Alert archive / Colorado / Tornado Warnings in 1999
Tornado Warning 26, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this tornado warning at Jun 11, 1999, 1:50 PM MDT for Elbert County, Colorado. It was in force for 25 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 11, 1999, 1:50 PM MDT (19:50 UTC)
- Expired
- Jun 11, 1999, 2:15 PM MDT
- In force
- 25 min
- Issued by
- NWS Denver/Boulder, CO
- Area
- Whole counties; the outline is the Mesonet’s reconstruction
County Elbert County, CO
The radar
The Denver radar (KFTG), 45 km from the middle of the area, began a volume at 20:03 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 watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Jun 11, 1:15 PM MDT | Severe Thunderstorm Watch | SPC | 7 hr |
The nearest sounding before it
Denver, CO (KDNR), launched 12:00Z, 7.8 hours before the alert went out and 131 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
- 14 J/kg
- Mixed-layer CIN
- -267 J/kg
- Mixed-layer LCL
- 806 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- 27 m²/s²
- 0-3 km storm-relative helicity
- 197 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
639 WFUS1 KDEN 111952 RRA TORDEN COC039-112015- BULLETIN - EAS ACTIVATION REQUESTED TORNADO WARNING NATIONAL WEATHER SERVICE DENVER CO 150 PM MDT FRI JUN 11 1999 THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A * TORNADO WARNING FOR... EXTREME WEST CENTRAL ELBERT COUNTY IN EAST CENTRAL COLORADO * UNTIL 215 PM MDT * AT 144 PM MDT...AMATEUR RADIO WEATHER SPOTTERS REPORTED A TORNADO 3 MILES SOUTHWEST OF PONDEROSA PARK...OR ABOUT 31 MILES SOUTHEAST OF DENVER...MOVING EAST AT 10 MPH. LOCATIONS IN THE WARNING INCLUDE...BUT ARE NOT LIMITED TO...PONDEROSA PARK AND ELIZABETH THE SAFEST PLACE TO BE DURING A TORNADO IS IN A BASEMENT. GET UNDER A WORKBENCH OR OTHER PIECE OF STURDY FURNITURE. IF NO BASEMENT IS AVAILABLE...SEEK SHELTER ON THE LOWEST FLOOR OF THE BUILDING IN AN INTERIOR HALLWAY OR ROOM SUCH AS A CLOSET. USE BLANKETS OR PILLOWS TO COVER YOUR BODY AND ALWAYS STAY AWAY FROM WINDOWS. IF IN MOBILE HOMES OR VEHICLES...EVACUATE THEM AND GET INSIDE A SUBSTANTIAL SHELTER. IF NO SHELTER IS AVAILABLE...LIE FLAT IN THE NEAREST DITCH OR OTHER LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS. LAT...LON 3942 10458 3938 10469 3934 10467 3935 10456 GIMMESTAD &
What forecasters said that day
The local office's own words before this tornado warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Denver/Boulder, CO wrote its last area forecast discussion before this tornado warning went out at Jun 11, 2:49 AM MDT, 11 hours 1 minute earlier.
