Alert archive / Colorado / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 23, NWS Denver/Boulder, CO

June 14, 1990Washington County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Jun 14, 1990, 8:15 PM MDT for Washington County, Colorado. It was in force for 40 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 14, 1990, 8:15 PM MDT (02:15 UTC)
Expired
Jun 14, 1990, 8:55 PM MDT
In force
40 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties

County Washington 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 14, 8:15 PM MDTHail 1.75Washington, CO
Jun 14, 8:36 PM MDTHail 2.75Washington, 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 00:00Z, 2.3 hours before the alert went out and 11 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 00:00Z on 1990-06-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 962 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 00:00Z on 1990-06-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 94 square meters per square second.19395878Sfc1 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
962 J/kg
Mixed-layer CIN
-122 J/kg
Mixed-layer LCL
2454 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
94 m²/s²
0-3 km storm-relative helicity
409 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KDEN 150218
SVRDEN
COC121-150255-

BULLETIN...IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DENVER CO
815 PM MDT THU JUN 14 1990

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM
WARNING EFFECTIVE UNTIL 855 PM  MDT FOR PEOPLE IN THE
FOLLOWING COUNTIES OF NORTHEAST COLORADO:

     NORTHERN AND CENTRAL WASHINGTON

INCLUDING THE FOLLOWING TOWNS/CITIES:

     AKRON AND OTIS

THE STORM WAS LOCATED VERY NEAR AKRON..WHICH IS 32 MILES SOUTH
OF STERLING.  RADAR INDICATED THE STORM MOVING EAST AT 20 MPH. 

AT 812 PM A WEATHER SPOTTER IN AKRON REPORTED MARBLE TO GOLF BALL SIZED
HAIL.  

A TORNADO WATCH REMAINS IN EFFECT UNTIL MIDNIGHT TONIGHT.  THIS STORM
HAS A HISTORY OF PRODUCING FUNNEL CLOUDS...AND A TORNADO IS POSSIBLE. 
SO BE ON THE LOOKOUT AND BE PREPARED TO MOVE TO A PLACE
OF SAFETY IF ONE IS SPOTTED.

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.

RTG

LAT..LON  3990 10283 3991 10342 4036 10344 4037 10282

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 14, 3:10 PM MDT, 5 hours 5 minutes before
COZ011-012-013-014-142330-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
300 PM MDT THU JUN 14 1990

...TORNADO WATCH UNTIL 10PM THIS EVENING FOR NORTHEAST COLORADO...

THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WATCH FOR PARTS
OF NORTHEAST COLORADO FROM THE PALMER DIVIDE NORTH TO THE WYOMING
BORDER...INCLUDING MANY OF THE LARGER CITIES ALONG THE FRONT
RANGE EASTWARD...BUT NOT INCLUDING THE NORTHEAST CORNER OF THE STATE.

ALONG THE HEAVILY POPULATED FRONT RANGE...THE GREATEST THREAT OF
SEVERE WEATHER WILL BE ON THE PLAINS...WITH A LESSER THREAT NEAR THE
FOOTHILLS.  EASTERN AND NORTHERN METROPOLITAN DENVER ARE INCLUDED IN
THE WATCH...BUT BOULDER AND GOLDEN WILL BE WEST OF THE WATCH.

STRONG WINDS ALOFT...WITH MOIST EASTERLY WINDS NEAR GROUND LEVEL WILL
CONTINUE THIS AFTERNOON CREATING SOME OF THE CONDITIONS NECESSARY
FOR STRONG THUNDERSTORM DEVELOPMENT.

REMEMBER...A TORNADO WATCH MEANS THAT CONDITIONS ARE FAVORABLE FOR
THE DEVELOPMENT OF SEVERE THUNDERSTORMS INCLUDING TORNADOES.  IF
TORNADOES ARE SIGHTED BY SPOTTERS OR INDICATED BY RADAR...A TORNADO
WARNING WILL BE ISSUED.

RTG
Special weather statement, Jun 14, 5:32 PM MDT, 2 hours 43 minutes before
COZ011-012-013-014-150200-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
530 PM MDT THU JUN 14 1990

...THUNDERSTORMS ARE DEVELOPING RAPIDLY SOUTHEAST OF GREELEY...

AT 525PM NATIONAL WEATHER SERVICE RADAR SHOWED TWO THUNDERSTORMS
DEVELOPING VERY RAPIDLY NEAR ROGGEN...IN SOUTHWEST WELD COUNTY.
THE STORMS APPEARED TO BE MOVING TO THE NORTH.  ANOTHER STORM
WAS DEVELOPING 5 MILES WEST OF GREELEY.

A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR WELD COUNTY...AND
MUCH OF NORTHERN COLORADO UNTIL 10 PM TONIGHT.  HEAVY RAIN...LARGE
HAIL...AND TORNADOES ARE POSSIBLE.  STORMS MAY DEVELOP VERY RAPIDLY.
RESIDENTS OF NORTHEAST COLORADO SHOULD TAKE COVER IF THREATENED BY
SEVERE WEATHER...AND REPORT ANY SEVERE WEATHER TO YOUR NEAREST
LAW ENFORCEMENT AGENCY.

RTG
Special weather statement, Jun 14, 5:35 PM MDT, 2 hours 40 minutes before
COZ011-012-013-014-150200-

SPECIAL WEATHER STATEMENT...CORRECTED FOR TORNADO WATCH
NATIONAL WEATHER SERVICE DENVER CO
530 PM MDT THU JUN 14 1990

...THUNDERSTORMS ARE DEVELOPING RAPIDLY SOUTHEAST OF GREELEY...

AT 525PM NATIONAL WEATHER SERVICE RADAR SHOWED TWO THUNDERSTORMS
DEVELOPING VERY RAPIDLY NEAR ROGGEN...IN SOUTHWEST WELD COUNTY.
THE STORMS APPEARED TO BE MOVING TO THE NORTH.  ANOTHER STORM
WAS DEVELOPING 5 MILES WEST OF GREELEY.

A TORNADO WATCH IS IN EFFECT FOR WELD COUNTY...AND
MUCH OF NORTHERN COLORADO UNTIL 10 PM TONIGHT.  HEAVY RAIN...LARGE
HAIL...AND TORNADOES ARE POSSIBLE.  STORMS MAY DEVELOP VERY RAPIDLY.
RESIDENTS OF NORTHEAST COLORADO SHOULD TAKE COVER IF THREATENED BY
SEVERE WEATHER...AND REPORT ANY SEVERE WEATHER TO YOUR NEAREST
LAW ENFORCEMENT AGENCY.

RTG

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 14, 6:05 PM MDTSevere Thunderstorm WarningBOUMorgan, Weld45 min
Jun 14, 6:50 PM MDTSevere Thunderstorm WarningBOUMorgan, Weld45 min
Jun 14, 8:50 PM MDTSevere Thunderstorm WarningBOUWashington, Yuma40 min
Jun 15, 4:05 PM MDTSevere Thunderstorm WarningBOULogan40 min
Jun 15, 5:10 PM MDTSevere Thunderstorm WarningBOUSedgwick20 min
Jun 15, 5:55 PM MDTSevere Thunderstorm WarningBOUWeld45 min

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.