Alert archive / Arizona / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 20, NWS Phoenix, AZ

August 11, 2001Maricopa County, Arizona

NWS Phoenix, AZ issued this severe thunderstorm warning at Aug 11, 2001, 5:15 PM MST for Maricopa County, Arizona. It was in force for 30 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 11, 2001, 5:15 PM MST (00:15 UTC)
Expired: Aug 11, 2001, 5:45 PM MST
In force: 30 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), 91 km from the middle of the area, began a volume at 00:18 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 text

As transmitted, in the capitals the NWS used until 2016.

995 
WUUS55 KPSR 120019
SVRPHX
AZC013-120045-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
515 PM MST SAT AUG 11 2001

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL MARICOPA COUNTY IN SOUTH CENTRAL ARIZONA
  THE WARNING AREA INCLUDES THE WHITE TANK MOOUNTAIN REGIONAL PARK   
  AND SUNVALLEY PARKWAY JUST WEST OF THE WHITE TANK PARK. 

* UNTIL 545 PM MST

* AT 500 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 16 MILES NORTH OF BUCKEYE...OR ABOUT 13 MILES
  SOUTHWEST OF WITTMANN...MOVING SOUTH AT 20 MPH.

DAMAGING MICROBURST WINDS ARE LIKELY WITH THIS STORM. VERY HEAVY RAIN
IS ALSO POSSIBLE. TAKE COVER IN A SUBSTANTIAL SHELTER UNTIL THE STORM
PASSES.

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 3361 11252 3363 11274 3326 11281 3324 11254

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 11, 2:45 PM MST, 2 hours 30 minutes earlier.

Area forecast discussion, Aug 11, 2:45 PM MST, 2 hours 30 minutes before

AZZ020>028-CAZ030>033-120545-

SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
245 PM MST SAT AUG 11 2001

.SYNOPSIS...
A VERY MOIST AIRMASS WILL CONTINUE ACROSS SOUTH-CENTRAL ARIZONA THIS
WEEKEND AND INTO EARLY NEXT WEEK...WITH LESSER AMOUNTS OF MOISTURE
EXPECTED OVER FAR SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA. THIS
MEANS THAT THERE WILL BE A CHANCE OF THUNDERSTORMS OVER SOUTH-CENTRAL
ARIZONA...MAINLY DURING THE AFTERNOON AND EARLY NIGHTTIME HOURS.
HIGH PRESSURE WILL BECOME ESTABLISHED NEAR THE FOUR CORNERS EARLY
NEXT WEEK. THIS WILL GIVE A MORE EASTERLY FLOW ALOFT WHICH WILL
SERVE TO PUSH DEEPER MOISTURE FURTHER WEST...FOR BETTER CHANCES OF
STORMS ALONG AND WEST OF THE COLORADO RIVER AFTER SUNDAY.

.DISCUSSION...
MODELS REMAIN IN AGREEMENT. UPPER HIGH OVER SOUTHERN CA HAS BEEN
MOVING NORTH TOWARD SOUTHERN NV TODAY AND WILL CONTINUE INTO 4
CORNERS REGION ON SUNDAY. UPPER FLOW TO SHIFT FROM NORTH TO
NORTHEASTERLY TONIGHT AS UPPER HIGH MOVES INTO SOUTHERN NV. AIRMASS
OVER SOUTH CENTRAL AZ REMAINS MOIST WITH MORNING PHX RAOB SHOWING A
LITTLE UNDER 2 INCHES OF P WATER...ONLY SLIGHT LESS THAN FRI. THUS
THERE WILL BE A CHANCE OF THUNDERSTORMS TONIGHT IN SOUTH CENTRAL AZ
AS ACTIVITY NOW OVER AND IN VICINITY OF THE RIM REGION MAY MOVE DOWN
INTO SOUTH CENTRAL AZ THIS EVENING AND TONIGHT AS THE FLOW BECOMES
NORTHEASTERLY. IN ADDITION...THERE IS A VORTMAX IN VICINITY OF WHITE
MOUNTAINS TONIGHT TO ENHANCE THUNDERSTORMS TOWARD SOUTH CENTRAL AZ.
PLUS A WAVE IN NORTHERN MEXICO INTO SE AZ. WITH THE DEEP MOISTURE
OVER SOUTHERN GILA COUNTY SOME STORMS MAY PRODUCE LOCALLY HEAVY
RAINFALL.  DRIER WESTERLY FLOW OVER SE CA TO KEEP THAT AREA MOSTLY
CLEAR TONIGHT AND SUNDAY. FLOW TO BECOME MORE EAST TO SOUTHEASTERLY
SUNDAY AS UPPER HIGH REACHES 4 CORNERS AREA. WITH MOIST AIRMASS OVER
NM...THE EAST FLOW WILL KEEP SOUTH CENTRAL AZ MOIST ALONG WITH
CHANCE OF THUNDERSTORMS. THIS MOIST EAST FLOW EXPECTED TO REACH SE
CA BY LATE SUNDAY/MONDAY FOR PARTLY CLOUDY SKIES AND CHANCE OF
THUNDERSTORMS BY MONDAY AND THEREAFTER. IN ADDITION AVN MOVES
NORTHERN MEXICAN WAVE WESTWARD ALONG AZ SOUTHERN BORDER INTO THE
NORTHERN GULF BY SUNDAY NIGHT / MONDAY. THIS ALONG WITH THE WESTWARD
PUSH OF MOISTURE WILL BRING A CHANCE FOR THUNDERSTORMS INTO FAR SW
AZ AND SE CA.   EXTENDED MRF SHOWS LITTLE CHANGE AS MOIST FLOW TO
REMAIN THROUGH EXTENDED PERIOD FOR PARTLY CLOUDY SKIES AND CHANCE OF
THUNDERSTORMS OVER REGION. DKS

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 11, 9:10 PM MST	Severe Thunderstorm Warning	PSR	La Paz, Yuma	35 min
Aug 11, 10:19 PM MST	Severe Thunderstorm Warning	PSR	Yuma	41 min
Aug 11, 10:30 PM MST	Flash Flood Warning	PSR	Yuma
Aug 12, 2:12 PM MST	Severe Thunderstorm Warning	PSR	Maricopa, Yuma	48 min

Nearby

Severe Thunderstorm Warnings in Arizona, 2001 Every 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; radar from the NEXRAD Level II archive.