Alert archive / Colorado / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 9, NWS Denver/Boulder, CO

May 25, 19975 counties in Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at May 25, 1997, 5:43 PM MDT for 5 counties in Colorado. It was in force for 32 min. 2 reports came from 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, with what was reported inside it.

The facts

Issued
May 25, 1997, 5:43 PM MDT (23:43 UTC)
Expired
May 25, 1997, 6:15 PM MDT
In force
32 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, Morgan County, CO, Weld County, CO

What was reported inside it

TimeReportWhereRemark
May 25, 5:43 PM MDTHail 1.75Watkins, CO
May 25, 6:05 PM MDTHail 0.75Watkins, CO

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 11.7 hours before the alert went out and 95 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.

Skew-T log-pSkew-T log-p diagram, Denver, CO at 12:00Z on 1997-05-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 108 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 12:00Z on 1997-05-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -151 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
108 J/kg
Mixed-layer CIN
-29 J/kg
Mixed-layer LCL
1057 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
-151 m²/s²
0-3 km storm-relative helicity
-69 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-1.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

554 
WUUS1 KDEN 252344 RRA
SVRDEN
COC001-005-031-087-123-260015-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DENVER CO
543 PM MDT SUN MAY 25 1997

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A SEVERE
THUNDERSTORM WARNING EFFECTIVE UNTIL 615 PM MDT FOR PEOPLE IN THE
FOLLOWING COUNTIES...

IN NORTHEAST COLORADO
     WESTERN ARAPAHOE...NORTHEASTERN DENVER...CENTRAL ADAMS...SOUTH
     CENTRAL WELD AND SOUTHWESTERN MORGAN

INCLUDING THE FOLLOWING LOCATIONS
     NORTHEASTERN AURORA...DENVER INTERNATIONAL AIRPORT...ARAPAHOE
     PARK...BENNETT...BYERS...COUNTRY GARDENS...HOYT...LEADER...
     MANILA VILLAGE...PROSPECT VALLEY...STRASBURG AND WATKINS

AT 532PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A 
SEVERE THUNDERSTORM 9 MILES WEST OF HOYT...OR ABOUT 28 MILES 
SOUTHWEST OF FORT MORGAN.

THE STORM WAS MOVING SOUTHEAST AT 20 MILES PER HOUR.
GOLFBALL HAIL WAS REPORTED NEAR WATKINS AND BENNETT AT 545PM.  

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 3994 10390 3964 10431 3957 10465 3973 10475
          3985 10475 4028 10412

RTG

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, May 25, 3:44 PM MDT, 1 hour 59 minutes before
COZ004-033-034-262200-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
350 PM MDT SUN MAY 25 1997

...WINTER STORM WATCH FOR THE COLORADO NORTHERN MOUNTAINS LATE TONIGHT
   AND MONDAY ABOVE 9500 FEET...

A WINTER STORM WATCH CONTINUES FOR LATE TONIGHT AND MONDAY FOR THE
COLORADO NORTHERN MOUNTAINS ABOVE 9000 FEET.

THIS WATCH INCLUDES THE ELKHEAD AND PARK MOUNTAINS...RABBIT EARS AND
MEDICINE BOW RANGES...ROCKY MOUNTAIN NATIONAL PARK...SUMMIT
COUNTY...MOSQUITO RANGE AND INDIAN PEAKS.

AN UNUSALLY STRONG LATE SEASON STORM SYSTEM WILL MOVE INTO WESTERN
COLORADO TONIGHT AND TRACK INTO EASTERN COLORADO ON MONDAY.  THIS
SYSTEM WILL BRING THE THREAT OF HEAVY SNOW INTO THE COLORADO
NORTHERN MOUNTAINS BY LATE TONIGHT INTO MONDAY ESPECIALLY AT
ELEVATIONS ABOVE 9000 FEET NORTH OF INTERSTATE 70.

TOTAL SNOWFALL ACCUMULATIONS BY MONDAY AFTERNOON ABOVE 9500 FEET IN
THE WATCH AREA MAY RANGE FROM 6 TO 12 INCHES WITH LOCALLY HIGHER
AMOUNTS POSSIBLE.  IN ADDITION NORTHWEST WINDS OF 15 TO 30 MPH WILL
PRODUCE AREAS OF BLOWING SNOW AND REDUCED VISIBILITIES OVER THE
HIGHER MOUNTAIN PASSES.

