Alert archive / Arizona / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 4, NWS Flagstaff, AZ

April 11, 1997Coconino County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Apr 11, 1997, 12:19 PM MST for Coconino County, Arizona. It was in force for 31 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
Apr 11, 1997, 12:19 PM MST (19:19 UTC)
Expired
Apr 11, 1997, 12:50 PM MST
In force
31 min
Issued by
NWS Flagstaff, AZ
Area
Whole counties

County Coconino County, AZ

The radar

The Flagstaff radar (KFSX), 150 km from the middle of the area, began a volume at 19:21 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, 7.3 hours before the alert went out and 68 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 1997-04-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 1997-04-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -6 square meters per square second.193958Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1584 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
-6 m²/s²
0-3 km storm-relative helicity
19 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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 Apr 11, 8:25 AM MST, 3 hours 54 minutes earlier.

Area forecast discussion, Apr 11, 8:25 AM MST, 3 hours 54 minutes before
NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
825 AM MST FRI APR 11 1997

ENHANCED CLOUDINESS ON RAMSDIS 4KM IR IMAGERY OVER THE WHITE
MOUNTAINS/FAR EASTERN LITTLE COLORADO RIVER VALLEY AT THIS TIME.
REPORTS FROM THE AREA INDICATE POCKETS OF HEAVY SNOW WITH
ACCUMULATIONS ON ROADS ABOVE 7500 FEET.  SNOWING DOWN AT ST. JOHNS AS
WELL.  THIS AREA LINES UP WELL WITH 12Z RUC AND ETA QPFS. EXPECT THIS
DISTURBANCE TO MOVE OUT BY LATE MORNING AND HAVE UPDATED FOR THIS
ALREADY.

12Z FGZ SOUNDING INDICATING AN INITIAL LI OF ZERO.  88D AND OBS
INDICATING ISOLATED SHOWERS OR VIRGA ABOUT THE REGION. NEXT VORT MAX
NEAR LAS PROGGED TO SWEEP THROUGH TODAY.  ETA LI FIELDS FOR 00Z SAT
LINES UP WELL WITH 94O GRAPHIC FROM SPC.  MOISTURE LOOKS
LIMITED...BUT WITH DYNAMICS ASSOCIATED WITH VORT...SHOULD BE ENOUGH
FOR ISOLATED SHOWERS.  MAYBE A BIT MORE COVERAGE NEEDED THAN
CURRENTLY ADVERTISED AND WILL EXAMINE THIS MORE WHEN REST OF 12Z DATA
COMES IN.

FLG 100  INW 000

PASSETTI

FLG...NONE.

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 11, 12:19 AM MSTSevere Thunderstorm WarningFGZCoconino31 min
Apr 11, 12:29 PM MSTSevere Thunderstorm WarningFGZCoconino21 min

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.