Alert archive / Colorado / Severe Thunderstorm Warnings in 2000

Severe Thunderstorm Warning 12, NWS Denver/Boulder, CO

April 24, 2000Logan County, Weld County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Apr 24, 2000, 3:07 PM MDT for Logan County, Weld County, Colorado. It was in force for 23 min. 2 reports 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
Apr 24, 2000, 3:07 PM MDT (21:07 UTC)
Expired
Apr 24, 2000, 3:30 PM MDT
In force
23 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties; the outline is the Mesonet’s reconstruction

Counties Logan County, CO, Weld County, CO

The radar

The Cheyenne radar (KCYS), 98 km from the middle of the area, began a volume at 21:06 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

TimeReportWhereRemark
Apr 24, 3:08 PM MDTHail 0.75Buckingham, CO
Apr 24, 3:12 PM MDTHail 0.75New Raymer, 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Apr 24, 12:30 PM MDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 9.1 hours before the alert went out and 101 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 2000-04-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4 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 2000-04-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 42 square meters per square second.19395878Sfc1 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
4 J/kg
Mixed-layer CIN
-167 J/kg
Mixed-layer LCL
1578 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
42 m²/s²
0-3 km storm-relative helicity
61 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.

000 
WUUS55 KBOU 242108
SVRDEN
COC075-123-242130-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DENVER CO
307 PM MDT MON APR 24 2000

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EXTREME WEST CENTRAL LOGAN COUNTY IN NORTHEAST COLORADO
  EAST CENTRAL WELD COUNTY IN NORTHEAST COLORADO

* UNTIL 330 PM MDT

* AT 307 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 9 MILES SOUTHEAST OF KEOTA...OR ABOUT 25 MILES
  NORTHWEST OF FORT MORGAN...MOVING EAST AT 45 MPH.

LOCATIONS IN THE WARNING INCLUDE...BUT ARE NOT LIMITED TO...
WILLARD...STONEHAM...PAWNEE PASS...NEW RAYMER AND KEOTA

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 4073 10409 4052 10407 4052 10346 4076 10349

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.

NWS Denver/Boulder, CO wrote its last area forecast discussion before this severe thunderstorm warning went out at Apr 24, 2:42 PM MDT, 25 minutes earlier.

Area forecast discussion, Apr 24, 2:42 PM MDT, 25 minutes before
NORTHEAST AND NORTH CENTRAL COLORADO AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER COLORADO
230 PM MDT MON APRIL 24 2000

SHORT TERM DISCUSSION: STRONG UPPER LEVEL TROUGH WORKING ITS WAY
ACROSS WESTERN PORTIONS OF CWA WHILE STRONG TO SEVERE CONVECTION
ONGOING OVER FAR EASTERN CO. LINE OF CONVECTION ACROSS LINCOLN...AND
THE FAR NERN CORNER WILL RAPIDLY MOVE OUT OF CWA LATER THIS
AFTERNOON. SOME ADDITIONAL CONVECTION HAS ALSO DEVELOPED NEAR THE
TROF AXIS ACROSS NRN WELD COUNTY. OVER THE URBAN COORIDOR...SFC
MOISTURE HAS DECREASED RAPIDLY WITH DEWPOINTS DROPPING INTO THE 20S.
ONLY EXPECT SOME SHOWERS...BUT GUSTY WINDS TO 50 MPH WITH TROF
PASSAGE AND INCREASING W-NW FLOW SURFACING DOWN FOR A TIME. THINGS
WILL REALLY QUITE DOWN THIS EVENING AS AMS DRIES AND STABILIZES FROM
WEST TO EAST. LOWS TNT A LITTLE COOLER AS SKIES CLR WITH AMS A
LITTLE COLDER. ENTREKIN

LONG TERM DISCUSSION:  DRY AND SUBSIDENT AIRMASS SHOULD BE IN PLACE
ACROSS THE CWA ON TUESDAY AS UPPER RIDGING TAKES HOLD BEHIND TODAYS
SHORT WAVE.  WILL THEREFORE REMOVE ALL POPS AND GO WITH MOSTLY SUNNY.
MODEL GRIDS AND FORECAST SOUNDINGS SUGGEST HIGHS OF 70 TO 75 ON THE
PLAINS...AND SEE NO REASON TO ARGUE.  UPPER LEVEL JET THEN BENDS
NORTHWARD INTO WYOMING FOR WEDNESDAY NIGHT AND THURSDAY...SO A
CONTINUATION OF DRY BUT EVEN WARMER WEATHER WILL PREVAIL AS MID
LEVEL THERMAL RIDGE BUILDS INTO STATE.

UPPER RIDGE CENTERS ITSELF OVER THE STATE FOR THURSDAY AND FRIDAY
WITH TEMPS REACHING THE MID 80S ON THE PLAINS BY FRIDAY.  THEN NEXT
UPPER LOW MAY DRIFT INTO THE STATE LATE SATURDAY SO WILL INCLUDE A
CHANCE OF SHOWERS AND THUNDERSTORMS AND SLIGHTLY COOLER TEMPS AT
THAT TIME.

BARJENBRUCH

.DEN...NONE.

