Alert archive / Arizona / Severe Thunderstorm Warnings in 2003

Severe Thunderstorm Warning 23, NWS Flagstaff, AZ

July 29, 2003Yavapai County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Jul 29, 2003, 2:45 PM MST for Yavapai 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 as issued.

The facts

Issued: Jul 29, 2003, 2:45 PM MST (21:45 UTC)
Expired: Jul 29, 2003, 3:15 PM MST
In force: 30 min
Issued by: NWS Flagstaff, AZ
Area: Counties, with a storm outline in the text

County Yavapai County, AZ

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 nearest sounding before it

Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 9.8 hours before the alert went out and 77 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 217 J/kg
Mixed-layer CIN: -61 J/kg
Mixed-layer LCL: 1348 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 2 m²/s²
0-3 km storm-relative helicity: 34 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

The text

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

000 
WUUS55 KFGZ 292145
SVRFGZ
AZC025-292215-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
243 PM MST TUE JUL 29 2003

THE NATIONAL WEATHER SERVICE IN FLAGSTAFF HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL YAVAPAI COUNTY IN WEST CENTRAL ARIZONA

* UNTIL 315 PM MST

* AT 241 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM OVER CHERRY...OR ABOUT 8 MILES SOUTHWEST OF    
  COTTONWOOD...MOVING SOUTHWEST AT 5 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  THE STORM WILL BE NEAR HIGHWAY 169 BETWEEN DEWEY AND I-17 AT 310 PM
  MST

REPORT SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY. THEY
WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST
OFFICE IN FLAGSTAFF.

LAT...LON 3459 11197 3468 11206 3458 11225 3445 11211

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 Flagstaff, AZ wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 29, 2:30 PM MST, 15 minutes earlier.

Area forecast discussion, Jul 29, 2:30 PM MST, 15 minutes before

NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
230 PM MST TUE JUL 29 2003

.SYNOPSIS...THE ATMOSPHERE WILL REMAIN MOIST AND UNSTABLE THROUGH
THE COMING WEEKEND. LOOK FOR THE DAILY SHOWERS AND THUNDERSTORMS TO
CONTINUE. TEMPERATURES WILL REMAIN NEAR NORMAL.

.DISCUSSION...SCATTERED CONVECTION HAS DEVELOPED ACROSS THE CWA
THIS AFTERNOON. REGION UNDER MOIST AND UNSTABLE EASTERLY FLOW ALOFT.
EXPECT THE STORMS TO BE HEAVY RAIN PRODUCERS WITH SOME SMALL HAIL
POSSIBLE. LIKELIEST AREAS FOR THE MOST ACTIVITY WILL BE THE RIM AND
WESTERN CWA SECTIONS. WEAK VORT MAX AND ASSOCIATED UPPER LEVEL
DIVERGENCE CROSSES THE COCONINO PLATEAU THIS AFTERNOON AND MOVES
INTO LOWER COLORADO RIVER VALLEY EARLY THIS EVENING. LOCALIZED SMALL
STREAM FLOODING A POSSIBILITY.

THE MID LEVEL HIGH CENTERED OVER N CALIF IS PROGGED TO MOVE INTO
N.M. BY THURSDAY. STREAMLINE ANALYSIS SHOWS THE CWA TO REMAIN UNDER
A MOIST AND UNSTABLE FLOW. WINDS ALOFT SHIFT FROM EAST TO SOUTH
DURING THE TRANSITION. ALTHO AVN SHOWS SOME MID LEVEL DRYING AT MID
WEEK...MODELS SHOW NO DECREASE IN AVAILABLE MOISTURE. PW VALUES
REMAIN AROUND AN INCH ACROSS NORTHERN AZ. WILL CONTINUE THE STANDARD
MONSOON FCST. NO BIG FLUCTUATIONS TEMPS SEEN.

