Alert archive / Arizona / Flash Flood Warnings in 2003

Flash Flood Warning 5, NWS Phoenix, AZ

August 14, 2003Maricopa County, Arizona

NWS Phoenix, AZ issued this flash flood warning at Aug 14, 2003, 8:23 PM MST for Maricopa County, Arizona. It was in force for 37 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 14, 2003, 8:23 PM MST (03:23 UTC)
Expired: Aug 14, 2003, 9:00 PM MST
In force: 37 min
Issued by: NWS Phoenix, AZ
Area: Counties, with a storm outline in the text

County Maricopa County, AZ

The radar

The Phoenix radar (KIWA), 57 km from the middle of the area, began a volume at 03:27 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.

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

Phoenix, AZ (KPSR), launched 00:00Z, 3.4 hours before the alert went out and 44 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 485 J/kg
Mixed-layer CIN: -55 J/kg
Mixed-layer LCL: 2530 m above ground
0-6 km bulk shear: 19 kt
0-1 km storm-relative helicity: -18 m²/s²
0-3 km storm-relative helicity: -7 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 150325
FFWPSR
AZC013-150500-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
823 PM MST THU AUG 14 2003

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTH-CENTRAL MARICOPA COUNTY IN SOUTH CENTRAL                     
  ARIZONA...MAINLY THE CAREFREE AND NORTH SCOTTSDALE AREAS

* UNTIL 1000 PM MST

* BETWEEN 715 AND 815 PM...THUNDERSTORMS WITH VERY HEAVY RAIN        
  OCCURRED OVER THE AREA EXTENDING FROM CAVE CREEK AND CAREFREE EAST 
  TO ABOUT 10 MILES WEST OF SUNFLOWER. BETWEEN 730 AND 8 PM...1.5   
  OF RAIN FELL AT STAGECOACH WASH...WITH 1.9 TOTAL BETWEEN 715 AND  
  815 PM. RADAR INDICATES 2 TO 3 INCHES OF RAIN FELL OVER SOUTHEAST  
  CAREFREE BETWEEN 715 AND 815 PM. WASHES IN THE AREA WILL BE OUT OF 
  THEIR BANKS...AND SIGNIFICANT STREET FLOODING IS LIKELY. 

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE 
DANGERS OF FLOODS AND FLASH FLOODS. 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 3372 11195 3372 11153 3389 11155 3390 11195

$$

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 14, 3:20 PM MST, 5 hours 3 minutes earlier.

Area forecast discussion, Aug 14, 3:20 PM MST, 5 hours 3 minutes before

AZZ020>028-CAZ030>033-150545-

SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
320 PM MST THU AUG 14 2003

.SYNOPSIS...
VERY UNSETTLED WEATHER WILL BE THE RULE ACROSS SOUTHWEST ARIZONA AND
SOUTHEAST CALIFORNIA INTO THE WEEKEND AS AN UPPER LOW DRIFTS OVER
THE REGION FROM THE EAST. STRONG THUNDERSTORMS WILL RUMBLE ACROSS
SOUTH-CENTRAL ARIZONA THIS EVENING...WITH THE POTENTIAL FOR SEVERE
WEATHER. AFTER TONIGHT...A CHANCE OF SHOWERS AND THUNDERSTORMS WILL
CONTINUE...WITH ACTIVITY EXPECTED TO DECREASE SOMEWHAT OVER THE
UPCOMING WEEKEND. TEMPERATURES WILL BE WELL BELOW NORMAL ACROSS
SOUTH-CENTRAL ARIZONA ON FRIDAY DUE TO THE RAIN-COOLED AIR...WITH
READINGS EXPECTED TO REBOUND OVER THE WEEKEND. THE WEATHER WILL
RETURN TO A MORE NORMAL MONSOON PATTERN THE FIRST PART OF NEXT WEEK.

.DISCUSSION...
LOTS OF PARAMETERS COMING TOGETHER FOR A VERY ACTIVE EVENING ACROSS
MAINLY ERN CWFA. THESE FACTORS INCLUDE A VERY MOIST...UNSTABLE
AIRMASS...A FAVORABLE NELY STEERING FLOW WITH LOTS OF SHEER IN THE
0-6KM LAYER...DIVERGENCE ALOFT WITH LARGE SCALE MID LEVEL CONVERGENCE
...DYNAMICS WITH APPROACHING INVERTED TROF...IE JUST ABOUT ALL ONE
COULD ASK FOR TO ENSURE LOTS OF WEATHER. AS A RESULT...HAVE GONE
WITH VERY HIGH POPS FOR SCNTRL AZ TONIGHT INTO FRIDAY MORNING WITH
LOWER NUMBERS FURTHER W. SPC ISSUED A SEVERE THUNDERSTORM WATCH
EARLIER THIS AFTERNOON FOR BASICALLY SOUTH-CENTRAL INTO NE AZ TIL
04Z. IN ADDITION...HEAVY RAIN THREAT HAS PROMPTED US TO ISSUE FLASH
FLOOD WATCH FOR SCTNRL AZ UNTIL 12Z FRIDAY.