In the hours before

Special weather statement, Apr 24, 10:30 AM MDT, 4 hours 37 minutes before
COZ030-032>050-241900-

SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO
NATIONAL WEATHER SERVICE DENVER COLORADO
1030 AM MDT MON APR 24 2000

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 ACROSS NORTHWEST
COLORADO AND WESTERN WYOMING WILL PUSH ACROSS EASTERN PORTIONS OF
COLORADO THIS AFTERNOON. SCATTERED SHOWERS HAVE ALREADY BEEN
OCCURRING AND ARE MOVING OVER HIGHER ELEVATIONS AND NORTHERN
PORTIONS OF COLORADO. AN ASSOCIATED COLD FRONT IS ALSO MOVING ACROSS
THE URBAN CORRIDOR AND WILL MOVE OVER THE NORTHEAST PLAINS THROUGH
THE MID AFTERNOON HOURS. AHEAD OF THE FRONT...ADEQUATE LOW LEVEL
MOISTURE COUPLED WITH AN UNSTABLE ATMOSPHERE WILL RESULT IN A FEW
STORMS BECOMING SEVERE BY EARLY AFTERNOON OVER THE FAR EASTERN
PLAINS OF COLORADO. THE BEST CHANCE FOR SEVERE WILL BE ALONG AND
EAST OF A LINE FROM STERLING TO AKRON AND THEN EXTENDING INTO
PHILLIPS AND SEDGWICK COUNTIES.

HAIL WILL BE THE PRIMARY THREAT WITH THESE STORMS...WITH SOME
ISOLATED REPORTS OF HAIL UP TO ONE INCH IN DIAMETER EXPECTED.
FURTHER WEST ALONG THE URBAN CORRIDOR...LOW LEVEL MOISTURE WILL
BECOME LOWER...SO BRIEF RAIN...GUSTY WINDS...AND SMALL WILL WILL BE
THE PRIMARY THREAT.

OUTLOOK FOR TUESDAY...A DRIER AND MORE STABLE ATMOSPHERE WILL MOVE
OVER THE AREA...BUT STILL AN ISOLATED STORM IS STILL POSSIBLE.
Special weather statement, Apr 24, 10:35 AM MDT, 4 hours 32 minutes before
COZ030-032>050-241900-

SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO
NATIONAL WEATHER SERVICE DENVER COLORADO
1035 AM MDT MON APR 24 2000...CORRECTION TO MIDDLE PARAGRAPH...

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 ACROSS NORTHWEST
COLORADO AND WESTERN WYOMING WILL PUSH ACROSS EASTERN PORTIONS OF
COLORADO THIS AFTERNOON. SCATTERED SHOWERS HAVE ALREADY BEEN
OCCURRING AND ARE MOVING OVER HIGHER ELEVATIONS AND NORTHERN
PORTIONS OF COLORADO. AN ASSOCIATED COLD FRONT IS ALSO MOVING ACROSS
THE URBAN CORRIDOR AND WILL MOVE OVER THE NORTHEAST PLAINS THROUGH
THE MID AFTERNOON HOURS. AHEAD OF THE FRONT...ADEQUATE LOW LEVEL
MOISTURE COUPLED WITH AN UNSTABLE ATMOSPHERE WILL RESULT IN A FEW
STORMS BECOMING SEVERE BY EARLY AFTERNOON OVER THE FAR EASTERN
PLAINS OF COLORADO. THE BEST CHANCE FOR SEVERE WILL BE ALONG AND
EAST OF A LINE FROM STERLING TO AKRON AND THEN EXTENDING INTO
PHILLIPS AND SEDGWICK COUNTIES.

HAIL WILL BE THE PRIMARY THREAT WITH THESE STORMS...WITH SOME
ISOLATED REPORTS OF HAIL UP TO ONE INCH IN DIAMETER EXPECTED.
FURTHER WEST ALONG THE URBAN CORRIDOR...LOW LEVEL MOISTURE WILL
BECOME LOWER...SO BRIEF RAIN...GUSTY WINDS...AND SMALL HAIL WILL BE
THE PRIMARY THREAT.

OUTLOOK FOR TUESDAY...A DRIER AND MORE STABLE ATMOSPHERE WILL MOVE
OVER THE AREA...BUT STILL AN ISOLATED STORM IS STILL POSSIBLE.
Local storm report, Apr 24, 1:11 PM MDT, 1 hour 56 minutes before
LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DENVER CO
111 PM MDT MON APR 24 2000

...PRELIMINARY STORM REPORT FOR APRIL 24 2000...

TIME(MDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

1205 PM    5 NE WOODLIN SCHOOL       CO   1.00 INCH HAIL
04/24/00   WASHINGTON

RAY
Local storm report, Apr 24, 2:55 PM MDT, 12 minutes before
LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DENVER CO
255 PM MDT MON APR 24 2000

...PRELIMINARY STORM REPORT FOR APRIL 24 2000...

TIME(MDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

1205 PM    5 NE WOODLIN SCHOOL       CO   1.00 INCH HAIL
04/24/00   WASHINGTON

0250 PM    5 SE BOYERO               CO   1.25 INCH HAIL
04/24/00   LINCOLN

COOPER

:

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 24, 11:50 AM MDTSevere Thunderstorm WarningBOUWashington40 min

Nearby

Severe Thunderstorm Warnings in Colorado, 2000Every severe thunderstorm warning in 2000

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.