Alert archive / Arizona / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 40, NWS Flagstaff, AZ

August 28, 2002Gila County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Aug 28, 2002, 7:39 PM MST for Gila County, Arizona. It was in force for 31 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: Aug 28, 2002, 7:39 PM MST (02:39 UTC)
Expired: Aug 28, 2002, 8:10 PM MST
In force: 31 min
Issued by: NWS Flagstaff, AZ
Area: Counties, with a storm outline in the text

County Gila County, AZ

The radar

The Flagstaff radar (KFSX), 58 km from the middle of the area, began a volume at 02:40 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, 2.7 hours before the alert went out and 93 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: 888 J/kg
Mixed-layer CIN: -14 J/kg
Mixed-layer LCL: 2880 m above ground
0-6 km bulk shear: 48 kt
0-1 km storm-relative helicity: 42 m²/s²
0-3 km storm-relative helicity: 104 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.6

Open this sounding in Storm Lab

The text

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

867 
WUUS55 KFGZ 290239
SVRFGZ
AZC007-290315-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
738 PM MST WED AUG 28 2002

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WEST CENTRAL GILA COUNTY IN EAST CENTRAL ARIZONA

* UNTIL 810 PM MST

* AT 738 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 7 MILES SOUTH OF JAKES CORNER...OR ABOUT 23
  MILES SOUTH OF PAYSON...MOVING NORTHEAST AT 30 MPH.

* THE SEVERE THUNDERSTORM WILL AFFECT OR PASS CLOSE TO...
  JAKES CORNER BY 750 PM MST

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

LAT...LON 3404 11143 3392 11125 3412 11113 3419 11132

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 Aug 28, 2:50 PM MST, 4 hours 49 minutes earlier.

Area forecast discussion, Aug 28, 2:50 PM MST, 4 hours 49 minutes before

NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
250 PM MST WED AUG 28 2002

.SYNOPSIS...MOISTURE WILL CONTINUE TO MOVE NORTHWARD INTO EASTERN
AND CENTRAL ARIZONA THROUGH THURSDAY. EXPECT SCATTERED SHOWERS AND
THUNDERSTORMS FROM FLAGSTAFF EASTWARD INTO THURSDAY EVENING...SOME
STORMS MAY BE QUITE STRONG. DRIER AIR WILL AGAIN MOVE IN FROM THE
WEST THURSDAY NIGHT...WITH ONLY PARTLY CLOUDY SKIES EXPECTED OVER
MOST OF THE AREA THROUGH THE LABOR DAY WEEKEND. MOISTURE WILL BE
SLOW TO LEAVE THE SOUTHERN PORTIONS OF THE FORECAST AREA...WITH A
CHANCE OF SHOWERS AND THUNDERSTORMS OVER THE EASTERN RIM AND WHITE
MOUNTAINS LASTING INTO NEXT WEEK.

.DISCUSSION...A BUSY DAY TODAY WILL LIKELY TURN INTO A BUSY NIGHT.
STRONG UPPER LEVEL DIV SIGNATURE OVER THE EAST CENTRAL ZONES WILL
CONTINUE INTO THIS EVENING...AND SHIFT SLIGHTLY FURTHER WEST AS THE
LAST S/WV ROTATES AROUND THE GREAT BASIN TROUGH. THIS COULD LEAD TO
A MCS TONIGHT...OR AT LEAST LONG-LIVED NOCTURNAL CONVECTION. EVENING
CONVECTION WILL ALSO PUSH THE MOISTURE FARTHER WEST OVERNIGHT...AT
LEAST UP TO FLAGSTAFF. THIS MOISTURE WILL ENABLE ANOTHER ACTIVE DAY
THURSDAY FROM FLG EASTWARD...BEFORE THE GREAT BASIN TROUGH LIFTS TO
THE NORTH AND FLOW TURNS MORE WESTERLY ACROSS THE NORTHERN HALF OF
THE STATE. THIS WILL PROGRESSIVELY DRY OUT MUCH OF THE AREA BY
THURSDAY NIGHT AND FRIDAY...WITH POPS HOLDING OUT THE LONGEST IN THE
WHITE MOUNTAINS. THE EXTENDED PERIOD FEATURES DRY WESTERLY FLOW
ACROSS THE NORTHERN ZONES AS HIGH PRESSURE CONTINUE TO SIT JUST
SOUTH OF AN OPTIMAL POSITION. THE CENTRAL AND SOUTHERN PORTIONS OF
THE STATE WILL REMAIN IN MARGINAL MOISTURE...SO WE WILL KEEP POPS IN
THE EXTENDED IN ZONES 16/17/18 ONLY. PETERSON.

.FGZ...NONE.

.CODED TEMPERATURES/POPS FOR SELECTED CITIES IN NORTHERN ARIZONA

CITY             TEMPERATURES LO/HI           PROBABILITY OF PRECIP
                 TON THU   FRI     SAT        TON THU   FRI     SAT
FLAGSTAFF        049/078 046/080 045/080      020 030 000 000 000 000
WINSLOW          062/089 059/089 057/089      020 020 020 000 000 000
PRESCOTT         060/087 057/090 056/090      020 000 000 000 000 000
PAGE             069/091 067/092 066/092      000 000 000 000 000 000
WINDOW ROCK      047/079 046/082 045/082      030 030 020 000 000 000
CANYON DE CHELLY 055/085 054/088 053/088      020 020 000 000 000 000
COTTONWOOD       068/098 065/101 064/101      020 000 000 000 000 000
GRAND CANYON     049/079 046/081 045/081      000 000 000 000 000 000
GREER            046/073 043/075 042/075      040 040 030 020 020 020
HEBER            051/083 048/085 047/085      030 030 020 000 000 000
JACOB LAKE       049/076 046/078 045/078      000 000 000 000 000 000
NAVAJO N.M.      052/079 051/082 050/082      020 020 000 000 000 000
PAYSON           061/091 058/094 057/094      030 030 020 000 000 000
SEDONA           066/095 063/098 062/098      020 000 000 000 000 000
SELIGMAN         053/090 050/093 049/093      000 000 000 000 000 000
SHOW LOW         057/083 054/085 053/085      030 030 030 020 020 020
ST. JOHNS        057/084 054/084 052/084      040 040 030 020 020 020
WUPATKI N.M.     063/091 060/091 058/091      020 020 000 000 000 000

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 28, 5:58 PM MST	Severe Thunderstorm Warning	FGZ	Gila	47 min
Aug 28, 6:53 PM MST	Severe Thunderstorm Warning	FGZ	Coconino, Gila	22 min
Aug 28, 7:10 PM MST	Severe Thunderstorm Warning	FGZ	Coconino, Gila	35 min

Nearby

Severe Thunderstorm Warnings in Arizona, 2002 Every severe thunderstorm warning in 2002

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.