Alert archive / Colorado / Tornado Warnings in 1988

Tornado Warning 15, NWS Denver/Boulder, CO

June 25, 1988Larimer County, Weld County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at Jun 25, 1988, 2:50 PM MDT for Larimer County, Weld County, Colorado. It was in force for 30 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Jun 25, 1988, 2:50 PM MDT (20:50 UTC)
Expired
Jun 25, 1988, 3:20 PM MDT
In force
30 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties

Counties Larimer County, CO, Weld County, CO

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

What was reported inside it

TimeReportWhereRemark
Jun 25, 3:20 PM MDTThunderstorm Wind 0Larimer, 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. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.

The nearest sounding before it

Denver, CO (KDEN), launched 12:00Z, 8.8 hours before the alert went out and 166 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 1988-06-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 157 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 12:00Z on 1988-06-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 61 square meters per square second.1939Sfc1 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
157 J/kg
Mixed-layer CIN
-253 J/kg
Mixed-layer LCL
2039 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
61 m²/s²
0-3 km storm-relative helicity
94 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KDEN 252052
TORDEN
COC123-069-252120-
 
BULLETIN...EBS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DENVER CO
250 PM MDT SAT JUN 25 1988
 
THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING
EFFECTIVE UNTIL 320 PM  MDT FOR PEOPLE IN THE FOLLOWING
COUNTIES OF NORTHEAST COLORADO:
 
     WESTERN WELD
     SOUTHEASTERN LARIMER
 
INCLUDING THE FOLLOWING TOWNS/CITIES:
 
     ERIE AND PLATTEVILLE
 
AT 246 PM A TORNADO WAS SIGHTED 13 MILES WEST OF GREELEY...MOVING 
TOWARD THE NORTHWEST AT ABOUT 15 MPH.
 
IN HOMES GO TO THE BASEMENT OR INTO A CLOSET OR BATHROOM.
IN SCHOOLS..HIGH RISES AND HOSPITALS GO TO AN INTERIOR
HALLWAY ON THE LOWEST FLOOR.  IF IN MOBILE HOMES OR VEHICLES..
EVACUATE THEM AND GO TO A SUBSTANTIAL SHELTER.  IF NO SHELTER
IS AVAILABLE..LIE FLAT IN THE NEAREST DITCH OR OTHER LOW SPOT.
IN ALL CASES..STAY AWAY FROM WINDOWS..DOORS AND OUTSIDE WALLS.
 
INTENSE LIGHTNING IS REPORTED WITH THIS STORM.  IF OUTDOORS..
STAY AWAY FROM HIGH OBJECTS.  MOVE INDOORS IF POSSIBLE.  WHEN
INDOORS..STAY AWAY FROM WINDOWS AND DOORS AND AVOID USING
TELEPHONES AND ELECTRICAL EQUIPMENT.
 
 
TO REPORT SEVERE WEATHER HAVE THE NEAREST LAW ENFORCEMENT
AGENCY RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE OFFICE
IN DENVER..OR CALL YOUR REPORT TO THE NATIONAL WEATHER SERVICE
AT 361-0663.  DO NOT CALL THIS NUMBER FOR INFORMATION.
 
MARKKANEN 
 
LAT..LON  4061 10505 4061 10478 4001 10481 4001 10505

What forecasters said that day

The local office's own words before this tornado 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, Jun 25, 1:03 PM MDT, 1 hour 47 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE  DENVER CO
1240PM MDT   SATURDAY   JUNE 25 1988

...A LINE OF THUNDERSTORMS FORMING IN NORTHEASTERN COLORADO...

A LINE OF STRONG THUNDERSTORMS HAS BEEN DEVELOPING SINCE NOON FROM
NORTH OF COLORADO SPRINGS THROUGH NORTHWESTERN ELBERT COUNTY INTO
EASTERN ADAMS AND ARAPAHOE COUNTIES.  THIS LINE LIES ABOUT 50 TO
70 MILES SOUTH AND EAST OF DENVER.

INTENSE THUNDERSTORMS HAVE FORMED ON THE NORTH END OF THE LINE IN
EASTERN ADAMS AND ARAPAHOE COUNTIES ABOUT 10 MILES WEST OF LAST CHANCE
COLORADO OR 60 MILES EAST OF DENVER.  HEAVY RAIN...HAIL AND LIGHTNING
ARE ACCOMPANYING THESE THUNDERSTORMS AS THEY MOVE TO THE WEST NORTHWEST
ABOUT 15 MPH.  PERSONS TRAVELLING ALONG HIGHWAY 36 OR OTHER ROADS IN
EASTERN ADAMAS AND ARAPAHOE COUNTIES BETWEEN THE TOWNS OF BYERS AND
LAST CHANCE SHOULD USE CAUTION AS LOCAL FLOODING OF LOW LYING AREAS
IS POSSIBLE.

