Alert archive / Arizona / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 64, NWS Flagstaff, AZ

August 17, 1997Yavapai County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Aug 17, 1997, 3:34 PM MST for Yavapai County, Arizona. It was in force for 51 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 17, 1997, 3:34 PM MST (22:34 UTC)
Expired
Aug 17, 1997, 4:25 PM MST
In force
51 min
Issued by
NWS Flagstaff, AZ
Area
Whole counties

County Yavapai County, AZ

The radar

The Flagstaff radar (KFSX), 124 km from the middle of the area, began a volume at 22:38 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.

The nearest sounding before it

Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 10.6 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 1997-08-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 72 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 1997-08-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 57 square meters per square second.1939587897Sfc1 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
72 J/kg
Mixed-layer CIN
-61 J/kg
Mixed-layer LCL
1027 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
57 m²/s²
0-3 km storm-relative helicity
54 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 
TTAA00 KFLG 172235 RRA
SVRFLG
AZC025-172325-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
334 PM MST SUN AUG 17 1997

THE NATIONAL WEATHER SERVICE IN FLAGSTAFF AZ HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 425 PM MST
FOR PEOPLE IN THE FOLLOWING LOCATION...

IN CENTRAL ARIZONA

   ...NORTHEASTERN YAVAPAI COUNTY
 
AT 333 PM MST...A SEVERE THUNDERSTORM WAS INDICATED BY FLAGSTAFF
DOPPLER RADAR IN THE VICINITY OF COTTONWOOD MOVING NORTHEAST AT 10
MPH.

SOME LOCATIONS IN THE WARNING AREA INCLUDE...  COTTONWOOD AND
CLARKDALE.
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MPH...
DESTRUCTIVE HAIL...FREQUENT LIGHTNING...AND VERY HEAVY RAIN. FOR
YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF
YOUR HOME OR BUSINESS.

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 17, 2:02 PM MST, 1 hour 32 minutes earlier.

Area forecast discussion, Aug 17, 2:02 PM MST, 1 hour 32 minutes before
NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
200 PM MST SUN AUG 17 1997

PASSAGE OF A WEAK DISTURBANCE WHICH TRIGGERED EARLY MORNING
CONVECTION IN YAVAPAI COUNTY HAS PROVIDED A LATE START TO AFTERNOON
ACTIVITY IN WESTERN PORTIONS OF THE CWA. LATE MORNING START TO
ACTIVITY OVER THE DESERTS MAY HAVE ALSO BLOCKED OPTIMAL MOISTURE
ADVECTION INTO THIS REGION AS WELL. HOWEVER...KFSX 88D IMAGERY HAS
BEEN INDICATING A SLOW WESTWARD PROGRESSION OF THE SHOWERS AND
THUNDERSTORMS EARLY THIS AFTERNOON. SO...WILL HANG ON TO HIGH POPS
OVER THE CURRENTLY DRY WESTERN ZONES INTO TONIGHT. STILL CONCERNED
ABOUT PORTIONS OF NORTHWEST COCONINO COUNTY FOR A FLASH FLOOD WATCH
TONIGHT AS THE 12Z ETA AND AVN CONTINUE TO FORECAST A DECENT PV
ANOMALY THROUGH THE REGION BY 06Z. TIME SEEMS TO BE ON OUR SIDE HERE
SO WILL HOLD OFF. FLASH FLOOD WATCH CURRENTLY IN EFFECT LOOKING GOOD
FOR ZONE 18 AND HOLDING ON FOR ZONE 8 PER ABOVE. OTHERWISE...PLENTY
OF RESIDUAL MOISTURE ON MONDAY FOR ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS...BUT HAVE TONED DOWN WESTERN AREAS A BIT AS DYNAMICS
LACKING. MOISTURE FROM THE TROPICAL SYSTEM OFF BAJA PROGGED BY THE
MODELS TO MOVE INTO SOUTHERN CALIFORNIA ON TUESDAY...THOUGH THE AVN
BLEEDS SOME H5 MOISTURE ASSOCIATED WITH THIS SYSTEM INTO NORTHERN AZ.
ANY EASTWARD CHANGE IN TRAJECTORY WITH THIS SYSTEM COULD
SIGNIFICANTLY AFFECT THE GOING FORECAST OF SCATTERED SHOWERS AND
THUNDERSTORMS. OTHERWISE...TEMPS SHOULD WARM A BIT THROUGH THE PERIOD
AND FWC AND FAN GUIDANCE ARE IN THE BALLPARK.

FLG 6555  INW 4444

PASSETTI

FLG...NONE

Nearby

Severe Thunderstorm Warnings in Arizona, 1997Every severe thunderstorm warning in 1997

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.