Alert archive / Colorado / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 20, NWS Denver/Boulder, CO

June 9, 1990Weld County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Jun 9, 1990, 5:19 PM MDT for Weld County, Colorado. It was in force for 41 min. 2 reports 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 9, 1990, 5:19 PM MDT (23:19 UTC)
Expired
Jun 9, 1990, 6:00 PM MDT
In force
41 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties

County 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 9, 5:35 PM MDTHail 2Weld, CO
Jun 9, 5:59 PM MDTTornado F0Weld, 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, 11.3 hours before the alert went out and 125 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 1990-06-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 31 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 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 1990-06-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 42 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
31 J/kg
Mixed-layer CIN
-456 J/kg
Mixed-layer LCL
2000 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
42 m²/s²
0-3 km storm-relative helicity
25 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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, Jun 9, 1:06 PM MDT, 4 hours 13 minutes before
COZ013-092100-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
105 PM MDT SAT JUN 9 1990

...STRONG THUNDERSTORMS DEVELOP OVER JEFFERSON COUNTY...POTENTIAL FOR
   STRONGER THUNDERSTORMS OVER THE METROPLEX...

AT 100 PM MDT STRONG THUNDERSTORMS WERE DEVELOPING OVER CENTRAL AND
WESTERN PARTS OF JEFFERSON COUNTY.  A STRONG STORM WAS LOCATED
IN WEST CENTRAL JEFFERSON COUNTY NEAR THE CITIES OF CONIFER...ASPEN
PARK... AND EVERGREEN.  ANOTHER STRONG STORM WAS LOCATED IN THE WESTERN
PART OF THE METROPLEX NEAR WHEATRIDGE AND ARVADA.

STRONG AND GUSTY WINDS AND HAIL ARE POSSIBLE FROM THESE THUNDERSTORMS
AS THEY MOVE TO THE EAST-NORTHEAST AT 20 MPH.

CONDITIONS EARLY THIS AFTERNOON WERE BECOMING MORE FAVORABLE FOR
STRONGER THUNDERSTORMS FROM AROUND BRIGHTON...SOUTHWEST THROUGH
AURORA...AND SOUTHWEST FROM THERE TO AROUND CASTLE ROCK.  IN FACT...
A BRIEF WEAK FUNNEL CLOUD WAS OBSERVED TO THE SOUTHWEST OF CASTLE ROCK
AND TO THE WEST OF I-25 AT 1255 PM MDT BY THE DOUGLAS COUNTY SHERIFFS
OFFICE.

KEEP LISTENING FOR UPDATES ON THIS AFTERNOONS WEATHER.
Special weather statement, Jun 9, 1:09 PM MDT, 4 hours 10 minutes before
COZ013-092100-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
105 PM MDT SAT JUN 9 1990

...STRONG THUNDERSTORMS DEVELOP OVER JEFFERSON COUNTY...POTENTIAL FOR
   STRONGER THUNDERSTORMS OVER THE METROPLEX...

AT 100 PM MDT STRONG THUNDERSTORMS WERE DEVELOPING OVER CENTRAL AND
WESTERN PARTS OF JEFFERSON COUNTY.  A STRONG STORM WAS LOCATED
IN WEST CENTRAL JEFFERSON COUNTY NEAR THE CITIES OF CONIFER...ASPEN
PARK... AND EVERGREEN.  ANOTHER STRONG STORM WAS LOCATED IN THE WESTERN
PART OF THE METROPLEX NEAR WHEATRIDGE AND ARVADA.

STRONG AND GUSTY WINDS AND HAIL ARE POSSIBLE FROM THESE THUNDERSTORMS
AS THEY MOVE TO THE EAST-NORTHEAST AT 20 MPH.

CONDITIONS EARLY THIS AFTERNOON WERE BECOMING MORE FAVORABLE FOR
STRONGER THUNDERSTORMS FROM AROUND BRIGHTON...SOUTHWEST THROUGH
AURORA...AND SOUTHWEST FROM THERE TO AROUND CASTLE ROCK.  IN FACT...
A BRIEF WEAK FUNNEL CLOUD WAS OBSERVED TO THE SOUTHWEST OF CASTLE ROCK
AND TO THE WEST OF I-25 AT 1255 PM MDT BY THE DOUGLAS COUNTY SHERIFFS
OFFICE.

KEEP LISTENING FOR UPDATES ON THIS AFTERNOONS WEATHER.

MCQUEEN
Special weather statement, Jun 9, 2:07 PM MDT, 3 hours 12 minutes before
COZ013-092100-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
205 PM MDT SAT JUN 9 1990

...TORNADO WATCH MOST OF EASTERN COLORADO EFFECTIVE 2PM UNTIL 8
   PM THIS EVENING...

A TORNADO WATCH HAS BEEN ISSUED FOR MOST OF EASTERN COLORADO AND WILL BE
IN EFFECT FROM 2 PM THIS AFTERNOON...UNTIL 8 PM THIS EVENING. TORNADOES
...LARGE HAIL...DANGEROUS LIGHTNING...PERIODS OF HEAVY RAIN...AND
DAMAGING THUNDERSTORM WINDS CAN BE EXPECTED WITH THESE STORMS.

