Alert archive / California / Flash Flood Warnings in 2003

Flash Flood Warning 10, NWS Phoenix, AZ

August 26, 2003Riverside County, San Bernardino County, California

NWS Phoenix, AZ issued this flash flood warning at Aug 26, 2003, 3:03 PM PDT for Riverside County, San Bernardino County, California. It was in force for 117 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
Aug 26, 2003, 3:03 PM PDT (22:03 UTC)
Expired
Aug 26, 2003, 5:00 PM PDT
In force
117 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 flash flood 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

Yuma Intl Airpor, AZ (KYUM), launched 12:00Z, 10.1 hours before the alert went out and 175 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 2003-08-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 111 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, Yuma Intl Airpor, AZ at 12:00Z on 2003-08-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -18 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
111 J/kg
Mixed-layer CIN
-261 J/kg
Mixed-layer LCL
2175 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
-18 m²/s²
0-3 km storm-relative helicity
22 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WGUS55 KPSR 262208
FFWPSR
CAC065-071-270000-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
303 PM PDT TUE AUG 26 2003

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  JOSHUA TREE NATIONAL PARK INCLUDING PARTS OF   
  NORTH CENTRAL RIVERSIDE COUNTY IN SOUTHEAST CALIFORNIA
  EXTREME SOUTH CENTRAL SAN BERNARDINO COUNTY IN SOUTHEAST         
  CALIFORNIA

* UNTIL 500 PM PDT

* AT 256 PM PDT...WEATHER SERVICE DOPPLER RADAR INDICATED VERY HEAVY
  RAIN 13 MILES NORTH OF COTTONWOOD VISITOR CENTER...OR ABOUT 20
  MILES SOUTHEAST OF TWENTYNINE PALMS.  THE AREA OF HEAVY RAIN WAS
  NEARLY STATIONARY.

FLASH FLOODING WILL OCCUR ALONG PINTO BASIN ROAD...BLACK EAGLE MINE 
ROAD...OLD DALE ROAD...AND IN PINTO WASH.  


EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF CREEKS
AND STREAMS...ROADS AND ROADSIDE CULVERTS. THE HEAVY RAINS COULD ALSO
TRIGGER ROCK AND MUDSLIDES IN STEEP TERRAIN.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. VEHICLES CAUGHT IN RISING WATER SHOULD BE ABANDONED QUICKLY.
MOVE TO HIGHER GROUND.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY
AUTOMOBILE. IF YOUR VEHICLE STALLS...ABANDON IT IMMEDIATELY AND SEEK
HIGHER GROUND.

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

LAT...LON 3375 11601 3373 11577 3376 11562 3389 11558
          3412 11525 3412 11627

$$

What forecasters said that day

The local office's own words before this flash flood 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 flash flood warning went out at Aug 26, 10:30 AM PDT, 4 hours 33 minutes earlier.

Area forecast discussion, Aug 26, 10:30 AM PDT, 4 hours 33 minutes before
AZZ020>028-CAZ030>033-262245-

SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION
WEATHER SERVICE PHOENIX AZ
1030 AM MST TUE AUG 26 2003

.SYNOPSIS...
A FLOW ALOFT FROM THE EAST THEN SOUTH IS EXPECTED TODAY THROUGH
WEDNESDAY AS HIGH PRESSURE ALOFT REMAINS CENTERED NORTH AND EAST OF
ARIZONA. IN ADDITION...THERE WILL BE AN INCREASE IN MOISTURE THROUGH
WEDNESDAY FROM HURRICANE IGNACIO...WHICH WILL MOVE SLOWLY NORTHWEST
UP THE BAJA COAST THROUGH WEDNESDAY NIGHT. THIS MEANS AN INCREASING
CHANCE OF SHOWERS AND THUNDERSTORMS...SOME HEAVY RAIN...AND COOLER
WEATHER. HIGH PRESSURE ALOFT FROM THE PACIFIC IS EXPECTED TO BRING A
REDUCTION IN THUNDERSTORMS BY FRIDAY.

