Alert archive / Arizona / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 36, NWS Flagstaff, AZ

August 28, 2002Apache County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Aug 28, 2002, 1:42 PM MST for Apache County, Arizona. It was in force for 33 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, 1:42 PM MST (20:42 UTC)
Expired: Aug 28, 2002, 2:15 PM MST
In force: 33 min
Issued by: NWS Flagstaff, AZ
Area: Counties, with a storm outline in the text

County Apache County, AZ

The radar

The Flagstaff radar (KFSX), 158 km from the middle of the area, began a volume at 20:44 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 12:00Z, 8.7 hours before the alert went out and 235 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 3615 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 64 m²/s²
0-3 km storm-relative helicity: 119 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.

599 
WUUS55 KFGZ 282042
SVRFGZ
AZC001-282115-

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

THE NATIONAL WEATHER SERVICE HAS EXTENDED THE

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTH CENTRAL APACHE COUNTY IN NORTHEAST ARIZONA

* UNTIL 215 PM MST

* AT 139 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 31 MILES SOUTHWEST OF LYMAN LAKE STATE PARK...
  OR ABOUT 12 MILES WEST OF GREER...MOVING NORTHEAST AT 30 MPH.

* THE SEVERE THUNDERSTORM WILL AFFECT OR PASS CLOSE TO...
  STATE ROUTE 260 AT 145 PM MST
  5 MILES SOUTH OF LYMAN LAKE STATE PARK AT 215 PM MST

VERY LARGE HAIL IS POSSIBLE WITH THIS SEVERE THUNDERSTORM. IF YOU ARE
IN THE PATH OF THE STORM...PUT YOUR CAR IN A GARAGE 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.

LAT...LON 3401 10976 3391 10957 3428 10926 3440 10949

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, 9:15 AM MST, 4 hours 27 minutes earlier.

Area forecast discussion, Aug 28, 9:15 AM MST, 4 hours 27 minutes before

NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
915 AM MST WED AUG 28 2002

.SYNOPSIS...LOW PRESSURE OVER THE NORTHERN GREAT BASIN ALONG WITH
HIGH PRESSURE OVER NEW MEXICO WILL PRODUCE GUSTY SOUTHWEST WINDS
OVER NORTHERN ARIZONA TODAY. SOME MOISTURE FROM MEXICO WILL ALSO BE
DRAWN NORTHEASTWARD...RESULTING IN ISOLATED THUNDERSTORMS FROM
FLAGSTAFF EASTWARD TODAY. LOCALLY BREEZY CONDITIONS WEST AND CENTRAL
PORTIONS AND A CHANCE OF THUNDERSTORMS IN THE EAST WILL CONTINUE
INTO THE WEEKEND.

.DISCUSSION...MAIN CONCERN TODAY WILL BE WINDS. NRN AZ REMAINS
BETWEEN TROF OVER NORTHERN GREAT BASIN AND HIGH PRESSURE TO THE EAST
OF THE STATE. NO FGZ SOUNDING BUT PHX SOUNDING INDICATES 30-40 KT OF
WIND ALOFT FOR GUSTY WINDS TODAY. REMAINING MIXED LAYER FROM
YESTERDAY WILL ALLOW US TO MIX RAPIDLY INTO THIS WIND FIELD FOR
EARLY START TO WINDS. STRONGEST WINDS ARE EXPECTED OVER THE WESTERN
HALF OF THE CWA AND LCR. THIS EVENT LOOKS AS THOUGH RED FLAG
CRITERIA WILL BE MET...BUT NOT LIKELY TO MEET PUBLIC WIND ADVISORY
CRITERIA. TROF FILLS ON THURSDAY AND GRADIENTS RELAX FOR LIGHTER
WINDS.

OTHER STORY WILL BE THE INFUSION OF MOISTURE THAT HAS MOVED INTO
MOST OF THE FORECAST AREA OVERNIGHT DUE TO MCS OVER NORTHERN MEXICO.
DEW POINTS UP 10 DEGREES OR MORE IN THE EAST AND TUS SOUNDING HAS
MORE THAN DOUBLED IN PRECIPITABLE WATER WITH AMPLE CONVECTIVE ENERGY
IN THE SOUNDING. SHOWERS HAVE STARTED ALREADY OVER THE WHITES SO
WILL BRING POPS UP OVER THIS REGION FOR TODAY. EXPECT ANOTHER MCS TO
DEVELOP LATER THIS AFTERNOON AND STEERING FLOW PUSHES THIS MOISTURE
NORTHEASTWARD OVER THE WHITES OVERNIGHT FOR CONTINUED CHANCE OF
THUNDERSTORMS.  STAUDENMAIER

.FGZ...NONE.

