Alert archive / Colorado / Severe Thunderstorm Warnings in 1994

Severe Thunderstorm Warning 4, NWS Denver/Boulder, CO

April 25, 1994Adams County, Denver County, Jefferson County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Apr 25, 1994, 8:49 AM MDT for Adams County, Denver County, Jefferson County, Colorado. It was in force for 41 min.

The area

The counties it named.

The facts

Issued
Apr 25, 1994, 8:49 AM MDT (14:49 UTC)
Expired
Apr 25, 1994, 9:30 AM MDT
In force
41 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties

Counties Adams County, CO, Denver County, CO, Jefferson County, CO

The radar

The Denver radar (KFTG), 24 km from the middle of the area, began a volume at 14:52 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Fort Carson/Butt, CO (KFCS), launched 12:00Z, 2.8 hours before the alert went out and 118 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, Fort Carson/Butt, CO at 12:00Z on 1994-04-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Fort Carson/Butt, CO at 12:00Z on 1994-04-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -3 square meters per square second.19395878Sfc1 km3 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2327 m above ground
0-6 km bulk shear
56 kt
0-1 km storm-relative helicity
-3 m²/s²
0-3 km storm-relative helicity
68 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 251450
SVRDEN
COC001-013-031-059-123-251530-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DENVER CO
849 AM MDT MON APR 25 1994

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A SEVERE
THUNDERSTORM WARNING EFFECTIVE UNTIL 930 AM MDT FOR PEOPLE IN
THE FOLLOWING COUNTIES

IN NORTHEASTERN COLORADO
     EXTREME WESTERN ADAMS...EASTERN BOULDER...WEST CENTRAL
     DENVER...NORTHEASTERN JEFFERSON AND EXTREME SOUTHWESTERN
     WELD

INCLUDING THE FOLLOWING LOCATIONS
     ARVADA...BOULDER...BROOMFIELD...DENVER...EDGEWATER...
     ELDORADO SPRINGS...ERIE...GOLDEN...LAFAYETTE...LAKEWOOD...
     LEYDEN...LONGMONT...LOUISVILLE...MARSHALL...MOUNTAIN VIEW
     ...NIWOT...NORTHGLENN...ROCKY FLATS...SUPERIOR...
     WESTMINSTER AND WHEAT RIDGE

AT 849 AM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
A SEVERE THUNDERSTORM OVER LEYDEN ...OR ABOUT 12 MILES
NORTHWEST OF DENVER.

THE PUBLIC REPORTED MARBLE SIZE HAIL IN ARVADA NEAR THE INTERSECTIONS
OF 68TH AVE AND OWEN STREET.

THE STORM WAS MOVING TO THE NORTH ABOUT 20 MPH.

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 OVER 60 MPH...DEADLY LIGHTNING...AND VERY
HEAVY RAIN.

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


LAT...LON 3973 10504 3973 10519 4018 10535 4020 10491

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, Apr 25, 8:05 AM MDT, 44 minutes before
COZ038-042>043-251500-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
805 AM MDT MON APR 25 1994

...THUNDERSTORMS ALONG THE FRONT RANGE...

AT 750 AM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
THUNDERSTORMS ALONG THE FRONT RANGE.  THE STRONGEST THUNDERSTORM WAS
NEAR BERTHOUD IN LARIMER COUNTY...OR 19 MILES SOUTH OF FORT COLLINS.
OTHER STORMS WERE IN DOUGLAS COUNTY NEAR SEDALIA...OR 20 MILES SOUTH OF
DENVER AND JUST WEST OF GOLDEN IN JEFFERSON COUNTY.  THE STORMS WERE
MOVING NORTH NORTHWEST AT 20 MPH.

WEATHER SPOTTERS AT 745 AM REPORTED PEA SIZE HAIL PARTIALLY COVERING THE
GROUND IN BERTHOUD.  PEA SIZE HAIL WAS ALSO REPORTED IN GOLDEN.

PEOPLE ALONG THE FRONT RANGE...INCLUDING FORT COLLINS...LOVELAND...
DENVER AND BOULDER SHOULD BE ALERT FOR GUSTY WINDS...SMALL HAIL AND
FREQUENT LIGHTNING.

LESZCYNSKI

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 25, 8:18 AM MDTSevere Thunderstorm WarningBOUBoulder, Jefferson27 min
Apr 25, 8:18 AM MDTSevere Thunderstorm WarningBOUAdams, Denver27 min
Apr 25, 8:32 AM MDTSevere Thunderstorm WarningBOULarimer, Weld28 min
Apr 25, 8:49 AM MDTSevere Thunderstorm WarningBOUBoulder, Weld41 min
Apr 25, 9:03 AM MDTSevere Thunderstorm WarningBOULarimer, Weld42 min
Apr 25, 9:45 AM MDTSevere Thunderstorm WarningBOUWeld30 min
Apr 25, 1:47 PM MDTSevere Thunderstorm WarningBOUArapahoe, Washington43 min
Apr 25, 2:20 PM MDTTornado WarningBOUWashington25 min
Apr 25, 2:45 PM MDTSevere Thunderstorm WarningBOUWashington25 min

Nearby

Severe Thunderstorm Warnings in Colorado, 1994Every severe thunderstorm warning in 1994

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; radar from the NEXRAD Level II archive.