Alert archive / California / Severe Thunderstorm Warnings in 2003

Severe Thunderstorm Warning 65, NWS Phoenix, AZ

September 2, 2003Riverside County, San Bernardino County, California

NWS Phoenix, AZ issued this severe thunderstorm warning at Sep 2, 2003, 2:27 PM PDT for Riverside County, San Bernardino County, California. It was in force for 63 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Sep 2, 2003, 2:27 PM PDT (21:27 UTC)
Expired
Sep 2, 2003, 3:30 PM PDT
In force
63 min
Issued by
NWS Phoenix, AZ
Area
Counties, with a storm outline in the text

Counties Riverside County, CA, San Bernardino County, CA

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

San Diego, CA (KNKX), launched 12:00Z, 9.5 hours before the alert went out and 162 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 2003-09-02Temperature 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 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 2003-09-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 10 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1284 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
10 m²/s²
0-3 km storm-relative helicity
104 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 
WUUS55 KPSR 022127
SVRPSR
CAC065-071-022230-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
225 PM PDT TUE SEP 2 2003

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTH CENTRAL RIVERSIDE COUNTY IN SOUTHEAST CALIFORNIA
  SOUTH CENTRAL SAN BERNARDINO COUNTY IN SOUTHEAST CALIFORNIA

* UNTIL 330 PM PDT
  
* THIS STORM WILL AFFECT BLACK ROCK CANYON...KEYS VIEW...HIDDEN      
  VALLEY CAMPGROUND...AND PINTO BASIN ROAD.   

* AT 225 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 10 MILES NORTHWEST OF LOST HORSE-KEYS VIEW
  JTNP...OR ABOUT 16 MILES NORTHEAST OF CATHEDRAL CITY...MOVING      
  NORTHWEST AT10 MPH.

DAMAGING MICROBURST WINDS ARE LIKELY WITH THIS STORM. VERY HEAVY RAIN
IS ALSO POSSIBLE. TAKE COVER IN A SUBSTANTIAL SHELTER UNTIL THE STORM
PASSES.

LARGE HAIL IS POSSIBLE WITH THIS SEVERE THUNDERSTORM. IF YOU ARE IN 
THE PATH OF THE STORM.

INTENSE LIGHTNING IS OCCURRING WITH THIS STORM...MOVE INDOORS IF 
POSSIBLE. WHEN INDOORS...STAY AWAY FROM WINDOWS AND DOORS. IF 
OUTDOORS...AVOID ISOLATED TALL OBJECTS SUCH AS TREES.

REPORT SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY. THEY
WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST
OFFICE IN PHOENIX.

LAT...LON 3403 11653 3373 11604 3385 11578 3433 11615

$$

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 Phoenix, AZ wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 2, 8:55 AM PDT, 5 hours 32 minutes earlier.

Area forecast discussion, Sep 2, 8:55 AM PDT, 5 hours 32 minutes before
AZZ020>028-CAZ030>033-022245-

SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
855 AM MST TUE SEP 2 2003

.SYNOPSIS...
HIGH PRESSURE ALOFT WILL REMAIN NEAR THE UTAH BORDER TODAY AND
WEDNESDAY BEFORE MOVING SOUTHWEST OVER SOUTHERN CALIFORNIA THURSDAY
...AND OFF THE NORTHERN BAJA CALIFORNIA COAST FRIDAY THROUGH EARLY
NEXT WEEK. THIS WILL BRING A DRIER FLOW OF AIR ALOFT FROM THE
PACIFIC WITH A REDUCTION IN THUNDERSTORMS OVER SOUTHEAST CALIFORNIA
AND SOUTHWEST ARIZONA BY THE END OF THE WEEK...AND OVER
SOUTH-CENTRAL ARIZONA BY SUNDAY. TEMPERATURES WILL BE COOLER BY
EARLY NEXT WEEK.

.DISCUSSION...
A HEAT ADVISORY HAS BEEN ISSUED FOR SOUTH-CENTRAL ARIZONA DESERT
ZONES 22...23...27...AND 28...MARICOPA COUNTY INCLUDING THE GREATER
PHOENIX AREA...AND NORTHWEST AND NORTH-CENTRAL PINAL COUNTY TODAY
AND WEDNESDAY.

SAT IMAGERY THIS MORNING SHOWS PARTLY CLOUDY SKIES OVER SE CA...SW
AND S-CNTRL AZ UNDER A SOUTHEAST FLOW ALOFT. LAST NIGHTS CONVECTION
IS WELL NORTH OF THE AREA...NEAR LAS VEGAS THIS MORNING...AND SKIS
SHOULD BEGIN TO CLEAR OVER OUR CWA AS THE DAY WEARS ON. KPSR
SOUNDING INDICATES PWATER IS DOWN FROM 1.76 INCHES YESTERDAY TO 1.48
INCHES TODAY...AND DRYING IS EVIDENT FROM THE SFC TO ABOUT 600 MB.
FURTHERMORE...24 HR CHANGE PRODUCT INDICATES DEW POINTS ARE DOWN 3
TO 10 DEG ACROSS MUCH OF THE AREA. SEEMS THE BEST SUPPORT ALOFT FOR
SHOWERS AND THUNDERSTORMS WILL BE OVER NRN AZ...WITH WEAK SUBSIDENCE
FCST FOR THE CNTRL AND SRN AZ. WILL LIKELY UPDATE FORECAST TO LOWER
POPS FROM 20 TO 10 OVER SW AND S-CNTRL AZ DESERTS...KEEPING SLIGHTLY
HIGHER POPS OVER SRN CA AS A BULLSEYE OF UPPER LEVEL DIVERGENCE
STRETCHES FROM SE CA TO NE AZ FROM 00-06Z. OTHER THAN SOME MINOR
TWEAKING TO THE POPS...NO FURTHER UPDATES ARE NEEDED AT THIS TIME.

BEYOND TODAY...HIGH PRESSURE ALOFT JUST SOUTH OF THE 4 CORNERS
REGION WILL EXTEND NW TO NV TONIGHT AND WED NIGHT. THE HIGH WILL
THEN MOVE SOUTHWEST OVER SRN CA THU...AND OFF THE NRN BAJA CA COAST
FRI THROUGH EARLY NEXT WEEK. THIS WILL BRING A DRIER FLOW OF AIR
ALOFT FROM THE PACIFIC WITH A REDUCTION IN THUNDERSTORMS OVER SE CA
AND SW AZ BY THE END OF THE WEEK...AND OVER S-CNTRL AZ INCLUDING THE
GREATER PHOENIX AREA BY SUN. FURTHERMORE...A LOW PRESSURE SYSTEM
MOVING TOWARD THE WRN US WILL RESULT IN COOLER TEMPS BY EARLY NEXT
WEEK.

.PSR...HEAT ADVISORY FOR SOUTH-CENTRAL ARIZONA DESERT ZONES 23...
       22...27...AND 28 MARICOPA COUNTY INCLUDING THE GREATER
       PHOENIX AREA...AND NORTHWEST AND NORTH-CENTRAL PINAL COUNTY
       TODAY AND WEDNESDAY.
Hazardous weather outlook, Sep 2, 6:00 AM PDT, 8 hours 27 minutes before
AZZ020>028-CAZ030>033-030100-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE PHOENIX AZ
600 AM MST TUE SEP 2 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHWEST AND
SOUTH-CENTRAL ARIZONA...AND SOUTHEAST CALIFORNIA.

.DAY ONE...TODAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

Nearby

Severe Thunderstorm Warnings in California, 2003Every severe thunderstorm warning in 2003

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.