Alert archive / Arizona / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 35, NWS Tucson, AZ

August 10, 2001Graham County, Arizona

NWS Tucson, AZ issued this severe thunderstorm warning at Aug 10, 2001, 5:43 PM MST for Graham County, Arizona. It was in force for 47 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 10, 2001, 5:43 PM MST (00:43 UTC)
Expired
Aug 10, 2001, 6:30 PM MST
In force
47 min
Issued by
NWS Tucson, AZ
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Graham County, AZ

The radar

The Tucson radar (KEMX), 119 km from the middle of the area, began a volume at 00:45 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, 0.7 hours before the alert went out and 115 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 2001-08-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1274 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 2001-08-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 36 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
1274 J/kg
Mixed-layer CIN
-13 J/kg
Mixed-layer LCL
1715 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
36 m²/s²
0-3 km storm-relative helicity
61 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.

016 
WUUS55 KTWC 110042
SVRTUS
AZC009-110130-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TUCSON AZ
543 PM MST FRI AUG 10 2001

THE NATIONAL WEATHER SERVICE IN TUCSON HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN GRAHAM COUNTY IN ARIZONA
  THIS INCLUDES SAFFORD

* UNTIL 630 PM MST

* AT 540 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR             
  INDICATED SEVERE THUNDERSTORMS 11 MILES SOUTH AND 10 MILES         
  WEST OF SAFFORD. STORMS HAVE A HISTORY OF PRODUCING TORRENTIAL RAIN
  AND WIND GUSTS TO NEAR 80 MPH. 

REMEMBER...A SEVERE THUNDERSTORM CAN PRODUCE LARGE HAIL...DAMAGING
WINDS IN EXCESS OF 55 MPH...DEADLY LIGHTNING...AND HEAVY RAIN.

LAT...LON 3287 11011 3254 11012 3256 10955 3293 10952

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 Tucson, AZ wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 10, 2:20 PM MST, 3 hours 23 minutes earlier.

Area forecast discussion, Aug 10, 2:20 PM MST, 3 hours 23 minutes before
SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
220 PM MST FRI AUG 10 2001

.SYNOPSIS...AMPLE MOISTURE AND AN UPPER LEVEL DISTURBANCE MOVING
ACROSS NORTHERN ARIZONA WILL PROVIDE SCATTERED SHOWERS AND
THUNDERSTORMS TO MUCH OF SOUTHEAST ARIZONA TONIGHT. LIGHT WINDS
ALOFT IN COMBINATION WITH THE AMPLE MOISTURE WILL LEAD TO LOCALLY
HEAVY RAINFALL. HIGH PRESSURE ALOFT WILL BECOME CENTERED NEAR THE
FOUR CORNERS DURING THE WEEKEND. THIS FEATURE WILL BRING A NORTHEAST
TO EAST UPPER LEVEL WIND FLOW TO SOUTHEAST ARIZONA. THIS FLOW WILL
LEAD TO AN INCREASING CHANCE OF MAINLY AFTERNOON AND EVENING SHOWERS
AND THUNDERSTORMS INTO EARLY NEXT WEEK.

.DISCUSSION...SHOWERS AND THUNDERSTORMS CONTINUE TO DEVELOP AT THIS
TIME ACROSS MAINLY THE CENTRAL CWA...EAST OF A DUDLEYVILLE...TO
TUCSON...TO NOGALES LINE. SOUNDINGS FROM THIS MORNING INDICATE AN
EXTREMELY MOIST BUT MARGINALLY UNSTABLE ATMOSPHERE WITH PRECIPITABLE
WATER VALUES NEAR 2 INCHES. THE MAIN CONCERN THIS EVENING/TONIGHT IS
FOR HEAVY RAIN AND FLASH FLOODING. A SHORT WAVE TROUGH OVER NRN AZ
IS EXPECTED TO INCREASE ATMOSPHERIC LIFT TONIGHT. AM CONCERNED ABOUT
DEVELOPMENT ON THE RIM AND MOUNTAINS EAST OF TUCSON. ORGANIZATION
APPEARS LOOSE AT THIS TIME...HOWEVER EVENING SHIFT WILL NEED TO
MONITOR FOR CONSOLIDATION AND ADDITIONAL DEVELOPMENT. WILL MENTION
LOCALLY HEAVY RAINS IN ALL EXCEPT WRN ZONES WHERE ISOLATED
THUNDERSTORMS SHOULD PREVAIL. APPEARS SATURDAY WILL BE A DOWN-DAY AS
HIGH PRESSURE OVER NWRN AZ REPOSITIONS TOWARD THE FOUR CORNERS.
GENERIC LOW-GRADE MONSOON POPS TO RULE. ELY FLOW PROGGED TO INCREASE
SUN. THIS SCENARIO WILL PROVIDE AN INCREASED CHANCE OF SHOWERS AND
THUNDERSTORMS INTO EARLY NEXT WEEK. NO CHANGES TO THE EXTENDED
PERIOD.  BF

.TWC...NONE.

