Alert archive / Colorado / Severe Thunderstorm Warnings in 1997
Severe Thunderstorm Warning 134, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this severe thunderstorm warning at Aug 18, 1997, 3:04 PM MDT for Boulder County, Larimer County, Weld County, Colorado. It was in force for 56 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, 3:04 PM MDT (21:04 UTC)
- Expired
- Aug 18, 1997, 4:00 PM MDT
- In force
- 56 min
- Issued by
- NWS Denver/Boulder, CO
- Area
- Whole counties; the outline is the Mesonet’s reconstruction
Counties Boulder County, CO, Larimer County, CO, Weld County, CO
The radar
The Denver radar (KFTG), 65 km from the middle of the area, began a volume at 21:05 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, 9.1 hours before the alert went out and 144 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 182104 RRA
SVRDEN
COC013-069-123-182205-
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DENVER CO
304 PM MDT MON AUG 18 1997
THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A SEVERE
THUNDERSTORM WARNING EFFECTIVE UNTIL 400 PM MDT FOR PEOPLE IN THE
FOLLOWING COUNTIES...
IN NORTHEAST COLORADO
NORTHEASTERN BOULDER AND SOUTHWESTERN WELD
IN NORTH CENTRAL COLORADO
SOUTHEASTERN LARIMER
INCLUDING THE FOLLOWING LOCATIONS
GREELEY...BERTHOUD...EVANS...GILCREST...JOHNSTOWN...KERSEY...
LA SALLE...LOVELAND...MEAD...MILLIKEN...MILTON RESERVOIR...
PLATTEVILLE AND WINDSOR
AT 300 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM 4 MILES SOUTH OF LOVELAND...OR ABOUT 15 MILES
SOUTH OF FORT COLLINS.
THIS STORM HAS HAD A RECENT HISTORY OF PRODUCING PEA TO MARBLE SIZE
HAIL AND VERY HEAVY RAIN. A SPOTTER REPORTED SMALL HAIL COVERING
THE GROUND NEAR HORSETOOTH RESERVOIR...OF 3 MILES SOUTHWEST OF FORT
COLLINS.
THIS STORM WAS MOVING EAST-SOUTHEAST AT 15 TO 20 MILES PER HOUR.
HAIL UP TO ONE INCH IN DIAMETER...RAINFALL RATES OF 1 TO 1 1/2
INCHES PER HOUR AND WIND GUSTS TO 50 MILES PER HOUR ARE 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 NATION0AL WEATHER SERVICE FORECAST
OFFICE IN DENVER.
BAKER
LAT...LON 4035 10451 4008 10483 4033 10528 4054 10493What 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, 1:56 PM MDT, 1 hour 8 minutes before
COZ033-035-038-039-042-043-182050- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DENVER CO 156 PM MDT MON AUG 18 1997 ...STRONG THUNDERSTORMS MOVING THROUGH EASTERN LARIMER...NORTHERN BOULDER AND WESTERN WELD COUNTIES IN NORTHEAST COLORADO... AT 150 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A LINE OF THUNDERSTORMS MOVING THROUGH NORTHERN BOULDER...EASTERN LARIMER AND EXTREME NORTHWEST WELD COUNTIES. THE STRONGEST STORMS WERE LOCATED 3 MILES SOUTH OF BELLVUE...OR ABOUT 5 MILES WEST OF FORT COLLINS AND 4 MILES NORTH OF ROCKPORT...OR 35 MILES NORTH OF GREELEY. AT 148 PM MDT THE PUBLIC REPORTED 3/8 INCH DIAMETER HAIL IN FORT COLLINS AND FUNNEL CLOUDS WITH THE THUNDERSTORM CROSSING INTO EXTREME NORTHWEST WELD COUNTY. THESE STORMS WERE MOVING EAST-SOUTHEAST AT 25 MILES PER HOUR. PERSONS IN OR NEAR FORT COLLINS...GREELEY...LONGMONT...AULT...BELLVUE...BERTHOUD...CARR... EATON...EVANS...FIRESTONE...GILCREST...GROVER...HEREFORD...LA SALLE...LOVELAND...LUCERNE...NUNN...PIERCE...ROCKPORT...TIMNATH AND WINDSOR 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 STRONG GUSTY WINDS WILL OCCUR WITH THIS STORM. STORMS MAY ALSO PRODUCE SHORT LIVED FUNNEL CLOUDS. TO REPORT SEVERE WEATHER...RELAY YOUR REPORT TO YOUR LOCAL LAW ENFORCEMENT AGENGY. THEY WILL INTURN RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE IN DENVER. BAKER
Special weather statement, Aug 18, 1:56 PM MDT, 1 hour 8 minutes before
