Alert archive / Colorado / Severe Thunderstorm Warnings in 1998
Severe Thunderstorm Warning 16, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this severe thunderstorm warning at May 11, 1998, 8:27 PM MDT for Arapahoe County, Douglas County, Elbert County, Colorado. It was in force for 33 min. 1 report came from 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, with what was reported inside it.
The facts
- Issued
- May 11, 1998, 8:27 PM MDT (02:27 UTC)
- Expired
- May 11, 1998, 9:00 PM MDT
- In force
- 33 min
- Issued by
- NWS Denver/Boulder, CO
- Area
- Whole counties; the outline is the Mesonet’s reconstruction
Counties Arapahoe County, CO, Douglas County, CO, Elbert County, CO
The radar
The Denver radar (KFTG), 36 km from the middle of the area, began a volume at 02:30 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| May 11, 8:50 PM MDT | Hail 1.25 | Parker, CO |
NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.
The nearest sounding before it
Denver, CO (KDNR), launched 00:00Z, 2.5 hours before the alert went out and 136 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
- 442 J/kg
- Mixed-layer CIN
- -57 J/kg
- Mixed-layer LCL
- 2057 m above ground
- 0-6 km bulk shear
- 72 kt
- 0-1 km storm-relative helicity
- 64 m²/s²
- 0-3 km storm-relative helicity
- 212 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 2.4
The text
As transmitted, in the capitals the NWS used until 2016.
941
WUUS1 KDEN 120231 RRA
SVRDEN
COC005-035-039-120300-
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DENVER CO
827 PM MDT MON MAY 11 1998
THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A
* SEVERE THUNDERSTORM WARNING FOR...
NORTHWESTERN ELBERT COUNTY IN EAST CENTRAL COLORADO
SOUTHWESTERN ARAPAHOE COUNTY IN NORTHEAST COLORADO
NORTHEASTERN DOUGLAS COUNTY IN NORTHEAST COLORADO
* UNTIL 900 PM MDT
* AT 824 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM JUST NORTH OF PARKER...OR ABOUT 18 MILES
SOUTHEAST OF DENVER...MOVING EAST AND SOUTHEAST AT 25 MILES PER HOUR.
* LOCATIONS IN THE WARNING INCLUDE BEVERLY HILLS...ELIZABETH...
FRANKTOWN...PARKER...PONDEROSA PARK...SURREY RIDGE AND THE PINERY
THIS WARNING REPLACES THE WARNING WHICH WAS IN EFFECT FOR THE
SOUTHWEST PORTIONS OF THE DENVER AREA.
SEVERE THUNDERSTORMS CAN PRODUCE TORNADOES WITH LITTLE OR NO ADVANCE
WARNING. PREPARE TO MOVE TO A PLACE OF SAFETY IN A STURDY STRUCTURE
SUCH AS A BASEMENT OR SMALL INTERIOR ROOM IF A TORNADO IS SPOTTED.
IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER FROM THE WEATHER IN A STRONG
BUILDING. DAMAGING WIND...LARGE HAIL...VERY HEAVY RAIN...AND DEADLY
LIGHTNING ARE ALL POSSIBLE IN SEVERE THUNDERSTORMS. STAY INSIDE AWAY
FROM WINDOWS UNTIL THE STORM HAS PASSED.
ENTREKIN
LAT...LON 3959 10496 3931 10479 3933 10459 3951 10441
3964 10473What 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
Local storm report, May 11, 5:05 PM MDT, 3 hours 22 minutes before
LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DENVER CO
505 PM MDT MON MAY 11 1998
...PRELIMINARY STORM REPORT FOR MAY 10 1998...
TIME(MDT) .....CITY LOCATION.....STATE ...EVENT/REMARKS...
....COUNTY LOCATION....
0355 PM WIGGINS CO 0.75 INCH HAIL
05/10/98 MORGAN
ENTREKINLocal storm report, May 11, 5:05 PM MDT, 3 hours 22 minutes before
LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DENVER CO
505 PM MDT MON MAY 11 1998
...PRELIMINARY STORM REPORT FOR MAY 10 1998...
TIME(MDT) .....CITY LOCATION.....STATE ...EVENT/REMARKS...
....COUNTY LOCATION....
0355 PM WIGGINS CO 0.75 INCH HAIL
05/10/98 MORGAN
ENTREKINLocal storm report, May 11, 5:15 PM MDT, 3 hours 12 minutes before
LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DENVER CO
515 PM MDT MON MAY 11 1998 ...CORRECTION FOR DATE...
...PRELIMINARY STORM REPORT FOR MAY 11 1998...
TIME(MDT) .....CITY LOCATION.....STATE ...EVENT/REMARKS...
....COUNTY LOCATION....
0355 PM WIGGINS CO 0.75 INCH HAIL
05/11/98 MORGAN
ENTREKINLocal storm report, May 11, 5:15 PM MDT, 3 hours 12 minutes before
LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DENVER CO
515 PM MDT MON MAY 11 1998 ...CORRECTION FOR DATE...
...PRELIMINARY STORM REPORT FOR MAY 11 1998...
TIME(MDT) .....CITY LOCATION.....STATE ...EVENT/REMARKS...
....COUNTY LOCATION....
0355 PM WIGGINS CO 0.75 INCH HAIL
05/11/98 MORGAN
ENTREKINThe office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 11, 7:07 PM MDT | Severe Thunderstorm Warning | BOU | Lincoln | 38 min |
| May 11, 7:36 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Arapahoe, Denver | 34 min |
| May 11, 7:54 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Arapahoe, Denver, Douglas, Jefferson | 36 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.