Alert archive / Colorado / Severe Thunderstorm Warnings in 1997
Severe Thunderstorm Warning 135, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this severe thunderstorm warning at Aug 18, 1997, 3:49 PM MDT for Adams County, Arapahoe County, Colorado. It was in force for 26 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 18, 1997, 3:49 PM MDT (21:49 UTC)
- Expired
- Aug 18, 1997, 4:15 PM MDT
- In force
- 26 min
- 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), 21 km from the middle of the area, began a volume at 21:52 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, 9.8 hours before the alert went out and 92 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
- 38 J/kg
- Mixed-layer CIN
- -318 J/kg
- Mixed-layer LCL
- 1472 m above ground
- 0-6 km bulk shear
- 12 kt
- 0-1 km storm-relative helicity
- 13 m²/s²
- 0-3 km storm-relative helicity
- 11 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 182151 RRA
SVRDEN
COC001-005-182215-
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DENVER CO
349 PM MDT MON AUG 18 1997
THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A SEVERE
THUNDERSTORM WARNING EFFECTIVE UNTIL 415 PM MDT FOR PEOPLE IN THE
FOLLOWING COUNTIES...
IN NORTHEAST COLORADO
CENTRAL ARAPAHOE AND CENTRAL ADAMS
INCLUDING THE FOLLOWING LOCATIONS
BENNETT...BYERS...COUNTRY GARDENS...MANILA VILLAGE...STRASBURG
AND WATKINS
AT 349 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM 6 MILES NORTH OF WATKINS...OR ABOUT 20 MILES EAST
OF DENVER.
THE STORM WAS MOVING EAST SOUTHEAST AT 20 TO 25 MILES PER HOUR.
AT 345 PM MDT A SPOTTER ESTIMATED WINDS TO 60 MPH JUST WEST OF THE
WATKINS EXIT ALONG I-70.
HAIL...INTENSE RAIN AND STRONG DAMAGING WINDS ARE LIKELY WITH THIS
STORM. TAKE COVER IN A SUBSTANTIAL SHELTER UNTIL THE STORM PASSES.
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 3999 10408 3959 10413 3959 10462 3999 10460
FMC
&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 18, 2:53 PM MDT, 56 minutes before
COZ030-032>050-190600- SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO NATIONAL WEATHER SERVICE DENVER CO 253 PM MDT MON AUG 18 1997 ...UPDATE... 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: THUNDERSTORMS WERE ERUPTING OVER THE NORTHERN MOUNTAINS AND ALONG THE FRONT RANGE FOOTHILLS OF NORTHEAST COLORADO THIS AFTERNOON. STORMS WILL TRACK EAST ACROSS THE NORTHEASTERN PLAINS OF COLORADO THIS AFTERNOON...REACHING THE EASTERN BORDER BY THIS EVENING. THE ATMOSPHERE WAS ESPECIALLY PRIMED FOR THUNDERSTORMS ACROSS BOULDER...LARIMER...EASTERN JEFFERSON...ADAMS...ARAPAHOE...ELBERT... WELD...MORGAN...LOGAN AND WASHINGTON COUNTIES. THUNDERSTORMS WILL BE CAPABLE OF LARGE HAIL...VERY HEAVY RAIN...WIND GUSTS TO 50 MILES PER HOUR AND FUNNEL CLOUDS. THE SKYWARN STORM SPOTTER NETWORK IN THE DENVER METRO AREA WILL BE ACTIVATED AS OF 300 PM MDT. BAKER
Special weather statement, Aug 18, 3:05 PM MDT, 44 minutes before
COZ036-039-040-182145- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DENVER CO 305 PM MDT MON AUG 18 1997 ...THUNDERSTORMS SOUTHEASTERN BOULDER AND EASTERN JEFFERSON COUNTIES. AT 305 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A LINE OF STORMS EXTENDING FROM 2 MILES SOUTH OF LOUISVILLE...OR ABOUT 16 MILES NORTHWEST OF DENVER TO NEAR BUFFALO CREEK OR 32 MILES SOUTHWEST OF DENVER. THE STORMS WERE MOVING EAST AT 20 MILES PER HOUR. THE STORMS WILL BE MOVING INTO WESTERN ARAPAHOE...DENVER AND WESTERN ADAMS COUNTIES BY 345 PM PERSONS IN OR NEAR BUFFALO