Alert archive / Arizona / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 75, NWS Flagstaff, AZ

October 23, 2002Coconino County, Gila County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Oct 23, 2002, 10:10 AM MST for Coconino County, Gila County, Arizona. It was in force for 20 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
Oct 23, 2002, 10:10 AM MST (17:10 UTC)
Expired
Oct 23, 2002, 10:30 AM MST
In force
20 min
Issued by
NWS Flagstaff, AZ
Area
Counties, with a storm outline in the text

Counties Coconino County, AZ, Gila 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, 5.2 hours before the alert went out and 98 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, Flgstf/Belemont, AZ at 12:00Z on 2002-10-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 22 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Flgstf/Belemont, AZ at 12:00Z on 2002-10-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 92 square meters per square second.19395878Sfc1 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
22 J/kg
Mixed-layer CIN
-36 J/kg
Mixed-layer LCL
925 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
92 m²/s²
0-3 km storm-relative helicity
160 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 231710
SVRFGZ
AZC005-007-231730-

BULLETIN - EAS ACTIVIATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
1007 AM MST WED OCT 23 2002

THE NATIONAL WEATHER SERVICE IN FLAGSTAFF HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EXTREME NORTHWESTERN GILA COUNTY IN EAST CENTRAL ARIZONA
  SOUTHEASTERN COCONINO COUNTY IN NORTH CENTRAL ARIZONA

* UNTIL 1030 AM MST

* AT 959 AM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM OVER WASHINGTON PARK...OR ABOUT 7 MILES EAST OF
  PINE...MOVING NORTHEAST AT 20 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
RURAL SOUTHEASTERN COCONINO COUNTY AT 1020 AM 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 3442 11145 3429 11129 3453 11096 3469 11115

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 Oct 23, 9:05 AM MST, 1 hour 5 minutes earlier.

Area forecast discussion, Oct 23, 9:05 AM MST, 1 hour 5 minutes before
NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
905 AM MST WED OCT 23 2002

.SYNOPSIS...A SERIES OF WEATHER DISTURBANCES WILL MOVE ACROSS
NORTHERN ARIZONA OVER THE NEXT TWO DAYS. THESE WILL BRING SHOWERS
AND THUNDERSTORMS TO THE NORTHLAND TODAY THROUGH THURSDAY. ANOTHER
STRONGER SYSTEM IS EXPECTED TO MOVE INTO ARIZONA OVER THE WEEKEND
WITH COLDER TEMPERATURES...AND BETTER CHANCES FOR PRECIPITATION.
EXPECT LIGHT WINDS AND TEMPERATURES SLIGHTLY BELOW SEASONAL NORMALS
THROUGH THE BEGINNING OF NEXT WEEK.

.DISCUSSION...SCATTERED SHOWER AND THUNDERSTORM ACTIVITY ALREADY
WELL UNDERWAY ACROSS CENTRAL AND NORTHEASTERN ARIZONA THIS MORNING.
THIS IS BEING DRIVEN BY NUMEROUS FACTORS. FIRST AND FOREMOST IS THE
FACT THAT MUCH MORE MOISTURE IS PRESENT ACROSS THE SOUTHWEST THAN
THE MODELS WOULD LIKE TO ADMIT. SECOND...A WEAK TROUGH IS MOVING
THROUGH NORTHERN ARIZONA TODAY WITH MODERATELY UNSTABLE MID LEVEL
TEMPERATURES. LAST BUT NOT LEAST...A STRONG JET STREAK OVER NORTHERN
MEXICO AND FAR SOUTHEAST ARIZONA IS PROVIDING UPPER LEVEL DIV AND
SOME SHEAR TODAY. THE FOCUS OF THE MORE DYNAMICALLY DRIVEN ACTIVITY
WILL SHIFT EAST THROUGH THE DAY...BUT THE AIRMASS WILL STILL REMAIN
UNSTABLE ENOUGH FOR SCATTERED CONVECTION AS FAR WEST AS THE GRAND
CANYON. CURRENT ZONES HAVE POPS NEARLY EVERYWHERE...WILL MAKE MINOR
UPDATES TO ADJUST POPS FOR THE MORE ACTIVE AREAS...AND TO BETTER
REFLECT CURRENT ACTIVITY. WEAK S/WV RIDGING WILL QUIET THINGS DOWN
TONIGHT AHEAD OF ANOTHER MID LEVEL DISTURBANCE DUE THURSDAY. MORE ON
THIS IN THE AFTERNOON. PETERSON.

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        055/030 054/026 057/030      050 020 030 000 000 000
WINSLOW          068/038 066/033 072/037      040 020 040 000 000 000
PRESCOTT         066/039 065/035 069/039      030 000 030 000 000 000
PAGE             061/046 063/044 068/049      030 000 000 000 000 000
WINDOW ROCK      055/030 054/025 060/031      050 030 040 020 000 000
CANYON DE CHELLY 066/041 066/036 071/039      050 020 020 000 000 000
COTTONWOOD       076/046 075/042 079/046      030 000 030 000 000 000
GRAND CANYON     057/031 058/027 062/031      030 000 020 000 000 000
GREER            053/030 052/026 055/030      050 020 040 020 000 000
HEBER            062/032 060/028 063/033      050 020 040 010 000 000
JACOB LAKE       050/031 049/027 052/031      020 000 000 000 000 000
NAVAJO N.M.      057/037 056/032 063/038      050 020 020 000 000 000
PAYSON           069/039 067/035 073/040      030 000 040 000 000 000
SEDONA           074/047 071/043 078/047      040 000 030 000 000 000
SELIGMAN         068/034 067/032 071/034      020 000 030 000 000 000
SHOW LOW         054/035 054/032 068/038      050 020 040 020 000 000
ST. JOHNS        066/038 064/032 070/040      040 020 040 000 000 000
WUPATKI N.M.     069/043 067/038 073/042      040 020 030 000 000 000
Hazardous weather outlook, Oct 23, 7:00 AM MST, 3 hours 10 minutes before
AZZ004>018-037>040-240200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
700 AM MST WED OCT 23 2002

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

.DAY ONE...TODAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

A SLOW MOVING WEATHER SYSTEM WILL BRING ANOTHER DAY OF SCATTERED
SHOWERS AND WIDELY SCATTERED THUNDERSTORMS...MAINLY FROM THE
MOGOLLON RIM EAST TO THE NEW MEXICO BORDER. A FEW STRONG
THUNDERSTORM WILL BE POSSIBLE THIS AFTERNOON OVER PORTIONS OF THE
WHITE MOUNTAINS AND THE EASTERN MOGOLLON RIM. THE MAIN THREAT FROM
THESE STORMS WILL BE BRIEF HEAVY RAIN AND GUSTY WINDS.

.INSTRUCTIONS TO SPOTTERS...

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

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

ANOTHER IN A SERIES OF PACIFIC STORM SYSTEM WILL CROSS CENTRAL
SECTIONS OF THE STATE ON THURSDAY. THERE WILL BE A CHANCE OF SHOWERS
AND THUNDERSTORMS MAINLY FROM THE MOGOLLON RIM SOUTH. A STRONGER AND
COLDER SYSTEM WILL BEGIN TO AFFECT NORTHERN ARIZONA LATE FRIDAY AND
CONTINUE THROUGH SUNDAY.

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

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

Nearby

Severe Thunderstorm Warnings in Arizona, 2002Every 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.