Flash Flood in Arizona, August 14, 2003

Name: Flash Flood in Arizona, August 14, 2003
Start: 2003-08-14T18:10
End: 2003-08-14T18:50
Location: Arizona

August 14, 2003 · NWS TWC · 1 event in 1 county or zone

Strong thunderstorms over Western Pima county produced heavy rain that flooded portions of Highway 85. A spotter from Organ Pipe National Monument reported flooding along Highway 85 between Why and Organ Pipe National Monument.

Where it happened

Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 1

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS TWC wrote it up.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Tucson, AZ wrote its last area forecast discussion before the first event at Aug 14, 2:30 PM MST, 3 hours 40 minutes earlier.

Area forecast discussion, Aug 14, 2:30 PM MST, 3 hours 40 minutes before

SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
230 PM MST THU AUG 14 2003

.SYNOPSIS...A STRONG LOW PRESSURE SYSTEM WILL MOVE FROM TEXAS INTO
ARIZONA OVER THE NEXT COUPLE OF DAYS...BRINGING AN INCREASE IN
THUNDERSTORMS ACROSS THE AREA. EXPECT COOLER AFTERNOONS TO GO ALONG
WITH THE INCREASE IN CLOUD COVER AND THUNDERSTORMS.

.DISCUSSION...EVERYTHING KIND OF SET UP SIMILAR TO WHAT MM5 SHOWED
THIS MORNING EXCEPT FOR OUTFLOW BOUNDARY THAT PUSHED INTO TUCSON
AREA. STORMS IN WHITE MOUNTAINS MOVING SOUTHWEST 15 OR 20 KNOTS AND
WILL INTERACT WITH MOIST BOUNDARY LAYER AWAITING IN LOW DESERTS TO
FIRE OFF LARGE AREA OF STORMS OVER THE LOW DESERTS TONIGHT. LEADING
THUNDERSTORMS HAVE DEVELOPED OVER SOUTHEAST PINAL COUNTY AHEAD OF
STORMS IN WHITE MOUNTAINS SHOWING SUPERCELL CHARACTERISTICS WITH
OTHER THUNDERSTORMS IN CENTRAL PIMA COUNTY. FLASH FLOOD AND SEVERE
WATCHES SHOULD EASILY VERIFY TODAY. REASON IS THAT WE ARE IN LEFT
FRONT QUADRANT OF THIS LOW WITH ALL THE ASSOCIATED DYNAMICS. HEAVY
RAIN THAT FELL IN PARTS OF PIMA AND PINAL COUNTIES LAST NIGHT MAKE
ANTECEDENT CONDITIONS FOR FLASH FLOODING PRIME...ESPECIALLY GIVEN
THAT WE SAW FLASHY SIGNATURES ON THE GAUGES DURING LAST NIGHTS
STORMS.

COLD POOL MOVES INTO AREA TOMORROW AND STORMS SHOULD HAVE NO
PROBLEMS DEVELOPING WITH SURFACE HEATING. THEY WILL NOT BE AS WELL
ORGANIZED...BUT WITH PLENTY OF MOISTURE WILL STILL HAVE SIMILAR
PROBLEMS ALTHOUGH MORE LIKE PULSE STORMS THAN SUPERCELLS.

NO RADICAL CHANGE SEEN THROUGH THE WEEKEND...ALTHOUGH WOULD EXPECT
LOWER CHANCES OF RAIN ESPECIALLY IF THIS LOW TAPS SOME DRY MID LEVEL
AIR. BUT MOISTURE WILL BE REINFORCED NEXT WEEK BY TROPICAL SYSTEM IN
GULF OF MEXICO.

.TWC...SEVERE THUNDERSTORM WATCH UNTIL 900 PM AZZ029-031>034
       FLASH FLOOD WATCH UNTIL MIDNIGHT AZZ029-031>034.

Hazardous weather outlook, Aug 14, 11:59 AM MST, 6 hours 11 minutes before

AZZ019-029>035-151400-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
12 NOON MST THU AUG 14 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST ARIZONA

.DAY ONE...TODAY

...FLASH FLOOD WATCH IN EFFECT FROM 2 PM MST THIS AFTERNOON UNTIL 12
MIDNIGHT TONIGHT FOR SOUTHEAST PINAL COUNTY...ALL OF PIMA COUNTY AND
SANTA CRUZ COUNTY...

SYNOPSIS...THUNDERSTORMS SHOULD FORM ON THE RIM TODAY AND MOVE
SOUTHWEST ACROSS THE AREA THIS EVENING. THE POTENTIAL FOR SEVERE
THUNDERSTORMS AND PRECIPITATION IN EXCESS OF ONE INCH IT IS ABOVE
CLIMATOLOGY...ESPECIALLY FROM TUCSON WEST.

