Alert archive / California / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 88, NWS Phoenix, AZ

September 5, 1997Imperial County, California

NWS Phoenix, AZ issued this severe thunderstorm warning at Sep 5, 1997, 4:04 PM PDT for Imperial County, California. It was in force for 61 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 5, 1997, 4:04 PM PDT (23:04 UTC)
Expired
Sep 5, 1997, 5:05 PM PDT
In force
61 min
Issued by
NWS Phoenix, AZ
Area
Whole counties

County Imperial County, CA

The radar

The Yuma radar (KYUX), 90 km from the middle of the area, began a volume at 23:03 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
Sep 5, 5:02 PM PDTThunderstorm Wind 50Seeley, CAPower poles were knocked down.

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

San Diego, CA (KNKX), launched 12:00Z, 11.1 hours before the alert went out and 173 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, San Diego, CA at 12:00Z on 1997-09-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 352 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, San Diego, CA at 12:00Z on 1997-09-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 29 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
352 J/kg
Mixed-layer CIN
-462 J/kg
Mixed-layer LCL
1263 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
29 m²/s²
0-3 km storm-relative helicity
64 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, Sep 5, 1:56 PM PDT, 2 hours 8 minutes before
AZZ020>025-CAZ030>033-061130-

SEVERE WEATHER OUTLOOK
NATIONAL WEATHER SERVICE PHOENIX AZ
145 PM MST/PDT FRI SEP 5 1997

...MODERATE RISK FOR SEVERE THUNDERSTORMS OVER CENTRAL AND EASTERN
RIVERSIDE...NORTHWEST IMPERIAL...NORTHERN YUMA AND WESTERN LA PAZ
COUNTIES THIS AFTERNOON AND EVENING...

...SLIGHT RISK FOR SEVERE THUNDERSTORMS OVER MARICOPA AND NORTHWEST
PINAL COUNTIES TONIGHT...

A STRONG UPPER LEVEL DISTURBANCE WILL MOVE EAST ACROSS SOUTH-CENTRAL
CALIFORNIA THIS AFTERNOON AND EVENING.  THE AIRMASS OVER FAR
SOUTHEAST CALIFORNIA IS VERY MOIST AND UNSTABLE. THUNDERSTORMS...
SOME SEVERE WITH DAMAGING WINDS...HAIL...AND VERY HEAVY RAIN
RESULTING IN LOCALIZED FLOODING...CAN BE EXPECTED OVER PORTIONS OF
CENTRAL AND EASTERN RIVERSIDE AND NORTHWEST IMPERIAL COUNTIES IN
CALIFORNIA...AS WELL AS OVER PORTIONS OF NORTHERN YUMA AND WESTERN
LA PAZ COUNTIES IN ARIZONA...THIS AFTERNOON AND TONIGHT.  THE JOSHUA
TREE NATIONAL PARK AND THE SALTON SEA STATE RECREATIONAL AREA ARE
INCLUDED IN THE MODERATE RISK AREA.  INDIVIDUAL STORMS WILL MOVE TO
THE NORTHEAST AT 20 MPH.

THE ATMOSPHERE IS ALSO QUITE UNSTABLE OVER SOUTH-CENTRAL ARIZONA.  A
WEAK UPPER LEVEL DISTURBANCE OVER NORTHERN MEXICO WILL MOVE WEST
TOWARD SOUTHEAST ARIZONA THIS AFTERNOON.  SCATTERED THUNDERSTORMS
WILL DEVELOP OVER EAST-CENTRAL AND SOUTHEAST ARIZONA THIS AFTERNOON
AND REDEVELOP TOWARD THE WEST AND NORTHWEST.  OUTFLOW FROM THESE
STORMS WILL GENERATE BLOWING DUST THAT MAY MOVE OVER PORTIONS OF
MARICOPA AND NORTHERN PINAL COUNTIES LATE THIS AFTERNOON OR EVENING.
SCATTERED THUNDERSTORMS...SOME SEVERE...MAY AFFECT PORTIONS
OF THE GREATER PHOENIX METRO...AS WELL AS CASA GRANDE AND GILA BEND
...TONIGHT.  DAMAGING STRAIGHT LINE WINDS AND BRIEF HEAVY RAIN ARE
POSSIBLE WITH THE STRONGEST STORMS.  INDIVIDUAL STORMS WILL MOVE TO
THE NORTHWEST AT 10 MPH.

THUNDERSTORMS WILL ALSO AFFECT SOME LOCATIONS IN SOUTHERN GILA
COUNTY THIS AFTERNOON AND EVENING.  BRIEF HEAVY RAIN AND GUSTY WINDS
CAN BE EXPECTED WITH THE STRONGER STORMS...BUT STORMS ARE EXPECTED
TO STAY BELOW SEVERE LIMITS.

....................................................................

FOR THE PURPOSES OF THIS OUTLOOK...SEVERE WEATHER REFERS TO ANY OF
THE FOLLOWING...DAMAGING WINDS IN EXCESS OF 57 MPH...HAIL 3/4 INCH
IN DIAMETER OR LARGER...AND LOCALLY HEAVY RAINFALL WHICH RESULTS IN
RUNNING WASHES OR FLOODING.

THE OUTLOOK AREA INCLUDES THE FOLLOWING COUNTIES...

IN ARIZONA                              IN CALIFORNIA

MARICOPA            YUMA                IMPERIAL
NORTHWEST PINAL     LA PAZ              CENTRAL AND EASTERN RIVERSIDE
SOUTHERN GILA
....................................................................

GREEN

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 5, 4:15 PM PDTSevere Thunderstorm WarningPSRLa Paz60 min

Nearby

Severe Thunderstorm Warnings in California, 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.