Alert archive / Arizona / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 55, NWS Flagstaff, AZ

August 9, 2001Coconino County, Gila County, Yavapai County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Aug 9, 2001, 5:11 PM MST for Coconino County, Gila County, Yavapai County, Arizona. It was in force for 34 min. No storm report in the archive falls 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.

The facts

Issued
Aug 9, 2001, 5:11 PM MST (00:11 UTC)
Expired
Aug 9, 2001, 5:45 PM MST
In force
34 min
Issued by
NWS Flagstaff, AZ
Area
Whole counties; the outline is the Mesonet’s reconstruction

Counties Coconino County, AZ, Gila County, AZ, Yavapai County, AZ

The nearest sounding before it

Flgstf/Belemont, AZ (KFGZ), launched 00:00Z, 0.2 hours before the alert went out and 91 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 00:00Z on 2001-08-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 965 joules per kilogram.LCLEL10008507005003002001001 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 00:00Z on 2001-08-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 125 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
965 J/kg
Mixed-layer CIN
-8 J/kg
Mixed-layer LCL
1265 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
125 m²/s²
0-3 km storm-relative helicity
182 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.6

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

404 
WUUS55 KFGZ 100012
SVRFLG
AZC005-007-025-100045-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
511 PM MST THU AUG 9 2001

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EXTREME SOUTH CENTRAL COCONINO COUNTY IN ARIZONA
  EXTREME NORTHWESTERN GILA COUNTY IN ARIZONA
  THIS INCLUDES THE CITIES OF...STRAWBERRY...PINE
  EXTREME EAST CENTRAL YAVAPAI COUNTY IN ARIZONA

* UNTIL 545 PM MST

* AT 511 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 10 MILES WEST OF STRAWBERRY...MOVING EAST AT 15
  MPH.

* THE SEVERE THUNDERSTORM WILL AFFECT OR PASS CLOSE TO...
  OVER STRAWBERRY AT 535 PM MST
  OVER PINE 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.

HEAVY RAINS MAY FLOOD LOW LYING AREAS SUCH AS WASHES AND UNDERPASSES.
AVOID THESE AREAS AND DO NOT CROSS FLOODED ROADS AS THEY MAY BE
WASHED OUT. WATER LEVELS OF SMALL STREAMS AND RIVERS MAY ALSO RISE...
THEREFORE SEEK HIGHER GROUND IF THREATENED BY FLOOD WATERS.

REPORT SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY. THEY
WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST
OFFICE.

LAT...LON 3451 11170 3438 11175 3427 11149 3446 11142

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 9, 3:34 PM MST, 1 hour 37 minutes earlier.

Area forecast discussion, Aug 9, 3:34 PM MST, 1 hour 37 minutes before
NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
230 PM MST THU AUG 09 2001

.SYNOPSIS...LOW PRESSURE OVER NEW MEXICO WILL CONTINUE TO BRING
SHOWERS AND THUNDERSTORMS TO MUCH OF NORTHERN ARIZONA TONIGHT. THE
LOW PRESSURE SYSTEM WILL BEGIN TO WEAKEN ON FRIDAY WITH HIGH
PRESSURE STRENGTHENING OVER SOUTHERN CALIFORNIA. THIS WILL ALLOW A
DRIER AND WARMER NORTHWEST FLOW TO DEVELOP ON FRIDAY AND SATURDAY. HIGH
PRESSURE WILL GRADUALLY SHIFT TO THE FOUR CORNERS AREA BY EARLY NEXT
WEEK WITH ENOUGH MOISTURE FOR A CONTINUING CHANCE OF SHOWERS AND
THUNDERSTORMS.

.DISCUSSION...A MID TO UPPER TROUGH REMAINS OVER NEW MEXICO WITH AN
AN UPPER RIDGE CENTERED OVER NORTHERN BAJA CALIFORNIA. AS A
RESULT...A MOIST AND UNSTABLE NORTHEAST FLOW WILL CONTINUE FOR THE
NEXT 12- TO 24-HOURS. THERE WERE A FEW STRONG AND ORGANIZED
THUNDERSTORMS THIS AFTERNOON BUT MUCH OF THE AIR MASS ACROSS ARIZONA
REMAINED UNSTABLE AND UNTAPPED. FOR TONIGHT...WITH A LARGE AREA OF
THUNDERSTORMS DEVELOPING IN SOUTHERN UTAH AND FAR NORTHWEST ARIZONA
THIS AFTERNOON...EXPECT THIS AREA OF STORMS AND ASSOCIATED OUTFLOW
TO MOVE SOUTH AND SOUTHEASTWARD INTO COUNTY WARNING AREA TONIGHT FOR
PRETTY GOOD COVERAGE OF SHOWERS AND STORMS. ISOLATED SHOWERS AND STORMS
OVER THE NORTHEAST CORNER OF THE STATE. ON FRIDAY AND
SATURDAY...MODELS ARE INSISTING THAT THE UPPER RIDGE WILL SHIFT
NORTHWARD WITH A DRIER NORTH TO NORTHWEST FLOW DEVELOPING. THINK THE
NET RESULT WILL BE A DOWNTURN IN ACTIVITY INTO SATURDAY WITH A MORE
DIURNAL NATURE TO THUNDERSTORMS. PROBABLY STILL GO WITH A GENERAL
LOW END SCATTERED WORDING FOR FRIDAY AND SATURDAY OVER THE HIGHER
TERRAIN AND SOUTH AND SOUTHWEST OF THE RIM WITH ISOLATED STORMS
ELSEWHERE AS LOW-LEVEL MOISTURE WILL BE SLOW TO SCOUR OUT.

IN THE EXTENDED...EXTENDED MODELS ARE CONSISTENT IN KEEPING THE
SUBTROPICAL RIDGE AXIS LOCATED OVER THE SOUTHWEST UNITED STATES
THROUGH WELL INTO NEXT WEEK. IN ADDITION...NORTHWEST MEXICO WILL BE
IN A FAVORED LOCATION FOR THE DEVELOPMENT OF MESOSCALE CONVECTIVE
COMPLEXES WHICH SHOULD FAVOR A CONTINUED NORTHWARD PUSH OF MOISTURE
INTO ARIZONA. DAY TO DAY VARIATIONS IN THE LOCATION OF THE MID-LEVEL
CENTER OF ANTICYCLONIC CIRCULATION WILL MODULATE STORM ACTIVITY.
WILL LET THE STANDARD MONSOON FORECAST STAND THROUGH THE
EXTENDED.

MCCOLLUM

.FGZ...NONE.

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 9, 10:26 PM MSTFlash Flood WarningFGZCoconino2 hr
Aug 10, 11:12 AM MSTSevere Thunderstorm WarningFGZCoconino33 min
Aug 10, 1:34 PM MSTSevere Thunderstorm WarningFGZGila36 min

Nearby

Severe Thunderstorm Warnings in Arizona, 2001Every severe thunderstorm warning in 2001

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.