DISCUSSION...A FEW LIGHT SHOWERS WERE PRESENT SOUTHEAST OF TUCSON
THIS MORNING AS DEBRIS CLOUD COVER FROM WEDNESDAY NIGHT CONVECTION
CONTINUES TO MOVE SOUTHWEST. THE UPPER LOW THAT WAS IN TEXAS OVER
THE PAST TWO DAYS HAS MIGRATED WEST AND IS SITUATED THIS AFTERNOON
IN CHIHUAHUA MEXICO. MODERATE NORTHEAST FLOW AHEAD OF THIS SYSTEM
WILL MOVE STORMS THAT DEVELOP ON THE RIM COUNTRY DOWN INTO THE LOWER
VALLEYS THIS AFTERNOON AND EVENING AND INTO THE LOW DESERTS WEST OF
TUCSON TONIGHT. THE THREAT OF SEVERE WEATHER (I.E. DAMAGING WINDS
AND HAIL) WILL BE HIGHER THAN NORMAL FROM TUCSON WEST BUT NEAR
CLIMATOLOGY IN THE EAST...WHERE SOME DRIER AIR HAS MOVED IN. A VERY
MOIST ATMOSPHERE IS IN PLACE FROM TUCSON WEST...WHERE PRECIPITABLE
WATER VALUES RANGE FROM 1.50 INCHES TO TWO INCHES. THIS AREA WILL
SEE THE BEST CHANCE OF HEAVY RAIN. THUS THE CHANCE OF ONE INCH
PRECIPITATION IS RATHER HIGH FROM TUCSON WEST...WHERE A FLASH FLOOD
WATCH IS IN EFFECT UNTIL 12 MIDNIGHT...BUT NEAR CLIMATOLOGY EAST OF
TUCSON. MOVEMENT OF THE STORMS WILL BE GENERALLY WEST TO SOUTHWEST
AROUND 10 TO 15 MPH.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

THE UPPER LOW IN CHIHUAHUA MEXICO WILL MOVE INTO THE STATE FRIDAY
AND WILL CONTINUE TO HELP FOCUS THUNDERSTORM DEVELOPMENT FRIDAY AND
FRIDAY NIGHT. THE UPSWING IN THUNDERSTORM COVERAGE WILL CONTINUE AND
THE CHANCE FOR HEAVY RAIN WILL REMAIN AT A LEVEL HIGHER THAN NORMAL.

.SPOTTER INFORMATION STATEMENT...

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

In the hours before

Special weather statement, Aug 14, 1:53 PM MST, 4 hours 17 minutes before

AZZ029-031>034-150400-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TUCSON AZ
153 PM MST THU AUG 14 2003

THE STORM PREDICTION CENTER HAS ISSUED SEVERE THUNDERSTORM WATCH
NUMBER 859 FOR SOUTH CENTRAL ARIZONA EFFECTIVE UNTIL 900 PM MST.
THIS WATCH INCLUDES SOUTHEAST PINAL...SANTA CRUZ AND PIMA COUNTIES.

THIS WATCH INCLUDES THE ENTIRE TUCSON METRO AREA...AJO...SELLS...
ELOY...ORACLE...AND NOGALES.

CONDITIONS HAVE BECOME FAVORABLE FOR LARGE HAIL UP TO 2 INCHES IN
DIAMETER...WIND GUSTS UP TO 80 MPH...AND TORRENTIAL RAINS IN THIS
AREA. A FLASH FLOOD WATCH IS ALSO IN EFFECT FOR THIS SAME AREA UNTIL
MIDNIGHT TONIGHT. BE PREPARED TO TAKE QUICK ACTION IF A WARNING IS
ISSUED.

PYTLAK

Local storm report, Aug 14, 4:45 PM MST, 1 hour 25 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TUCSON AZ
0445 PM MST THU AUG 14 2003

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

0355 PM    ORACLE                    AZ   WIND DAMAGE
08/14/03   PINAL                          STURDY TEEPEE SUPPORTED BY
                                          10 SIX INCH DIAMETER POLES
                                          BLOWN DOWN.

MG

The radar

The Tucson radar (KEMX), 112 km away, was scanning. The volume nearest the first event began at 01:07 UTC.

Open the radar archive at this moment

Event by event

1 flash flood. Local standard time, as filed.

Flash Flood, Pima

When: August 14, 6:10 PM MST to 6:50 PM MST
Where: Pima County, Why
Reported by: TRAINED SPOTTER
Coordinates: 32.097, -111.790 (the zone’s center; the record gives no point)

What these are

Flash Flood: Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Arizona in 2003 Every state in 2003 This day in weather history Warnings in Arizona, August 2003

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 5377500.