Alert archive / Colorado / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 166, NWS Denver/Boulder, CO

October 16, 1998Denver County, Jefferson County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Oct 16, 1998, 1:15 PM MDT for Denver County, Jefferson County, Colorado. It was in force for 45 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties.

The facts

Issued
Oct 16, 1998, 1:15 PM MDT (19:15 UTC)
Expired
Oct 16, 1998, 2:00 PM MDT
In force
45 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties; the outline is the Mesonet’s reconstruction

Counties Denver County, CO, Jefferson County, CO

The radar

The Denver radar (KFTG), 45 km from the middle of the area, began a volume at 19:14 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

Denver, CO (KDNR), launched 12:00Z, 7.3 hours before the alert went out and 158 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 12:00Z on 1998-10-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 222 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 12:00Z on 1998-10-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 48 square meters per square second.1939587897Sfc1 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
222 J/kg
Mixed-layer CIN
-118 J/kg
Mixed-layer LCL
629 m above ground
0-6 km bulk shear
60 kt
0-1 km storm-relative helicity
48 m²/s²
0-3 km storm-relative helicity
134 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.

213 
WUUS1 KDEN 161918 RRA
SVRDEN
COC031-059-162000-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DENVER CO
115 PM MDT FRI OCT 16 1998

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WESTERN DENVER COUNTY IN NORTHEAST COLORADO
  EXTREME NORTHEASTERN JEFFERSON COUNTY IN NORTHEAST COLORADO

* UNTIL 200 PM MDT

* AT 114 PM MDT A SEVERE THUNDERSTORM WAS OVER LAKEWOOD...OR ABOUT 7 
MILES WEST OF DENVER...MOVING SOUTHEAST AT 5 MPH.  HAIL UP TO 6 
INCHES DEEP WAS REPORTED IN SOUTHWEST ARVADA WITH THIS STORM.

LOCATIONS IN THE WARNING INCLUDE WESTERN DENVER...WHEAT RIDGE AND 
EASTERN LAKEWOOD.

WHILE THE HAIL WILL NOT BE EXTREMELY LARGE...THE QUANTITY OF HAIL 
WILL CAUSE DAMAGE TO VEGETATION...SLIPPERY STREETS AND LOCALIZED 
FLOODING.

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

LAT...LON 3970 10511 3966 10500 3977 10500 3977 10511

GIMMESTAD

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, Oct 16, 11:00 AM MDT, 2 hours 15 minutes before
COZ038-039-161745-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER COLORADO
1100 AM MDT FRI OCT 16 1998

...PERSISTENT RAIN SHOWERS FALLING OVER EASTERN LARIMER AND
NORTHEASTERN BOULDER COUNTIES THIS MORNING...

AT 11 AM MDT THIS MORNING...WEATHER SERVICE RADAR CONTINUED TO
INDICATE AN AREA OF MODERATE RAIN SHOWERS FALLING ACROSS THE
NORTHERN URBAN CORRIDOR FROM AROUND LONGMONT NORTHWARD THROUGH THE
FORT COLLINS AREA.  RAINFALL ESTIMATES AND REPORTS INDICATE AMOUNTS
FROM THREE TENTHS OF AN INCH TO ONE INCH HAVE FALLEN OVER THE
AREA...WITH JUST OVER ONE INCH AROUND LOVELAND.  MINOR STREET
FLOODING HAS BEEN REPORTED IN LOVELAND AND WESTERN FORT COLLINS.

SMALL HAIL...ICE PELLETS...AND SCATTERED LIGHTNING HAS ALSO BEEN
REPORTED WITH THESE SHOWERS.

EXCESSIVE RUNOFF FROM HEAVY RAIN SHOWERS CAN CAUSE FLOODING OF
SMALL CREEKS AND STREAMS...HIGHWAYS AND UNDERPASSES. ADDITIONALLY
...COUNTRY ROADS AND FARMLANDS ALONG THE BANKS OF CREEKS AND STREAMS
AND OTHER LOW LYING AREAS ARE SUBJECT TO FLOODING.

