Alert archive / Arizona / Severe Thunderstorm Warnings in 2003

Severe Thunderstorm Warning 83, NWS Flagstaff, AZ

September 1, 2003Yavapai County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Sep 1, 2003, 5:12 PM MST for Yavapai County, Arizona. It was in force for 48 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: Sep 1, 2003, 5:12 PM MST (00:12 UTC)
Expired: Sep 1, 2003, 6:00 PM MST
In force: 48 min
Issued by: NWS Flagstaff, AZ
Area: Counties, with a storm outline in the text

County Yavapai County, AZ

The radar

The Flagstaff radar (KFSX), 77 km from the middle of the area, began a volume at 00:13 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.

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

Phoenix, AZ (KPSR), launched 00:00Z, 0.2 hours before the alert went out and 85 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: 553 J/kg
Mixed-layer CIN: -77 J/kg
Mixed-layer LCL: 2773 m above ground
0-6 km bulk shear: 10 kt
0-1 km storm-relative helicity: 8 m²/s²
0-3 km storm-relative helicity: 30 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 KFGZ 020012
SVRFGZ
AZC025-020100-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
510 PM MST MON SEP 1 2003

THE NATIONAL WEATHER SERVICE IN FLAGSTAFF HAS ISSUED A

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

* UNTIL 600 PM MST

* AT 503 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM OVER SOUTHEASTERN YAVAPAI COUNTY...ABOUT 20
  MILES NORTHEAST OF BLACK CANYON CITY...MOVING SOUTH AT 15 MPH.

* THE SEVERE THUNDERSTORM WILL REMAIN OVER RURAL SOUTHEASTERN YAVAPAI 
COUNTY EAST OF INTERSTATE 17 FROM CORDES JUNCTION TO BLACK CANYON 
CITY THROUGH 600 PM MST

HAIL UP TO 1 INCH IN DIAMETER IS POSSIBLE WITH THIS STORM. IF YOU ARE
IN THE PATH OF THE STORM...TAKE NECESSARY PRECAUTIONS AND MOVE TO A
SUBSTANTIAL SHELTER.

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 3415 11205 3411 11182 3414 11181 3426 11178
          3435 11189

$$

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 Sep 1, 2:30 PM MST, 2 hours 42 minutes earlier.

Area forecast discussion, Sep 1, 2:30 PM MST, 2 hours 42 minutes before

NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
230 PM MST MON SEP 01 2003

.SYNOPSIS.. A SOUTHEAST FLOW ALOFT WILL KEEP THE AIR MASS OVER
NORTHERN ARIZONA MOIST AND UNSTABLE THIS WEEK. AS A RESULT...LOOK
FOR SHOWERS AND THUNDERSTORMS TO DEVELOP EACH DAY.

.DISCUSSION...THUNDERSTORMS THIS AFTERNOON HAVE DEVELOPED ALONG A
CONVERGENCE ZONE FROM THE MOGOLLON RIM TO THE WHITES. ISOLATED STORMS
OVER YAVAPAI COUNTY AND THE COCONINO PLATEAU. SPOTTERS REPORT LARGE
HAIL AND HEAVY DOWNPOURS WITH A FEW OF THESE STORMS.

UPPER LEVEL HIGH PRESSURE SYSTEM TO REMAIN OVER AZ THIS WEEK. SE-S
CIRCULATION AROUND THE HIGH TO KEEP MOIST FLOW INTO THE STATE. MESO-
ETA SHOWS PLENTY OF MID LEVEL MOISTURE TO WORK WITH. EXPECT STORMS
EACH DAY...ESPECIALLY FROM THE RIM SOUTH AND WEST. DEVELOPMENT AIDED
BY INVERTED TROUGH OVER BAJA WHICH LIFTS NORTHWARD INTO AZ LATE TUE
AND WED. THIS WILL BRING INCREASED PW AND CORRESPONDING UPSWING IN
SHOWER AND THUNDERSTORM ACTIVITY. HAVE RAISED POPS ACCORDINGLY.

