Alert archive / Colorado / Tornado Warnings in 1990

Tornado Warning 8, NWS Denver/Boulder, CO

July 9, 1990Adams County, Arapahoe County, Denver County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at Jul 9, 1990, 6:57 PM MDT for Adams County, Arapahoe County, Denver County, Colorado. It was in force for 45 min.

The area

The counties it named.

The facts

Issued
Jul 9, 1990, 6:57 PM MDT (00:57 UTC)
Expired
Jul 9, 1990, 7:42 PM MDT
In force
45 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties

Counties Adams County, CO, Arapahoe County, CO, Denver 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 00:00Z, 1.0 hours before the alert went out and 111 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 1990-07-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2289 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 1990-07-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 29 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
2289 J/kg
Mixed-layer CIN
-19 J/kg
Mixed-layer LCL
1419 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
29 m²/s²
0-3 km storm-relative helicity
54 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.8

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KDEN 100105
TORDEN
COC005-031-001-100142-

BULLETIN...EBS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DENVER CO
657 PM MDT MON JUL 09 1990

THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING
EFFECTIVE UNTIL 742 PM  MDT FOR PEOPLE IN THE FOLLOWING
COUNTIES OF NORTHEAST COLORADO:

     NORTHERN DENVER
     WESTERN ADAMS

INCLUDING THE FOLLOWING TOWNS/CITIES:

     NORTH DENVER...WATKINS...NORTHERN AURORA...NORTHGLENN
     COMMERCE CITY AND THORNTON.

AT 700 PM MDT...A TORNADO WAS SIGHTED ABOUT 10 MILES NORTHEAST OF
DENVERS STAPLETON AIRPORT.  MOVEMENT WAS NOT DETERMINED...BUT IT
SHOULD BE TOWARDS THE EAST ABOUT 10 MPH.  NUMEROUS FUNNEL CLOUDS 
HAVE BEEN REPORTED IN THE NORTHEAST DENVER METRO-AREA...ALONG WITH
LOCALLY HEAVY RAIN...HAIL AND GUSTY WINDS.

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 WEAT"HER SERVICE
AT 361-0663.  DO NOT CALL THIS NUMBER FOR INFORMATION.

DULONG

LAT..LON  3974 10451 3974 10488 3996 10488 3996 10453

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 9, 7:58 PM MDTSevere Thunderstorm WarningBOUDenver, Jefferson32 min
Jul 9, 7:58 PM MDTSevere Thunderstorm WarningBOUAdams, Weld42 min
Jul 9, 9:10 PM MDTTornado WarningBOUWashington43 min
Jul 9, 9:10 PM MDTTornado WarningBOUMorgan, Weld43 min
Jul 9, 10:00 PM MDTTornado WarningBOULogan, Morgan, Washington45 min
Jul 9, 10:52 PM MDTSevere Thunderstorm WarningBOUWashington38 min

Nearby

Tornado Warnings in Colorado, 1990Every tornado warning in 1990Tornadoes 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.