AFTER TONIGHT...INVERTED TROF MOVES INTO AZ AND THEN MEANDERS NWD
DURING THE WEEKEND. COOLER AIR ALOFT WILL SERVE TO DESTABLIZE THE
AMS EVEN FURTHER FRIDAY AND SATURDAY...ALTHOUGH IF TONIGHT IS ACTIVE
...WE WOULD HAVE LOTS OF CONVECTIVE INHIBITION TO OVERCOME IN THE
ABSENCE OF MORE UPPER FORCING. WE MAY HAVE SOME OF THAT BOTH FRIDAY
AND SATURDAY AS ADDITIONAL VORT MAXIMA ROTATE AROUND TROUGH. SO...
WILL BASICALLY KEEP CHANCE TYPE POPS GOING INTO SATURDAY...LOWERING
POPS A BIT ON SUNDAY...WITH A LOW GRADE MONSOON FORECAST MAINTAINED
MONDAY THRU THURSDAY.

.PSR...SVR TSTM WATCH SCNTRL AZ...ZONES 22...23...24...27 AND
       28 TIL 04Z.
       FLASH FLOOD WATCH SAME ZONES 00Z-12Z.

Hazardous weather outlook, Aug 14, 6:19 AM MST, 14 hours 4 minutes before

AZZ020>028-CAZ030>033-150100-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE PHOENIX AZ
619 AM MST THU AUG 14 2003

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

.DAY ONE...TODAY

THERE IS A CHANCE OF SHOWERS AND THUNDERSTORMS IN SOUTHWEST AND
SOUTH CENTRAL ARIZONA. THE STRONGEST STORMS WILL OCCUR LATE THIS
AFTERNOON AND EVENING. THUNDERSTORMS ARE CAPABLE OF PRODUCING STRONG
POSSIBLY DAMAGING WINDS...DENSE BLOWING DUST...AND LOCALLY HEAVY
RAIN.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

AN UNUSUALLY STRONG LOW PRESSURE SYSTEM MOVING FROM TEXAS INTO
ARIZONA WILL CONTINUE THE UNSETTLED WEATHER ON FRIDAY. A CHANCE FOR
SHOWERS AND THUNDERSTORMS CAN BE EXPECTED ACROSS PARTS OF SOUTHEAST
CALIFORNIA...AND SOUTHWEST AND SOUTH CENTRAL ARIZONA.  THUNDERSTORMS
ARE CAPABLE OF PRODUCING STRONG POSSIBLY DAMAGING WINDS...DENSE
BLOWING DUST...AND HEAVY RAINFALL.

DECREASING THREATS FOR SHOWERS AND THUNDERSTORMS ARE EXPECTED
THIS WEEKEND AND EARLY NEXT WEEK.

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

In the hours before

Local storm report, Aug 14, 6:07 PM MST, 2 hours 16 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PHOENIX, AZ
607 PM MST THU AUG 14 2003

TIME(MST)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0530 PM    5 E SACATON               AZ   FLASH FLOODS
08/14/03   PINAL                          FLOODING REPORTED ON STATE
                                          HIGHWAY 87 NEAR MILE MARKER
                                          147. ROAD REPORTED AS
                                          IMPASSIBLE. REPORTED BY LAW
                                          ENFORCEMENT

FOWLE

Local storm report, Aug 14, 6:37 PM MST, 1 hour 46 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PHOENIX, AZ
637 PM MST THU AUG 14 2003

TIME(MST)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0615 PM    QUEEN CREEK               AZ   60 MPH TSTM WIND GUST
08/14/03   MARICOPA                       ESTIMATED WIND GUST
                                          MEASURED BY STORM SPOTTER.

FOWLE

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 14, 5:10 PM MST	Flash Flood Warning	PSR	Pinal	50 min
Aug 14, 5:17 PM MST	Severe Thunderstorm Warning	PSR	Pinal	58 min
Aug 14, 6:06 PM MST	Severe Thunderstorm Warning	PSR	Gila	54 min
Aug 14, 6:07 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	53 min
Aug 14, 6:35 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	55 min
Aug 14, 7:29 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	61 min
Aug 14, 7:33 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	57 min
Aug 14, 8:28 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	62 min

Nearby

Flash Flood Warnings in Arizona, 2003 Every 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; radar from the NEXRAD Level II archive.