Alert archive / Arizona / Severe Thunderstorm Warnings in 2003

Severe Thunderstorm Warning 18, NWS Phoenix, AZ

July 28, 2003Maricopa County, Arizona

NWS Phoenix, AZ issued this severe thunderstorm warning at Jul 28, 2003, 2:14 PM MST for Maricopa County, Arizona. It was in force for 61 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
Jul 28, 2003, 2:14 PM MST (21:14 UTC)
Expired
Jul 28, 2003, 3:15 PM MST
In force
61 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), 54 km from the middle of the area, began a volume at 21:18 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 12:00Z, 9.2 hours before the alert went out and 67 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, Phoenix, AZ at 12:00Z on 2003-07-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 252 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, Phoenix, AZ at 12:00Z on 2003-07-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 65 square meters per square second.193958Sfc1 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
252 J/kg
Mixed-layer CIN
-263 J/kg
Mixed-layer LCL
1521 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
65 m²/s²
0-3 km storm-relative helicity
28 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
WUUS55 KPSR 282114
SVRPSR
AZC013-282215-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
212 PM MST MON JUL 28 2003

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHEASTERN MARICOPA COUNTY IN SOUTH CENTRAL ARIZONA

* UNTIL 315 PM MST

* AT 203 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 30 MILES SOUTHEAST OF SUNFLOWER...OR ABOUT 12
  MILES SOUTH OF ROOSEVELT...MOVING NORTHWEST AT 10 MPH.

* THE STORM WILL BE AFFECTING THE APACHE AND CANYON LAKE AREAS AS    
  WELL AS TORTILLA FLAT BY 220 PM.

THIS STORM WILL LIKELY PRODUCE WIND GUSTS IN EXCESS OF 60 MPH AND 
LARGE HAIL.

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 3347 11108 3349 11161 3380 11152 3393 11150
          3390 11143 3373 11134 3363 11123 3368 11116
          3351 11105

$$

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 Jul 28, 9:47 AM MST, 4 hours 27 minutes earlier.

Area forecast discussion, Jul 28, 9:47 AM MST, 4 hours 27 minutes before
AZZ020>028-CAZ030>033-282245-

SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
947 AM MST MON JUL 28 2003

.SYNOPSIS...
STRONG HIGH PRESSURE ALOFT WILL REMAIN OVER NEVADA THROUGH
WEDNESDAY. A WEAK LOW PRESSURE SYSTEM WILL MOVE ACROSS THE AREA
TODAY AND TONIGHT...AND WILL ENHANCE THE CHANCE OF SHOWERS AND
THUNDERSTORMS OVER SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA. HIGH
PRESSURE IS EXPECTED TO MOVE BACK TOWARDS THE FOUR CORNERS AREA MID
WEEK...FOR AN INCREASING CHANCE OF AFTERNOON AND EVENING
THUNDERSTORMS OVER SOUTH-CENTRAL ARIZONA...AND PARTLY CLOUDY SKIES
OVER SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

