Alert archive / Arizona / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 59, NWS Flagstaff, AZ

August 10, 2001Gila County, Yavapai County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Aug 10, 2001, 8:18 PM MST for Gila County, Yavapai County, Arizona. It was in force for 32 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 10, 2001, 8:18 PM MST (03:18 UTC)
Expired
Aug 10, 2001, 8:50 PM MST
In force
32 min
Issued by
NWS Flagstaff, AZ
Area
Whole counties; the outline is the Mesonet’s reconstruction

Counties Gila County, AZ, Yavapai County, AZ

The radar

The Flagstaff radar (KFSX), 61 km from the middle of the area, began a volume at 03:16 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 00:00Z, 3.3 hours before the alert went out and 116 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 2001-08-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 330 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 00:00Z on 2001-08-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 56 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
330 J/kg
Mixed-layer CIN
-34 J/kg
Mixed-layer LCL
1649 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
56 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.

634 
WUUS55 KFGZ 110319
SVRFLG
AZC007-025-110350-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
818 PM MST FRI AUG 10 2001

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EXTREME NORTHWESTERN GILA COUNTY IN ARIZONA
  EXTREME SOUTHEASTERN YAVAPAI COUNTY IN ARIZONA

* UNTIL 850 PM MST

* AT 816 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM OVER EXTREME NORTHWESTERN GILA COUNTY...OR
  ABOUT 14 MILES SOUTHWEST OF STRAWBERRY...MOVING SOUTH-SOUTHWEST 
  AT 20 MPH.

* THE SEVERE THUNDERSTORM WILL AFFECT OR PASS CLOSE TO...
  RURAL NORTHWEST GILA COUNTY  
  2 MILES NORTH OF HORSESHOE RESERVOIR AT 840 PM MST
 
HAIL TO THE SIZE OF DIMES...INTENSE RAIN AND STRONG DAMAGING WINDS
ARE LIKELY WITH THIS STORM. TAKE COVER IN A SUBSTANTIAL SHELTER 
UNTIL THE STORM PASSES.

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

LAT...LON 3427 11155 3434 11175 3409 11188 3401 11166
$$
JJ

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 10, 2:30 PM MST, 5 hours 48 minutes earlier.

Area forecast discussion, Aug 10, 2:30 PM MST, 5 hours 48 minutes before
NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
230 PM MST FRI AUG 10 2001

.SYNOPSIS...A MOIST NORTHERLY FLOW WILL CONTINUE TO PRODUCE SHOWERS
AND THUNDERSTORMS OVER NORTHERN ARIZONA TONIGHT. THE LOW PRESSURE
SYSTEM OVER NEW MEXICO WILL DISSIPATE OVERNIGHT WITH HIGH PRESSURE
BUILDING OVER SOUTHERN CALIFORNIA AND WESTERN ARIZONA. THIS WILL ALLOW A
SOMEWHAT DRIER AND WARMER NORTHWEST FLOW TO DEVELOP ON 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...UPPER TROUGH OVER NEW MEXICO WILL ESSENTIALLY
DISSIPATE OVERNIGHT WITH THE UPPER RIDGE OVER SOUTHERN CALIFORNIA
BEGINNING TO DOMINATE THE FLOW PATTERN. THE RIDGE WILL GRADUALLY
SHIFT TO THE FOUR CORNERS AREA BY SUNDAY. IN ANY CASE...A GENERAL
NORTHERLY FLOW SHOULD REMAIN THROUGH SATURDAY WITH TRAJECTORIES A
LITTLE MORE NORTHWESTERLY. THIS WILL RESULT IN SOME DRYING OVER THE
NORTHERN PORTIONS OF THE COUNTY WARNING AREA (CWA) ON SATURDAY.
HOWEVER...MOISTURE WILL REMAIN AMPLE OVER SOUTHERN PORTIONS OF THE CWA.
BY SUNDAY...AS RIDGE SHIFTS TO THE FOUR CORNERS...THE FLOW WILL TURN
MORE FROM THE SOUTHEAST WITH MODELS PROMISING THAT THE MOISTURE WILL
SHIFT TO THE NORTH. FOR TONIGHT...THINK THERE WILL BE ANOTHER ROUND
OF NOCTURNAL STORMS BUT WILL BE MORE FOCUSED OVER THE EASTERN HALF
OF THE LITTLE COLORADO RIVER VALLEY...THE EASTERN MOGOLLON
RIM...WHITE MOUNTAINS AND NORTHERN GILA COUNTY. THE AIR MASS IS
APPARENTLY VERY UNSTABLE ACROSS THIS AREA AND A FAIRLY SIGNIFICANT
AREA OF LOW INERTIAL STABILITY IN THE UPPER LEVELS WILL REMAIN INTO
THE NIGHT. DEEP MOISTURE REMAINS OVER PORTIONS OF YAVAPAI AND
COCONINO COUNTIES AND ANY STORMS THAT FORM WILL PRODUCE HEAVY RAIN.
FOR SATURDAY...WITH SOME DRYING OVER THE NORTH...WOULD EXPECT A MORE
DIURNAL TREND TO CONVECTION AND SOMEWHAT LESS ACTIVITY (ALTHOUGH IT
REMAINS MOIST AND MID LEVEL LAPSE RATES REMAIN FAVORABLE). OVER
CENTRAL AND SOUTHERN PORTIONS OF THE CWA EXPECT SCATTERED TO
NUMEROUS STORMS WITH DEEP MOISTURE REMAINING OVER THE AREA. FOR
SUNDAY MOISTURE NORTHWARD WITH SOME INCREASE IN ACTIVITY. DAYTIME
TEMPERATURES WILL BE WARMER THE NEXT TWO DAYS AS HIGH PRESSURE
BUILDS.

IN THE EXTENDED...SUBTROPICAL RIDGE AXIS REMAINS ENTRENCHED OVER THE
SOUTHWEST UNITED STATES WITH MOIST AIR FROM MEXICO CONTINUING TO
MOVE INTO ARIZONA. AS A RESULT...WILL CONTINUE THE CHANCE OF SHOWERS
AND THUNDERSTORMS THROUGH THE EXTENDED.

MCCOLLUM

.FGZ...FLASH FLOOD WATCH UNTIL 800 PM MST FOR SOUTHWEST COCONINO
       COUNTY AND ALL OF YAVAPAI COUNTY.

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 10, 7:29 PM MSTSevere Thunderstorm WarningFGZYavapai41 min
Aug 10, 9:27 PM MSTSevere Thunderstorm WarningFGZYavapai33 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; radar from the NEXRAD Level II archive.