Alert archive / Colorado / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 162, NWS Denver/Boulder, CO

August 31, 1998Grand County, Jackson County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Aug 31, 1998, 4:08 PM MDT for Grand County, Jackson County, Colorado. It was in force for 37 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 31, 1998, 4:08 PM MDT (22:08 UTC)
Expired
Aug 31, 1998, 4:45 PM MDT
In force
37 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties

Counties Grand County, CO, Jackson County, CO

The nearest sounding before it

Grand Junction, CO (KGJT), launched 12:00Z, 10.1 hours before the alert went out and 239 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, Grand Junction, CO at 12:00Z on 1998-08-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Grand Junction, CO at 12:00Z on 1998-08-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -20 square meters per square second.193958Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3580 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
-20 m²/s²
0-3 km storm-relative helicity
-10 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

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, Aug 31, 11:30 AM MDT, 4 hours 38 minutes before
COZ030-032>050-010600-

SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO
NATIONAL WEATHER SERVICE DENVER CO
1130 AM MDT MON AUG 31 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 WEAK COLD FRONT MOVED THROUGH NORTHEAST COLORADO EARLY
THIS MORNING...WHICH HAS STABILIZED THE ATMOSPHERE FOR THE TIME
BEING ACROSS THE NORTHEAST PLAINS. BEHIND THE FRONT...UPSLOPE FLOW
WITH NORTHEAST WINDS WILL CONTINUE TO DEVELOP THIS AFTERNOON AND
CONTINUE TONIGHT. THUNDERSTORM INITIATION WILL BEGIN IN THE
MOUNTAINS AND FOOTHILLS TOWARDS MID AFTERNOON.  THUNDERSTORMS WILL
INITIALLY HAVE A HARD TIME MOVING OUT ONTO THE FRONT RANGE...HOWEVER
WITH OUTFLOW BOUNDARIES AND GREATER INSTABILITY LATER IN THE
DAY...STORMS SHOULD BEGIN TO INCREASE IN COVERAGE OVER THE FRONT
RANGE CITIES. HEAVY RAIN AND SMALL HAIL ARE LIKELY WITH THESE
STORMS...HOWEVER WOULD NOT RULE OUT AN ISOLATED SEVERE STORM WITH
LARGER HAIL UP TO 1 INCH IN DIAMETER IN THE FOOTHILLS AND NEARBY
PLAINS TOWARDS EVENING.

FURTHER EASTWARD ACROSS THE NORTHEAST PLAINS...ONLY ISOLATED SHOWERS
ARE EXPECTED THROUGH THE EARLY EVENING HOURS.

SPOTTER ACTIVATION IS NOT ANTICIPATED AS MOST OF THE STORMS WILL
REMAIN BELOW SEVERE LIMITS.

ENTREKIN
Special weather statement, Aug 31, 11:30 AM MDT, 4 hours 38 minutes before
COZ030-032>050-010600-

SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO
NATIONAL WEATHER SERVICE DENVER CO
1130 AM MDT MON AUG 31 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 WEAK COLD FRONT MOVED THROUGH NORTHEAST COLORADO EARLY
THIS MORNING...WHICH HAS STABILIZED THE ATMOSPHERE FOR THE TIME
BEING ACROSS THE NORTHEAST PLAINS. BEHIND THE FRONT...UPSLOPE FLOW
WITH NORTHEAST WINDS WILL CONTINUE TO DEVELOP THIS AFTERNOON AND
CONTINUE TONIGHT. THUNDERSTORM INITIATION WILL BEGIN IN THE
MOUNTAINS AND FOOTHILLS TOWARDS MID AFTERNOON.  THUNDERSTORMS WILL
INITIALLY HAVE A HARD TIME MOVING OUT ONTO THE FRONT RANGE...HOWEVER
WITH OUTFLOW BOUNDARIES AND GREATER INSTABILITY LATER IN THE
DAY...STORMS SHOULD BEGIN TO INCREASE IN COVERAGE OVER THE FRONT
RANGE CITIES. HEAVY RAIN AND SMALL HAIL ARE LIKELY WITH THESE
STORMS...HOWEVER WOULD NOT RULE OUT AN ISOLATED SEVERE STORM WITH
LARGER HAIL UP TO 1 INCH IN DIAMETER IN THE FOOTHILLS AND NEARBY
PLAINS TOWARDS EVENING.

FURTHER EASTWARD ACROSS THE NORTHEAST PLAINS...ONLY ISOLATED SHOWERS
ARE EXPECTED THROUGH THE EARLY EVENING HOURS.

SPOTTER ACTIVATION IS NOT ANTICIPATED AS MOST OF THE STORMS WILL
REMAIN BELOW SEVERE LIMITS.

ENTREKIN

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 31, 4:03 PM MDTSevere Thunderstorm WarningBOUGrand, Jackson42 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; the sounding from the Mesonet's radiosonde archive.