Alert archive / Arizona / Severe Thunderstorm Warnings in 2003

Severe Thunderstorm Warning 82, NWS Phoenix, AZ

September 6, 2003La Paz County, Arizona

NWS Phoenix, AZ issued this severe thunderstorm warning at Sep 6, 2003, 5:50 PM MST for La Paz County, Arizona. It was in force for 55 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 6, 2003, 5:50 PM MST (00:50 UTC)
Expired: Sep 6, 2003, 6:45 PM MST
In force: 55 min
Issued by: NWS Phoenix, AZ
Area: Counties, with a storm outline in the text

County La Paz County, AZ

The radar

The Yuma radar (KYUX), 165 km from the middle of the area, began a volume at 00:51 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 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

Phoenix, AZ (KPSR), launched 00:00Z, 0.8 hours before the alert went out and 154 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: 629 J/kg
Mixed-layer CIN: -86 J/kg
Mixed-layer LCL: 1788 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 50 m²/s²
0-3 km storm-relative helicity: 68 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.9

Open this sounding in Storm Lab

The text

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

000 
WUUS55 KPSR 070050
SVRPSR
AZC012-070145-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
549 PM MST SAT SEP 6 2003

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EAST CENTRAL LA PAZ COUNTY IN WEST CENTRAL ARIZONA

* UNTIL 645 PM MST

* AT 541 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 13 MILES SOUTH OF SALOME...OR ABOUT 37 MILES   
  WEST OF TONOPAH...MOVING SOUTHEAST AT 20 MPH OVER INTERSTATE 10.

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...PUT YOUR CAR IN A GARAGE AND MOVE TO A 
SUBSTANTIAL SHELTER.

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH YOU SHOULD PREPARE
FOR DAMAGING WIND...LARGE HAIL...AND DEADLY LIGHTNING. PEOPLE OUTSIDE
SHOULD TAKE SHELTER...PREFERABLY IN A STRONG BUILDING AWAY FROM
WINDOWS.

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 3389 11373 3344 11384 3340 11336 3383 11335

$$

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 6, 3:55 PM MST, 1 hour 55 minutes earlier.

Area forecast discussion, Sep 6, 3:55 PM MST, 1 hour 55 minutes before

AZZ020>028-CAZ030>033-070545-

SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX ARIZONA
355 PM MST SAT SEP 6 2003

.SYNOPSIS...
A VERY MOIST AND UNSTABLE AIRMASS COUPLED WITH A WEATHER DISTURBANCE
MOVING EASTWARD ACROSS THE NORTHERN HALF OF ARIZONA WILL CONTINUE
THE THREAT OF STRONG THUNDERSTORMS OVER SOUTH CENTRAL ARIZONA
THROUGH THIS EVENING. THE AIRMASS SHOULD BECOME MORE STABLE BY
TONIGHT AS THE DISTURBANCE MOVES ON TO THE EAST AND DAYTIME HEATING
ENDS. A RIDGE OF HIGH PRESSURE ALOFT WILL MOVE OVER SOUTHEAST
CALIFORNIA AND ARIZONA SUNDAY. THERE WILL STILL BE SOME LOW AND MID
LEVEL MOISTURE OVER THE AREA SUNDAY...BUT THE AIRMASS WILL BE MORE
STABLE. HOWEVER...THERE WILL STILL BE A THREAT OF AFTERNOON
THUNDERSTORMS OVER THE MOUNTAINS IN ARIZONA...INCLUDING THE HIGHER
TERRAIN EAST OF PHOENIX. ANOTHER ROUND OF MOISTURE IS DUE TO ENTER
THE REGION STARTING MONDAY AND CONTINUING THROUGH TUESDAY AND
CONTINUING INTO CENTRAL ARIZONA POSSIBLY INTO WEDNESDAY. THIS WILL
BE DUE TO ANOTHER LOW PRESSURE DISTURBANCE ALONG WITH SOME MOISTURE
FROM THE REMAINS OF A TROPICAL STORM.

