Alert archive / Colorado / Severe Thunderstorm Warnings in 1991

Severe Thunderstorm Warning 39, NWS Denver/Boulder, CO

May 29, 1991Weld County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at May 29, 1991, 4:47 PM MDT for Weld County, Colorado. It was in force for 43 min.

The area

The counties it named.

The facts

Issued: May 29, 1991, 4:47 PM MDT (22:47 UTC)
Expired: May 29, 1991, 5:30 PM MDT
In force: 43 min
Issued by: NWS Denver/Boulder, CO
Area: Whole counties

County Weld County, CO

The nearest sounding before it

Denver, CO (KDEN), launched 12:00Z, 10.8 hours before the alert went out and 125 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: 2 J/kg
Mixed-layer CIN: -300 J/kg
Mixed-layer LCL: 1277 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: -24 m²/s²
0-3 km storm-relative helicity: 84 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 29, 2:56 PM MDT, 1 hour 51 minutes before

COZ011-012-292115-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
255 PM MDT WED MAY 29 1991

...STRONG THUNDERSTORMS DEVELOPING ALONG THE FRONT RANGE...

AT 250 PM MDT NATIONAL WEATHER SERVICE RADAR AT LIMON INDICATED
STRONG THUNDERSTORMS DEVELOPING ALONG THE FRONT RANGE.  THE STRONGEST
THUNDERSTORM WAS LOCATED OVER BOULDER...OR 25 MILES NORTHWEST OF
DOWNTOWN DENVER.  THIS THUNDERSTORM WAS MOVING TO THE NORTH-NORTHEAST AT
15 TO 25 MPH AND WILL BE AFFECTING THE TOWNS OF NIWOT...LOUISVILLE AND
OTHER AREAS AROUND BOULDER BY 315 PM MDT.

PERSONS ALONG THE FRONT RANGE...ESPECIALLY IN BOULDER COUNTY...SHOULD
BE ON THE LOOKOUT FOR THESE THUNDERSTORMS AS THEY ARE CAPABLE OF
PRODUCING BRIEF HEAVY RAIN...SMALL HAIL...STRONG WINDS...AND DANGEROUS
LIGHTNING.  IF THREATENING WEATHER APPROACHES...SEEK SHELTER IN A
REINFORCED STRUCTURE AND WAIT FOR THE STORM TO PASS.

PERSONS SHOULD ALSO CONTINUE TO MONITOR NOAA WEATHER RADIO...TELEVISION
OR COMMERCIAL RADIO FOR LATER STATEMENTS AND/OR POSSIBLE WARNINGS.

HEITKAMP

Special weather statement, May 29, 3:52 PM MDT, 55 minutes before

COZ011-012-292230-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
352 PM MDT WED MAY 29 1991

    ...STRONG THUNDERSTORMS CONTINUE TO DEVELOP ALONG FRONT RANGE...

AT 340 PM MDT...NATIONAL WEATHER SERVICE RADAR INDICATED STRONG
THUNDERSTORMS DEVELOPING ALONG THE FRONT RANGE NORTH OF DENVER.  THE
STRONGEST STORM WAS LOCATED IN EASTERN WELD COUNTY 10 WEST OF GOODRICH.
THE STORM WAS MOVING EAST AT 20 TO 25 MILES AN HOUR.  A SECOND STORM WAS
LOCATED IN FAR SOUTHWESTERN WELD COUNTY ABOUT 8 MILES SOUTHWEST OF
PLATTEVILLE.  THIS STORM WAS MOVING NORTHEAST AT ABOUT 20 MILES AN HOUR.

THESE STORMS HAVE THE POTENTIAL TO PRODUCE LARGE HAIL...STRONG WINDS...
HEAVY RAIN AND FREQUENT LIGHTNING.  PERSONS IN GOODRICH...WELDONA...LOG
LANE VILLAGE...FORT MORGAN...PLATTEVILLE...GILCREST...PECKHAM AND LA
SALLE CAN EXPECT THUNDERSTORMS TO APPROACH BY AT LEAST 430 PM MDT.

RESIDENTS OF WELD AND WESTERN MORGAN COUNTIES SHOULD BE ALERT TO RAPIDLY
CHANGING WEATHER CONDITIONS AND BE PREPARED TO MOVE TO SAFETY SHOULD
THREATENING WEATHER APPROACH.

PERSONS SHOULD ALSO CONTINUE TO MONITOR NOAA WEATHER RADIO...TELEVISION
OR LOCAL RADIO FOR LATER STATEMENTS AND POSSIBLE WARNINGS.

DEL3GADO

The office that day

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

Issued	Product	Office	Counties	Lasted
May 28, 9:52 PM MDT	Severe Thunderstorm Warning	BOU	Arapahoe, Denver, Jefferson	53 min
May 29, 4:06 PM MDT	Severe Thunderstorm Warning	BOU	Morgan, Weld	39 min
May 29, 5:20 PM MDT	Severe Thunderstorm Warning	BOU	Morgan, Weld	55 min
May 29, 5:39 PM MDT	Tornado Warning	BOU	Weld	36 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.