Alert archive / Arizona / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 71, NWS Flagstaff, AZ

August 19, 2001Coconino County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Aug 19, 2001, 2:29 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 outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties.

The facts

Issued
Aug 19, 2001, 2:29 PM MST (21:29 UTC)
Expired
Aug 19, 2001, 3:00 PM MST
In force
31 min
Issued by
NWS Flagstaff, AZ
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Coconino County, AZ

The nearest sounding before it

Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 9.5 hours before the alert went out and 89 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 2001-08-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 208 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 2001-08-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 66 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
208 J/kg
Mixed-layer CIN
-189 J/kg
Mixed-layer LCL
2231 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
66 m²/s²
0-3 km storm-relative helicity
81 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.

429 
WUUS55 KFGZ 192130
SVRFLG
AZC005-192200-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
229 PM MST SUN AUG 19 2001

THE NATIONAL WEATHER SERVICE HAS ISSUED A

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

* UNTIL 300 PM MST

* AT 229 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM OVER EXTREME SOUTHEASTERN COCONINO COUNTY...OR
  ABOUT 18 MILES NORTHEAST OF CLINTS WELL.  THE STORM WAS NEARLY
  STATIONARY.

* THE SEVERE THUNDERSTORM WILL AFFECT OR PASS CLOSE TO...
STATE ROUTE 87 NEAR BLUE RIDGE CAMPGROUNDS 

HAIL UP TO ONE INCH IN DIAMETER HAS BEEN REPORTED WITH THIS STORM. 
IF YOU ARE IN THE PATH OF THE STORM...SEEK SUBSTANTIAL SHELTER 
IMMEDIATELY. 

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

LAT...LON 3471 11118 3458 11103 3471 11083 3482 11107

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 19, 9:30 AM MST, 4 hours 59 minutes earlier.

Area forecast discussion, Aug 19, 9:30 AM MST, 4 hours 59 minutes before
NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
930 AM MST SUN AUG 19 2001

.SYNOPSIS...HIGH PRESSURE CURRENTLY OVER THE DESERT SOUTHWEST WILL
MOVE TO THE EAST OF ARIZONA TODAY. AS A RESULT...SOUTHERLY FLOW
ALOFT WILL BRING AN INCREASE IN MONSOONAL MOISTURE TO THE STATE. AN
UPPER LEVEL DISTURBANCE EMBEDDED IN THE FLOW WILL RESULT IN AN
UPSWING IN SHOWERS AND THUNDERSTORMS...ESPECIALLY ON MONDAY. LOOK
FOR COOLER TEMPERATURES ACROSS THE NORTHLAND BY MONDAY. A WESTERLY
FLOW ALOFT WILL BRING DRIER AND WARMER WEATHER TO THE STATE BY THE
MIDDLE OF NEXT WEEK.

.DISCUSSION...HIGH PRESSURE CURRENTLY NEAR NORTHEAST AZ WILL MOVE TO
THE EAST TODAY WHICH WILL RESULT IN A MORE SOUTHERLY FLOW AND AN
INCREASE IN MOISTURE ACROSS AZ. MOISTURE FLUX ACROSS AZ ALREADY IN
PROGRESS THIS MORNING AS SFC OBS INDICATE A 2 TO 4 DEGREE INCREASE
IN DEWPTS FROM YESTERDAY MORNING. GOES PRECIPITABLE WATER (PW)
IMAGERY AND MORNING RAOBS ALSO SHOWING 1 TO 1.6 INCHES OF PW IN THE
LOWER DESERTS...NORTHWARD ALONG THE COLORADO RIVER WITH 0.6 TO 0.8
INCH PW OVER NORTHERN AZ. MESOETA ALSO PICKS UP THE DISTURBANCE
EMBEDDED IN THE FLOW JUST SOUTH OF THE AZ BORDER.  THIS FEATURE
PROGGED TO MOVE NORTHWARD INTO SOUTH CENTRAL AZ TODAY...THEN INTO
NORTHERN AZ TONIGHT THROUGH EARLY MONDAY. THUS...EXPECT MONDAY TO BE
A CONVECTIVE DAY ACROSS THE FORECAST AREA.  FLOW BECOMES WESTERLY ON
TUESDAY AS TROF OF LOW PRESSURE MOVES INTO THE COAST AND ADVECTS
DRIER AIR INTO THE STATE.  ETA/AVN SWEEP THE MOISTURE OUT OF THE
FORECAST AREA BY WEDNESDAY. ETA/AVN SHOW AN ATTENDANT 50 KT JET
CLIPPING THE NORTHWEST PART OF THE STATE ON TUESDAY.  THIS FEATURE
WILL BEAR WATCHING AS ENERGETICS INTERACT WITH RESIDUAL MOISTURE. TW

.FGZ...NONE.

In the hours before

Special weather statement, Aug 19, 8:45 AM MST, 5 hours 44 minutes before
AZZ004>018-037>040-191930-
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
845 AM MST SUN AUG 19 2001

...MONSOON MOISTURE RETURNS TO NORTHERN ARIZONA TODAY...

HIGH PRESSURE WILL MOVE TO THE EAST AND ALLOW A MOIST SOUTHEASTERLY
FLOW TO DEVELOP OVER ARIZONA TODAY. MONSOONAL MOISTURE CURRENTLY
LOCATED ALONG THE ARIZONA-MEXICO BORDER WILL BEGIN TO MOVE NORTHWARD
TODAY AND TONIGHT.

EXPECT SCATTERED SHOWERS TO DEVELOP OVER AND SOUTH OF THE MOGOLLON
RIM THIS AFTERNOON...BECOMING MORE WIDESPREAD THIS EVENING AND
SPREADING NORTHWARD TO THE UTAH BORDER. SOME OF THESE STORMS WILL BE
CAPABLE OF PRODUCING STRONG AND GUSTY WINDS.

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 19, 3:05 PM MSTSevere Thunderstorm WarningFGZCoconino25 min
Aug 19, 4:26 PM MSTSevere Thunderstorm WarningFGZGila34 min
Aug 19, 4:59 PM MSTSevere Thunderstorm WarningFGZGila31 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.