Alert archive / California / Flash Flood Warnings in 2001
Flash Flood Warning 1, NWS Phoenix, AZ
NWS Phoenix, AZ issued this flash flood warning at Jul 7, 2001, 1:05 PM PDT for Riverside County, California. It was in force for 25 min. No storm report in the archive falls inside the area while it was in force.
The area
The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties.
The facts
- Issued
- Jul 7, 2001, 1:05 PM PDT (20:05 UTC)
- Expired
- Jul 7, 2001, 1:30 PM PDT
- In force
- 25 min
- Issued by
- NWS Phoenix, AZ
- Area
- Whole counties; the outline is the Mesonet’s reconstruction
County Riverside County, CA
The radar
The Yuma radar (KYUX), 159 km from the middle of the area, began a volume at 20:04 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.
The nearest sounding before it
Yuma Intl Airpor, AZ (KYUM), launched 12:00Z, 8.1 hours before the alert went out and 146 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
- 251 J/kg
- Mixed-layer CIN
- -190 J/kg
- Mixed-layer LCL
- 1872 m above ground
- 0-6 km bulk shear
- 7 kt
- 0-1 km storm-relative helicity
- 16 m²/s²
- 0-3 km storm-relative helicity
- 20 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 NZUS97 KPSR 072006 FFWPHX CAC065-072130- BULLETIN - EAS ACTIVATION REQUESTED FLASH FLOOD WARNING NATIONAL WEATHER SERVICE PHOENIX AZ 105 PM MST SAT JUL 7 2001 THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A * FLASH FLOOD WARNING FOR... EAST CENTRAL RIVERSIDE COUNTY IN SOUTHEAST CALIFORNIA * UNTIL 230 PM PDT * AT 100 PM PDT...WEATHER SERVICE DOPPLER RADAR INDICATED VERY HEAVY RAIN OVER DESERT CENTER...OR ABOUT 4 MILES NORTHEAST OF DESERT CENTER...NEARLY STATIONARY. AN OBSERVER EARLIER STATED THAT LOCAL ROADS WERE ALREADY IMPASSABLE DUE TO PREVIOUS RAIN...SO ADDITIONAL RAINFALL TODAY WILL KEEP THESE ROADS IMPASSABLE AND CAUSE OTHER WASHES TO RUN. ALSO AFFECTED BY THIS FLASH FLOOD WARNING WILL BE STATE ROUTE 177 NORTHEAST FROM DESERT CENTER. 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 11549 3365 11530 3387 11510 3399 11533
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 Jul 7, 9:40 AM PDT, 3 hours 25 minutes earlier.
Area forecast discussion, Jul 7, 9:40 AM PDT, 3 hours 25 minutes before
AZZ020>028-CAZ030>033-072245- SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PHOENIX AZ 940 AM MST SAT JUL 7 2001 .SYNOPSIS... UPPER LEVEL HIGH PRESSURE WILL REMAIN IN PLACE OVER THE KANSAS AND OKLAHOMA AREA THE NEXT FEW DAYS. THIS WILL ALLOW A SOMEWHAT DRIER AIRMASS TO INFILTRATE THE SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA ZONES THE NEXT TWO OR THREE DAYS. FURTHER EAST...SUFFICIENT MOISTURE WILL LIKELY REMAIN FOR MAINLY MOUNTAIN SHOWERS AND THUNDERSTORMS... MOSTLY IN THE AFTERNOON AND EVENING HOURS. LATER NEXT WEEK...THE UPPER HIGH WILL BEGIN TO MIGRATE WESTWARD. THIS SHIFT WILL ALLOW DEEPER MOISTURE TO BE BROUGHT BACK INTO THE DESERT SOUTHWEST. .DISCUSSION... AS IS ALWAYS THE CASE...MOISTURE AND INSTABILITY NOT THE GRAY AREAS TO FORECAST TODAY...HOWEVER...LIFTING MECHANISMS ARE. 12Z KPSR AND KYUM SOUNDINGS CONTAIN MORE THAN ENOUGH MOISTURE...WITH PWATERS OF NEAR 1.5 INCHES. ALSO...AMS VERY UNSTABLE...ESPECIALLY ON KYUM SOUNDING...WITH -10C H5 TEMP YIELDING A SFC BASED LI OF -6 AND CAPE OF NEARLY 1600 J/KG. THERE WAS ALSO A 60KT 250 MB JET OVER KYUM... DECREASING TO 25KTS AT KPSR...IMPLYING ANTICYCLONIC SHEAR...NOT FAVORABLE FOR UPPER LEVEL FORCING. HOWEVER...AS THIS JET LIFTS NWD...IT WILL PLACE SOME OF THE SW AZ DESERTS AND SE CA DESERTS...AT LEAST BRIEFLY...IN A FAVORABLE RIGHT-REAR QUADRANT POSITION. SO... THIS FACT...ALONG WITH THE SHORTWAVE EXPECTED TO MOVE THROUGH THE FAR WRN CWFA TODAY INTO THIS EVENING...WARRANTS A CONTINUED CHANCE OF SHOWERS/TSTMS. STEERING FLOWS WILL BE BASICALLY STRAIGHT SLY... SO IF WE CAN GET SOME NICE STORMS TO FIRE OVER THE NRN BAJA SPINE WE MAY SEE SOME CONVECTION APPROACH LOWER CO RIVER ZONES. WILL OPT TO UPDATE FOR THIS POSSIBILITY...AS WELL AS ZONES 26 AND 27 THIS AFTERNOON AND EVENING. STEERING FLOWS WEAKER OVER CENTRAL DESERT ZONES...SO WILL NOT HAVE ANYTHING IN 22 AND 23 FOR NOW. TOMORROW... WE START SEEING MORE OF A CONFLUENT FLOW ALOFT AND LOSE WHAT LITTLE DYNAMICS WE WILL HAVE TODAY. SO...WILL LEAVE CURRENT FORECASTS ALONE FOR SUNDAY. GOES WITHOUT SAYING...MAIN THREAT WITH STORMS WITH WEAK STEERING FLOWS WIsLL BE VERY HEAVY RAINFALL. ESTLE
In the hours before
Special weather statement, Jul 7, 10:30 AM PDT, 2 hours 35 minutes before
AZZ020>028-CAZ030>033-080700-
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE PHOENIX AZ
1030 AM MST SAT JUL 7 2001
...SCATTERED STRONG THUNDERSTORMS EXPECTED OVER PORTIONS OF SOUTH-
WEST ARIZONA AND FAR SOUTHEAST CALIFORNIA THROUGH TONIGHT...
COUNTIES IN THE RISK AREA INCLUDE...
IN ARIZONA...LAPAZ...YUMA
IN CALIFORNIA...IMPERIAL...EASTERN RIVERSIDE
THE PRIMARY HAZARDOUS WEATHER RISKS INCLUDE: VERY HEAVY RAINFALL.
ADDITIONAL THREATS INCLUDE: THUNDERSTORM-GENERATED WINDS GUSTING
AT TIMES TO NEAR 50 MPH...VISIBILITIES UNDER 1 MILE IN HEAVY
RAIN AND POSSIBLE BLOWING DUST.
ADDITIONAL INFORMATION: ISOLATED THUNDERSTORMS OVER SOUTH-CENTRAL
I ARIZONA COULD ALSO PRODUCE MUCH MORE LOCALIZED HEAVY RAINFALL
THIS AFTERNOON AND EVENING.
STORM SPOTTER ACTIVATION MAY BE NECESSARY LATER TODAY.
ESTLENearby
Flash Flood Warnings in California, 2001Every flash flood warning in 2001
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; radar from the NEXRAD Level II archive.