Alert archive / Arizona / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 31, NWS Flagstaff, AZ

July 17, 2002Gila County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Jul 17, 2002, 5:28 PM MST for Gila County, Arizona. It was in force for 32 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 17, 2002, 5:28 PM MST (00:28 UTC)
Expired
Jul 17, 2002, 6:00 PM MST
In force
32 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 00:28 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, 0.5 hours before the alert went out and 120 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, Phoenix, AZ at 00:00Z on 2002-07-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 225 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Phoenix, AZ at 00:00Z on 2002-07-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 12 square meters per square second.1939Sfc1 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
225 J/kg
Mixed-layer CIN
-50 J/kg
Mixed-layer LCL
2523 m above ground
0-6 km bulk shear
6 kt
0-1 km storm-relative helicity
12 m²/s²
0-3 km storm-relative helicity
20 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.

538 
WUUS55 KFGZ 180028
SVRFGZ
AZC007-180100-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
527 PM MST WED JUL 17 2002

THE NATIONAL WEATHER SERVICE HAS ISSUED A

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

* UNTIL 600 PM MST

* AT 527 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM NEAR YOUNG...OR ABOUT 20 MILES SOUTHEAST OF
  KOHLS RANCH...MOVING NORTHWEST AT 5 MPH.

* THE SEVERE THUNDERSTORM WILL AFFECT OR PASS CLOSE TO...
RURAL NORTHERN GILA COUNTY AT 540 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 3397 11093 3409 11077 3430 11097 3415 11117

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 17, 2:30 PM MST, 2 hours 58 minutes earlier.

Area forecast discussion, Jul 17, 2:30 PM MST, 2 hours 58 minutes before
NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
230 PM MST WED JUL 17 2002

.SYNOPSIS...THE AIR MASS OVER NORTHERN ARIZONA WILL REMAIN VERY
MOIST THROUGH THE END OF THE WEEK AND INTO THE WEEKEND. SEASONAL
TEMPERATURES CAN BE EXPECTED WITH AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS EACH DAY.

.DISCUSSION...AZ BTWN WEAK TROF OFF CA COAST AND HIGH PRESSURE TO
THE EAST. DEFORMATION ZONE ACROSS THE STATE TODAY SEEMS TO BE THE
FOCUS OF CONVECTION. STORMS SO FAR HAVE BEEN WEAK AND PULSEY WITH
JUST LITE PRECIP AMOUNTS. TROF MOVES ON SHORE AND THRU THE GREAT
BASIN LATE THURSDAY THEN HIGH PRESSURE RIDGE REESTABLISHES ITSELF
OVER THE STATE. AIR MASS REMAINS VERY MOIST WITH PW AT AN INCH OR
MORE THRU THE WEEKEND. WILL KEEP STANDARD MONSOON FCST WITH
AFTERNOON/EVENING SHOWERS/TSTMS EACH DAY.

EXTENDED...MEDIUM RANGE MODELS ARE IN FAIR AGREEMENT TODAY. TYPICAL
MONSOON PATTERN PROGGED THRU THE PERIOD. MODELS HINTING AS A LITTLE
DRIER AIR MOVING IN FROM THE WEST. WESTERN SECTIONS MAY SEE A SLIGHT
DOWNTURN IN PRECIP WITH THE EASTERN HALF HAVING THE BEST CHANCES OF
PRECIP. WILL BROADBRUSH THE ENTIRE CWA FOR NOW AND WILL KEEP MENTION
OF DAILY SHOWERS AND TSTMS GOING. LITTLE CHANGE IN TEMPS EXPECTED. DF

.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        056/075 053/077 052/077      030 050 030 040 030 040
WINSLOW          065/087 064/088 063/088      020 030 020 030 020 030
PRESCOTT         062/085 061/086 060/086      030 040 030 030 020 020
PAGE             071/093 071/093 070/093      020 030 020 030 020 020
WINDOW ROCK      052/080 052/080 054/080      030 050 030 050 040 050
CANYON DE CHELLY 058/086 058/086 060/086      020 040 020 040 030 040
COTTONWOOD       070/096 069/097 068/097      020 030 020 020 020 020
GRAND CANYON     055/077 052/079 051/079      020 040 020 030 020 030
GREER            052/071 049/073 048/073      050 080 050 070 050 070
HEBER            057/080 054/082 053/082      040 070 040 060 040 060
JACOB LAKE       056/073 053/075 052/075      020 040 020 030 020 030
NAVAJO N.M.      056/080 056/080 058/080      020 040 020 040 030 040
PAYSON           063/090 062/091 061/091      030 020 030 030 020 020
SEDONA           068/094 067/095 066/095      020 030 020 020 020 020
SELIGMAN         055/088 054/089 053/089      020 030 020 020 010 010
SHOW LOW         064/081 061/083 060/083      030 050 030 040 030 040
ST. JOHNS        060/081 059/082 058/082      030 040 030 040 030 040
WUPATKI N.M.     068/089 067/090 066/090      020 030 020 030 020 030

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 17, 6:55 PM MSTFlash Flood WarningFGZNavajo2 hr
Jul 17, 6:58 PM MSTFlash Flood WarningFGZNavajo3 hr
Jul 17, 8:58 PM MSTFlash Flood WarningFGZGila, Navajo2 hr
Jul 17, 9:00 PM MSTFlash Flood WarningFGZGila, Navajo60 min
Jul 17, 11:03 PM MSTFlash Flood WarningFGZGila57 min
Jul 17, 11:06 PM MSTFlash Flood WarningFGZGila114 min

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; radar from the NEXRAD Level II archive.