CREEK...CHATFIELD RESERVOIR... ARVADA... NORTHWESTERN AURORA...BROOMFIELD...COMMERCE CITY...DENVER... ENGLEWOOD...NORTHEASTERN GOLDEN...LAKEWOOD...LITTLETON... NORTHGLENN...THORNTON...WESTMINSTER.. .WHEAT RIDGE...BARR LAKE... BRIGHTON...FEDERAL HEIGHTS...GREENWOOD VILLAGE...IDLEDALE...INDIAN HILLS...LAFAYETTE...LOUISVILLE...MORRISON...RED ROCKS PARK... SHERIDAN...SUPERIOR AND TINY TOWN SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER AND MOVE TO A PLACE OF SAFETY IF BAD WEATHER APPROACHES. DANGEROUS LIGHTNING...1/2 INCH DIAMTER HAIL...VERY HEAVY RAIN...AND GUSTY WINDS TO 40 MPH ARE POSSINLE WITH THESE STORMS. 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. FMC
Special weather statement, Aug 18, 3:11 PM MDT, 38 minutes before
COZ036-039-040-182145- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DENVER CO 305 PM MDT MON AUG 18 1997 ...THUNDERSTORMS SOUTHEASTERN BOULDER AND EASTERN JEFFERSON COUNTIES. AT 305 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A LINE OF STORMS EXTENDING FROM 2 MILES SOUTH OF LOUISVILLE...OR ABOUT 16 MILES NORTHWEST OF DENVER TO NEAR BUFFALO CREEK OR 32 MILES SOUTHWEST OF DENVER. THE STORMS WERE MOVING EAST AT 20 MILES PER HOUR. THE STORMS WILL BE MOVING INTO WESTERN ARAPAHOE...DENVER AND WESTERN ADAMS COUNTIES BY 345 PM PERSONS IN OR NEAR BUFFALO CREEK...CHATFIELD RESERVOIR... ARVADA... NORTHWESTERN AURORA...BROOMFIELD...COMMERCE CITY...DENVER... ENGLEWOOD...NORTHEASTERN GOLDEN...LAKEWOOD...LITTLETON... NORTHGLENN...THORNTON...WESTMINSTER.. .WHEAT RIDGE...BARR LAKE... BRIGHTON...FEDERAL HEIGHTS...GREENWOOD VILLAGE...IDLEDALE...INDIAN HILLS...LAFAYETTE...LOUISVILLE...MORRISON...RED ROCKS PARK... SHERIDAN...SUPERIOR AND TINY TOWN SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER AND MOVE TO A PLACE OF SAFETY IF BAD WEATHER APPROACHES. DANGEROUS LIGHTNING...1/2 INCH DIAMTER HAIL...VERY HEAVY RAIN...AND GUSTY WINDS TO 40 MPH ARE POSSINLE WITH THESE STORMS. 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 HIGPHER GROUND IF THREATENED BY FLOOD WATERS. FMC
Special weather statement, Aug 18, 3:12 PM MDT, 37 minutes before
COZ036-039-040-182145- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DENVER CO 305 PM MDT MON AUG 18 1997 ...THUNDERSTORMS SOUTHEASTERN BOULDER AND EASTERN JEFFERSON COUNTIES. AT 305 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A LINE OF STORMS EXTENDING FROM 2 MILES SOUTH OF LOUISVILLE...OR ABOUT 16 MILES NORTHWEST OF DENVER TO NEAR BUFFALO CREEK OR 32 MILES SOUTHWEST OF DENVER. THE STORMS WERE MOVING EAST AT 20 MILES PER HOUR. THE STORMS WILL BE MOVING INTO WESTERN ARAPAHOE...DENVER AND WESTERN ADAMS COUNTIES BY 345 PM PERSONS IN OR NEAR BUFFALO CREEK...CHATFIELD RESERVOIR... ARVADA... NORTHWESTERN AURORA...BROOMFIELD...COMMERCE CITY...DENVER... ENGLEWOOD...GOLDEN...LAKEWOOD...LITTLETON... NORTHGLENN...THORNTON ... WESTMINSTER.. .WHEAT RIDGE...BARR LAKE... BRIGHTON...FEDERAL HEIGHTS...GREENWOOD VILLAGE...IDLEDALE...INDIAN HILLS...LAFAYETTE ...LOUISVILLE...MORRISON...RED ROCKS PARK... SHERIDAN...SUPERIOR AND TINY TOWN SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER AND MOVE TO A PLACE OF SAFETY IF BAD WEATHER APPROACHES. DANGEROUS LIGHTNING...1/2 INCH DIAMTER HAIL...VERY HEAVY RAIN...AND GUSTY WINDS TO 40 MPH ARE POSSINLE WITH THESE STORMS. 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 GROUNDT IF THREATENED BY FLOOD WATERS. FMC
Special weather statement, Aug 18, 3:40 PM MDT, 9 minutes before