.DISCUSSION...
A FLASH FLOOD WATCH WAS ISSUED FOR SOUTHWEST ARIZONA AND SOUTHEAST
CALIFORNIA THIS MORNING AND IS IN EFFECT UNTIL 10 PM MST AND PDT OR
0500 GMT THIS EVENING. A FLASH FLOOD WATCH IS PLANNED FOR
SOUTH-CENTRAL ARIZONA INCLUDING THE GREATER PHOENIX AREA TO BEGIN BY
MID OR LATE THIS AFTERNOON AND CONTINUE THROUGH WEDNESDAY. MOISTURE
SPINNING OFF OF FORMER HURRICANE...NOW TROPICAL STORM IGNACIO IS
MOVING TOWARD US AND THERE WAS EVEN A STRONG GULF SURGE BELOW 5
THOUSAND FEET INTO YUMA THIS MORNING WITH WIND GUSTING TO 35 MPH AND
VISIBILITY DOWN TO 4 MILES IN BLOWING DUST AROUND 5 AND 6 AM MST.
HURRICANE IGNACIO WAS MOVING NORTHWEST OVER SOUTHERN AND CENTRAL
BAJA CALIFORNIA THIS MORNING. WITH MOISTURE ALREADY HERE...AND
MOISTURE FROM THE SOUTHEAST ON THE EAST SIDE OF IGNACIO MOVING THIS
WAY...EXPECT AN INCREASING CHANCE OF SHOWERS AND THUNDERSTORMS...
SOME HEAVY RAIN...AND COOLER WEATHER THROUGH WEDNESDAY. THE MAIN
MOISTURE INCREASE IS EXPECTED TO CONTINUE TODAY THROUGH WEDNESDAY
LEADING TO AN INCREASING PROBABILITY OF SHOWERS AND THUNDERSTORMS
WITH SOME HEAVY RAIN AND AN INCREASED FLASH FLOOD POTENTIAL. THUS...
THE REASON FOR THE FLASH FLOOD WATCHES. HIGH PRESSURE ALOFT FROM THE
PACIFIC IS EXPECTED TO BRING A REDUCTION IN THUNDERSTORMS BY FRIDAY.
THEN...THE WEAK LOW PRESSURE SYSTEM ASSOCIATED WITH IGNACIO IS
EXPECTED TO MOVE NORTH BRINGING SOME INCREASE IN THE CHANCE AND
SHOWERS AND THUNDERSTORMS THIS COMING LABOR DAY WEEKEND.

.PSR...FLASH FLOOD WATCH FOR SOUTHWEST ARIZONA AND SOUTHEAST
       CALIFORNIA ZONES 20...21...25...26...30...31...32...AND 33
       YUMA COUNTY...LA PAZ COUNTY...IMPERIAL COUNTY AND EASTERN
       RIVERSIDE COUNTY INCLUDING ALL OF JOSHUA TREE NATIONAL PARK
       10 PM MST THIS EVENING OR 27/0500 GMT.

ELLIS
Hazardous weather outlook, Aug 26, 6:00 AM PDT, 9 hours 3 minutes before
AZZ020>028-CAZ030>033-270100-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE PHOENIX AZ
600 AM MST TUE AUG 26 2003

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

.DAY ONE...TODAY

THE AIRMASS OVER ARIZONA AND SOUTHEAST CALIFORNIA REMAINS VERY
MOIST AND UNSTABLE...AND ADDITIONAL MOISTURE IS EXPECTED TO MOVE
INTO ARIZONA FROM FORMER HURRICANE IGNACIO. THUS SCATTERED
THUNDERSTORMS ARE FORECAST TO DEVELOP TODAY...MAINLY IN THE LATE
AFTERNOON AND EVENING HOURS. HEAVY RAIN IS POSSIBLE WITH ANY
THUNDERSTORM...AS WELL AS SOME BLOWING DUST AND STRONG GUSTY WINDS.
HEAVY RAIN COULD LEAD TO FLOODING OF ROADS...WASHES AND OTHER LOW
SPOTS.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

THERE WILL BE AN INCREASED THREAT FOR SHOWERS AND THUNDERSTORMS WITH
HEAVY RAIN WEDNESDAY AND WEDNESDAY NIGHT...ESPECIALLY OVER
SOUTH-CENTRAL ARIZONA...AS MOISTURE FROM IGNACIO CONTINUES TO SPREAD
INTO ARIZONA. STAY AWAY FROM FLOODED AREAS INCLUDING ROADWAYS AND
WASHES...AND BE PREPARED TO MOVE TO HIGHER GROUND SHOULD A WARNING
BE ISSUED.

.INSTRUCTIONS TO SPOTTERS...
WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

BRECKENRIDGE

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 26, 4:06 PM PDTSevere Thunderstorm WarningPSRRiverside54 min

Nearby

Flash Flood Warnings in California, 2003Every flash flood 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.