.DISCUSSION...
WHAT A DAY. SOUNDINGS THIS MORNING OVER SOUTHERN ARIZONA WERE VERY
MOIST AND UNSTABLE...AND WITH THE LOW PRESSURE TROUGH PASSING
THROUGH THE STATE...SOME SEVERE WEATHER DID OCCUR OVER THE REGION...
WITH EVEN REPORTS OF A TORNADO. ROTATION WAS ALSO NOTED ON THE
DOPPLER RADAR. ALSO...DUST STORMS ALONG WITH STREET AND SOME WASHES
FLOODING WERE REPORTED. THIS WAS ALL WITH A WEST TO NORTHWEST WIND
FLOW ALOFT...WHICH IS NORMALLY A DRY FLOW. SUBSIDENCE IS FORECAST TO
MOVE OVER THE REGION BY TONIGHT...AS THE TROUGH MOVES ON TO THE
EAST. HOWEVER...MID LEVEL MOISTURE REMAINS QUITE HIGH EVEN THROUGH
SUNDAY. BELIEVE...HOWEVER...THAT WITH A RIDGE OF HIGH PRESSURE
MOVING OVER THE REGION SUNDAY ALONG WITH A MORE STABLE AIRMASS
...THUNDERSTORMS SHOULD BE CONFINED MAINLY TO HIGHER TERRAIN. WILL
GO FOR MOSTLY SUNNY SKIES SUNDAY...THOUGH AFTERNOON CUMULUS SHOULD
STILL BE PRESENT WITH LOW AND MID LEVEL MOISTURE STILL AVAILABLE.

LOOKING AHEAD TO EARLY NEXT WEEK...ANOTHER LOW PRESSURE TROUGH WILL
BE MOVING OVER THE AREA MONDAY THROUGH TUESDAY NIGHT AND INTO
WEDNESDAY. MODELS PICK UP MOISTURE FROM WHAT APPEARS TO BE THE
REMAINS OF TROPICAL STORM KEVIN. THOUGH KEVIN IS FORECAST TO MOVE
FURTHER OUT TO THE WEST IN THE PACIFIC...THERE APPEARS TO BE A VORT
MAX FORECAST TO MOVE MONDAY NIGHT WITH ANOTHER DISTURBANCE ON
TUESDAY. AT THE SAME TIME...THERE SEEMS TO BE AN ABUNDANCE OF
MOISTURE COMING IN...SO THE THREAT OF THUNDERSTORMS WILL AGAIN
INCREASE. DRYING IS FORECAST FOR PARTICULARLY SOUTHEAST CALIFORNIA
DURING THE LATTER HALF OF NEXT WEEK. NOT SO SURE ABOUT CENTRAL
ARIZONA...BUT WILL KEEP MOSTLY CLEAR SKIES FROM THE PREVIOUS
FORECAST DUE TO LACK OF TIME TO UNCERTAINTY AT THIS TIME.

BERKOVITZ

.PSR...NONE.

Hazardous weather outlook, Sep 6, 11:35 AM MST, 6 hours 15 minutes before

AZZ020>028-CAZ030>033-070100-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE PHOENIX AZ
1135 AM MST SAT SEP 6 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.
HOWEVER...ISOLATED THUNDERSTORMS MAY DEVELOP MAINLY IN NORTH CENTRAL
AND NORTHEAST MARICOPA COUNTY AND OVER THE HIGHER TERRAIN THIS
AFTERNOON...WITH A FEW STRONG STORMS POSSIBLE OVER THE SALT RIVER
LAKES THIS AFTERNOON.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

In the hours before

Local storm report, Sep 6, 4:40 PM MST, 1 hour 10 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PHOENIX, AZ
440 PM MST SAT SEP 6 2003

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

0216 PM    PARADISE VALLEY           AZ   60 MPH TSTM WIND GUST
09/06/03   MARICOPA                       ESTIMATED 60 MPH WIND
                                          GUST. REPORTED BY TRAINED
                                          SPOTTER.

0230 PM    5 E MORRISTOWN            AZ   FLASH FLOODS
09/06/03   MARICOPA                       CAREFREE HIGHWAY AT MP 8
                                          CLOSED DUE TO FLASH
                                          FLOOD.REPORTED BY LAW
                                          ENFORCEMENT

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 7, 3:31 PM MST	Severe Thunderstorm Warning	PSR	Gila	59 min

Nearby

Severe Thunderstorm Warnings in Arizona, 2003 Every 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; radar from the NEXRAD Level II archive.