EXTENDED...MEDIUM RANGE MODELS KEEP RIDGE OVER THE REGION BUT
DISAGREE ON THE EXACT POSITION OF CENTER OF THE HIGH OVER NM/TX.
AVN HINTS AT DRIER AIR MOVING INTO WESTERN SECTIONS OF THE STATE
LATE IN THE PERIOD. IF TRUE MAY SEE DOWN SWING IN MONSOON ACTIVITY.
ATTM BELIEVE ENOUGH MOISTURE WILL LINGER OVER ENTIRE CWA FOR MENTION
OF CONVECTION EACH DAY OF THIS PERIOD. DF

.FGZ...NONE.

.CODED TEMPERATURES/POPS FOR SELECTED CITIES IN NORTHERN ARIZONA

CITY             TEMPERATURES LO/HI           PROBABILITY OF PRECIP
                 TON WED   THU     FRI        TON WED   THU     FRI
FLAGSTAFF        057/078 057/079 057/076      040 050 040 050 040 050
WINSLOW          067/090 067/092 067/089      020 030 030 040 040 030
PRESCOTT         064/089 064/089 064/086      040 040 040 040 040 040
PAGE             075/096 074/096 074/093      030 030 030 030 030 030
WINDOW ROCK      058/084 058/084 057/081      030 040 040 040 030 040
CANYON DE CHELLY 068/090 068/090 067/087      030 030 030 040 040 030
COTTONWOOD       072/100 072/100 072/097      030 030 040 030 030 030
GRAND CANYON     056/080 056/081 056/078      030 040 040 040 040 040
GREER            053/074 053/075 053/072      050 050 040 050 040 050
HEBER            058/083 058/084 058/081      040 050 040 050 040 050
JACOB LAKE       057/076 057/077 057/074      030 040 040 040 040 040
NAVAJO N.M.      062/084 062/084 061/081      030 040 040 040 040 040
PAYSON           065/094 065/094 065/091      030 030 040 030 030 030
SEDONA           070/098 070/098 070/095      040 040 040 040 040 040
SELIGMAN         063/092 063/092 063/089      030 040 040 040 040 040
SHOW LOW         065/084 065/085 065/082      040 050 040 050 050 050
ST. JOHNS        062/084 062/086 062/083      030 040 040 050 050 040
WUPATKI N.M.     070/092 070/094 070/091      030 030 040 040 040 030

Hazardous weather outlook, Jul 29, 9:45 AM MST, 5 hours before

AZZ004>018-037>040-300200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
945 AM MST TUE JUL 29 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR APACHE...COCONINO...NORTHERN
GILA...NAVAJO...AND YAVAPAI COUNTIES IN NORTHERN ARIZONA.

.DAY ONE...TODAY

THE ATMOSPHERE REMAINS VERY MOIST AND UNSTABLE. SCATTERED
THUNDERSTORMS ARE EXPECTED TO DEVELOP AGAIN TODAY. THE STRONGEST
STORMS WILL FORM OVER AREAS SOUTH OF THE RIM AND ACROSS THE SOUTHERN
LCR. SOME OF THE STORMS WILL PRODUCE HEAVY RAINFALL. THE POTENTIAL
FOR SMALL STREAM FLOODING TODAY IS MODERATE.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

LITTLE CHANGE IS SEEN IN THE MOIST AND UNSTABLE ATMOSPHERE OVER THE
REGION THROUGH THE PERIOD. THUNDERSTORMS ARE EXPECTED TO DEVELOP
EACH DAY. THERE WILL BE THE THREAT OF HEAVY RAINFALL AMOUNTS AND THE
POTENTIAL FOR SMALL STREAM FLOODING.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

DEFINITION OF HAZARDOUS WEATHER...A WEATHER EVENT POSING A THREAT
TO LIFE AND PROPERTY.

Nearby

Severe Thunderstorm Warnings in Arizona, 2003 Every severe thunderstorm warning in 2003

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.