Alert archive / Colorado / Tornado Warnings in 1990

Tornado Warning 11, NWS Denver/Boulder, CO

July 9, 1990Logan County, Morgan County, Washington County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at Jul 9, 1990, 10:00 PM MDT for Logan County, Morgan County, Washington County, Colorado. It was in force for 45 min.

The area

The counties it named.

The facts

Issued
Jul 9, 1990, 10:00 PM MDT (04:00 UTC)
Expired
Jul 9, 1990, 10:45 PM MDT
In force
45 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties

Counties Logan County, CO, Morgan County, CO, Washington 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, 4.0 hours before the alert went out and 51 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°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 100401
TORDEN
COC121-087-075-100445-

BULLETIN...EBS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DENVER CO
1000 PM MDT MON JUL 09 1990

THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING
EFFECTIVE UNTIL 1045 PM MDT FOR PEOPLE IN THE FOLLOWING
COUNTIES OF NORTHEAST COLORADO:

     NORTH CENTRAL WASHINGTON
     MORGAN
     SOUTHWESTERN LOGAN

INCLUDING THE FOLLOWING TOWNS/CITIES:

     AKRON..ATWOOD..BRUSH..FT MORGAN..HILLROSE..MERINO..
     STERLING..AND WILLARD

AT 1000 PM MDT RADAR WAS INDICATING A LARGE SEVERE THUNDERSTORM WITH A
POSSIBLE TORNADO OVER EAST CENTRAL MORGAN COUNTY.  THIS IS ABOUT 5 MILES
EAST OF FT MORGAN OR 35 MILES SOUTHWEST OF STERLING.  

THIS STORM WAS MOVING TO THE EAST AT 45 MPH.

THIS STORM HAS PRODUCED SEVERE WIND GUSTS OF 60 TO 70 MPH OVER WESTERN
MORGAN COUNTY AND HAS CAUSED POWER BLACKOUTS IN THE FT MORGAN AREA.

TOWNS IN THE PATH INCLUDE BRUSH...WILLARD...GARY...AND SNYDER IN EASTERN
MORGAN COUNTY.  IN WASHINGTON COUNTY PINNEO...XENIA...AND AKRON.  AND IN
LOGAN COUNTY ATWOOD AND STERLING.

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.

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.

LAT..LON  4000 10309 4010 10386 4043 10387 4064 10319

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 9, 6:57 PM MDTTornado WarningBOUAdams, Arapahoe, Denver45 min
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, 10:52 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.