Alert archive / Arizona / Severe Thunderstorm Warnings in 2000

Severe Thunderstorm Warning 8, NWS Flagstaff, AZ

July 21, 2000Yavapai County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Jul 21, 2000, 7:37 PM MST for Yavapai County, Arizona. It was in force for 23 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
Jul 21, 2000, 7:37 PM MST (02:37 UTC)
Expired
Jul 21, 2000, 8:00 PM MST
In force
23 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), 62 km from the middle of the area, began a volume at 02:39 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

Phoenix, AZ (KPSR), launched 00:00Z, 2.6 hours before the alert went out and 86 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, Phoenix, AZ at 00:00Z on 2000-07-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 676 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Phoenix, AZ at 00:00Z on 2000-07-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 19 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
676 J/kg
Mixed-layer CIN
-223 J/kg
Mixed-layer LCL
2929 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
19 m²/s²
0-3 km storm-relative helicity
82 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

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

509 
WUUS55 KFGZ 220245 COR
SVRFLG
AZC025-220300-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
737 PM MST FRI JUL 21 2000

THE NATIONAL WEATHER SERVICE IN FLAGSTAFF HAS ISSUED A

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

* UNTIL 800 PM MST

* AT 737 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM OVER EXTREME SOUTHEASTERN YAVAPAI COUNTY...OR
  ABOUT 25 MILES SOUTHWEST OF PAYSON...MOVING SOUTHWEST AT 5 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
5 MILES EAST OF HORSESHOE RESERVOIR AROUND 745 PM MST

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

LAT...LON 3411 11184 3398 11169 3422 11136 3438 11155

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 21, 2:30 PM MST, 5 hours 7 minutes earlier.

Area forecast discussion, Jul 21, 2:30 PM MST, 5 hours 7 minutes before
NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
230 PM MST FRI JUL 21 2000

SYNOPSIS...A STRONG HIGH PRESSURE CELL WILL REMAIN CENTERED OVER
ARIZONA THIS WEEKEND. THE CLOCKWISE CIRCULATION AROUND THE HIGH WILL
CONTINUE TO BRING IN MAINLY MID LEVEL MOISTURE TO THE WESTERN HALF
OF ARIZONA ON SATURDAY. THIS MID LEVEL MOISTURE IS EXPECTED TO
SPREAD EASTWARD INTO THE NAVAJO NATION SATURDAY NIGHT AND SUNDAY.
THE MID LEVEL MOISTURE WILL ALLOW A SLIGHT CHANCE OF HIGH BASED
THUNDERSTORMS BOTH SATURDAY AND SUNDAY AFTERNOON. ON MONDAY... A DRY
SOUTHWEST FLOW ALOFT IS EXPECTED TO RETURN TO THE STATE...LASTING
THROUGH MID WEEK.

DISCUSSION...ON THE LARGE SCALE... THE WARM WARM HIGH PRESSURE
SYSTEM EXPECTED TO SIT OVER ARIZONA THIS WEEKEND. THE FORECASTS WERE
BASED ON THE ETA...ALTHOUGH NGM SIMILAR WITH LARGE SCALE FEATURES.
WHAT WE HAVE NOW IS AN EAST TO WEST H5 RIDGE AXIS STRETCHING FROM
NEW MEXICO INTO SOUTHEASTERN CAL. THE GULF SURGE INTO THE COLORADO
RIVER VALLEY ALSO CONTINUES THIS AFTERNOON...WITH THE REMNANTS OF AN
EASTERLY WAVE HEADED TOWARD PALM SPRINGS. A LINE OF CONVECTION HAS
DEVELOPED ALONG THE MOGOLLON RIM THIS AFTERNOON AND WILL LIKELY
SWEEP SOUTHWARD LATER TODAY. POPS TONIGHT WILL BE ADJUSTED
ACCORDINGLY.

ON SATURDAY...MID LEVEL MOISTURE (H5 TO H3) ON THE WESTERN PORTION
OF THE RIDGE AXIS EXPECTED TO MOVE NORTHWARD TOWARDS UTAH. THIS DUE
THE RIDGE AXIS BECOMING ALIGNED MORE NORTH TO SOUTH...AND MID LEVEL
WINDS BECOMING SOUTHERLY. AREAL EXTENT OF THE LOW LEVEL MOISTURE
STILL A WILD CARD. WE DO FEEL THAT THE FAR WESTERN PORTIONS OF THE
CWA HAVE SHOT AT SOME LIQUID HITTING THE GROUND SATURDAY. ELSEWHERE
ITS HIGH BASED CONVECTION. IT LOOKS LIKE ANOTHER HOT ONE IN THE
NORTHEAST WITH LITTLE CLOUD COVER.

SATURDAY NIGHT AND SUNDAY THE MID LEVEL WINDS BECOMING SOUTHWESTERLY
WITH TIME AND EXPAND THE MID LEVEL MOISTURE INTO NORTHEAST ARIZONA.
THUS ALL AREAS WILL HAVE AT LEAST A SLIGHT CHANCE OF AFTERNOON
THUNDER.

IN THE EXTENDED... EXTENDED PROGS IN SIMILAR AGREEMENT AS THEY KEEP
A H5 HIGH CENTERED OVER NEW MEXICO AND DRY SOUTHWEST FLOW ALOFT OVER
THE NORTHERN PORTIONS OF AZ. SO IT LOOKS DRY WITH A SLOW WARMING
TREND THROUGH MID WEEK.

.FGZ...NONE.

JDL

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 22, 3:17 PM MSTSevere Thunderstorm WarningFGZGila28 min
Jul 22, 4:29 PM MSTSevere Thunderstorm WarningFGZYavapai46 min

Nearby

Severe Thunderstorm Warnings in Arizona, 2000Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.