In the hours before

Special weather statement, Aug 10, 11:45 AM MST, 5 hours 58 minutes before
AZZ019-029>035-110700-

SOUTHEAST ARIZONA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1145 AM MST FRI AUG 10 2001

.SYNOPSIS...THERE HAS BEEN LITTLE CHANGE IN THE WEATHER PATTERN
SINCE YESTERDAY. UPPER LEVEL HIGH PRESSURE REMAINS OVER NORTHWEST
ARIZONA...WITH A WEAKENING TROUGH OF LOW PRESSURE OVER NEW MEXICO
AND AN UPPER LEVEL DISTURBANCE PASSING ALONG THE ARIZONA-UTAH
BORDER. EXTENSIVE CLOUD COVER WILL KEEP INSTABILITY LIMITED...BUT
THE ATMOSPHERE WILL REMAIN VERY MOIST OVER THE REGION.

.DISCUSSION...A MESOSCALE CONVECTIVE SYSTEM WHICH DEVELOPED OVER THE
WESTERN MOGOLLON RIM LATE LAST NIGHT MOVED SOUTH ACROSS WESTERN
PINAL AND CENTRAL PIMA COUNTIES THIS MORNING. THE CLOUD COVER FROM
THIS COMPLEX SPREAD ACROSS ALL BUT THE FAR WESTERN AND EASTERN
PORTIONS OF THE AREA...BUT WAS THINNING OUT JUST BEFORE NOON.
SOUNDINGS FROM THIS MORNING INDICATE AN EXTREMELY MOIST BUT
MARGINALLY UNSTABLE ATMOSPHERE WITH PRECIPITABLE WATERS NEAR 2
INCHES. THE LACK OF INSTABILITY WILL LIMIT THE STRENGTH OF STORM
UPDRAFTS AND KEEP THE RISK OF SEVERE STORMS TO A MINIMUM. THE RISK
IS SLIGHTLY HIGHER OVER GRAHAM AND COCHISE COUNTIES WHERE A
TEMPERATURE CONTRAST HAS DEVELOPED BETWEEN THE CLOUDY SKIES NEAR
TUCSON AND CLEAR SKIES FURTHER EAST.

THE RISK FOR FLASH FLOODING...HOWEVER...IS CONSIDERABLY HIGHER THAN
CLIMATOLOGY ALONG THE RIM AND EAST OF TUCSON. AN UPPER LEVEL
DISTURBANCE CURRENTLY CROSSING NORTHERN ARIZONA IS EXPECTED TO
INCREASE ATMOSPHERIC LIFT TONIGHT. THIS DISTURBANCE HAS ALREADY
BEGUN TO IGNITE THUNDERSTORMS ON THE RIM AND MOUNTAINS EAST OF
TUCSON...WITH THE HELP OF A LITTLE MORE SUNSHINE. ALTHOUGH THEY
SHOULD REMAIN DISORGANIZED...ANY OF THESE STORMS COULD PRODUCE 2
INCHES OF RAIN PER HOUR. WE WILL CLOSELY MONITOR THE RIM THIS
AFTERNOON FOR POSSIBLE ORGANIZATION. IF STORMS UP THERE CONSOLIDATE
INTO A THUNDERSTORM COMPLEX AND START TO SHIFT SOUTH...A FLASH FLOOD
WATCH MAY BECOME NECESSARY. OTHER STORMS SHOULD REDEVELOP LATE THIS
AFTERNOON FROM TUCSON WEST. THEIR SLOW MOVEMENT WILL INCREASE THE
THREAT OF FLASH FLOODING SLIGHTLY ABOVE CLIMATOLOGY...BUT THE MORE
STABLE ATMOSPHERE WILL LIMIT THEIR STRENGTH AND KEEP ADDITIONAL
HEAVY RAINS ISOLATED.

STORM MOTION WILL BE GENERALLY SOUTHWEST AT 5 MPH. HOWEVER...SOME
CELL MERGERS AND COLLISIONS COULD OCCUR WHICH WOULD MAKE SOME STORMS
APPEAR STATIONARY.

PYTLAK
Local storm report, Aug 10, 5:12 PM MST, 31 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TUCSON ARIZONA
0512 PM MST FRI AUG 10 2001

TIME (MST) .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0503 PM    SAFFORD                   AZ   79 MPH TSTM GUST
08/10/01   GRAHAM                         SAFFORD AIRPORT

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 10, 5:04 PM MSTSevere Thunderstorm WarningTWCGraham41 min
Aug 10, 5:22 PM MSTFlash Flood WarningTWCGraham
Aug 10, 5:22 PM MSTFlash Flood WarningTWCGraham8 min
Aug 11, 4:23 PM MSTSevere Thunderstorm WarningTWCPima52 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.