Alert archive / Arizona / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 94, NWS Las Vegas, NV

October 21, 1997Mohave County, Arizona

NWS Las Vegas, NV issued this severe thunderstorm warning at Oct 21, 1997, 10:20 PM MST for Mohave County, Arizona. It was in force for 55 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
Oct 21, 1997, 10:20 PM MST (05:20 UTC)
Expired
Oct 21, 1997, 11:15 PM MST
In force
55 min
Issued by
NWS Las Vegas, NV
Area
Whole counties

County Mohave County, AZ

The nearest sounding before it

Flgstf/Belemont, AZ (KFGZ), launched 00:00Z, 5.3 hours before the alert went out and 185 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, Flgstf/Belemont, AZ at 00:00Z on 1997-10-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 14 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, Flgstf/Belemont, AZ at 00:00Z on 1997-10-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 32 square meters per square second.1939Sfc1 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
14 J/kg
Mixed-layer CIN
-78 J/kg
Mixed-layer LCL
2048 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
32 m²/s²
0-3 km storm-relative helicity
48 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 
TTAA00 KLAS 220522 RRA
SVRLAS
AZC015-220615-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
1020 PM PDT (1020 PM MST) TUE OCT 21 1997
 
THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 1115 PM PDT (1115 PM MST)
FOR PEOPLE IN THE FOLLOWING LOCATIONS......
 
IN NORTHWEST ARIZONA
 
   ...SOUTHERN MOHAVE COUNTY
 
LAS VEGAS DOPPLER RADAR SHOWED A SEVERE THUNDERSTORM 10 MILES SOUTHEAST
OF LAKE HAVASU CITY. THIS STORM WAS MOVING TOWARD THE NORTHWEST AT 25
MPH AND WILL AFFECT THE LAKE HAVASU CITY AREA WITHIN THE NEXT 30
MINUTES.
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55
MPH...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN.
FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR
OF YOUR HOME OR BUSINESS.  HEAVY RAINS FLOOD ROADS QUICKLY SO
DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.
 
MATUSIEWICZ/MAKER

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 Las Vegas, NV wrote its last area forecast discussion before this severe thunderstorm warning went out at Oct 21, 9:05 PM MST, 1 hour 15 minutes earlier.

Area forecast discussion, Oct 21, 9:05 PM MST, 1 hour 15 minutes before
MOJAVE DESERT/SOUTHERN GREAT BASIN AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
845 PM PDT TUE OCT 21 1997

WATER VAPOR LOOP THIS EVE SHOWED AN UPR LOW ACRS SRN CALIFORNIA
DROPPING SEWD. PLENTY OF MID LVL MSTR WAS BEING DRAWN N THEN NW INTO
THIS SYS ACRS ERN ARIZONA THEN BACK ACROSS PTNS OF NW ARIZONA...SRN
NEVADA AND SRN CALIFORNIA. KESX RADAR SHOWED STG THUNDERSTORMS DVLPG
ACRS EXTREME SRN PTNS OF THE CWA NEAR LAKE HAVASU CITY AND ADJOINING
AREAS OF SE CALIFORNIA. THESE AREAS LOOK PRIME FOR TRW ACTIVITY AT
LEAST THE NEXT FEW HOURS AS 00Z ETA PROGGED CAPES AROUND 600 AND
LIFTED INDICES TO -6 ACRS THIS AREA AT 06Z. FARTHER N...ACRS CNTRL
MOHAVE COUNTY IN ARIZONA W ACRS CLARK COUNTY IN NEVADA...MAY SEE A
STRAY RW/TRW TIL MIDNIGHT. DRY NRLY FLO HAD BUILT IN ACRS NRN PTNS OF
THE CWA. THIS WL CONT THRU THE OVERNIGHT HOURS. 00Z MDLS SHOWED THE
UPR LOW MOVING INTO SE ARIZONA BY TOMORROW AFTN WITH A DRIER NW FLO
BUILDING ACRfS THE CWA. MADE FIRST PD CHANGES ACRS SRN NEVADA ZNS.
RMNDR OF CURRENT FSCT PACKAGE LOOKED FINE. LAS 1000. MATUSIEWICZ

SRN NV...NONE
ERN CA...NONE
NW AZ...NONE

Nearby

Severe Thunderstorm Warnings in Arizona, 1997Every severe thunderstorm warning in 1997

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.