Alert archive / Arizona / Severe Thunderstorm Warnings in 2007

Severe Thunderstorm Warning 79, NWS Flagstaff, AZ

September 16, 2007Gila County, Navajo County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Sep 16, 2007, 3:02 PM MST for Gila County, Navajo County, Arizona. It was in force for 28 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 16, 2007, 3:02 PM MST (22:02 UTC)
Expired
Sep 16, 2007, 3:30 PM MST
In force
28 min
Issued by
NWS Flagstaff, AZ
Area
Counties, with a storm outline in the text

Counties Gila County, AZ, Navajo County, AZ

The radar

The Flagstaff radar (KFSX), 117 km from the middle of the area, began a volume at 22:02 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Sep 16, 11:38 AM MSTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Phoenix, AZ (KPSR), launched 12:00Z, 10.0 hours before the alert went out and 189 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 12:00Z on 2007-09-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 576 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 12:00Z on 2007-09-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -10 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
576 J/kg
Mixed-layer CIN
-184 J/kg
Mixed-layer LCL
1896 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
-10 m²/s²
0-3 km storm-relative helicity
31 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 162203
SVRFGZ
AZC007-017-162230-
/O.NEW.KFGZ.SV.W.0079.070916T2202Z-070916T2230Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
302 PM MST SUN SEP 16 2007

THE NATIONAL WEATHER SERVICE IN FLAGSTAFF HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EAST CENTRAL GILA COUNTY IN EAST CENTRAL ARIZONA...
  SOUTHEASTERN NAVAJO COUNTY IN NORTHEAST ARIZONA...

* UNTIL 330 PM MST

* AT 253 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING NICKEL SIZE HAIL.  THIS
  STORM WAS LOCATED 15 MILES SOUTHWEST OF PINETOP-LAKESIDE...OR ABOUT
  18 MILES SOUTH OF SHOW LOW...AND MOVING NORTHEAST AT 10 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  8 MILES SOUTHWEST OF PINETOP-LAKESIDE BY 330 PM MST...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 700 PM MST SUNDAY
EVENING FOR NORTHERN ARIZONA.

LAT...LON 3422 11005 3405 10987 3388 11013 3401 11028
TIME...MOT...LOC 2202Z 227DEG 9KT 3401 11012

$$

DJO
1 follow-up statement
000 
WWUS55 KFGZ 162227
SVSFGZ

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
326 PM MST SUN SEP 16 2007

AZC007-017-162236-
/O.EXP.KFGZ.SV.W.0079.000000T0000Z-070916T2230Z/
NAVAJO AZ-GILA AZ-
326 PM MST SUN SEP 16 2007

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL GILA AND
SOUTHEASTERN NAVAJO COUNTIES EXPIRES AT 330 PM MST...

THE SEVERE THUNDERSTORM PROMPTING THE WARNING HAS WEAKENED AND IS NO
LONGER SEVERE. HOWEVER...HEAVY RAIN...DANGEROUS LIGHTNING...AND SMALL
HAIL CONTINUE WITH THIS STORM LOCATED 10 MILES SOUTHWEST OF PINETOP
AT 325 PM MST.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 700 PM MST SUNDAY
EVENING FOR NORTHERN ARIZONA.

LAT...LON 3422 11005 3405 10987 3388 11013 3401 11028
TIME...MOT...LOC 2226Z 227DEG 9KT 3405 11007

$$

DJO

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 16, 2:09 PM MST, 53 minutes earlier.

Area forecast discussion, Sep 16, 2:09 PM MST, 53 minutes before
AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
200 PM SUN SEP 16 2007

.SYNOPSIS...EXPECT SHOWERS AND THUNDERSTORMS TO BECOME MORE NUMEROUS
TODAY AND MONDAY AS A LOW PRESSURE SYSTEM MOVES THROUGH THE GREAT
BASIN. ALONG WITH THE RAIN...EXPECT BREEZY TO LOCALLY WINDY
CONDITIONS...AND COOLER TEMPERATURES. DRIER AIR WILL MOVE INTO THE
STATE TUESDAY AND WEDNESDAY...WITH BREEZY CONDITIONS AND A CHANCE
FOR SHOWERS RETURNING LATER IN THE WEEK.

&&

.DISCUSSION...A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT THROUGH
7 PM MST FOR PORTIONS OF NORTHERN ARIZONA. SATELLITE AND RADAR DATA
INDICATE STORMS ARE BECOMING MORE NUMEROUS ACROSS THE REGION. EXPECT
THESE TO CONTINUE TO INTENSIFY DURING THE AFTERNOON WITH SOME STORMS
BECOMING SEVERE WITH STRONG DAMAGING WINDS...LARGE HAIL...AND HEAVY
RAIN.

A TROUGH WILL ENTER THE WESTERN REACHES OF THE GREAT BASIN LATER
TODAY...AND WILL MOVE ACROSS THE GREAT BASIN AND INTO WESTERN
COLORADO BY MONDAY EVENING. DIVQ FIELDS SHOW MODERATE DEEP-LAYER
UPWARD FORCING WILL MOVE ACROSS THE REGION OVERNIGHT AND EARLY
MONDAY IN ASSOCIATION WITH THIS TROUGH. 12 AND 18 UTC KFGZ SOUNDINGS
INDICATE THAT THE CAP HAS WEAKENED CONSIDERABLY...DEEP MOISTURE IS
IN PLACE...AND WINDS HAVE STRENGTHENED THROUGH A DEEP LAYER.

