Alert archive / Colorado / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 49, NWS Denver/Boulder, CO

May 22, 1998Washington County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at May 22, 1998, 4:40 PM MDT for Washington County, Colorado. It was in force for 50 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
May 22, 1998, 4:40 PM MDT (22:40 UTC)
Expired
May 22, 1998, 5:30 PM MDT
In force
50 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties

County Washington County, CO

The radar

The Denver radar (KFTG), 117 km from the middle of the area, began a volume at 22:43 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
May 22, 5:21 PM MDTHail 0.75Akron, 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
May 22, 1:30 PM MDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 10.7 hours before the alert went out and 11 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 1998-05-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 105 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 1998-05-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 33 square meters per square second.1939587897Sfc1 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
105 J/kg
Mixed-layer CIN
-12 J/kg
Mixed-layer LCL
747 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
33 m²/s²
0-3 km storm-relative helicity
109 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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.

In the hours before

Special weather statement, May 22, 11:24 AM MDT, 5 hours 16 minutes before
COZ036-039-040-221745-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
1124 AM MDT FRI MAY 22 1998

...STRONG THUNDERSTORMS PRODUCING HAIL IN JEFFERSON COUNTY...

AT 1108 AM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
THUNDERSTORM 4 MILES NORTH OF BERGEN PARK...OR ABOUT 20 MILES WEST OF
DENVER...MOVING NORTHEAST AT 20 MILES PER HOUR.  THIS STORM WAS
PRODUCING HEAVY RAINS AND HAIL.  THE JEFFERSON COUNTY SHERIFFS
DEPARTMENT REPORTED HAIL UP TO 5 INCHES DEEP ON INTERSTATE 70 NEAR
FLOYD HILL.

PERSONS IN OR NEAR ARVADA...EXTREME SOUTHWESTERN BROOMFIELD...
GOLDEN...NORTHWESTERN LAKEWOOD...CENTRAL WESTMINSTER...WESTERN WHEAT
RIDGE...BERGEN PARK...ELDORADO SPRINGS...EVERGREEN...KITTREDGE...
ROCKY FLATS  AND WHITE RANCH OPEN SPACE SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER AND MOVE TO A PLACE OF SAFETY IF BAD WEATHER
APPROACHES.

RJK
Special weather statement, May 22, 11:29 AM MDT, 5 hours 11 minutes before
COZ030-032>050-230600-

SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO
NATIONAL WEATHER SERVICE DENVER COLORADO
1129 AM MDT FRI MAY 22 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:  A FAIRLY MOIST...UNSTABLE...AIRMASS IS NOW IN PLACE OVER
THE FORECAST AREA.  AT THE SURFACE...DEVELOPING LOW PRESSURE OVER
SOUTHERN COLORADO WILL ALLOW AN EASTERLY COMPONENT TO THE WINDS THIS
AFTERNOON AND THIS EVENING.  THIS WILL CONTINUE TO BRING MOIST
UPSLOPE FLOW TO AREAS EAST OF THE CONTINENTAL DIVIDE.  IN THE UPPER
ATMOSPHERE...STRONG SOUTH-SOUTHWEST FLOW...A STORM SYSTEM CENTERED
JUST TO THE NORTHWEST OF COLORADO...AND COOLER AIR ALOFT WILL
PROVIDE ADDITIONAL ENHANCEMENT TO THUNDERSTORM DEVELOPMENT.  SHOWERS
AND THUNDERSTORMS ARE ALREADY DEVELOPING OVER THE FOOTHILLS...
PALMER...AND CHEYENNE RIDGES LATE THIS MORNING.  SHOWER AND
THUNDERSTORM COVERAGE SHOULD BE LIKELY THIS AFTERNOON AND EVENING
OVER MOST OF THE PLAINS AND THE FOOTHILLS OF THE FORECAST AREA.
SOME POTENTIAL FOR ISOLATED SEVERE THUNDERSTORMS EXISTS IN MOST
AREAS OF THE FLATLANDS...WITH TORNADOES...LARGE HAIL...AND HEAVY
RAINS THE THREATS.

SPOTTER ACTIVATION WILL BE REQUIRED BY 12:30 PM.      RJK
Local storm report, May 22, 2:15 PM MDT, 2 hours 25 minutes before
LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DENVER CO
215 PM MDT FRI MAY 22 1998

...PRELIMINARY STORM REPORT FOR  MAY 22 1998...

