Alert archive / Colorado / Severe Thunderstorm Warnings in 1998
Severe Thunderstorm Warning 86, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this severe thunderstorm warning at Jun 9, 1998, 4:35 PM MDT for Larimer County, Weld County, Colorado. It was in force for 40 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
- Jun 9, 1998, 4:35 PM MDT (22:35 UTC)
- Expired
- Jun 9, 1998, 5:15 PM MDT
- In force
- 40 min
- Issued by
- NWS Denver/Boulder, CO
- Area
- Whole counties; the outline is the Mesonet’s reconstruction
Counties Larimer County, CO, Weld County, CO
The radar
The Denver radar (KFTG), 78 km from the middle of the area, began a volume at 22:35 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, 10.6 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.
- Mixed-layer CAPE
- 30 J/kg
- Mixed-layer CIN
- -98 J/kg
- Mixed-layer LCL
- 647 m above ground
- 0-6 km bulk shear
- 42 kt
- 0-1 km storm-relative helicity
- 60 m²/s²
- 0-3 km storm-relative helicity
- 161 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
493
WUUS1 KDEN 092236 RRA
SVRDEN
COC069-123-092315-
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DENVER CO
435 PM MDT TUE JUN 9 1998
THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A
* SEVERE THUNDERSTORM WARNING FOR...
EXTREME SOUTHEASTERN LARIMER COUNTY IN NORTH CENTRAL COLORADO
WEST CENTRAL WELD COUNTY IN NORTHEAST COLORADO
* UNTIL 515 PM MDT
* AT 429 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM 2 MILES EAST OF LOVELAND...OR ABOUT 14
MILES SOUTH OF FORT COLLINS...MOVING NORTHEAST AT 20 MILES PER
HOUR.
* LOCATIONS IN THE WARNING INCLUDE...SEVERANCE AND WINDSOR
VERY LARGE HAIL IS POSSIBLE WITH THIS SEVERE THUNDERSTORM. IF YOU ARE
IN THE PATH OF THE STORM...PUT YOUR CAR IN A GARAGE AND MOVE TO A
SUBSTANTIAL SHELTER.
LAT...LON 4044 10505 4034 10508 4033 10475 4057 10475
BARJENBRUCHWhat 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, Jun 9, 11:15 AM MDT, 5 hours 20 minutes before
COZ030-032>050-100600- SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO NATIONAL WEATHER SERVICE DENVER CO 1115 AM MDT TUE JUN 09 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 UPPER LEVEL LOW PRESSURE SYSTEM WILL BE APPROACHING THE OUTLOOK AREA TODAY...MAKING CONDITIONS FAVORABLE FOR THUNDERSTORM DEVELOPMENT. IN FACT AS OF 11 AM SHOWERS AND THUNDERSTORMS WERE ALREADY WELL UNDERWAY IN MANY OF THE MOUNTAIN COUNTIES. THESE MOUNTAIN THUNDERSTORMS WILL CONTINUE THROUGH THE AFTERNOON AND INTO THE EVENING HOURS. ON THE PLAINS...THINGS ARE A BIT MORE COMPLICATED. IT APPEARS A SURE BET THAT STORMS THAT DEVELOPING OVER THE MOUNTAINS WILL MOVE INTO THE URBAN CORRIDOR BY 1 PM OR SO...DEVELOPING FURTHER EAST THEREAFTER. HOW STRONG THEY BECOME IS SOMEWHAT OF A QUESTION STILL AS MOISTURE IS NOT TREMENDOUSLY ABUNDANT. THE AIRMASS OVER THE PLAINS WILL BE MODERATELY UNSTABLE DURING THE AFTERNOON AND EVENING