HOLIDAY TRAVELERS SHOULD EXPECT ICY AND SNOWPACKED ROADS ALONG WITH
AREAS OF LOW VISIBILITIES IN THE NORTHERN MOUNTAINS LATER TONIGHT
AND MONDAY AS THE STORM SYSTEM MOVES ACROSS THE AREA.  ALLOW EXTRA
TIME AND CARRY WARM CLOTHING AND FOOD IN CASE YOU HAVE PROBLEMS.
CAMPERS SHOULD ALSO BE PREPARED FOR THE ADVERSE CONDITIONS.

CONTINUE TO MONITOR NOAA WEATHER RADIO OR THE LOCAL NEWS MEDIA FOR
FURTHER UPDATES.

COLORADO ROAD CONDITIONS ARE AVAILABLE FROM THE STATE DEPARTMENT OF
TRANSPORTATION AT 303-639-1111.

LESZCYNSKI
Special weather statement, May 25, 3:50 PM MDT, 1 hour 53 minutes before
COZ004-033-034-262200-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
350 PM MDT SUN MAY 25 1997

...WINTER STORM WATCH FOR THE COLORADO NORTHERN MOUNTAINS LATE TONIGHT
   AND MONDAY ABOVE 9500 FEET...

A WINTER STORM WATCH CONTINUES FOR LATE TONIGHT AND MONDAY FOR THE
COLORADO NORTHERN MOUNTAINS ABOVE 9000 FEET.

THIS WATCH INCLUDES THE ELKHEAD AND PARK MOUNTAINS...RABBIT EARS AND
MEDICINE BOW RANGES...ROCKY MOUNTAIN NATIONAL PARK...SUMMIT
COUNTY...MOSQUITO RANGE AND INDIAN PEAKS.

AN UNUSALLY STRONG LATE SEASON STORM SYSTEM WILL MOVE INTO WESTERN
COLORADO TONIGHT AND TRACK INTO EASTERN COLORADO ON MONDAY.  THIS
SYSTEM WILL BRING THE THREAT OF HEAVY SNOW INTO THE COLORADO
NORTHERN MOUNTAINS BY LATE TONIGHT INTO MONDAY ESPECIALLY AT
ELEVATIONS ABOVE 9000 FEET NORTH OF INTERSTATE 70.

TOTAL SNOWFALL ACCUMULATIONS BY MONDAY AFTERNOON ABOVE 9500 FEET IN
THE WATCH AREA MAY RANGE FROM 6 TO 12 INCHES WITH LOCALLY HIGHER
AMOUNTS POSSIBLE.  IN ADDITION NORTHWEST WINDS OF 15 TO 30 MPH WILL
PRODUCE AREAS OF BLOWING SNOW AND REDUCED VISIBILITIES OVER THE
HIGHER MOUNTAIN PASSES.

HOLIDAY TRAVELERS SHOULD EXPECT ICY AND SNOWPACKED ROADS ALONG WITH
AREAS OF LOW VISIBILITIES IN THE NORTHERN MOUNTAINS LATER TONIGHT
AND MONDAY AS THE STORM SYSTEM MOVES ACROSS THE AREA.  ALLOW EXTRA
TIME AND CARRY WARM CLOTHING AND FOOD IN CASE YOU HAVE PROBLEMS.
CAMPERS SHOULD ALSO BE PREPARED FOR THE ADVERSE CONDITIONS.

CONTINUE TO MONITOR NOAA WEATHER RADIO OR THE LOCAL NEWS MEDIA FOR
FURTHER UPDATES.

COLORADO ROAD CONDITIONS ARE AVAILABLE FROM THE STATE DEPARTMENT OF
TRANSPORTATION AT 303-639-1111.

LESZCYNSKI
Special weather statement, May 25, 4:00 PM MDT, 1 hour 43 minutes before
COZ039-040-043-252230-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
400 PM MDT SUN MAY 25 1997

...THUNDERSTORMS DEVELOPING RAPIDLY BETWEEN DENVER AND GREELEY...
...WEAK SHORT LIVED TORNADOES POSSIBLE...

AT 345 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
THUNDERSTORMS DEVELOPING RAPIDLY OVER DENVER AND NORTH OF DENVER TO
GREELEY.  THESE THUNDERSTORMS HAVE THE CAPABILITY OF PRODUCING WEAK
SHORT LIVED TORNADOES.

THE STORMS HAVE BEEN MOVING EASTSOUTHEAST AT 15 MILES PER HOUR.