COZ036-040-041-045-182215- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DENVER CO 340 PM MDT MON AUG 18 1997 ...THUNDERSTORM IN EASTERN JEFFERSON...NORTHERN DOUGLAS...WESTERN ARAPAHOE...DENVER AND WESTERN ADAMS COUNTIES... AT 335 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A LINE OF STORMS EXTENDING FROM 18 MILES NORTH OF DENVER TO 10 MILES NORTHEAST OF DECKERS OR 27 MILES SOUTHWEST OF DENVER. AT 335 PM MDT A SPOTTER REPORTED A BRIEF FUNNEL CLOUD AND GUN CLUB ROAD AND I-70. THESE STORMS HAVE HAD A HISTORY OF PRODUCING UP TO 1 INCH OF RAIN IN LESS THAN 30 MINUTES AND 1/2 INCH DIAMETER HAIL. THE STORMS WERE MOVING EAST AT 20 MILES PER HOUR. PERSONS IN OR NEAR SOUTHEASTERN ARVADA...AURORA...EASTERN BROOMFIELD...COMMERCE CITY...DENVER INTERNATIONAL AIRPORT...DENVER... ENGLEWOOD...EASTERN LAKEWOOD...LITTLETON...NORTHGLENN...THORNTON... EASTERN WESTMINSTER...EASTERN WHEAT RIDGE...ARAPAHOE PARK...BARR LAKE...BEVERLY HILLS...BRIGHTON...CASTLE ROCK...CHATFIELD RESERVOIR...FEDERAL HEIGHTS...FRANKTOWN...GREENWOOD VILLAGE... HIGHLANDS RANCH...LOUVIERS...PARKER...ROXBOROUGH PARK...SEDALIA... SHERIDAN...SOUTH PLATTE...SPRUCEWOOD...SURREY RIDGE...THE PINERY AND WATKINS SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER AND MOVE TO A PLACE OF SAFETY IF BAD WEATHER APPROACHES. DANGEROUS LIGHTNING...SMALL HAIL...VERY HEAVY RAIN...AND GUSTY WINDS TO 40 MPH ARE POSSIBLE WITH THESE STORMS. THESE STORMS MAY ALSO PRODUCE MORE SHORT LIVED FUNNEL CLOUDS. 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. FMC
Special weather statement, Aug 18, 3:41 PM MDT, 8 minutes before
COZ036-040-041-045-182215- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DENVER CO 340 PM MDT MON AUG 18 1997 ...THUNDERSTORM IN EASTERN JEFFERSON...NORTHERN DOUGLAS...WESTERN ARAPAHOE...DENVER AND WESTERN ADAMS COUNTIES... AT 335 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A LINE OF STORMS EXTENDING FROM 18 MILES NORTH OF DENVER TO 10 MILES NORTHEAST OF DECKERS OR 27 MILES SOUTHWEST OF DENVER. AT 335 PM MDT A SPOTTER REPORTED A BRIEF FUNNEL CLOUD AND GUN CLUB ROAD AND I-70. THESE STORMS HAVE HAD A HISTORY OF PRODUCING UP TO 1 INCH OF RAIN IN LESS THAN 30 MINUTES AND 1/2 INCH DIAMETER HAIL. THE STORMS WERE MOVING EAST AT 20 MILES PER HOUR. PERSONS IN OR NEAR SOUTHEASTERN ARVADA...AURORA...EASTERN BROOMFIELD...COMMERCE CITY...DENVER INTERNATIONAL AIRPORT...DENVER... ENGLEWOOD...EASTERN LAKEWOOD...LITTLETON...NORTHGLENN...THORNTON... EASTERN WESTMINSTER...EASTERN WHEAT RIDGE...ARAPAHOE PARK...BARR LAKE...BEVERLY HILLS...BRIGHTON...CASTLE ROCK...CHATFIELD RESERVOIR...FEDERAL HEIGHTS...FRANKTOWN...GREENWOOD VILLAGE... HIGHLANDS RANCH...LOUVIERS...PARKER...ROXBOROUGH PARK...SEDALIA... SHERIDAN...SOUTH PLATTE...SPRUCEWOOD...SURREY RIDGE...THE PINERY AND WATKINS SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER AND MOVE TO A PLACE OF SAFETY IF BAD WEATHER APPROACHES. DANGEROUS LIGHTNING...SMALL HAIL...VERY HEAVY RAIN...AND GUSTY WINDS TO 40 MPH ARE POSSIBLE WITH THESE STORMS. THESE STORMS MAY ALSO PRODUCE MORE SHORT LIVED FUNNEL CLOUDS. 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. FMC
The office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 18, 2:34 PM MDT | Severe Thunderstorm Warning | BOU | Weld | 41 min |
| Aug 18, 3:04 PM MDT | Severe Thunderstorm Warning | BOU | Boulder, Larimer, Weld | 56 min |
| Aug 18, 4:15 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Arapahoe | 30 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.