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

1237 PM    BROOMFIELD                CO   1.00 INCH HAIL
05/22/98   ADAMS

1240 PM    BROOMFIELD                CO   1.50 INCH HAIL
05/22/98   ADAMS                          HAIL COVERS GROUND

0107 PM    BRIGHTON                  CO   1.00 INCH HAIL
05/22/98   ADAMS

0142 PM    HUDSON                    CO   1.50 INCH HAIL
05/22/98   WELD

0230 PM    FT LUPTON                 CO   LIGHTNING DAMAGE
05/22/98                                  CAUSED HOUSE FIRE

0240 PM    15 N STONEHAM             CO   .88 INCH HAIL
05/22/98   WELD

HERRALD
Local storm report, May 22, 3:14 PM MDT, 1 hour 26 minutes before
LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DENVER CO
215 PM MDT FRI MAY 22 1998

...PRELIMINARY STORM REPORT FOR  MAY 22 1998...

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

1237 PM    BROOMFIELD                CO   1.00 INCH HAIL
05/22/98   ADAMS

1240 PM    BROOMFIELD                CO   1.50 INCH HAIL
05/22/98   ADAMS                          HAIL COVERS GROUND

0107 PM    BRIGHTON                  CO   1.00 INCH HAIL
05/22/98   ADAMS

0142 PM    HUDSON                    CO   1.50 INCH HAIL
05/22/98   WELD

0230 PM    FT LUPTON                 CO   LIGHTNING DAMAGE
05/22/98                                  CAUSED HOUSE FIRE

0240 PM    15 N STONEHAM             CO   .88 INCH HAIL
05/22/98   WELD

HERRALD

The office that day

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

IssuedProductOfficeCountiesLasted
May 21, 6:13 PM MDTTornado WarningBOUPhillips, Sedgwick22 min
May 21, 6:15 PM MDTSevere Thunderstorm WarningBOULogan45 min
May 21, 7:27 PM MDTSevere Thunderstorm WarningBOUMorgan, Weld33 min
May 21, 8:01 PM MDTSevere Thunderstorm WarningBOUMorgan, Weld39 min
May 21, 8:55 PM MDTSevere Thunderstorm WarningBOULogan, Phillips35 min
May 21, 10:36 PM MDTSevere Thunderstorm WarningBOUAdams, Weld34 min
May 22, 11:56 AM MDTSevere Thunderstorm WarningBOUBoulder, Jefferson34 min
May 22, 12:29 PM MDTSevere Thunderstorm WarningBOUBoulder, Jefferson, Weld46 min
May 22, 12:29 PM MDTSevere Thunderstorm WarningBOUAdams46 min
May 22, 1:00 PM MDTSevere Thunderstorm WarningBOUAdams, Weld30 min
May 22, 1:10 PM MDTSevere Thunderstorm WarningBOUBoulder, Larimer, Weld25 min
May 22, 1:30 PM MDTSevere Thunderstorm WarningBOUAdams, Weld45 min
May 22, 1:35 PM MDTSevere Thunderstorm WarningBOULarimer, Weld40 min
May 22, 1:41 PM MDTSevere Thunderstorm WarningBOUWeld34 min
May 22, 2:06 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe, Denver39 min
May 22, 2:15 PM MDTSevere Thunderstorm WarningBOUMorgan, Weld45 min
May 22, 2:21 PM MDTSevere Thunderstorm WarningBOUWeld24 min
May 22, 2:45 PM MDTSevere Thunderstorm WarningBOUMorgan, Weld45 min
May 22, 2:58 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe32 min
May 22, 3:15 PM MDTSevere Thunderstorm WarningBOUMorgan, Weld40 min
May 22, 3:21 PM MDTTornado WarningBOUAdams, Arapahoe24 min
May 22, 3:55 PM MDTSevere Thunderstorm WarningBOUMorgan, Washington35 min
May 22, 4:11 PM MDTSevere Thunderstorm WarningBOUAdams34 min
May 22, 4:30 PM MDTSevere Thunderstorm WarningBOULogan, Morgan, Washington30 min
May 22, 4:46 PM MDTSevere Thunderstorm WarningBOUAdams, Washington44 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.