Alert archive / Colorado / Severe Thunderstorm Warnings in 1991

Severe Thunderstorm Warning 49, NWS Denver/Boulder, CO

May 31, 1991Adams County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at May 31, 1991, 5:14 PM MDT for Adams County, Colorado. It was in force for 46 min.

The area

The counties it named.

The facts

Issued: May 31, 1991, 5:14 PM MDT (23:14 UTC)
Expired: May 31, 1991, 6:00 PM MDT
In force: 46 min
Issued by: NWS Denver/Boulder, CO
Area: Whole counties

County Adams County, CO

The nearest sounding before it

Denver, CO (KDEN), launched 12:00Z, 11.2 hours before the alert went out and 95 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1512 m above ground
0-6 km bulk shear: 51 kt
0-1 km storm-relative helicity: -33 m²/s²
0-3 km storm-relative helicity: 72 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KDEN 312315
SVRDEN
COC001-010000-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DENVER CO
514 PM MDT FRI MAY 31 1991

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A SEVERE
THUNDERSTORM WARNING EFFECTIVE UNTIL 600 PM MDT FOR PEOPLE IN
THE FOLLOWING COUNTIES

IN NORTHEASTERN COLORADO
     CENTRAL ADAMS

INCLUDING THE FOLLOWING TOWNS/CITIES
     BENNETT

AT 514 PM MDT RADAR INDICATED A SEVERE THUNDERSTORM 4 MILES WEST OF
BENNETT ...OR ABOUT 22 MILES EAST OF DENVER. 

THE STORM WAS MOVING NORTHEAST AT ABOUT 10 TO 15 MILES AN HOUR.

IF SEVERE WEATHER APPROACHES YOUR AREA...GO INSIDE A STURDY
SHELTER AWAY FROM CREEK BEDS AND OTHER FLOOD PRONE AREAS.
REMEMBER...A SEVERE THUNDERSTORM CAN PRODUCE LARGE DAMAGING
HAIL...DAMAGING WINDS OF OVER 60 MPH...DEADLY LIGHTNING...AND
HEAVY RAINS THAT CAN QUICKLY FLOOD A LOW LYING AREA.

TO REPORT SEVERE WEATHER HAVE THE NEAREST LAW ENFORCEMENT
AGENCY RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE
FORECAST OFFICE IN DENVER.

DELGADO

LAT...LON 3974 10442 3974 10455 4001 10439 4001 10410

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, 3:06 PM MDT, 2 hours 8 minutes before

COZ011-312200-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
305 PM MDT THU MAY 30 1991

     ...THUNDERSTORMS DEVELOPING IN SOUTHERN METRO DENVER AREA...

THUNDERSTORMS WERE DEVELOPING IN NORTHERN DOUGLASS AND WESTERN ARAPAHOE
COUNTIES THIS AFTERNOON.  AT 300 PM MDT...NATIONAL WEATHER SERVICE
DOPPLER RADAR INDICATED A COUPLE OF THUNDERSTORMS NEAR SOUTHERN AURORA
AND ALSO JUST SOUTH OF LITTLETON.  THE STORMS WERE MOVING NORTH
NORTHEAST AT ABOUT 20 MILES AN HOUR.

THESE STORMS COULD PRODUCE HAIL...GUSTY WIND AND BRIEF HEAVY RAIN.
MINOR STREET FLOODING IS ALSO POSSIBLE.  RESIDENTS OF THE METRO DENVER
AREA SHOULD MONITOR WEATHER CONDITIONS AND BE PREPARED TO TAKE THE
NECESSARY SAFETY PRECAUTIONS SHOULD THREATENING WEATHER APPROACH.

STAY TUNED TO NOAA WEATHER RADIO...COMMERCIAL RADIO OR TELEVISION FOR
LATER STATEMENTS AND POSSIBLE WARNINGS.

DELGADO...WSFO DENVER

The office that day

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

Issued	Product	Office	Counties	Lasted
May 31, 3:29 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe, Denver	31 min
May 31, 3:29 PM MDT	Severe Thunderstorm Warning	BOU	Douglas	31 min
May 31, 3:56 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe, Denver	34 min
May 31, 4:20 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe, Denver	40 min
May 31, 4:20 PM MDT	Severe Thunderstorm Warning	BOU	Douglas	40 min
May 31, 4:30 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe	45 min
May 31, 4:56 PM MDT	Severe Thunderstorm Warning	BOU	Arapahoe, Douglas	49 min
May 31, 5:45 PM MDT	Severe Thunderstorm Warning	BOU	Arapahoe	60 min

Nearby

Severe Thunderstorm Warnings in Colorado, 1991 Every 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.