RJK
Special weather statement, Oct 16, 11:25 AM MDT, 1 hour 50 minutes before
COZ030-032>050-170600-

SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO
NATIONAL WEATHER SERVICE DENVER COLORADO
1125 AM MDT FRI OCT 16 1998

THIS OUTLOOK PERTAINS TO THE FOLLOWING COLORADO COUNTIES

ADAMS     ARAPAHOE     BOULDER   CLEAR CREEK   DENVER       DOUGLAS
ELBERT    GILPIN       GRAND     JACKSON       JEFFERSON    LARIMER
LINCOLN   LOGAN        MORGAN    PARK          PHILLIPS     SEDGWICK
SUMMIT    WASHINGTON   WELD

SYNOPSIS:  AN APPROACHING UPPER LEVEL STORM CENTERED OVER SOUTHERN
UTAH ALONG WITH MOIST NORTHEAST UPSLOPE FLOW OVER MUCH OF NORTHEAST
COLORADO WILL CREATE AN UNSTABLE WEATHER SITUATION FOR MUCH OF
THE FORECAST AREA THIS AFTERNOON AND TONIGHT.

CURRENTLY...MODERATE SHOWERS AND A FEW THUNDERSTORMS WERE OCCURRING
ALONG THE FRONT RANGE OF WELD AND BOULDER COUNTIES.  SNOW SHOWERS
WERE ALSO SCATTERED OVER THE HIGHER AREAS OF THE REST OF LARIMER AS
WELL AS JACKSON COUNTIES.  MOIST UPSLOPE FLOW ALONG WITH ADDITIONAL
LIFT FROM THE LARGE UPPER LEVEL STORM WILL PRODUCE SCATTERED SHOWERS
AND THUNDERSTORMS OVER MOST OF THE PLAINS THIS AFTERNOON INTO THE
EVENING...WITH  SNOW SHOWERS BECOMING LIKELY IN THE ALPINE AREAS.

SEVERE WEATHER IS NOT EXPECTED...HOWEVER WITH THE FREEZING LEVELS
CONTINUING TO LOWER THROUGH THE DAY...HAIL AND OR ICE PELLETS WILL
BE A GOOD BET WITH ANY THUNDERSTORMS.  SOME MINOR FLOODING IS ALSO
POSSIBLE WITH THE HEAVIER SHOWERS.

SATURDAY'S WEATHER WILL SEE CONTINUED MOISTURE...CLOUDINESS...AND
PRECIPITATION FOR AT LEAST THE FIRST HALF OF THE DAY...WITH SLOW
IMPROVEMENT FOR THE LATER HALF.

RJK
Special weather statement, Oct 16, 11:25 AM MDT, 1 hour 50 minutes before
COZ030-032>050-170600-

SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO
NATIONAL WEATHER SERVICE DENVER COLORADO
1125 AM MDT FRI OCT 16 1998

THIS OUTLOOK PERTAINS TO THE FOLLOWING COLORADO COUNTIES

ADAMS     ARAPAHOE     BOULDER   CLEAR CREEK   DENVER       DOUGLAS
ELBERT    GILPIN       GRAND     JACKSON       JEFFERSON    LARIMER
LINCOLN   LOGAN        MORGAN    PARK          PHILLIPS     SEDGWICK
SUMMIT    WASHINGTON   WELD

SYNOPSIS:  AN APPROACHING UPPER LEVEL STORM CENTERED OVER SOUTHERN
UTAH ALONG WITH MOIST NORTHEAST UPSLOPE FLOW OVER MUCH OF NORTHEAST
COLORADO WILL CREATE AN UNSTABLE WEATHER SITUATION FOR MUCH OF
THE FORECAST AREA THIS AFTERNOON AND TONIGHT.

