Alert archive / Arizona / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 14, NWS Phoenix, AZ

August 3, 2001Maricopa County, Arizona

NWS Phoenix, AZ issued this severe thunderstorm warning at Aug 3, 2001, 7:38 PM MST for Maricopa County, Arizona. It was in force for 37 min. No storm report in the archive falls 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.

The facts

Issued
Aug 3, 2001, 7:38 PM MST (02:38 UTC)
Expired
Aug 3, 2001, 8:15 PM MST
In force
37 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), 46 km from the middle of the area, began a volume at 02:37 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.

The nearest sounding before it

Tuscon, AZ (KTUS), launched 00:00Z, 2.6 hours before the alert went out and 159 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 00:00Z on 2001-08-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 483 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 00:00Z on 2001-08-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -4 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
483 J/kg
Mixed-layer CIN
-90 J/kg
Mixed-layer LCL
2515 m above ground
0-6 km bulk shear
5 kt
0-1 km storm-relative helicity
-4 m²/s²
0-3 km storm-relative helicity
39 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 040241
SVRPHX

AZC013-040315-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
738 PM MST FRI AUG 3 2001

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

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

* UNTIL 815 PM MST.

* AT 738 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM OVER EXTREME EAST CENTRAL MARICOPA COUNTY OVER 
  APACHE LAKE. OR ABOUT 8 MILES SOUTHWEST OF ROOSEVELT....

MICROBURST WINDS OF 60 MILES PER HOUR ARE LIKELY WITH THIS STORM. 
BOATERS ON APACHE LAKE SHOULD SEEK SHELTER IMMEDIATELY. 

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 3356 11143 3348 11131 3355 11108 3366 11123

AJ

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 Aug 3, 10:07 AM MST, 9 hours 31 minutes earlier.

Area forecast discussion, Aug 3, 10:07 AM MST, 9 hours 31 minutes before
AZZ020>028-CAZ030>033-032245-

SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
1007 AM MST FRI AUG 3 2001

.SYNOPSIS...
STRONG HIGH PRESSURE WILL REMAIN OVER THE CENTRAL UNITED STATES FOR
THE NEXT COUPLE OF DAYS...THEN WILL MOVE OVER THE NORTHERN ROCKIES
BY EARLY NEXT WEEK. AN EASTERLY FLOW ALOFT...COUPLED WITH ABUNDANT
MOISTURE...WILL BRING A CHANCE FOR MAINLY AFTERNOON AND NIGHTTIME
THUNDERSTORMS OVER SOUTH-CENTRAL ARIZONA TODAY AND SATURDAY...THEN
OVER MOST OF SOUTHWEST AND SOUTH-CENTRAL ARIZONA...AS WELL AS PART
OF SOUTHEAST CALIFORNIA...BY SUNDAY AND ON INTO THE MIDDLE OF NEXT
WEEK.

.DISCUSSION...
SEEMS LIKE A LITTLE SUBSIDENCE AND MINOR DRYING HAS MOVED OVER SRN
AZ THIS MORNING. SURFACE DEWPOINTS ARE GENERALLY DOWN SOME...WHILE
TEMPS ARE UP...LOTS OF SUNSHINE. MINOR IMPULSE MOVED NWD ACROSS THE
AREA LAST NIGHT AND EARLY THIS MORNING...BUT DID LITTLE TO ENHANCE
CONVECTION IN THE AREA. DID GET A LITTLE RAIN HERE AND THERE...BUT
OVERALL A DUD. SOUNDINGS THIS MORNING SHOW THE ATMOSPHERE WAS NOT
AFFECTED TOO MUCH BY WHAT ACTIVITY THERE WAS...SO NO PROBLEM IN A
RELOAD. STABILITY PARAMETERS APPEAR MORE FAVORABLE TODAY THAN THEY
HAVE BEEN...BUT MOISTURE IS DOWN A LITTLE. H5 RIDGE AXIS NOT IN A
FAVORABLE POSITION FOR THE PHX CWA...TOO FAR S...AND THE FLOW WILL
BE TENDING TOWARD SWLY AS THE INVERTED TROUGH OVER NRN AZ MOVES
FARTHER N LATER TODAY. THIS IS NOT GOOD IF WE WANT STORMS AND RAIN.
AS THE PREVIOUS FORECASTER MENTIONED...STORMS MAY BECOME ORGANIZED
OVER SRN AZ LATE THIS AFTN AND EVE IN A REGION OF LOW INERTIAL
STABILITY AND UPPER DIFLUENCE...ALBEIT WEAK DIFLUENCE. OUTFLOW FROM
THOSE STORMS COULD HELP TO TRIGGER SOME STORMS OVER PARTS OF THE PHX
CWA TONIGHT. THEREFORE...WILL STAY WITH THE GENERAL POPS ALREADY
FORECAST...WHICH ARE GENERALLY CLIMO-TYPE POPS....FOR TONIGHT AND
BEYOND. HOWEVER...MAY UPDATE THE FORECAST TO TAKE OUT MENTION OF
STORMS IN THE PHX METRO AREA THIS AFTERNOON...AS EXPECT A BIT OF A
DELAYED START TODAY DUE TO SUBSIDENCE MENTIONED EARLIER. H5 HEIGHTS
MAY DROP A BIT SAT AS THE CNTRL US ANTICYCLONE DRIFTS NWD...SO
CONVECTION COULD BE MORE PREVALENT SAT AFTN AND EVE...ESPECIALLY
OVER S-CNTRL AZ. PROBLEM OF HOW FAR W TO CARRY THE STORMS IS STILL A
CONSIDERATION IN EXTENDED FORECAST. GENERAL PATTERN SUGGESTS SOME
ACTIVITY MAY EXTEND INTO SERN CA AT TIMES. FOR NOW...WILL LEAVE THE
EXTENDED AS IS.  WILT

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.