Alert archive / Arizona / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 4, NWS Phoenix, AZ

July 9, 2002Maricopa County, Pinal County, Arizona

NWS Phoenix, AZ issued this severe thunderstorm warning at Jul 9, 2002, 5:41 PM MST for Maricopa County, Pinal County, Arizona. It was in force for 49 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Jul 9, 2002, 5:41 PM MST (00:41 UTC)
Expired: Jul 9, 2002, 6:30 PM MST
In force: 49 min
Issued by: NWS Phoenix, AZ
Area: Counties, with a storm outline in the text

Counties Maricopa County, AZ, Pinal County, AZ

The radar

The Phoenix radar (KIWA), 14 km from the middle of the area, began a volume at 00:42 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.

What was reported inside it

Time	Report	Where	Remark
Jul 9, 6:00 PM MST	Thunderstorm Wind 52 E	Mesa, AZ	Dense blowing dust accompanied winds that gusted to about 60 mph. A small airplane was damaged while trying to land at Falcon Field. Thunderstorms developed over the East Valley, and microburst winds struck in Mesa, along University Drive between Extension an

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jul 9, 4:30 PM MST	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Phoenix, AZ (KPSR), launched 00:00Z, 0.7 hours before the alert went out and 21 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: 443 J/kg
Mixed-layer CIN: -95 J/kg
Mixed-layer LCL: 3138 m above ground
0-6 km bulk shear: 19 kt
0-1 km storm-relative helicity: 2 m²/s²
0-3 km storm-relative helicity: 82 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 100044
SVRPSR
AZC013-021-100130-

BULLETIN - EAS ACTIVATION REQUESTED...CORRECTION
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
541 PM MST TUE JUL 9 2002

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EAST CENTRAL MARICOPA COUNTY IN SOUTH CENTRAL ARIZONA
  NORTH CENTRAL PINAL COUNTY IN SOUTH CENTRAL ARIZONA

* UNTIL 630 PM MST

* AT 532 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM OVER APACHE JUNCTION...OR ABOUT 4 MILES
  SOUTHEAST OF APACHE JUNCTION...MOVING WEST AT 20 MPH.

THESE STORMS WERE MOVING INTO APACHE JUNCTION...AND TOWARD GILBER...
EAST MESA...AND EAST CHANDLER.

DAMAGING MICROBURST WINDS ARE LIKELY WITH THIS STORM. TAKE COVER IN A
STURDY STRUCTURE UNTIL THE STORM PASSES.

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.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM MST
TUESDAY EVENING FOR SOUTHEASTERN ARIZONA.

LAT...LON 3351 11195 3323 11198 3321 11148 3350 11140

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 9, 3:20 PM MST, 2 hours 21 minutes earlier.

Area forecast discussion, Jul 9, 3:20 PM MST, 2 hours 21 minutes before

AZZ020>028-CAZ030>033-100545-

SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
320 PM MST TUE JUL 9 2002

.SYNOPSIS...
STRONG HIGH PRESSURE ALOFT OVER THE CENTRAL AND SOUTHERN ROCKIES IS
EXPECTED TO DEVELOP A DEEP EASTERLY FLOW ACROSS SOUTHWEST ARIZONA
AND SOUTHEAST CALIFORNIA THIS WEEK. THIS WILL IMPORT MOISTURE FROM
THE EAST...PROVIDING A GOOD START TO THE SUMMER THUNDERSTORM SEASON.
THIS INCREASE IN MOISTURE WILL LEAD TO SCATTERED THUNDERSTORMS OVER
SOUTH CENTRAL ARIZONA TONIGHT. IN ADDITION...A SERIES OF MINOR LOW
PRESSURE SYSTEMS WILL BE MOVING WESTWARD OVER NORTHERN MEXICO...
INCREASING THUNDERSTORM ACTIVITY THERE AND THUS FEEDING ADDITIONAL
MOISTURE INTO THIS AREA. LOOK FOR INCREASING CHANCES OF SHOWERS AND
THUNDERSTORMS...WITH SOME BLOWING DUST ON THE LOWER DESERTS...AS THE
WEEK PROGRESSES.