PERSONS IN OR NEAR THE DENVER METRO AREA...DIA...GREELEY...
LONGMONT...BARR LAKE...BRIGHTON...DACONO...ELDORADO
SPRINGS...ERIE...EVANS...FEDERAL HEIGHTS...FIRESTONE...FORT
LUPTON...FREDERICK...GILCREST...HUDSON...JOHNSTOWN...KEENESBURG...LA
SALLE...LAFAYETTE...LOCHBUIE...LOUISVILLE...MEAD...MILLIKEN...MILTON
RESERVOIR...NIWOT...PLATTEVILLE...ROCKY FLATS AND SUPERIOR...

SHOULD BECOME WEATHER WATCHERS AND BE PREPARED TO MOVE TO A PLACE OF
SAFETY IF BAD WEATHER APPROACHES.

RTG
Special weather statement, May 25, 4:01 PM MDT, 1 hour 42 minutes before
COZ039-040-043-252230-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
400 PM MDT SUN MAY 25 1997

...THUNDERSTORMS DEVELOPING RAPIDLY BETWEEN DENVER AND GREELEY...
...WEAK SHORT LIVED TORNADOES POSSIBLE...

AT 345 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
THUNDERSTORMS DEVELOPING RAPIDLY OVER DENVER AND NORTH OF DENVER TO
GREELEY.  THESE THUNDERSTORMS HAVE THE CAPABILITY OF PRODUCING WEAK
SHORT LIVED TORNADOES.

THE STORMS HAVE BEEN MOVING EASTSOUTHEAST AT 15 MILES PER HOUR.

PERSONS IN OR NEAR THE DENVER METRO AREA...DIA...GREELEY...
LONGMONT...BARR LAKE...BRIGHTON...DACONO...ELDORADO
SPRINGS...ERIE...EVANS...FEDERAL HEIGHTS...FIRESTONE...FORT
LUPTON...FREDERICK...GILCREST...HUDSON...JOHNSTOWN...KEENESBURG...LA
SALLE...LAFAYETTE...LOCHBUIE...LOUISVILLE...MEAD...MILLIKEN...MILTON
RESERVOIR...NIWOT...PLATTEVILLE...ROCKY FLATS AND SUPERIOR...

SHOULD BECOME WEATHER WATCHERS AND BE PREPARED TO MOVE TO A PLACE OF
SAFETY IF BAD WEATHER APPROACHES.

RTG
Special weather statement, May 25, 4:10 PM MDT, 1 hour 33 minutes before
COZ047-252245-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
410 PM MDT SUN MAY 25 1997

...THUNDERSTORM IN SOUTHEASTERN LINCOLN. COUNTY...

AT 407 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
THUNDERSTORM IN EXTREME SOUTHEAST LINCOLN COUNTY.  PEA TO SMALL
MARBLE SIZED HAIL WAS REPORTED IN BOYERO AT 405PM.

THE STORM WAS MOVING SOUTHEAST AT 25 MILES PER HOUR...AND WILL MOVE
INTO CHEYENNE COUNTY BY 440PM.

PERSONS IN SOUTHEAST LINCOLN COUNTY SHOULD BE PREPARED TO TAKE COVER
UNTIL THIS STORM PASSES.

THE STORM WILL ALSO CONTAIN DANGEROUS LIGHTNING...BRIEF HEAVY
RAIN...AND WIND GUSTS TO 40 MPH.

RTG
Special weather statement, May 25, 4:16 PM MDT, 1 hour 27 minutes before
COZ047-252245-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
410 PM MDT SUN MAY 25 1997

...THUNDERSTORM IN SOUTHEASTERN LINCOLN. COUNTY...

AT 407 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
THUNDERSTORM IN EXTREME SOUTHEAST LINCOLN COUNTY.  PEA TO SMALL
MARBLE SIZED HAIL WAS REPORTED IN BOYERO AT 405PM.

THE STORM WAS MOVING SOUTHEAST AT 25 MILES PER HOUR...AND WILL MOVE
INTO CHEYENNE COUNTY BY 440PM.

PERSONS IN SOUTHEAST LINCOLN COUNTY SHOULD BE PREPARED TO TAKE COVER
UNTIL THIS STORM PASSES.

THE STORM WILL ALSO CONTAIN DANGEROUS LIGHTNING...BRIEF HEAVY
RAIN...AND WIND GUSTS TO 40 MPH.

RTG

The office that day

Everything else NWS Denver/Boulder, CO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 24, 11:00 PM MDTFlash Flood WarningBOUWeld3 hr
May 25, 5:00 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe, Denver, Weld30 min
May 25, 5:11 PM MDTTornado WarningBOUAdams, Arapahoe29 min
May 25, 5:21 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe, Denver, Morgan, Weld24 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.