EXTENDED...HIGH PRESSURE OVER THE DESERT SW BEGINS TO WEAKEN BY THE
WEEKEND. APPROACHING EPAC S/WV TROF BRINGS A DRIER WESTERLY FLOW INTO
THE STATE EARLY NEXT WEEK. IF TRUE WILL SEE A DRYING AND COOLING
TREND. DF

.FGZ...NONE.

.CODED TEMPERATURES/POPS FOR SELECTED CITIES IN NORTHERN ARIZONA

CITY             TEMPERATURES LO/HI           PROBABILITY OF PRECIP
                 TON TUE   WED     THU        TON TUE   WED     THU
FLAGSTAFF        049/081 050/080 051/079      020 040 030 040 020 040
WINSLOW          060/092 061/092 062/091      020 010 010 010 020 030
PRESCOTT         060/087 061/087 062/086      020 030 020 030 020 030
PAGE             066/093 067/091 068/090      010 010 000 010 020 030
WINDOW ROCK      048/083 048/082 049/081      020 020 020 030 020 030
CANYON DE CHELLY 056/089 056/088 057/087      010 010 010 020 020 030
COTTONWOOD       068/101 068/100 070/099      020 030 020 030 020 030
GRAND CANYON     049/082 050/081 051/080      020 030 020 030 020 030
GREER            046/076 047/075 048/074      020 040 030 040 020 040
HEBER            051/086 052/085 053/084      020 040 030 040 020 040
JACOB LAKE       051/081 052/080 053/079      010 020 020 020 020 030
NAVAJO N.M.      053/082 054/081 055/081      020 010 010 020 020 030
PAYSON           060/092 061/091 062/090      010 030 030 030 020 030
SEDONA           065/096 066/095 067/094      010 040 030 030 020 040
SELIGMAN         056/090 057/089 058/088      010 030 030 020 020 030
SHOW LOW         057/086 057/085 058/084      020 040 030 030 020 040
ST. JOHNS        061/093 061/092 062/090      020 030 020 020 020 040
WUPATKI N.M.     061/094 062/094 063/093      020 020 010 020 020 030

Hazardous weather outlook, Sep 1, 9:35 AM MST, 7 hours 37 minutes before

AZZ004>018-037>040-020200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
935 AM MST MON SEP 1 2003

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

.DAY ONE...TODAY

SOUTHERLY FLOW ALOFT IS INCREASING THE MOISTURE OVER NORTHERN ARIZONA.
THE POTENTIAL FOR THUNDERSTORMS TODAY IS MAINLY OVER THE MOGOLLON RIM
...THE WHITE MOUNTAINS AND YAVAPAI COUNTY. LOOK FOR THE STORMS TO
DEVELOP BY LATE MORNING AND CONTINUE INTO EARLY THIS EVENING. A FEW
STORMS MAY PRODUCE HEAVY RAINS AND HAIL.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

MOISTURE WILL REMAIN OVER THE REGION THROUGH THE PERIOD. THUNDERSTORMS
ARE EXPECTED TO DEVELOP EACH DAY.

.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.

In the hours before

Local storm report, Sep 1, 2:02 PM MST, 3 hours 10 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
0202 PM MST MON SEP 01 2003

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

1145 AM    DONEY PARK                AZ   0.75 IN HAIL
09/01/03   COCONINO

1230 PM    10 NW FLAGSTAFF           AZ   1.00 IN HAIL
09/01/03   COCONINO

DF

Local storm report, Sep 1, 3:18 PM MST, 1 hour 54 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
0318 PM MST MON SEP 01 2003

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

0315 PM    SEDONA                    AZ   0.88 IN HAIL
09/01/03   YAVAPAI

DF

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 1, 5:55 PM MST	Flash Flood Warning	FGZ	Coconino	65 min

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; radar from the NEXRAD Level II archive.