Alert archive / California / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 85, NWS Phoenix, AZ

September 9, 1998Imperial County, California

NWS Phoenix, AZ issued this severe thunderstorm warning at Sep 9, 1998, 3:52 PM PDT for Imperial County, California. It was in force for 38 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
Sep 9, 1998, 3:52 PM PDT (22:52 UTC)
Expired
Sep 9, 1998, 4:30 PM PDT
In force
38 min
Issued by
NWS Phoenix, AZ
Area
Whole counties

County Imperial County, CA

What was reported inside it

TimeReportWhereRemark
Sep 9, 4:13 PM PDTThunderstorm Wind 55Imperial, CAMeasured peak wind gust at the Imperial Airport.

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 nearest sounding before it

Yuma Intl Airpor, AZ (KYUM), launched 12:00Z, 10.9 hours before the alert went out and 84 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, Yuma Intl Airpor, AZ at 12:00Z on 1998-09-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 516 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, Yuma Intl Airpor, AZ at 12:00Z on 1998-09-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 49 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
516 J/kg
Mixed-layer CIN
-210 J/kg
Mixed-layer LCL
2063 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
49 m²/s²
0-3 km storm-relative helicity
46 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 KPHX 092253 RRA
SVRPHX
CAC025-092330-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
352 PM MST (352 PM PDT) WED SEP 9 1998

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

*  SEVERE THUNDERSTORM WARNING FOR
   WESTERN IMPERIAL COUNTY IN SOUTHEASTERN CALIFORNIA

*  UNTIL 430 PM PDT (430 PM MST)

*  AT 350 PM PDT DOPPLER RADAR INDICATED SEVERE THUNDERSTORMS
   OVER IMPERIAL AND NILAND.  MOVEMENT WAS TO THE NORTH NEAR 20 MPH.

*  SOME LOCATIONS AFFECTED INCLUDE
   NILAND
   CALIPATRIA
   BRAWLEY
   IMPERIAL

DAMAGING WINDS TO NEAR 65 MPH ARE LIKELY WITH THESE STORM. IN
ADDITION...HEAVY RAINFALL AND HAIL ARE LIKELY WITH THESE STORMS.

THIS IS AN EXTENSION AND AN EXPANSION OF THE WARNING ISSUED EARLIER.

The office that day

Everything else NWS Phoenix, AZ issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 9, 4:38 PM PDTSevere Thunderstorm WarningPSRImperial, Riverside52 min

Nearby

Severe Thunderstorm Warnings in California, 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.