Alert archive / Colorado / Severe Thunderstorm Warnings in 1998
Severe Thunderstorm Warning 159, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this severe thunderstorm warning at Aug 21, 1998, 3:17 PM MDT for Douglas County, Elbert County, Colorado. It was in force for 43 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
- Aug 21, 1998, 3:17 PM MDT (21:17 UTC)
- Expired
- Aug 21, 1998, 4:00 PM MDT
- In force
- 43 min
- Issued by
- NWS Denver/Boulder, CO
- Area
- Whole counties; the outline is the Mesonet’s reconstruction
Counties Douglas County, CO, Elbert County, CO
The radar
The Denver radar (KFTG), 32 km from the middle of the area, began a volume at 21:16 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, 9.3 hours before the alert went out and 120 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 2002 m above ground
- 0-6 km bulk shear
- 4 kt
- 0-1 km storm-relative helicity
- 21 m²/s²
- 0-3 km storm-relative helicity
- -22 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
883
WUUS1 KDEN 212119 RRA
SVRDEN
COC035-039-212200-
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DENVER CO
317 PM MDT FRI AUG 21 1998
THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A
* SEVERE THUNDERSTORM WARNING FOR...
NORTHWESTERN ELBERT COUNTY IN EAST CENTRAL COLORADO
NORTHEASTERN DOUGLAS COUNTY IN NORTHEAST COLORADO
* UNTIL 400 PM MDT
* AT 316 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM 3 MILES NORTHEAST OF THE PINERY...OR ABOUT
28 MILES SOUTHEAST OF DENVER...MOVING EAST AT 15 MILES PER HOUR.
LARGE HAIL UP TO 1 INCH IN DIAMETER 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. HEAVY RAINS WITH THIS
STORM WILL FLOOD ROADS QUICKLY. DO NOT DRIVE THROUGH FLOODED AREAS.
LAT...LON 3955 10467 3944 10468 3941 10433 3956 10442
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, Aug 21, 10:45 AM MDT, 4 hours 32 minutes before
COZ030-032>050-220600- SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO NATIONAL WEATHER SERVICE DENVER CO 1045 AM MDT FRI AUG 21 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 RIDGE OF HIGH PRESSURE OVER THE GREAT PLAINS WILL CONTINUE TO ALLOW TROPICAL MONSOONAL MOISTURE TO STREAM ACROSS COLORADO THIS AFTERNOON AND TONIGHT. AN UPPER LEVEL DISTURBANCE EMBEDDED IN THE MOIST FLOW WILL MOVE ACROSS THE AREA TONIGHT. THIS WILL ENHANCE THE FORMATION OF CONVECTIVE STORMS WELL INTO THE NIGHT. SCATTERED SHOWERS AND THUNDERSTORMS WILL AGAIN MOVE OFF THE MOUNTAINS AND EASTERN FOOTHILLS THIS AFTERNOON AND SPREAD OVER THE EASTERN PLAINS LATE THIS AFTERNOON AND TONIGHT. DUE TO RELATIVELY LIGHT WINDS ALOFT AND HIGH PRECIPITIBLE WATERS THE STORMS WILL LIKELY PRODUCE LOCALLY HEAVY RAINFALL. MAXIMUM POSSIBLE THUNDERSTORM RAINFALL MAY TOTAL BETWEEN 2 AND 3 INCHES. THIS AMOUNT OF RAIN MAY CAUSE SMALL STREAM FLOODING AND URBAN STREET FLOODING. A HIGH FREEZING LEVEL SHOULD KEEP HAIL SIZE SMALL. MOST STORMS WILL NOT BE SEVERE BUT ONE OR TWO MAY PRODUCE STRONG GUSTY WINDS ABOVE SEVERE THUNDERSTORM WIND CRITERIA OF 58 MPH. SPOTTER ACTIVATION WILL NOT BE REQUIRED...BUT SIGNIFICANT RAINFALL OR FLOODING REPORTS WOULD BE GREATLY APPRECIATED. GARD...WSFO DENVER
Special weather statement, Aug 21, 10:45 AM MDT, 4 hours 32 minutes before
COZ030-032>050-220600- SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO NATIONAL WEATHER SERVICE DENVER CO 1045 AM MDT FRI AUG 21 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 RIDGE OF HIGH PRESSURE OVER THE GREAT PLAINS WILL CONTINUE TO ALLOW TROPICAL MONSOONAL MOISTURE TO STREAM ACROSS COLORADO THIS AFTERNOON AND TONIGHT. AN UPPER LEVEL DISTURBANCE EMBEDDED IN THE MOIST FLOW WILL MOVE ACROSS THE AREA TONIGHT. THIS WILL ENHANCE THE FORMATION OF CONVECTIVE STORMS WELL INTO THE NIGHT. SCATTERED SHOWERS AND THUNDERSTORMS WILL AGAIN MOVE OFF THE MOUNTAINS AND EASTERN FOOTHILLS THIS AFTERNOON AND SPREAD OVER THE EASTERN PLAINS LATE THIS AFTERNOON AND TONIGHT. DUE TO RELATIVELY LIGHT WINDS ALOFT AND HIGH PRECIPITIBLE WATERS THE STORMS WILL LIKELY PRODUCE LOCALLY HEAVY RAINFALL. MAXIMUM POSSIBLE THUNDERSTORM RAINFALL MAY TOTAL BETWEEN 2 AND 3 INCHES. THIS AMOUNT OF RAIN MAY CAUSE SMALL STREAM FLOODING AND URBAN STREET FLOODING. A HIGH FREEZING LEVEL SHOULD KEEP HAIL SIZE SMALL. MOST STORMS WILL NOT BE SEVERE BUT ONE OR TWO MAY PRODUCE STRONG GUSTY WINDS ABOVE SEVERE THUNDERSTORM WIND CRITERIA OF 58 MPH. SPOTTER ACTIVATION WILL NOT BE REQUIRED...BUT SIGNIFICANT RAINFALL OR FLOODING REPORTS WOULD BE GREATLY APPRECIATED. GARD...WSFO DENVER
The office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 21, 4:19 PM MDT | Flash Flood Warning | BOU | Arapahoe, Douglas, Elbert | 3 hr |
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.