.DISCUSSION...
APPEARS THAT THE MONSOON IS ABOUT READY TO MAKE ITS OFFICIAL
APPEARANCE...AS LOW LEVEL MOISTURE VALUES ARE UP SUBSTANTIALLY TODAY
AND CONVECTION IS FIRING NICELY OVER ERN AZ...AND HEADED OUR WAY. A
VERY STRONG HIGH PRESSURE RIDGE CONTINUES OVER THE WESTERN STATES
WITH A 6000M HIGH CENTER NOW OVER SRN NV. THIS GIVING A RATHER
STRONG DEEP ELY FLOW TO MOST OF THE STATE...WITH MEAN WINDS IN THE
0-6KM LAYER FROM THE EAST AT 20KT. THIS ELY FLOW ADVECTING IN QUITE
A BIT OF MOISTURE...PWAT VALUES OVER SRN AZ NOW RUNNING OVER 1.5
INCHES OVER MUCH OF THE AREA...AS SEEN BOTH GOES PWAT IMAGERY AND
THE TUS/PHX RAOBS. AT 3 PM SURFACE DEWPOINTS OVER MOST OF THE SCNTRL
DESERTS WERE IN THE 50S. TEMPS AGAIN HAVE CLIMBED NICELY...AIDED IN
PART BY THE UNREASONABLY HOT LOW TEMPERATURES SEEN ACROSS THE
DESERTS THIS MORNING. SOME SPOTS REACHING TO AROUND 110 DEGREES
AGAIN. PHX...BTW...TIED THE ALL TIME RECORD HIGH MINIMUM OF 93
DEGREES THIS MORNING. IN ANY CASE...SCT STORMS ARE FIRING OVER THE
ERN MOUNTAINS AND ARE MOVING WEST...SHOULD MOVE INTO OUR ERN ZONES
TONIGHT. CONVECTION IS AIDED BY A STRONG INVERTED TROF THAT WILL
MOVE SWWD OUT OF NM AND INTO ECNTRL AZ OVERNIGHT...THEN ACROSS OUR
DESERTS WED. THIS DISTURBANCE WILL LIKLEY CAUSE CONVECTION TO
CONTINUE WELL PAST MIDNIGHT AND POSSIBLY INTO THE MORNING HOURS.
THUS WILL CONTINUE TO FORECAST A SLIGHT CHANCE FOR MORNING SHOWERS
OR STORMS OVER MOST OF THE AZ LOWER DESERTS. AS FOR WED AND
BEYOND...BASIC FLOW PATTERN NOT FORECAST TO CHANGE MUCH THRU
SAT...WITH THE STRONG UPPER HIGH REMAINING TO OUR NE...A MODERATE
ELY FLOW ACROSS THE CWA...GIVING A CHANCE FOR AFTN/EVE STORMS TO
DEVELOP AND MOVE OFF THE HIGHER TERRAIN AND OVER THE LOWER DESERTS
EACH DAY. ONCE THE MOISTURE GETS IN PLACE...BY WED...IT WILL NOT
REALLY LEAVE ANYTIME SOON SO THUS THE STANDARD MONSOON FORECAST WILL
HOLD THRU THE WEEKEND. LATEST MRF/AVN CONTINUE TO SUGGEST THAT THERE
WILL BE A GOOD SUBTROPICAL TAP DEVELOPING SUNDAY INTO MIDDLE OF NEXT
WEEK...WITH THE FLOW BECOMING MORE SELY AND ABLE TO TAP MOISTURE TO
OUR SOUTH ASSOCIATED WITH SOME SORT OF TROPICAL
DISTURBANCE/DEPRESSION. THUS THESE PROGS REALLY UP THE RH OVER OUR
WESTERN ZONES SUN THRU TUE...AND LOWER TEMPS SOMEWHAT IN RESPONSE.
WILL KEEP THE BROADBRUSHED FORECAST GOING FOR SAT THRU TUE...BUT
MENTION A TEMP FALLOFF OF A FEW DEGREES AFTER SATURDAY.  11

.PSR...NONE.

In the hours before

Special weather statement, Jul 9, 12:45 PM MST, 4 hours 56 minutes before

AZZ022>024-027-028-100400-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE PHOENIX AZ
1245 PM MST TUE JUL 9 2002

...HAZARDOUS WEATHER POSSIBLE OVER PORTIONS OF SOUTH-CENTRAL ARIZONA
FROM 3 PM TODAY UNTIL MIDNIGHT TONIGHT...

COUNTIES IN SOUTH-CENTRAL ARIZONA IN THE RISK AREA INCLUDE...
     MARICOPA...NORTHWEST PINAL AND SOUTHERN GILA.

THE PHOENIX METROPOLITAN AREA IS INCLUDED IN THE OUTLOOK...BUT
MAINLY AFTER 700 PM.

THE PRIMARY HAZARDOUS WEATHER RISKS INCLUDE: THUNDERSTORMS
     WITH STRONG AND DAMAGING WINDS TO OVER 50 MPH ALONG
     WITH BLOWING DUST ON THE DESERTS LOWERING VISIBILITIES TO
     LESS THAN ONE-QUARTER MILE.

ADDITIONAL THREATS INCLUDE: BRIEF HEAVY RAINFALL AND DEADLY
     LIGHTNING.

STORM SPOTTER ACTIVATION MAY BE NECESSARY LATER TODAY.

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 9, 5:14 PM MST	Severe Thunderstorm Warning	PSR	Pinal	31 min
Jul 9, 5:44 PM MST	Severe Thunderstorm Warning	PSR	Maricopa, Pinal	46 min
Jul 9, 6:18 PM MST	Severe Thunderstorm Warning	PSR	Pinal	42 min
Jul 9, 7:28 PM MST	Severe Thunderstorm Warning	PSR	Maricopa, Pinal	17 min
Jul 9, 7:29 PM MST	Severe Thunderstorm Warning	PSR	Maricopa, Pinal	31 min
Jul 9, 7:35 PM MST	Severe Thunderstorm Warning	PSR	Maricopa, Pinal	25 min
Jul 9, 7:39 PM MST	Severe Thunderstorm Warning	PSR	Maricopa, Pinal	21 min
Jul 9, 8:09 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	36 min
Jul 9, 8:21 PM MST	Severe Thunderstorm Warning	PSR	Maricopa	39 min

Nearby

Severe Thunderstorm Warnings in Arizona, 2002 Every severe thunderstorm warning in 2002

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.