Alert archive / Arizona / Severe Thunderstorm Warnings in 2002
Severe Thunderstorm Warning 55, NWS Phoenix, AZ
NWS Phoenix, AZ issued this severe thunderstorm warning at Sep 7, 2002, 3:27 PM MST for Maricopa County, Pinal County, Arizona. It was in force for 48 min. 2 reports came from inside the area while it was in force.
The area
The counties it named, with what was reported inside it.
The facts
- Issued
- Sep 7, 2002, 3:27 PM MST (22:27 UTC)
- Expired
- Sep 7, 2002, 4:15 PM MST
- In force
- 48 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), 29 km from the middle of the area, began a volume at 22:30 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 |
|---|---|---|---|
| Sep 7, 3:30 PM MST | Thunderstorm Wind 50 E | Maricopa, AZ | Power lines reported down on a house in Maricopa. |
| Sep 7, 4:05 PM MST | Hail 1.75 | Goodyear, AZ | Numerous reports of large hail throughout the West Valley, including Sun City, Peoria, and Phoenix. Winds to over 60 mph damaged homes, blew down power poles and uprooted trees. Streets were flooded in the West Valley as rain totals were as much as 1.85 inc |
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 |
|---|---|---|---|
| Sep 7, 1:30 PM MST | Severe Thunderstorm Watch | SPC | 7 hr |
The nearest sounding before it
Phoenix, AZ (KPSR), launched 12:00Z, 10.5 hours before the alert went out and 34 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.
- Mixed-layer CAPE
- 146 J/kg
- Mixed-layer CIN
- -210 J/kg
- Mixed-layer LCL
- 1553 m above ground
- 0-6 km bulk shear
- 34 kt
- 0-1 km storm-relative helicity
- 38 m²/s²
- 0-3 km storm-relative helicity
- 62 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
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 7, 10:25 AM MST, 5 hours 2 minutes earlier.
Area forecast discussion, Sep 7, 10:25 AM MST, 5 hours 2 minutes before
AZZ020>028-CAZ030>033-072245- SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PHOENIX AZ 1025 AM MST SAT SEP 7 2002 .SYNOPSIS... MOIST UNSTABLE AIR WILL REMAIN IN PLACE OVER FAR SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA THE NEXT FEW DAYS. UPPER LEVEL WINDS WILL REMAIN STRONGER THAN NORMAL SINCE LOW PRESSURE WILL REMAIN JUST WEST OF THE AREA WHILE A RIDGE OF HIGH PRESSURE REMAINS CENTERED OVER NEW MEXICO. A SERIES OF WEATHER DISTURBANCES WILL BRING PERIODS OF SHOWERS AND THUNDERSTORMS TO THE AREA...WITH THE GREATEST CHANCE FOR STORMS AND LOCALLY HEAVY RAIN OVER SOUTH-CENTRAL ARIZONA. SOMEWHAT DRIER AIR MAY MOVE INTO SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA BY THE MIDDLE OF NEXT WEEK. TEMPERATURES WILL BE NEAR SEASONAL NORMALS THE NEXT FEW DAYS. .DISCUSSION... ACTIVE WEATHER PATTERN REMAINS IN PLACE OVER THE FORECAST AREA THIS MORNING. ABUNDANT MOISTURE EXISTS PER GOES PW IMAGES AND MORNING SOUNDINGS...WITH PW 1.5-1.75. RATHER STRONG MID-UPPER LEVEL DISTURBANCE OVER SOUTHEAST CALIFORNIA-FAR SOUTHERN NEVADA IS LIFTING TOWARD THE NORTHEAST...WITH LOW-MID LEVEL CONVERGENCE ON TAIL END OF DISTURBANCE OVER SOUTHWEST AZ ATTM. ASSOCIATED ASCENT WITH THIS DISTURBANCE HAS ALREADY LED TO INTENSE THUNDERSTORM DEVELOPMENT ...WITH ISOLATED SEVERE STORMS CURRENTLY AFFECTING PORTIONS OF NORTHWEST MARICOPA COUNTY. APPEARS THIS PARTICULAR AREA OF STORMS WILL REMAIN PRIMARILY TO THE NORTHWEST OF THE GREATER PHOENIX AREA...BUT MORE STORMS WILL BE DEVELOPING OVER THE AREA TODAY. NEARLY THE ENTIRE PHX AREA RECEIVED MEASURABLE RAIN FRIDAY AFTERNOON AND NIGHT...AND MORNING PHX SOUNDING WAS MUCH COOLER IN LOWER LEVELS ...WHICH HAS RESULTED IN MUCH LOWER CAPE. HOWEVER...WITH UPPER LEVEL FORCING...ABUNDANT MOISTURE...AND EXPECTED DAYTIME HEATING INTO THE MID 90S...SEE NO NEED TO BACK OFF FROM INHERITED FORECAST... INCLUDING FLASH FLOOD WATCH FOR SOUTH CENTRAL AZ THIS AFTERNOON THROUGH MIDNIGHT...AND THREAT FOR SEVERE THUNDERSTORMS WILL BE PRESENT AS WELL TODAY AND THIS EVENING. DG .PSR...FLASH FLOOD WATCH NOON TODAY THROUGH MIDNIGHT TONIGHT FOR S CENTRAL AZ...MARICOPA...N CENTRAL PINAL...AND SOUTHERN GILA COUNTIES ...FCST AZ ZONES...22...23...24...27...AND 28.