MORE STRONG THUNDERSTORMS ARE EXPECTED DURING THE AFTERNOON AND EVENING
HOURS OVER MUCH OF EASTERN COLORADO.  THE AIRMASS HAS BECOME VERY MOIST
AND UNSTABLE FROM THE PALMER DIVIDE NORTH.  EASTERLY WINDS ALOFT WILL
PUSH ANY SHOWERS AND THUNDERSTORMS TOWARDS THE WEST.  HEAVY RAIN WITH
PERHAPS 1 TO 2 INCHES IN AN HOUR OR SO IS POSSIBLE FROM SOME OF THE
HEAVIER THUNDERSTORMS.  THE AIRMASS IS QUITE WARM ALOFT SO LARGE HAIL
IS NOT EXPECTED BUT SMALL HAIL MAY FALL FROM SOME OF THE THUNDERSTORMS.
SMALL CREEKS AND STREAMS COULD HAVE MINOR RISES IN THETIR WATER LEVELS
AND STREET INTERSECTIONS AND LOW LYING AREAS COULD HAVE LOCAL FLOODING
FROM THE HEAVY RAINFALL BUT NO MAJOR FLOODING IS EXPECTED.

END..GCF...WSFO DENVER
Special weather statement, Jun 25, 1:44 PM MDT, 1 hour 6 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE  DENVER CO
140PM MDT   SATURDAY   JUNE 25 1988

...LINE OF THUNDERSTORMS FROM WELD COUNTY TO DOUGLAS COUNTY...

A LINE OF THUNDERSTORMS EXTENDS FROM SOUTHERN WELD COUNTY EAST OF
KEENESBURG COLORADO THROUGH ADAMS AND ARAPAHOE COUNTIES INTO SOUTHERN
DOUGLAS COUNTY BETWEEN LARKSPUR AND COLORADO SPRINGS.  THIS LINE IS
MOVING EAST ABOUT 15 TO 20 MPH AND CONTAINS SEVERAL HEAVY TO INTENSE
THUNDERSTORMS.  THIS LINE IS ABOUT 20-30 MILES EAST OF DENVER AND WILL
BEGIN TO AFFECT AURORA AND THE EASTERN DENVER METRO AREA BETWEEN 2 AND
3 PM MDT IF IT CONTINUES ITS PRESENT SPEED AND DIRECTION OF MOVEMENT.

ADAMS COUNTY SHERIFF REPORTED A VERY SHORT LIVED TORNADO JUST SOUTH OF
WATKINS AT 135 PM MDT HOWEVER IT DID NO DAMAGE.  HEAVY RAIN AND HAIL
AS WELL AS LIGHTNING ACCOMPANY THESE THUNDERSTORMS.  PERSONS TRAVELLING
ALONG I-70 AND OTHER ROADS FROM THE DENVER METRO AREA EAST TO BEYOND
BYERS AND SOUTH ALONG I-25 TO COLORADO SPRINGS SHOULD USE CAUTION.  THE
HEAVY RAIN MAY CAUSE LOCAL FLOODING OF LOW LYING AREAS AND STREET
INTERSECTIONS.

THE AIRMASS FROM THE PALMER DIVIDE NORTH IS VERY MOIST AND UNSTABLE.
1 TO 2 INCHES OF RAIN IS POSSIBLE IN AN HOUR OR SO FROM SOME OF THE
HEAVIER THUNDERSTORMS.  THE AIRMASS IS QUITE WARM ALOFT SO LARGE HAIL
IS NOT EXPECTED BUT SMALL HAIL MAY FALL FROM SOME OF THE THUNDERSTORMS.
SMALL CREEKS AND STREAMS COULD HAVE MINOR RISES IN THEIR WATER LEVELS
AND STREET INTERSECTIONS AND LOW LYING AREAS COULD HAVE LOCAL FLOODING
FROM THE HEAVY RAINFALL BUT NO MAJOR FLOODING IS EXPECTED.

ADDITIONAL STATEMENTS WILL BE ISSUED AS INFORMATION BECOMES AVAILABLE.

END..GCF...WSFO DENVER
Special weather statement, Jun 25, 2:41 PM MDT, 9 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE  DENVER CO
240PM MDT SATURDAY JUNE 25 1988

...LINE OF THUNDERSTORMS MOVING NORTHWEST ALONG FRONT RANGE...

A LINE OF THUNDERSTORMS EXTENDS FROM CENTRAL JEFFERSON COUNTY NEAR
CHATFIELD RESERVOIR THROUGH THE DENVER METROPOLITAN AREA AND NORTH TO
THE GREELEY AREA.  THE LINE IS MOVING TOWARD THE NORTHWEST AT ABOUT
15 MPH..AND WILL BE PASSING THROUGH THE WESTERN DENVER METRO AREA...
EASTERN BOULDER...SOUTHWESTERN WELD...AND SOUTHEASTERN LARIMER
COUNTIES BETWEEN NOW AND 330 PM.

THIS LINE OF THUNDERSTORMS WILL PRODUCE BRIEF HEAVY RAIN AND STRONG
GUSTY WINDS.  RAINFALL OF UP TO AN INCH...AND WINDS AS STRONG AS 50
MPH ARE POSSIBLE.  A GUST OF 51 MPH WAS RECORDED AT DENVERS STAPLETON
AIRPORT AT 221 PM MDT.

MARKKANEN

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 25, 1:58 PM MDTSevere Thunderstorm WarningBOUAdams, Weld62 min
Jun 25, 3:31 PM MDTSevere Thunderstorm WarningBOULarimer, Weld49 min

Nearby

Tornado Warnings in Colorado, 1988Every tornado warning in 1988Tornadoes in 1988

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.