Alert archive / Colorado / Severe Thunderstorm Warnings in 1997
Severe Thunderstorm Warning 133, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this severe thunderstorm warning at Aug 18, 1997, 2:34 PM MDT for Weld County, Colorado. It was in force for 41 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, 2:34 PM MDT (20:34 UTC)
- Expired
- Aug 18, 1997, 3:15 PM MDT
- In force
- 41 min
- Issued by
- NWS Denver/Boulder, CO
- Area
- Whole counties; the outline is the Mesonet’s reconstruction
County Weld County, CO
The radar
The Cheyenne radar (KCYS), 52 km from the middle of the area, began a volume at 20:35 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, 8.6 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 182035 RRA
SVRDEN
COC123-182115-
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DENVER CO
234 PM MDT MON AUG 18 1997
THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A SEVERE
THUNDERSTORM WARNING EFFECTIVE UNTIL 315 PM MDT FOR PEOPLE IN THE
FOLLOWING COUNTY...
IN NORTHEAST COLORADO
CENTRAL WELD
INCLUDING THE FOLLOWING LOCATIONS
AULT...GALETON...GROVER...PIERCE AND PURCELL
AT 231 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
LINE OF SEVERE THUNDERSTORMS MOVING THROUGH NORTH CENTRAL WELD
COUNTY. THE STRONGEST STORM WAS LOCATED OVER PIERCE...OR ABOUT 14
MILES NORTH OF GREELEY.
AT 225 PM MDT THE PUBLIC REPORTED 3/4 INCH DIAMETER HAIL AND A
FUNNEL CLOUD 5 MILES EAST OF ROCKPORT...OR 32 MILES NORTHEAST OF
GREELEY.
THESE STORMS WERE MOVING EAST-SOUTHEAST AT 25 MILES PER HOUR.
HAIL UP TO ONE INCH IN DIAMETER...FUNNEL CLOUDS...WIND GUSTS TO 50
MILES PER HOUR AND DEADLY LIGHTNING ARE LIKELY WITH THESE STORMS.
IF YOU ARE IN THE PATH OF THESE STORMS...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.
BAKER
LAT...LON 4096 10413 4049 10449 4059 10485 4093 10454What 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, 11:18 AM MDT, 3 hours 16 minutes before
COZ030-032>050-190600- SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO NATIONAL WEATHER SERVICE DENVER CO 1115 AM 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: DRYER AIR ALOFT...ASSOCIATED WITH SUBSIDENCE BEHIND AN EXITING DISTURBANCE...WILL CONTINUE TO MOVE INTO THE OUTLOOK AREA TODAY. AT THE SURFACE...A LEE TROUGH HAS DEVELOPED OVER THE EASTERN PLAINS. MOIST SOUTHERLY FLOW WILL CONTINUE OVER THE EXTREME EASTERN PORTION OF THE OUTLOOK AREA WITH DRY WESTERLY DOWNSLOPE FLOW TO THE WEST. THE BEST CHANCES FOR SHOWERS AND THUNDERSTORMS THIS AFTERNOON ARE EAST OF A STERLING TO FORT MORGAN TO BYERS LINE. ANY THUNDERSTORMS THAT DO DEVELOP OVER THE OUTLOOK AREA ARE NOT EXPECTED TO REACH SEVERE LEVELS. SPOTTER ACTIVATION IS NOT ANTICIPATED TODAY. FREDIN
Special weather statement, Aug 18, 1:56 PM MDT, 38 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, 38 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, 37 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, 4 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, 0 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
The office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 18, 3:04 PM MDT | Severe Thunderstorm Warning | BOU | Boulder, Larimer, Weld | 56 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.