Area forecast discussion, Jun 11, 2:49 AM MDT, 11 hours 1 minute before
NORTHEAST AND NORTH CENTRAL COLORADO AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DENVER COLORADO 3 AM MDT FRIDAY JUNE 11 1999 APPEARS ALL THE INGREDIENTS STILL AVBL TO CAUSE AT LEAST TWO MORE DAYS OF VERY ACTIVE WX OVER NERN CO. PLENTY OF MSTR AVBL WITH RH IN THE 60-70 PRCNT RANGE AND PCPBL H20 RANGING FROM .5 TO .8 INCH DEPENDING ON MODEL AND TIME OF DAY. THETA-E RDG SHUD REMAIN OVER ERN CO THRU SAT AS WELL SO ONLY NEED TO ADD SOME INSTBY AND LIFT. INSTBY SHUD BE NO PRBLM AS AMS TO HEAT FASTER DUE INCREASED SOLAR INSOLATION ALONG FRONT RANGE WHERE SHUD BE LESS CLOUDS THAN THURS MRNG. ON OTHER HAND RESIDUAL CLOUDS AND AREAS OF FOG WILL HINDER WARMING FURTHER E HWVR W-SW FLOW ALF IN PLACE THUS ANY TSTMS THAT FIRES NEAR FTHLS SHUD EVENTUALLY REACH ERN ZONES ALTHO MAY NOT BE TIL NEAR SUNDOWN. LIFT WILL BE PROVIDED BY 2 MECHANISMS. FIRST WILL BE CONTD E-SE LOW LVL FLOW WHICH SHUD PROVIDE LIFT ALG FTHLS. SECOND IS WEAK SHT WV WHICH MODELS SHOW MOVING IN FROM SOCAL/BAJA AREA WITH ETA BEING JUST LITTLE FASTER THAN OTHER MDLS AND PROBLY LITTLE BETTER TIMING FROM WATER VAPOR LOOP. AFTN/EVE SHIFTS SHUD BE HUMMING AGAIN WITH SEVERE TSTMS PSBL AND PERHAPS SOME TORNADIC ACVTY SINCE PROGD SOUNDINGS INDCT CAPES APCHG 1500 JOULES. SHEAR IS WEAK EVEN THOUGH ITS FVRBL WITH SELY FLOW LOWER ATMOS AND W-SW FLOW ALF. WITH PCPBL H2O OVER 1/2 INCH CUD SEE SOME HVY RAIN AND LOCAL FLOODING PSBL ESPCLY IN AREAS WHERE HVY RAIN OCCURRED THURS AFTN/EVE. DO NOT SEE ANY SUBSTANTIAL CHNG TO PTRN FOR SAT SO CUD BE ANOTHER ROUND OF WET HEAVY WX THEN AS WELL. WITH THIS IN MIND SEE NO REASON WILL NOT HAVE PCPN THIS AFTN IN NERN CO THRFR WILL BOOST POPS INTO LIKELY RANGE FOR THIS AFTN/EVE BUT BE LITTLE MORE CONSERVATIVE FOR SAT WITH SCT POPS SINCE NEXT SHT WV MAY BE FRTHR S IN NM. EXPECT MORE SUNSHINE ALG FRONT RANGE THIS MRNG AND WILL BOOST TODAYS HIGHS FEW DEGS ABOVE THURS READINGS AND SPLIT DFRNC BTWN FWC AND FAN GDNC TODAY WITH LTL CHNG TMW. AS FOR LONG TERM PICTURE SEE NO REASON TO REMOVE THREAT OF AFTN/EVE TSTMS SNC MRF SHOWS LITTLE CHANGE IN PTRN THRU WED. MEAN RH TO BE 50 PRCNT OR HIER AND WEAK UPSLP GRAD OVER ERN CO AS SFC LOW PRES CONTS OVER UT...AZ AND NM WITH HIER PRES OVER PLAINS THRU MIDWEEK. AMS MAY STBLZ SOMEWHAT WITH RDG BECMG MORE PRONOUNCED OVER WRN U.S. AND NW FLOW ALF TO PREVAIL OVER CO BUT THIS MAY HAVE GREATER IMPACT ON MTNS THAN PLAINS ZONES. RUBBLE .DEN...NONE.
