Alert archive / Arizona / Severe Thunderstorm Warnings in 2000

Severe Thunderstorm Warning 12, NWS Flagstaff, AZ

July 23, 2000Yavapai County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Jul 23, 2000, 1:00 PM MST for Yavapai County, Arizona. It was in force for 30 min. 1 report came from inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties, with what was reported inside it.

The facts

Issued: Jul 23, 2000, 1:00 PM MST (20:00 UTC)
Expired: Jul 23, 2000, 1:30 PM MST
In force: 30 min
Issued by: NWS Flagstaff, AZ
Area: Whole counties; the outline is the Mesonet’s reconstruction

County Yavapai County, AZ

The radar

The Flagstaff radar (KFSX), 111 km from the middle of the area, began a volume at 20:02 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.

What was reported inside it

Time	Report	Where	Remark
Jul 23, 1:10 PM MST	Hail 0.88	Prescott, AZ	Public report of nickel sized hail.

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The nearest sounding before it

Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 8.0 hours before the alert went out and 88 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: 22 J/kg
Mixed-layer CIN: -280 J/kg
Mixed-layer LCL: 2267 m above ground
0-6 km bulk shear: 3 kt
0-1 km storm-relative helicity: -37 m²/s²
0-3 km storm-relative helicity: 30 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 232003
SVRFLG
AZC025-232030-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
100 PM MST SUN JUL 23 2000

THE NATIONAL WEATHER SERVICE IN FLAGSTAFF HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL YAVAPAI COUNTY IN ARIZONA
  THIS INCLUDES THE CITIES OF...PRESCOTT

* UNTIL 130 PM MST

* SHORTLY BEFORE 100 PM MST...WEATHER SPOTTERS REPORTED A SEVERE     
  THUNDERSTORM OVER SOUTHERN PORTIONS OF THE CITY OF PRESCOTT.       
  THIS STORM WAS MOVING SLOWLY TO THE SOUTH AT AROUND 5 MPH.

HAIL UP TO ONE INCH IN DIAMETER HAS BEEN REPORTED WITH THIS STORM. 
IF YOU ARE IN THE PATH OF THE STORM...PUT YOUR CAR IN A GARAGE AND 
MOVE TO A SUBSTANTIAL SHELTER.


LAT...LON 3456 11260 3443 11244 3468 11210 3484 11230

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 23, 9:15 AM MST, 3 hours 45 minutes earlier.

Area forecast discussion, Jul 23, 9:15 AM MST, 3 hours 45 minutes before

NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
915 AM MST SUN JUL 23 2000

SYNOPSIS...MONSOON MOISTURE WILL REMAIN OVER PORTIONS OF NORTHERN
ARIZONA INTO THE MIDDLE OF THE COMING WEEK. FOR TODAY...AFTERNOON
AND EVENING SHOWERS AND THUNDERSTORMS WILL CONTINUE FROM THE
MOGOLLON RIM AND WHITE MOUNTAINS SOUTHWARD. ON MONDAY AND TUESDAY
MONSOON MOISTURE WILL SLOWLY SPREAD TO THE NORTHEAST PORTION OF THE
STATE WITH AN INCREASING CHANCE OF AFTERNOON THUNDERSTORMS OVER THE
LITTLE COLORADO RIVER VALLEY AND THE NAVAJO NATION. TEMPERATURES
WILL REMAIN ABOVE NORMAL.

DISCUSSION...NOT TOO MUCH CHANGE IN WX PATTERN FROM PRVS 24 HOURS.
EXCEPT WE HAVE A BIT MORE MOISTURE OVER THE CWA...AND THE MID LEVEL
CAP NO LONGER EVIDENT ON 12Z FGZ SOUNDING. ONCE SURFACE HEATING
KICKS IN...IT SHOULD BE EASY FOR CONVECTION TO FIRE OFF ONCE AGAIN
TODAY. THINK THREAT OF DOWNBURST WINDS HAS SLACKENED A LITTLE DUE TO
ADDITIONAL MOISTURE AT THE LOWER LEVELS FROM PRVS 24 HRS. WIND
PROFILE QUITE WEAK OVER THE CWA...AND MID LEVEL SOUTHERLY FLOW
WHICH FED YSTDYS STORMS NO LONGER EVIDENT...AS THESE WINDS HAVE
BECOME MORE SERLY. WEAK SHEAR PROFILE SHOULD LEAD TO FAIRLY SLOW
MOVING STORMS. 12Z MODELS INDICATED RATHER BROAD AREA OF CONVECTIVE
INSTABILITY OVER CWA TODAY...AS MAIN ANTICYCLONE SHIFT SLOWLY TO
THE WEST THIS EVENING. THIS COULD LEAVE TO WELL ORGANIZED CONVECTION
LATER THIS AFTERNOON. SOMETHING TO KEEP AN EYE ON....
PLAN NO UPDATES. MCGRATH

.FGZ...NONE.

In the hours before

Special weather statement, Jul 23, 9:30 AM MST, 3 hours 30 minutes before

AZZ004>018-037>040-232030-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
930 AM MST SUN JUL 23 2000

...SCATTERED THUNDERSTORMS ALONG AND SOUTH OF THE MOGOLLON RIM
TODAY...ISOLATED THUNDERSTORMS ACROSS THE COCONINO PLATEAU AND
LITTLE COLORADO RIVER VALLEY...

SPOTTER REPORTS OF HEAVY RAIN AND HAIL REQUESTED.

MONSOON MOISTURE REMAINS OVER NORTHERN ARIZONA TODAY...MAINLY SOUTH
OF THE INTERSTATE 40 CORRIDOR FROM SELIGMAN TO CHAMBERS IN EASTERN
ARIZONA. DAYTIME HEATING SHOULD KICK OFF ANOTHER ROUND OF SHOWERS
AND THUNDERSTORMS OVER THE HIGHER TERRAIN OF NORTHERN ARIZONA BY
AROUND 1 PM MST...WHICH WILL SPREAD INTO MOST VALLEY LOCATIONS OF
YAVAPAI COUNTY AND THE LITTLE COLORADO RIVER VALLEY LATER THIS
AFTERNOON.

THE MAIN THREATS TODAY FROM THE THUNDERSTORMS WILL BE HEAVY
RAIN...HAIL ALONG WITH FREQUENT LIGHTNING. SOME STORMS MAY ALSO
CONTAIN STRONG GUSTY WINDS...ESPECIALLY DURING THE MID TO LATE
AFTERNOON HOURS.

THE HAZARDOUS WEATHER OUTLOOK GIVES PRELIMINARY INFORMATION FOR THE
POSSIBILITY OF WEATHER THAT COULD BECOME SEVERE...DAMAGING WINDS IN
EXCESS OF 57 MPH...HAIL 3/4 INCH IN DIAMETER OR LARGER...AND HEAVY
RAINFALL THAT COULD CAUSE FLOODING OR RUNNING WASHES. WHEN
HAZARDOUS WEATHER BEGINS...IMPORTANT LIFE SAVING INFORMATION WILL BE
PROVIDED IN SHORT TERM FORECASTS...SEVERE WEATHER AND FLOOD WARNINGS
...AND FOLLjOW-UP STATEMENTS.
MCGRATH

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 23, 12:28 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	32 min
Jul 23, 1:30 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	30 min
Jul 23, 2:12 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	33 min
Jul 23, 3:19 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	26 min
Jul 23, 4:28 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	32 min

Nearby

Severe Thunderstorm Warnings in Arizona, 2000 Every severe thunderstorm warning in 2000

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.