Alert archive / Arizona / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 7, NWS Phoenix, AZ

July 3, 2001Maricopa County, Arizona

NWS Phoenix, AZ issued this severe thunderstorm warning at Jul 3, 2001, 7:59 PM MST for Maricopa County, Arizona. It was in force for 61 min. 1 report came from inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties, with what was reported inside it.

The facts

Issued
Jul 3, 2001, 7:59 PM MST (02:59 UTC)
Expired
Jul 3, 2001, 9:00 PM MST
In force
61 min
Issued by
NWS Phoenix, AZ
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Maricopa County, AZ

The radar

The Phoenix radar (KIWA), 109 km from the middle of the area, began a volume at 03:02 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

TimeReportWhereRemark
Jul 3, 8:16 PM MSTThunderstorm Wind 63 MPhoenix, AZWinds gusted to 63 mph at the Palo Verde Nuclear Generating Station.

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.

The nearest sounding before it

Phoenix, AZ (KPSR), launched 00:00Z, 3.0 hours before the alert went out and 79 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 00:00Z on 2001-07-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 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 00:00Z on 2001-07-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 9 square meters per square second.1939Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3684 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
9 m²/s²
0-3 km storm-relative helicity
98 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 040300
SVRPHX

AZC013-040400-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
759 PM MST TUE JUL 3 2001

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

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

* UNTIL 900 PM MST

* AT 752 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 15 MILES NORTHEAST OF WINTERSBURG...OR ABOUT 10
  MILES NORTH OF BUCKEYE...MOVING WEST AT 25 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  WINTERSBURG AT 820 PM MST
  TONOPAH AT 825 PM MST
  AND INTERSTATE 10

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 3344 11260 3362 11260 3366 11314 3336 11314

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 3, 4:05 PM MST, 3 hours 54 minutes earlier.

Area forecast discussion, Jul 3, 4:05 PM MST, 3 hours 54 minutes before
AZZ020>028-CAZ030>033-040545-

SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
405 PM MST TUE JUL 3 2001

.SYNOPSIS...
A LARGE HIGH PRESSURE SYSTEM ALOFT...CENTERED OVER THE GREAT BASIN
...WILL DRIFT SLOWLY EASTWARD THIS WEEK. THIS WILL RESULT IN
SOUTHEASTERLY WIND FLOW BRINGING MORE MOISTURE TO BOTH SOUTHEAST
CALIFORNIA AND SOUTHWEST ARIZONA. A CORRESPONDING INCREASE IN
THUNDERSTORM POTENTIAL CAN BE EXPECTED...AS THE AIR BECOMES MORE
MOIST. IT WILL...HOWEVER...TEND TO MODERATE THE DAYTIME TEMPERATURES
DOWN TO MORE NORMAL LEVELS BY MID WEEK.

.DISCUSSION...
AFTERNOON CONVECTION TAKING A SOMEWHAT UNUSUAL PATTEN WITH MORE
ACTIVITY OVER YAVAPAI AND MOHAVE COUNTIES THAN IN SOUTHEAST ARIZONA.
MEANWHILE ZONE 28 GETTING DOWNBURST STORMS DESPITE MODEST APPEARANCE
ON RADAR. LARGE STORM NORTH OF ZONE 24 A LATE BLOOMER WHICH MAY HELP
TO BRING STORM THREAT TO PHOENIX METRO AREA. ZONE 21 HAS A BETTER
THREAT GIVEN YAVAPAI/MOHAVE ACTIVITY AND STEERING FLOW.

WITH APPROACHING INVERTED TROUGH AND SHIFT TO SOUTHEASTERLY FLOW...
LOW LEVEL MOISTURE AND THUNDERSTORM ACTIVITY OVER THE CWA WILL BE ON
THE INCREASE. TEMPS WILL BE ON THE DECREASE BUT EXPECT TOMORROW TO
STILL BE QUITE WARM WITH MORE COOLING THURSDAY.

TONIGHTS STORMS WILL BE STRICTLY WIND PRODUCERS...BUT
BY THURSDAY THEY WILL TRANSITION TO PRECIP PRODUCERS. WITH MORE CAPE
THOUGH THERE WILL STILL BE SEVERE WIND THREAT WITH SOME OF THE
STORMS THURSDAY.

IN THE EXTENDED...MRF AND ECMWF SHOW WESTERLIES TRYING TO INTRUDE
FOR DRYING FROM THE WEST. ONLY WESTERN ZONES ARE LIKELY TO DRY OUT.
HOWEVER...IN THE LATTER PART OF THE EXTENDED...THE HIGH CENTER
SHIFTS WESTWARD WHICH MIGHT LEAD TO REINTRODUCTION OF MOISTURE INTO
WESTERN CWA BY TUESDAY. NOT CONFIDENT ENOUGH IN THAT SCENARIO TO
REINTRODUCE STORM POSSIBILITIES.

JAMISON

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 3, 5:53 PM MSTSevere Thunderstorm WarningPSRMaricopa37 min

Nearby

Severe Thunderstorm Warnings in Arizona, 2001Every severe thunderstorm warning in 2001

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.