THUS...EXPECT A GOOD CHANCE OF CONVECTION TODAY...AND LASTING
THROUGH LATE MONDAY. RAIN COULD BE HEAVY AT TIMES TONIGHT AND EARLY
MONDAY AS THE DYNAMICAL PORTION OF THE TROUGH MOVES THROUGH.
TRAINING STORMS RESULTING IN EXCESS PCPN AMOUNTS COULD ALSO BE AN
ISSUE WITH LAYERED SOUTHWEST FLOW APPROACHING 40 KNOTS. IN
ADDITION...ENOUGH INSTABILITY AND DEEP LAYER SHEAR IS PRESENT FOR
SOME STORMS TO BECOME SEVERE WITH STRONG WINDS AND HAIL POSSIBLE.

MUCH DRIER AND MORE STABLE AIR FOLLOWS THIS TROUGH FOR CLEARING
CONDITIONS TUESDAY AND WEDNESDAY. ANOTHER STRONGER LOW WILL DROP
DOWN THE WEST COAST LATER IN THE WEEK...RESULTING IN BREEZY AND
COOLER  CONDITIONS ACROSS ARIZONA. THIS NEXT LOW MAY ALSO TAP
MOISTURE TO  OUR SOUTH...FOR A RENEWED CHANCE OF SHOWERS BY DAYS
FIVE  THROUGH SEVEN. MODELS CONTINUE TO EXHIBIT LARGE RUN-TO-RUN
VARIABILITY IN THE TIMING AND TRACK OF THIS SYSTEM. FOR NOW...HAVE
SOME LOW CHANCES OF SHOWERS AND THUNDERSTORMS.  DB

&&

.AVIATION...FOR THE 00Z PACKAGE...EXPECT SCT-BKN CLOUD COVER AT
11-14 KFT MSL WITH A CHANCE FOR SCT TO NUMEROUS TSRA AND SHRA.
FLIGHT CONDITIONS WILL BE PRIMARILY VFR WITH OCCASIONAL MVFR IN THE
STRONGEST STORMS. OTHER THAN THUNDERSTORMS THE STRONG BREEZY WINDS
WILL BE THE PRIMARY THREAT TO AVIATION THIS AFTERNOON AND EVENING
WITH SOUTHWEST  WIND SPEEDS AROUND 10-20 KTS AND GUSTS AROUND 35
KTS. WINDS WILL BE  ERRATIC AND GUSTY NEAR THUNDERSTORMS. SHOWER AND
THUNDERSTORM  CHANCES WILL CONTINUE THROUGH THE EVENING HOURS.
AVIATION DISCUSSION  NOT UPDATED FOR AMENDMENTS.  RB
&&

.FGZ WATCHES/WARNINGS/ADVISORIES...SVR THUNDERSTORM WATCH 670 IN
EFFECT THROUGH 7 PM MST FOR ZONES 004>010-012-013-015-016-037>040.

&&
Hazardous weather outlook, Sep 16, 11:45 AM MST, 3 hours 17 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
1145 AM MST SUN SEP 16 2007

AZZ004>018-037>040-170700-
WESTERN MOGOLLON RIM-GRAND CANYON COUNTRY-YAVAPAI COUNTY MOUNTAINS-
YAVAPAI COUNTY VALLEYS AND BASINS-OAK CREEK AND SYCAMORE CANYONS-
MARBLE AND GLEN CANYONS-KAIBAB PLATEAU-COCONINO PLATEAU-
NORTHEAST PLATEAU AND MESAS HWY 264 NORTHWARD-
NORTHEAST PLATEAU AND MESAS SOUTH OF HWY 264-
CHINLE VALLEY-CHUSKA MOUNTAINS AND DEFIANCE PLATEAU-
BLACK MESA AREA-LITTLE COLORADO RIVER VALLEY IN COCONINO COUNTY-
LITTLE COLORADO RIVER VALLEY IN NAVAJO COUNTY-
LITTLE COLORADO RIVER VALLEY IN APACHE COUNTY-
EASTERN MOGOLLON RIM-WHITE MOUNTAINS-NORTHERN GILA COUNTY-
1145 AM MST SUN SEP 16 2007

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

.DAY ONE...TODAY

A TROUGH OF LOW PRESSURE WILL INTERACT WITH DEEP MOISTURE FROM
MEXICO TODAY...CAUSING AN OUTBREAK OF POTENTIALLY SEVERE WEATHER.
EXPECT SHOWERS AND THUNDERSTORMS TO DEVELOP RAPIDLY AFTER 9 AM MST
THIS MORNING...BECOMING MORE FREQUENT AND WIDESPREAD BY THE
AFTERNOON.

THE STRONGEST AND MOST FREQUENT STORMS WILL BE OVER CENTRAL AND
WESTERN PORTIONS OF THE FORECAST AREA...INCLUDING MUCH OF YAVAPAI
AND COCONINO COUNTIES. THE STRONGER STORMS IN THESE AREAS WILL BE
CAPABLE OF PRODUCING TORRENTIAL RAINS AND LARGE HAIL...AS WELL AS
DAMAGING WINDS. A SEVERE THUNDERSTORM WATCH IS IN EFFECT UNTIL 7 PM
MST.

THERE WILL BE A MODEST THREAT OF FLOODING TODAY DUE TO THE STORMS
REDEVELOPING AND AFFECTING THE SAME AREAS MULTIPLE TIMES THROUGH THE
AFTERNOON.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

THE SAME LOW PRESSURE SYSTEM WILL CAUSE STRONG STORMS TO CONTINUE
OVERNIGHT AND INTO MONDAY. THE BEST AREA FOR THUNDERSTORMS WILL
SHIFT SLOWLY EAST TO THE NEW MEXICO BORDER BY MONDAY AFTERNOON.

.SPOTTER INFORMATION STATEMENT...

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

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 16, 2:17 PM MSTSevere Thunderstorm WarningFGZCoconino, Yavapai28 min

Nearby

Severe Thunderstorm Warnings in Arizona, 2007Every severe thunderstorm warning in 2007

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.