COZ033-035-038-039-042-043-182050- SPECIAL WEATHER STATEMENT ...CORRECTION... NATIONAL WEATHER SERVICE DENVER CO 156 PM MDT MON AUG 18 1997 ...STRONG THUNDERSTORMS MOVING THROUGH EASTERN LARIMER...NORTHERN BOULDER AND WESTERN WELD COUNTIES IN NORTHEAST COLORADO... AT 150 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A LINE OF THUNDERSTORMS MOVING THROUGH NORTHERN BOULDER...EASTERN LARIMER AND EXTREME NORTHWEST WELD COUNTIES. THE STRONGEST STORMS WERE LOCATED 3 MILES SOUTH OF BELLVUE...OR ABOUT 5 MILES WEST OF FORT COLLINS AND 4 MILES NORTH OF ROCKPORT...OR 35 MILES NORTH OF GREELEY. AT 148 PM MDT THE PUBLIC REPORTED 3/8 INCH DIAMETER HAIL IN FORT COLLINS AND FUNNEL CLOUDS WITH THE THUNDERSTORM CROSSING INTO EXTREME NORTHWEST WELD COUNTY. THESE STORMS WERE MOVING EAST-SOUTHEAST AT 25 MILES PER HOUR. PERSONS IN OR NEAR FORT COLLINS...GREELEY...LONGMONT...AULT... BELLVUE...BERTHOUD...CARR...EAT ON...EVANS...FIRESTONE...GILCREST... GROVER...HEREFORD...LA SALLE...LOVELAND...LUCERNE...NUNN... PIERCE...ROCKPORT...TIMNATH AND WINDSOR 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 STRONG GUSTY WINDS WILL OCCUR WITH THIS STORM. STORMS MAY ALSO PRODUCE SHORT LIVED FUNNEL CLOUDS. TO REPORT SEVERE WEATHER...RELAY YOUR REPORT TO YOUR LOCAL LAW ENFORCEMENT AGENGY. THEY WILL INTURN RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE IN DENVER. BAKER
Special weather statement, Aug 18, 1:57 PM MDT, 1 hour 7 minutes before
COZ033-035-038-039-042-043-182050- SPECIAL WEATHER STATEMENT ...CORRECTION... NATIONAL WEATHER SERVICE DENVER CO 156 PM MDT MON AUG 18 1997 ...STRONG THUNDERSTORMS MOVING THROUGH EASTERN LARIMER...NORTHERN BOULDER AND WESTERN WELD COUNTIES IN NORTHEAST COLORADO... AT 150 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A LINE OF THUNDERSTORMS MOVING THROUGH NORTHERN BOULDER...EASTERN LARIMER AND EXTREME NORTHWEST WELD COUNTIES. THE STRONGEST STORMS WERE LOCATED 3 MILES SOUTH OF BELLVUE...OR ABOUT 5 MILES WEST OF FORT COLLINS AND 4 MILES NORTH OF ROCKPORT...OR 35 MILES NORTH OF GREELEY. AT 148 PM MDT THE PUBLIC REPORTED 3/8 INCH DIAMETER HAIL IN FORT COLLINS AND FUNNEL CLOUDS WITH THE THUNDERSTORM CROSSING INTO EXTREME NORTHWEST WELD COUNTY. THESE STORMS WERE MOVING EAST-SOUTHEAST AT 25 MILES PER HOUR. PERSONS IN OR NEAR FORT COLLINS...GREELEY...LONGMONT...AULT... BELLVUE...BERTHOUD...CARR...EAT ON...EVANS...FIRESTONE...GILCREST... GROVER...HEREFORD...LA SALLE...LOVELAND...LUCERNE...NUNN... PIERCE...ROCKPORT...TIMNATH AND WINDSOR 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 STRONG GUSTY WINDS WILL OCCUR WITH THIS STORM. STORMS MAY ALSO PRODUCE SHORT LIVED FUNNEL CLOUDS. TO REPORT SEVERE WEATHER...RELAY YOUR REPORT TO YOUR LOCAL LAW ENFORCEMENT AGENGY. THEY WILL INTURN RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE IN DENVER. BAKER
Special weather statement, Aug 18, 2:30 PM MDT, 34 minutes before
COZ030-032>050-190600- SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO NATIONAL WEATHER SERVICE DENVER CO ...UPDATED... 230 PM MDT MON AUG 18 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: A UPPER LEVEL DISTURBANCE TRACKING OVER NORTHERN COLORADO HAS COMBINED WITH DAYTIME HEATING TO PRODUCE THUNDERSTORMS CONTAINING HEAVY RAIN AND HAIL. AN AMPLE SUPPLY OF SURFACE MOISTURE RESIDES OVER THE EASTERN PLAINS DUE TO CONTINUOUS SOUTHEASTERLY FLOW. THUNDERSTORMS ARE CAPABLE OF BECOMING SEVERE THROUGH THE REST AFTERNOON AS THUNDERSTORMS MAY CONTAIN LARGE HAIL...GUSTY WINDS AND TORRENTIAL RAINFALL. SPOTTER ACTIVATION ALONG WITH RAINFALL REPORTS WILL BE NEEDED THROUGH THE REST OF THE AFTERNOON AND POSSIBLY INTO THE EARLY EVENING. FREDIN
Special weather statement, Aug 18, 2:34 PM MDT, 30 minutes before
COZ030-032>050-190600- SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO NATIONAL WEATHER SERVICE DENVER CO ...UPDATED... 230 PM MDT MON AUG 18 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: A UPPER LEVEL DISTURBANCE TRACKING OVER NORTHERN COLORADO HAS COMBINED WITH DAYTIME HEATING TO PRODUCE THUNDERSTORMS CONTAINING HEAVY RAIN AND HAIL. AN AMPLE SUPPLY OF SURFACE MOISTURE RESIDES OVER THE EASTERN PLAINS DUE TO CONTINUOUS SOUTHEASTERLY FLOW. THUNDERSTORMS ARE CAPABLE OF BECOMING SEVERE THROUGH THE REST AFTERNOON AS THUNDERSTORMS MAY CONTAIN LARGE HAIL...GUSTY WINDS AND TORRENTIAL RAINFALL. SPOTTER ACTIVATION ALONG WITH RAINFALL REPORTS WILL BE NEEDED THROUGH THE REST OF THE AFTERNOON AND POSSIBLY INTO THE EARLY EVENING. FREDIN
Special weather statement, Aug 18, 2:53 PM MDT, 11 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
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, 3:49 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Arapahoe | 26 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.