Alert archive / Arizona / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 72, NWS Phoenix, AZ

October 17, 2002Pinal County, Arizona

NWS Phoenix, AZ issued this severe thunderstorm warning at Oct 17, 2002, 3:54 PM MST for Pinal County, Arizona. It was in force for 36 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
Oct 17, 2002, 3:54 PM MST (22:54 UTC)
Expired
Oct 17, 2002, 4:30 PM MST
In force
36 min
Issued by
NWS Phoenix, AZ
Area
Counties, with a storm outline in the text

County Pinal County, AZ

The radar

The Phoenix radar (KIWA), 30 km from the middle of the area, began a volume at 22:53 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

Tuscon, AZ (KTUS), launched 12:00Z, 10.9 hours before the alert went out and 129 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, Tuscon, AZ at 12:00Z on 2002-10-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 297 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, Tuscon, AZ at 12:00Z on 2002-10-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 48 square meters per square second.1939587897117Sfc1 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
297 J/kg
Mixed-layer CIN
-50 J/kg
Mixed-layer LCL
1643 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
48 m²/s²
0-3 km storm-relative helicity
146 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.

893 
WUUS55 KPSR 172254
SVRPSR
AZC021-172330-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
350 PM MST THU OCT 17 2002

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

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

* UNTIL 430 PM MST

* AT 338 PM MST...THE PUBLIC REPORTED A SEVERE THUNDERSTORM BETWEEN 
QUEEN CREEK AND FLORENCE JUNCTION...MOVING NORTH AT 20 MPH.

VERY 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.

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 3313 11157 3308 11124 3326 11098 3346 11107
          3347 11146 3336 11155

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 Oct 17, 3:05 PM MST, 49 minutes earlier.

Area forecast discussion, Oct 17, 3:05 PM MST, 49 minutes before
AZZ020>028-CAZ030>033-180545-

SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
305 MST THU OCT 17 2002

.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL MOVE INTO SOUTH CENTRAL ARIZONA TONIGHT.
THE SHOWERS AND THUNDERSTORMS WILL CONTINUE TO BE MOST NUMEROUS OVER
THE HIGHER TERRAIN OF SOUTH CENTRAL ARIZONA. AS THE LOW MOVES INTO
NEW MEXICO TOMORROW...CLEARING SKIES WILL SPREAD FROM WEST TO EAST.
DRIER AIR...WITH MORE SUNSHINE IS EXPECTED FOR THE WEEKEND...HOWEVER
A WEAK LOW PRESSURE AREA WILL REMAIN OVER THE EASTERN PACIFIC FOR
SOME CLOUDS FROM TIME TO TIME NEXT WEEK.

.DISCUSSION...
STRONG UPPER LOW MOVED ACROSS SE CALIF TODAY...WITH BEST DYNAMICS
AND MOISTURE FIELDS COMBINING FOR SHOWERS AND TSTMS EARLIER TODAY.
THE LOW AND MID LEVEL MSTR INCREASED A BIT...BUT BY EARLY THIS
AFTERNOON...SOME DECREASE IN DEW POINTS HAD TAKEN OVER AND THERE WAS
SOME LIMIT OR CAP ON THE DEPTH OF CONVECTION. POSSIBLE FRONTAL
BOUNDARY ALSO ANALYZED BTWN YUMA AND PHOENIX THIS AFTN. COVERAGE OF
SHOWERS AND TSTMS WAS INCREASED TO SCATTERED...FROM ABOUT GILA BEND
EASTWARD.  SMALL BANDS OR CLUSTERS OF SHOWERS/TSTMS MAY STILL FORM
WITH THE COLDEST AIR ALOFT...-20C AT 500MB.  WE SHOULD BE ABLE TO
GET SOME 1/4 INCH TO LCLLY 1/2 INCH AMOUNTS AS THE LOW SLOWLY FILLS
BY 12Z FRIDAY.

PCPN SHOULD SLOWLY TAPER OFF FROM WEST TO EAST ON FRIDAY...BUT THERE
WILL STILL BE SOME WRAP AROUND MSTR MAINLY IN ZONE 24 ON  FRI NIGHT.
THE COOLER AIR WILL BE SEEN IN SOME ZONES FRIDAY NIGHT...UNDER CLEAR
SKIES BUT LITTLE DAY TO DAY TEMP CHANGES THEREAFTER AS HIGH LEVEL
MSTR RACES INTO AZ UNDER THE CANADIAN BLOCK NEXT WEEK. WILL NOT
MENTION ANY PRECIPITATION AT THIS TIME.  SIPPLE

.PSR...NONE.
Hazardous weather outlook, Oct 17, 8:50 AM MST, 7 hours 4 minutes before
AZZ020>028-CAZ030>033-180100-

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE PHOENIX AZ
850 AM MST THU OCT 17 2002

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

.DAY ONE... TODAY

AN UPPER LOW PRESSURE SYSTEM MOVING THROUGH SOUTHERN ARIZONA WILL
HELP TO PRODUCE SCATTERED THUNDERSTORMS MAINLY FROM LATE THIS
MORNING THROUGH THE AFTERNOON HOURS. THE MOST LIKELY AREAS FOR
STRONG STORMS WILL BE FROM THE ARIZONA SOUTH-CENTRAL DESERTS
EASTWARD. THE MAIN THREAT FROM THESE STORMS WILL BE LARGE
HAIL...STRONG...GUSTY WINDS AND LOCALLY HEAVY RAINFALL.

.INSTRUCTIONS TO SPOTTERS...

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

.DAYS TWO THROUGH SEVEN... FRIDAY THROUGH WEDNESDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

ESTLE

Nearby

Severe Thunderstorm Warnings in Arizona, 2002Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.