HOURS. THIS INSTABILITY WILL COUPLE WITH A RESPECTABLE WINDS ALOFT TO PRODUCE CONDITIONS FAVORABLE FOR AT LEAST A FEW STRONG TO SEVERE THUNDERSTORMS. ROTATING THUNDERSTORMS ARE ALSO A POSSIBILITY ON THE PLAINS...ESPECIALLY IN AREAS EAST OF THE URBAN CORRIDOR...WHERE AN ISOLATED TORNADO IS NOT OUT OF THE QUESTION. AS THE SURFACE WINDS INCREASE SOME THIS AFTERNOON...A DENVER CYCLONE MAY DEVELOP WHICH COULD INCREASE THE LIKELIHOOD OF STRONGER STORMS IN AT LEAST THE SOUTHERN PORTIONS OF THE URBAN CORRIDOR BY MID AFTERNOON. LASTLY...AS THE UPPER LEVEL SYSTEM APPROACHES FROM THE WEST...SOME OF THE STORMS MAY LAST LONGER INTO THE EVENING...ESPECIALLY IN NORTHEAST WELD...LOGAN...SEDGWICK AND PHILLIPS COUNTIES. SPOTTER ACTIVATION MAY BE NECESSARY BY 130 PM. ET
Special weather statement, Jun 9, 11:15 AM MDT, 5 hours 20 minutes before
COZ030-032>050-100600- SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO NATIONAL WEATHER SERVICE DENVER CO 1115 AM MDT TUE JUN 09 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 UPPER LEVEL LOW PRESSURE SYSTEM WILL BE APPROACHING THE OUTLOOK AREA TODAY...MAKING CONDITIONS FAVORABLE FOR THUNDERSTORM DEVELOPMENT. IN FACT AS OF 11 AM SHOWERS AND THUNDERSTORMS WERE ALREADY WELL UNDERWAY IN MANY OF THE MOUNTAIN COUNTIES. THESE MOUNTAIN THUNDERSTORMS WILL CONTINUE THROUGH THE AFTERNOON AND INTO THE EVENING HOURS. ON THE PLAINS...THINGS ARE A BIT MORE COMPLICATED. IT APPEARS A SURE BET THAT STORMS THAT DEVELOPING OVER THE MOUNTAINS WILL MOVE INTO THE URBAN CORRIDOR BY 1 PM OR SO...DEVELOPING FURTHER EAST THEREAFTER. HOW STRONG THEY BECOME IS SOMEWHAT OF A QUESTION STILL AS MOISTURE IS NOT TREMENDOUSLY ABUNDANT. THE AIRMASS OVER THE PLAINS WILL BE MODERATELY UNSTABLE DURING THE AFTERNOON AND EVENING HOURS. THIS INSTABILITY WILL COUPLE WITH A RESPECTABLE WINDS ALOFT TO PRODUCE CONDITIONS FAVORABLE FOR AT LEAST A FEW STRONG TO SEVERE THUNDERSTORMS. ROTATING THUNDERSTORMS ARE ALSO A POSSIBILITY ON THE PLAINS...ESPECIALLY IN AREAS EAST OF THE URBAN CORRIDOR...WHERE AN ISOLATED TORNADO IS NOT OUT OF THE QUESTION. AS THE SURFACE WINDS INCREASE SOME THIS AFTERNOON...A DENVER CYCLONE MAY DEVELOP WHICH COULD INCREASE THE LIKELIHOOD OF STRONGER STORMS IN AT LEAST THE SOUTHERN PORTIONS OF THE URBAN CORRIDOR BY MID AFTERNOON. LASTLY...AS THE UPPER LEVEL SYSTEM APPROACHES FROM THE WEST...SOME OF THE STORMS MAY LAST LONGER INTO THE EVENING...ESPECIALLY IN NORTHEAST WELD...LOGAN...SEDGWICK AND PHILLIPS COUNTIES. SPOTTER ACTIVATION MAY BE NECESSARY BY 130 PM. ET
The office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 8, 6:00 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Arapahoe | 45 min |
| Jun 8, 6:43 PM MDT | Severe Thunderstorm Warning | BOU | Arapahoe, Elbert | 47 min |
| Jun 8, 7:30 PM MDT | Severe Thunderstorm Warning | BOU | Douglas, Elbert | 45 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.