAS SUCH AS DITCHES AND UNDERPASSES. 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. INTENSE LIGHTNING IS REPORTED WITH THIS STORM. IF OUTDOORS...STAY AWAY FROM ISOLATED HIGH OBJECTS SUCH AS TREES. MOVE INDOORS IF POSSIBLE. WHEN INDOORS...STAY AWAY FROM WINDOWS AND DOORS AND AVOID USING TELEPHONES UNLESS IT IS AN LEMERGENCY. TRY TO UNPLUG UNNECESSARY ELECTRICAL APPLIANCES BEFORE THE THUNDERSTORM APPROACHES. GARD...WSFO DENVER
The office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 4, 6:12 PM MDT | Severe Thunderstorm Warning | BOU | Washington | 33 min |
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.