In the hours before
Special weather statement, Sep 7, 11:30 AM MST, 3 hours 57 minutes before
AZZ021>024-026>028-080000- HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE PHOENIX AZ 1130 AM MST SAT SEP 7 2002 ...A RISK OF STRONG THUNDERSTORMS AND HAZARDOUS WEATHER OVER PORTIONS OF SOUTHWEST AND SOUTH-CENTRAL ARIZONA THIS AFTERNOON AND EVENING... THE OUTLOOK AREA CONSISTS OF THE FOLLOWING COUNTIES IN ARIZONA... MARICOPA...NORTHERN PINAL...SOUTHERN GILA...LA PAZ AND YUMA. CITIES AND TOWNS IN THE OUTLOOK AREA INCLUDE...THE GREATER PHOENIX METROPOLITAN AREA...CASA GRANDE...FLORENCE...COOLIDGE...GILA BEND... WICKENBURG...WENDEN...AND DATELAND. THE PRIMARY HAZARDOUS WEATHER RISK OVER THIS OUTLOOK AREA IS LOCALLY HEAVY RAIN. A FLASH FLOOD WATCH HAS BEEN POSTED FOR SOUTH CENTRAL ARIZONA FROM NOON UNTIL MIDNIGHT TONIGHT. IN ADDITION TO HEAVY RAIN...LARGE HAIL...STRONG AND DAMAGING WINDS IN EXCESS OF 50 MPH...AND AREAS OF BLOWING DUST THAT COULD LOWER VISIBILITY TO UNDER ONE HALF MILE WILL BE POSSIBLE WITH AND NEAR THE STRONGEST STORMS. STORM SPOTTER ACTIVATION MAY BE NECESSARY THIS AFTERNOON AND EVENING. DG
The office that day
Everything else NWS Phoenix, AZ issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 6, 5:15 PM MST | Severe Thunderstorm Warning | PSR | Maricopa | 45 min |
| Sep 6, 7:08 PM MST | Severe Thunderstorm Warning | PSR | Maricopa | 37 min |
| Sep 6, 7:13 PM MST | Severe Thunderstorm Warning | PSR | Maricopa | 32 min |
| Sep 6, 11:19 PM MST | Severe Thunderstorm Warning | PSR | Maricopa | 56 min |
| Sep 7, 10:13 AM MST | Severe Thunderstorm Warning | PSR | Maricopa | 47 min |
| Sep 7, 2:38 PM MST | Severe Thunderstorm Warning | PSR | La Paz | 37 min |
| Sep 7, 2:45 PM MST | Severe Thunderstorm Warning | PSR | Pinal | 45 min |
| Sep 7, 3:14 PM MST | Severe Thunderstorm Warning | PSR | La Paz | 46 min |
| Sep 7, 3:57 PM MST | Tornado Warning | PSR | Maricopa | 48 min |
| Sep 7, 3:57 PM MST | Tornado Warning | PSR | Maricopa | 48 min |
| Sep 7, 4:08 PM MST | Severe Thunderstorm Warning | PSR | Pinal | 37 min |
| Sep 7, 4:43 PM MST | Severe Thunderstorm Warning | PSR | Maricopa | 47 min |
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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.