.CODED TEMPERATURES/POPS FOR SELECTED CITIES IN NORTHERN ARIZONA

CITY             TEMPERATURES HI/LO           PROBABILITY OF PRECIP
                 TDY TON   THU     FRI        TDY TON   THU   FRI
FLAGSTAFF        080/042 077/043 076/045      020 020 010 010 000 000
WINSLOW          092/056 088/057 087/059      000 000 020 020 000 000
PRESCOTT         088/058 087/057 086/059      000 000 000 000 000 000
PAGE             093/066 090/065 088/067      000 000 000 000 000 000
WINDOW ROCK      085/048 080/048 079/050      020 020 030 030 020 020
CANYON DE CHELLY 091/056 086/056 085/058      020 020 020 020 020 020
COTTONWOOD       099/066 098/065 097/067      000 000 000 000 000 000
GRAND CANYON     081/037 078/039 079/045      020 020 010 010 000 000
GREER            075/039 072/040 071/042      030 030 020 020 010 010
HEBER            085/044 082/045 081/047      030 030 020 020 010 010
JACOB LAKE       078/042 075/043 074/045      020 020 010 010 000 000
NAVAJO N.M.      085/053 080/053 079/055      020 020 020 020 020 020
PAYSON           092/059 091/058 090/060      000 000 000 000 000 000
SEDONA           096/064 095/063 094/065      000 000 000 000 000 000
SELIGMAN         091/051 090/050 089/052      000 000 000 000 000 000
SHOW LOW         085/050 082/051 081/053      020 020 020 020 010 010
ST. JOHNS        087/051 083/052 082/054      000 000 020 020 000 000
WUPATKI N.M.     094/057 090/058 089/060      000 000 020 020 000 000

In the hours before

Special weather statement, Aug 28, 9:30 AM MST, 4 hours 12 minutes before

AZZ004>018-037>040-281930-
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
930 AM MST WED AUG 28 2002

...A CHANCE OF SHOWERS AND THUNDERSTORMS RETURNS TO EAST CENTRAL
ARIZONA...

DISCUSSION...MOISTURE FROM NORTHERN MEXICO HAS MOVED OVER THE
SOUTHEAST AND EAST CENTRAL PORTIONS OF THE FORECAST AREA. SURFACE
DEWPOINTS HAVE RISEN MORE THAN TEN DEGREES...AND MID-LEVEL
TRAJECTORIES WILL ALLOW MORE MOISTURE TO MOVE OVER THIS REGION.
EXPECT SHOWERS AND THUNDERSTORMS TO DEVELOP OVER MAINLY THE WHITES
AND EASTERN MOGOLLON RIM DURING THE MORNING HOURS AND MOVE RAPIDLY
TO THE NORTHEAST. THEREFORE HEAVY RAINFALL IS NOT EXPECTED...BUT
BRIEF GUSTY WINDS MAY ACCOMPANY SOME OF THESE THUNDERSTORMS
...ESPECIALLY THIS AFTERNOON.

BURNED AREA RAIN OUTLOOK...

RODEO-CHEDISKI BURN AREA...EXPECT SCATTERED THUNDERSTORMS TO DEVELOP
AND MOVE RAPIDLY NORTHEASTWARD OVER THE BURN AREA. SOME BRIEF HEAVY
RAIN MAY ACCOMPANY SOME OF THE STRONGER STORMS WITH LOCAL RAINFALL
AMOUNTS OF UP TO A HALF INCH.

INDIAN BURN AREA...NO THUNDERSTORMS EXPECTED TODAY.

STAUDENMAIER

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 28, 11:21 AM MST	Severe Thunderstorm Warning	FGZ	Apache	24 min
Aug 28, 11:34 AM MST	Severe Thunderstorm Warning	FGZ	Apache	26 min
Aug 28, 1:04 PM MST	Severe Thunderstorm Warning	FGZ	Apache, Navajo	36 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.