In the hours before
Special weather statement, Jun 11, 11:15 AM MDT, 2 hours 35 minutes before
COZ030-032>050-120600- SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO NATIONAL WEATHER SERVICE DENVER CO 1115 AM MDT FRI JUN 11 1999 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: SUFFICIENT LOW LEVEL MOISTURE REMAINS ACROSS THE FOOTHILLS AND PLAINS OF NORTHEAST COLORADO...WHILE AMPLE HEATING WILL ALLOW THE ATMOSPHERE TO BECOME STRONGLY UNSTABLE THIS AFTERNOON AND INTO THE EVENING. THERE WILL BE SOME ENERGY AVAILABLE IN THE UPPER LEVELS TO ENHANCE STORM DEVELOPMENT LATER THIS AFTERNOON AND EVENING. AT THIS TIME...WIND FLOW PATTERNS ARE NOT CONDUCIVE TO TORNADIC DEVELOPMENT... BUT LARGE HAIL IS POSSIBLE WITH STORMS TODAY. INITIAL DEVELOPMENT WILL AGAIN DEVELOP OVER THE MOUNTAINS AND FOOTHILLS BY NOON AND GRADUALLY MOVE OVER THE URBAN CORRIDOR DURING THE EARLY AFTERNOON AND LATE AFTERNOON AND EARLY EVENING OVER THE PLAINS. THE ATMOSPHERE IS A LITTLE DRIER OVER THE WYOMING AND COLORADO BORDER AREAS...INCLUDING THE FAR NORTHERN MOUNTAINS AND FOOTHILLS OF LARIMER COUNTY...AND EXTENDING OUT INTO WELD COUNTY. STORMS WILL BE LATER IN DEVELOPING AND WEAKER OVER THESE AREAS. SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON AND EVENING...MAINLY AFTER 2 PM. ENTREKIN
Special weather statement, Jun 11, 11:15 AM MDT, 2 hours 35 minutes before
COZ030-032>050-120600- SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO NATIONAL WEATHER SERVICE DENVER CO 1115 AM MDT FRI JUN 11 1999 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: SUFFICIENT LOW LEVEL MOISTURE REMAINS ACROSS THE FOOTHILLS AND PLAINS OF NORTHEAST COLORADO...WHILE AMPLE HEATING WILL ALLOW THE ATMOSPHERE TO BECOME STRONGLY UNSTABLE THIS AFTERNOON AND INTO THE EVENING. THERE WILL BE SOME ENERGY AVAILABLE IN THE UPPER LEVELS TO ENHANCE STORM DEVELOPMENT LATER THIS AFTERNOON AND EVENING. AT THIS TIME...WIND FLOW PATTERNS ARE NOT CONDUCIVE TO TORNADIC DEVELOPMENT... BUT LARGE HAIL IS POSSIBLE WITH STORMS TODAY. INITIAL DEVELOPMENT WILL AGAIN DEVELOP OVER THE MOUNTAINS AND FOOTHILLS BY NOON AND GRADUALLY MOVE OVER THE URBAN CORRIDOR DURING THE EARLY AFTERNOON AND LATE AFTERNOON AND EARLY EVENING OVER THE PLAINS. THE ATMOSPHERE IS A LITTLE DRIER OVER THE WYOMING AND COLORADO BORDER AREAS...INCLUDING THE FAR NORTHERN MOUNTAINS AND FOOTHILLS OF LARIMER COUNTY...AND EXTENDING OUT INTO WELD COUNTY. STORMS WILL BE LATER IN DEVELOPING AND WEAKER OVER THESE AREAS. SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON AND EVENING...MAINLY AFTER 2 PM. ENTREKIN
The office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 10, 6:00 PM MDT | Tornado Warning | BOU | Adams, Arapahoe, Washington | 30 min |
| Jun 10, 6:23 PM MDT | Tornado Warning | BOU | Washington | 37 min |
| Jun 10, 6:59 PM MDT | Tornado Warning | BOU | Washington | 31 min |
| Jun 10, 7:28 PM MDT | Severe Thunderstorm Warning | BOU | Washington | 47 min |
| Jun 11, 1:01 PM MDT | Severe Thunderstorm Warning | BOU | Douglas, Elbert | 44 min |
| Jun 11, 1:42 PM MDT | Severe Thunderstorm Warning | BOU | Douglas, Elbert | 48 min |
| Jun 11, 2:26 PM MDT | Severe Thunderstorm Warning | BOU | Arapahoe, Douglas | 34 min |
| Jun 11, 2:36 PM MDT | Severe Thunderstorm Warning | BOU | Douglas, Elbert | 39 min |
| Jun 11, 2:54 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Arapahoe, Denver | 51 min |
| Jun 11, 3:14 PM MDT | Severe Thunderstorm Warning | BOU | Elbert | 46 min |
Nearby
Tornado Warnings in Colorado, 1999Every tornado warning in 1999Tornadoes in 1999
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.