STRONG THUNDERSTORMS CONTINUED TO DEVELOP IN THE MOIST UNSTABLE AIR
OVER COLORADO THIS AFTERNOON. SATELLITE INDICATED THUNDERSTORMS OVER
THE SOUTHERN AND CENTRAL MOUNTAINS AND EASTERN FOOTHILLS. THESE STORMS
WER*E ON THE INCREASE AND WERE SLOWLY MOVING EAST.

SO FAR...NO SEVERE WEATHER HAS BEEN REPORTED BUT ALL CONCERNED PERSONS
SHOULD STAY TUNED TO NOAA WEATHER RADIO AND MEDIA OUTLETS FOR ADDITIONAL
INFORMATION.

JFR
Special weather statement, Jun 9, 2:41 PM MDT, 2 hours 38 minutes before
COZ013-092200-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
240 PM MDT SAT JUN 9 1990

...STRONG THUNDERSTORMS OVER DOUGLAS COUNTY...
...TORNADO WATCH MOST OF EASTERN COLORADO EFFECTIVE 2PM UNTIL 8
   PM THIS EVENING...

AT 240 PM MDT RADAR WAS SHOWING INTENSIFYING THUNDERSTORMS OVER
DOUGLAS COUNTY.  ONE STRONG THUNDERSTORM WAS ABOUT 5 MILES WEST OF
CASTLE ROCK.  ANOTHER STRONG THUNDERSTORMS WAS ABOUT 5 MILES WEST OF
LARKSPUR.  THESE THUNDERSTORMS WERE MOVING TO THE EAST-NORTHEAST AT
15 MPH.

CENTRAL ARAPAHOE COUNTY AND THE SOUTHEAST HALF OF DOUGLAS COUNTY SHOULD
RECEIVE THE STRONGEST THUNDERSTORMS DURING THE NEXT HOUR.  THIS INCLUDES
THE CITIES OF CASTLE ROCK...FRANKTOWN...BYERS...AND PARKER.

THUS FAR THERE HAVE BEEN NO REPORTS OF SEVERE WEATHER RECEIVED BY THE
DENVER OFFICE OF THE NATIONAL WEATHER SERVICE.  HOWEVER...THUNDERSTORMS
ACROSS EASTERN COLORADO THIS AFTERNOON AND EARLY EVENING HAVE POTExNTIAL
TO PRODUCE VERY STRONG WINDS AND POSSIBLY TORNADOES...LARGE HAIL...
FREQUENT LIGHTNING...AND HEAVY RAIN.

KEEP LISTENING FOR LATER STATEMENTS OR POSSIBLE WARNINGS.

MCQUEEN
Special weather statement, Jun 9, 4:43 PM MDT, 36 minutes before
COZ011-012-092345-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
445 PM MDT SAT JUN 9 1990

...STRONG THUNDERSTORMS OVER EASTERN ARAPAHOE COUNTY...AND A NEW
   ONE IN WELD...

AT 440 PM MDT RADAR INDICATED STRONG THUNDERSTORMS IN EASTERN ARAPAHOE
COUNTY.  THE STRONGEST STORM WAS JUST WEST OF DEER TRAIL...OR ABOUT 50
MILES EAST OF DENVER.  THE STORMS WERE MOVING TOWARD THE EAST NORTHEAST
AT ABOUT 15 MPH.

ANOTHER THUNDERSTORM HAD JUST DEVELOPED RAPIDLY IN WELD COUNTY ABOUT
FIVE MILES NORTH OF GREELEY...AND WAS MOVING SLOWLY TOWARD THE NORTH.

THESE THUNDERSTORMS WILL PROBABLY PRODUCE LOCAL HEAVY RAIN...AS WELL AS
HAIL...STRONG WINDS...AND FREQUENT LIGHTNIXNG.

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

MARKKANEN
Special weather statement, Jun 9, 4:45 PM MDT, 34 minutes before
COZ011-012-092345-

SPECIAL WEATHER STATEMENT...CORRECTED FOR TORNADO WATCH
NATIONAL WEATHER SERVICE DENVER CO
445 PM MDT SAT JUN 9 1990

...STRONG THUNDERSTORMS OVER EASTERN ARAPAHOE COUNTY...AND A NEW
   ONE IN WELD...

AT 440 PM MDT RADAR INDICATED STRONG THUNDERSTORMS IN EASTERN ARAPAHOE
COUNTY.  THE STRONGEST STORM WAS JUST WEST OF DEER TRAIL...OR ABOUT 50
MILES EAST OF DENVER.  THE STORMS WERE MOVING TOWARD THE EAST NORTHEAST
AT ABOUT 15 MPH.

ANOTHER THUNDERSTORM HAD JUST DEVELOPED RAPIDLY IN WELD COUNTY ABOUT
FIVE MILES NORTH OF GREELEY...AND WAS MOVING SLOWLY TOWARD THE NORTH.

THESE THUNDERSTORMS WILL PROBABLY PRODUCE LOCAL HEAVY RAIN...AS WELL AS
HAIL..._STRONG WINDS...AND FREQUENT LIGHTNING.

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

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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.