Alert archive / Arizona / Severe Thunderstorm Warnings in 1998
Severe Thunderstorm Warning 7, NWS Las Vegas, NV
NWS Las Vegas, NV issued this severe thunderstorm warning at Jul 20, 1998, 7:07 PM MST for Mohave County, Arizona. It was in force for 58 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
- Jul 20, 1998, 7:07 PM MST (02:07 UTC)
- Expired
- Jul 20, 1998, 8:05 PM MST
- In force
- 58 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, 2.1 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.
- Mixed-layer CAPE
- 534 J/kg
- Mixed-layer CIN
- -46 J/kg
- Mixed-layer LCL
- 1738 m above ground
- 0-6 km bulk shear
- 16 kt
- 0-1 km storm-relative helicity
- -12 m²/s²
- 0-3 km storm-relative helicity
- 85 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KLAS 210209 RRA SVRLAS AZC015-210305- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE LAS VEGAS NV 707 PM PDT (707 PM MST) MON JUL 20 1998 * SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL MOHAVE COUNTY IN NORTHWESTERN ARIZONA * UNTIL 805 PM MST (805 PM PDT) * SOME LOCATIONS AFFECTED PEACH SPRINGS TRUXTON HUALAPAUI INDIAN RESERVATION AT 700 PM...DOPPLER RADAR DETECTED A SEVERE THUNDERSTORM NEAR THE MOHAVE/COCONINO COUNTY LINE. MOVEMENT WAS TO THE WEST AT 15 MPH. A HAM RADIO SPOTTER EAST OF PEACH SPRINGS REPORTED WIND GUSTS TO 50 MPH. STRONG DAMAGING WINDS ARE LIKELY WITH THIS STORM. IF YOU ARE OUTDOORS...MOVE TO A PLACE OF SHELTER IMMEDIATELY IF A STORM APPROACHES. MOTORISTS SHOULD REMAIN ALERT FOR REDUCED VISIBILITIES DURING DOWNPOURS OF RAIN. STREETS MAY FLOOD QUICKLY. PIERCE
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 Jul 20, 1:50 PM MST, 5 hours 17 minutes earlier.
Area forecast discussion, Jul 20, 1:50 PM MST, 5 hours 17 minutes before
MOJAVE DESERT/SOUTHERN GREAT BASIN AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LAS VEGAS NV 150 PM PDT MON JUL 20 1998 SYNOPSIS...THE UPPER LEVEL HIGH PRESSURE SYSTEM OVER SOUTHEAST UTAH WILL MOVE VERY LITTLE THROUGH TUESDAY. THIS WILL ALLOW FOR MONSOONAL MOISTURE TO FLOW NORTHWESTWARD ACROSS THE MOJAVE DESERT AND SOUTHERN GREAT BASIN CONTINUING THE CHANCE OF LATE DAY THUNDERSTORMS. DISCUSSION...UPPER RIDGE THAT HAS BEEN DOMINATE ACROSS THE AREA THE LAST FEW DAYS HAD SHIFTED EAST TOWARD THE FOUR CORNERS AREA. THIS HAS ALLOWED THE MOIST MONSOONAL FLOW TO SURGE NORTH INTO THE CWA. LOW LEVEL MOISTURE HAD INCREASED...WITH LOW LEVEL DEWPOINTS INTO THE 50S ACROSS THE NORTH AND 60S ACROSS THE SOUTH. CIRCULATION CENTER FROM AN EARLY MORNING MCS WAS OVER SE INYO COUNTY TRACKING TOWARD THE NORTHWEST. ANOTHER VORT WAS EVIDENT OVER NORTHERN NYE COUNTY. THIS FEATURE WAS HELPING INITIATE CONVECTION ACROSS THIS AREA. NONE OF THE 12Z MODELS INITIALIZED THE DUAL VORT STRUCTURE ACROSS SOUTHERN NEVADA WELL. WILL HAVE TO FOLLOW THESE FEATURES VIA SATELLITE. OTHERWISE...OVERALL SYNOPTIC PATTERN CHANGES VERY LITTLE RIGHT THROUGH THE 3 TO 5 DAY PERIOD WITH THE FOUR CORNERS HIGH CONTINUING TO PUMP MONSOONAL MOISTURE INTO THE REGION. WILL BROADBRUSH WITH SCATTERED POPS AFTERNOON AND EVENING ACROSS NORTHERN PORTIONS OF THE CWA AND ACROSS MOST OF MOHAVE COUNTY. WILL STAY WITH ISOLATED POPS ACROSS SOUTHERN PORTIONS OF THE CWA. LAS 2222. MATUSIEWICZ
Nearby
Severe Thunderstorm Warnings in Arizona, 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.