Alert archive / Colorado / Severe Thunderstorm Warnings in 1991

Severe Thunderstorm Warning 57, NWS Denver/Boulder, CO

May 31, 1991Adams County, Weld County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at May 31, 1991, 9:44 PM MDT for Adams County, Weld County, Colorado. It was in force for 46 min.

The area

The counties it named.

The facts

Issued
May 31, 1991, 9:44 PM MDT (03:44 UTC)
Expired
May 31, 1991, 10:30 PM MDT
In force
46 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties

Counties Adams County, CO, Weld County, CO

The nearest sounding before it

Denver, CO (KDEN), launched 00:00Z, 3.7 hours before the alert went out and 104 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 1991-06-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 169 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 1991-06-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -14 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
169 J/kg
Mixed-layer CIN
-99 J/kg
Mixed-layer LCL
1122 m above ground
0-6 km bulk shear
62 kt
0-1 km storm-relative helicity
-14 m²/s²
0-3 km storm-relative helicity
160 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, May 31, 9:19 PM MDT, 25 minutes before
COZ011-010500-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
920 PM MDT FRI MAY 31 1991

...THUNDERSTORMS IN DOUGLAS COUNTY...

STRONG THUNDERSTORMS ARE DEVELOPING OVER DOUGLAS COUNTY LATE THIS
EVENING.  THE STRONGEST STORM WAS NORTHEAST OF PALMER LAKE OR ABOUT 40
MILES SOUTH OF DENVER AND WAS MOVING TO THE NORTH AT 25 MPH.

A LINE OF THUNDERSTORMS EXTENDED FROM THIS STRONG STORM NORTH TO NEAR
LITTLETON.  THIS LINE TOO WAS MOVING TO THE NORTH AT ABOUT 25 MPH.

HAIL...LIGHTNING...VERY HEAVY RAIN AND GUSTY WINDS ARE TO BE EXPECTED IN
CENTRAL DOUGLAS COUNTY WITHIN THE NEXT 30 TO 60 MINUTES.  THE SOUTHERN
SECTIONS OF THE DENVER METRO AREA WILL ALSO BE AFFECTED BY THIS LINE OF
STORMS BY 945 PM FRIDAY EVENING.

PERSONS IN THE PATH OF THESE STORMS SHOULD BE ON THE LOOKOUT FOR RAPIDLY
CHANGING WEATHER CONDITIONS AND MOVE TO SAFE SHELTER IF THREATENING
WEATHER APPROACHES.

ET

The office that day

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

IssuedProductOfficeCountiesLasted
May 31, 6:09 PM MDTSevere Thunderstorm WarningBOUBoulder, Jefferson51 min
May 31, 6:12 PM MDTSevere Thunderstorm WarningBOUDouglas48 min
May 31, 6:46 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe59 min
May 31, 7:43 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe62 min
May 31, 8:38 PM MDTSevere Thunderstorm WarningBOUMorgan67 min
May 31, 9:06 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe39 min
May 31, 9:37 PM MDTTornado WarningBOUMorgan38 min
May 31, 10:02 PM MDTTornado WarningBOUAdams, Arapahoe, Washington28 min
May 31, 10:25 PM MDTTornado WarningBOULogan, Morgan, Washington35 min
May 31, 10:26 PM MDTTornado WarningBOUAdams, Washington34 min
May 31, 10:38 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe52 min
May 31, 10:48 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe42 min
May 31, 11:00 PM MDTTornado WarningBOUMorgan, Washington45 min
May 31, 11:05 PM MDTTornado WarningBOULogan, Washington40 min
May 31, 11:33 PM MDTSevere Thunderstorm WarningBOUAdams, Weld42 min
May 31, 11:49 PM MDTSevere Thunderstorm WarningBOUWashington26 min
May 31, 11:51 PM MDTTornado WarningBOULogan24 min
Jun 1, 12:15 AM MDTSevere Thunderstorm WarningBOUWashington30 min
Jun 1, 12:15 AM MDTSevere Thunderstorm WarningBOUWeld45 min
Jun 1, 12:26 AM MDTTornado WarningBOUWashington34 min
Jun 1, 1:01 AM MDTTornado WarningBOUWashington29 min
Jun 1, 4:05 PM MDTSevere Thunderstorm WarningBOUDenver, Jefferson40 min
Jun 1, 4:05 PM MDTSevere Thunderstorm WarningBOUDouglas40 min
Jun 1, 4:36 PM MDTTornado WarningBOUJefferson24 min
Jun 1, 4:57 PM MDTSevere Thunderstorm WarningBOUAdams, Boulder, Denver, Jefferson48 min
Jun 1, 5:20 PM MDTFlash Flood WarningBOUAdams, Jefferson115 min
Jun 1, 5:33 PM MDTTornado WarningBOUBoulder, Jefferson27 min
Jun 1, 5:44 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe, Denver, Jefferson46 min
Jun 1, 5:44 PM MDTSevere Thunderstorm WarningBOUBoulder, Weld46 min

Nearby

Severe Thunderstorm Warnings in Colorado, 1991Every severe thunderstorm warning in 1991

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.