Alert archive / Colorado / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 41, NWS Denver/Boulder, CO

July 29, 1990Douglas County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Jul 29, 1990, 2:20 PM MDT for Douglas County, Colorado. It was in force for 40 min.

The area

The counties it named.

The facts

Issued
Jul 29, 1990, 2:20 PM MDT (20:20 UTC)
Expired
Jul 29, 1990, 3:00 PM MDT
In force
40 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties

County Douglas County, CO

The radar

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

The nearest sounding before it

Denver, CO (KDEN), launched 12:00Z, 8.3 hours before the alert went out and 158 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 1990-07-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 78 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 1990-07-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 16 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
78 J/kg
Mixed-layer CIN
-243 J/kg
Mixed-layer LCL
1188 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
16 m²/s²
0-3 km storm-relative helicity
67 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 292023
SVRDEN
COC035-292100-

BULLETIN...IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DENVER CO
220 PM MDT SUN JUL 29 1990

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM
WARNING EFFECTIVE UNTIL 300 PM  MDT FOR PEOPLE IN THE
FOLLOWING COUNTY OF EAST CENTRAL COLORADO:

     SOUTHEASTERN DOUGLAS

INCLUDING THE FOLLOWING TOWNS/CITIES:

     CASTLE ROCK..FRANKTOWN..AND LARKSPUR


AT 220 PM MDT RADAR INDICATED A SEVERE THUNDERSTORM 4 MILES SOUTHEAST
OF CASTLE ROCK...OR ABOUT 31 MILES SOUTH OF DENVER.  MARBLE SIZE   
HAIL HAS BEEN REPORTED WITH THIS STORM.  THE STORM WAS MOVING SLOWLY 
TOWARD THE EAST SOUTHEAST.

IF SEVERE WEATHER APPROACHES YOUR AREA...GO TO A STURDY
SHELTER AWAY FROM CREEK BEDS AND OTHER FLOOD PRONE AREAS.
REMEMBER...A SEVERE THUNDERSTORM CAN PRODUCE LARGE DAMAGING
HAIL...DAMAGING WINDS OF OVER 60 MPH...DEADLY LIGHTNING...AND
HEAVY RAINS THAT CAN QUICKLY FLOOD A LOW LYING AREA.

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.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT FOR MOST OF EASTERN
COLORADO UNTIL 8 PM MDT.

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 3913 10465 3913 10507 3943 10487 3942 10465

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, Jul 29, 1:35 PM MDT, 45 minutes before
COZALL-292100-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE  DENVER CO
135 PM MDT SUNDAY JULY 29 1990

...SEVERE THUNDERSTORM WATCH IN EFFECT UNTIL 8 PM FOR MUCH OF
EASTERN COLORADO...

SATELLITE AND LIGHTNING DETECTORS SHOWED THUNDERSTORMS DEVELOPING
AND MOVING ACROSS THE MOUNTAINS OF COLORADO AT 1PM.  LIMON RADAR SHOWED
THE LEADING EDGE OF THE THUNDERSTORMS ALONG THE FRONT RANGE FROM WEST
OF FORT COLLINS TO WEST OF TRINIDAD.

BY MID AFTERNOON THESE THUNDERSTORMS WILL SPREAD TO THE LOWER
ELEVATIONS OF EASTERN COLORADO...WHERE MORE MOISTURE IS AVAILABLE
AND THE AIRMASS IS VERY UNSTABLE.  THUNDERSTORMS HAVE THE POTENTIAL
TO CONTAIN LARGE HAIL...LOCALLY HEAVY RAINS...AND DAMAGING GUSTY
WINDS.  RESIDENTS OF EASTERN COLORADO SHOULD MONITOR THE WEATHER
THROUGH THE AFTERNOON AND BE PREPARED TO TAKE COVER IF THREATENING
WEATHER APPROACHES.

A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR MUCH OF EASTERN
COLORADO UNTIL 8PM...INCLUDING THE CITIES AND TOWNS OF FORT COLLINS...
METRO DENVER...CASTLE ROCK...COLORADO SPRINGS...PUEBLO...TRINIDAD...
WALSENBURG...GREELEY...STERLING...AKRON...LIMON...FORT MORGAN...
BENNETT...DEER TRAIL...KIOWA...LAS ANIMAS...ORDWAY...AND
EADS%.

RTG
Special weather statement, Jul 29, 1:58 PM MDT, 22 minutes before
COZ004-292100-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE  DENVER CO
200 PM MDT SUNDAY JULY 29 1990

...STRONG THUNDERSTORMS IN EASTERN PARK COUNTY...

AT 155 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED THAT
STRONG THUNDERSTORMS HAD DEVELOPED IN EASTERN PARK COUNTY.  THE MOST
INTENSE STORM WAS LOCATED JUST SOUTH OF LAKE GEORGE...ABOUT 30 MILES
WEST OF COLORADO SPRINGS...AND WAS MOVING TOWARD THE SOUTH SOUTHEAST
AT ABOUT 15 MPH.

THIS STORM IS CAPABLE OF PRODUCING INTENSE LIGHTNING...BRIEF HEAVY
RAIN...STRONG GUSTY WINDS...AND HAIL.  PERSONS IN EASTERN PARK COUNTY
AND IN ADJACENT AREAS TO THE EAST IN TELLER COUNTY SHOULD BE PREPARED
TO TAKE COVER IF A THUNDERSTNORM APPROACHES.

A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR MOST OF EASTERN COLORADO
UNTIL 8PM.

MARKKANEN
Special weather statement, Jul 29, 2:05 PM MDT, 15 minutes before
COZ011-014-292100-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE  DENVER CO
210 PM MDT SUNDAY JULY 29 1990

...HAIL PELTING DOWN YET AGAIN IN DOUGLAS COUNTY...

AT 205 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED THAT
A STRONG THUNDERSTORM HAD DEVELOPED RAPIDLY IN CENTRAL DOUGLAS COUNTY.
AT 2 PM A HAM RADIO OPERATOR REPORTED MARBLE SIZE HAIL FALLING ABOUT
5 MILES SOUTH OF CASTLE ROCK COLORADO...OR ABOUT 30 MILES SOUTH OF
DENVER.  THE STORM WAS MOVING SLOWLY TOWARD THE SOUTHEAST.

PERSONS IN DOUGLAS COUNTY SHOULD WATCH FOR HEAVY RAIN...LIGHTNING...
STRONG WINDS...AND HAIL.  MORE THUNDERSTORMS ARE LIKELY TO DEVELOP
IN DOUGLAS COUNTY AND FARTHER NORTH IN THE DENVER MEWTRO AREA DURING THE
AFTERNOON...AND A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR MOST OF
EASTERN COLORADO UNTIL 8 PM.

MARKKANEN

Nearby

Severe Thunderstorm Warnings in Colorado, 1990Every severe thunderstorm warning in 1990

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.