.DISCUSSION...
SAT IMAGERY THIS MORNING SHOWS MOSTLY CLOUDY SKIES ACROSS SOUTHEAST
CALIFORNIA...SOUTHWEST AND SOUTH-CENTRAL ARIZONA. INVERTED TROUGH
MOVING THROUGH ARIZONA AND CALIFORNIA TODAY WILL CONTINUE THE CHANCE
FOR SCATTERED SHOWERS AND THUNDERSTORMS. TWO AREAS OF ACTIVE WEATHER
THIS MORNING HAVE BEEN OUR MAIN CONCERN. ONE AREA OF WEATHER HAS
FINALLY MOVED SOUTHWEST FROM YUMA INTO MEXICO DURING THE PAST HOUR
OR SO. HOWEVER...THE OTHER AREA OF CONCERN AT THE MOMENT IS OVER
NORTHWEST MARICOPA COUNTY...NEAR THE TOWN OF WICKENBURG AND SOUTH
THEREOF. THIS AREA ALREADY RECEIVED ABOUT ONE AND A QUARTER INCHES
OF RAIN DURING THE LAST TWELVE HOURS...AND WE WILL KEEP AN EYE ON
THIS AREA THROUGHOUT THE DAY. SHOWERS WILL CONTINUE TO DRIFT
SOUTHWESTWARD (UNDER THE INFLUENCE OF A NORTHEAST/EASTERLY FLOW
ALOFT) THIS MORNING...AND WILL BE FOLLOWED BY A BREAK IN ACTIVITY
DURING THE LATE MORNING HOURS AND VERY EARLY AFTERNOON. HOWEVER...
MODELS ARE INDICATING A STRONG VORT MAX TO ROTATE THROUGH SOUTHWEST
ARIZONA DURING THE 18-00Z TIME FRAME...THEN THROUGH SOUTHEAST
CALIFORNIA FROM 00-06Z THIS EVENING. TO SUPPORT THE INSTABILITY OVER
THE AREA...12Z PSR AND NYL RAOBS THIS MORNING BOTH SHOW A RATHER
SIGNIFICANT AMOUNT OF COOLING AND MOISTENING THROUGH THE LOW TO MID
LEVELS. THIS AFTERNOON/EVENING COULD BE RATHER ACTIVE FOR PORTIONS
OF SOUTHEAST CALIFORNIA...SOUTHWEST AND SOUTH-CENTRAL ARIZONA...
DEPENDING ON HOW WELL THE BOUNDARY LAYER CAN RECOVER TODAY FROM THIS
MORNINGS ACTIVITY.

AS FOR THE SYNOPTIC PATTERN OVER THE AREA...THE MID TROPOSPHERIC
HIGH IS CURRENTLY CENTERED OVER NEVADA/UTAH WHERE IT WILL REMAIN
TODAY BEFORE MIGRATING BACK TOWARDS THE FOUR CORNERS REGION MID
WEEK. LOOKS LIKE THE WEATHER WILL REMAIN RATHER ACTIVE FOR ANOTHER
DAY OR SO...THEN BACK TO A LOW GRADE MONSOON WED/THU...AS THE
EASTERLY WAVES LESSEN IN NUMBER AND INTENSITY...AND THE FLOW ALOFT
SHIFTS FROM NORTHEAST/EAST TO A MORE SOUTHEAST FLOW (MORE TO COME IN
THIS AFTERNOONS DISCUSSION). FOR NOW...FORECAST LOOKS TO BE IN GOOD
SHAPE WITH NO UPDATES NEEDED. LW

.PSR...NONE.
Hazardous weather outlook, Jul 28, 6:00 AM MST, 8 hours 14 minutes before
AZZ020>028-CAZ030>033-290100-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE PHOENIX AZ
600 AM MST MON JUL 28 2003

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

.DAY ONE...TODAY

SHOWERS AND THUNDERSTORMS WILL OCCUR OVER SOUTHWEST ARIZONA AND INTO
SOUTHEAST CALIFORNIA THIS MORNING. THUNDERSTORMS WILL REDEVELOP OVER
SOUTH CENTRAL AND SOUTHWEST ARIZONA AS WELL AS SOUTHEAST CALIFORNIA
THIS AFTERNOON AND THIS EVENING. SOME OF THE MORNING STORMS MAY
PRODUCE LOCALLY HEAVY RAINS. SOME OF THE STORMS THIS AFTERNOON AND
THIS EVENING WILL AGAIN PRODUCE LOCALLY HEAVY RAINS ALONG WITH
STRONG GUSTY WINDS WITH THE POSSIBILITY OF BLOWING DUST CAUSING
REDUCED VISIBILITIES.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 27, 5:20 PM MSTSevere Thunderstorm WarningPSRMaricopa55 min

Nearby

Severe Thunderstorm Warnings in Arizona, 2003Every 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.