CURRENTLY...MODERATE SHOWERS AND A FEW THUNDERSTORMS WERE OCCURRING
ALONG THE FRONT RANGE OF WELD AND BOULDER COUNTIES.  SNOW SHOWERS
WERE ALSO SCATTERED OVER THE HIGHER AREAS OF THE REST OF LARIMER AS
WELL AS JACKSON COUNTIES.  MOIST UPSLOPE FLOW ALONG WITH ADDITIONAL
LIFT FROM THE LARGE UPPER LEVEL STORM WILL PRODUCE SCATTERED SHOWERS
AND THUNDERSTORMS OVER MOST OF THE PLAINS THIS AFTERNOON INTO THE
EVENING...WITH  SNOW SHOWERS BECOMING LIKELY IN THE ALPINE AREAS.

SEVERE WEATHER IS NOT EXPECTED...HOWEVER WITH THE FREEZING LEVELS
CONTINUING TO LOWER THROUGH THE DAY...HAIL AND OR ICE PELLETS WILL
BE A GOOD BET WITH ANY THUNDERSTORMS.  SOME MINOR FLOODING IS ALSO
POSSIBLE WITH THE HEAVIER SHOWERS.

SATURDAY'S WEATHER WILL SEE CONTINUED MOISTURE...CLOUDINESS...AND
PRECIPITATION FOR AT LEAST THE FIRST HALF OF THE DAY...WITH SLOW
IMPROVEMENT FOR THE LATER HALF.

RJK
Special weather statement, Oct 16, 12:35 PM MDT, 40 minutes before
COZ039-040-161930-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER COLORADO
1235 PM MDT FRI OCT 16 1998

...HAIL PRODUCING THUNDERSTORM OVER THE NORTHWEST DENVER METRO
AREA...

AT 1230 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
THUNDERSTORM OVER NORTHWEST JEFFERSON AND SOUTHEAST BOULDER COUNTIES.
THE STORM WAS MOVING SLOWLY EAST...ABOUT 5 MILES PER HOUR.

LITTLE RAIN WAS REPORTED WITH THIS STORM...HOWEVER SMALL...PEA.
SIZED...HAIL WAS REPORTED AND IS WAS BEGINNING TO ACCUMULATE.

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

RJK
Special weather statement, Oct 16, 12:35 PM MDT, 40 minutes before
COZ039-040-161930-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER COLORADO
1235 PM MDT FRI OCT 16 1998

...HAIL PRODUCING THUNDERSTORM OVER THE NORTHWEST DENVER METRO
AREA...

AT 1230 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
THUNDERSTORM OVER NORTHWEST JEFFERSON AND SOUTHEAST BOULDER COUNTIES.
THE STORM WAS MOVING SLOWLY EAST...ABOUT 5 MILES PER HOUR.

LITTLE RAIN WAS REPORTED WITH THIS STORM...HOWEVER SMALL...PEA.
SIZED...HAIL WAS REPORTED AND IS WAS BEGINNING TO ACCUMULATE.

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

RJK
Special weather statement, Oct 16, 12:55 PM MDT, 20 minutes before
COZ039-040-161930-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER COLORADO
1255 PM MDT FRI OCT 16 1998

...HAIL PRODUCING THUNDERSTORMS CONTINUING OVER THE NORTHWEST DENVER
METRO AREA...

AT 1255 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE THUNDERSTORMS OVER NORTHWEST JEFFERSON...SOUTHEAST
BOULDER...AND EXTREME WESTERN ADAMS COUNTY.  THE STORMS WERE MOVING
SLOWLY EAST...ABOUT 5 MILES PER HOUR.

LITTLE RAIN WAS REPORTED WITH THESE STORMS BUT SMALL PEA SIZED HAIL
HAS BEEN ACCUMULATING TO AS DEEP AS 3 INCHES IN WEST CENTRAL ARVADA.

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

RJK

The office that day

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

IssuedProductOfficeCountiesLasted
Oct 16, 1:41 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe, Denver49 min
Oct 16, 2:33 PM MDTSevere Thunderstorm WarningBOUArapahoe42 min

Nearby

Severe Thunderstorm Warnings in Colorado, 1998Every severe thunderstorm warning in 1998

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.