Alert archive / Arizona / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 40, NWS Flagstaff, AZ

July 25, 2001Coconino County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Jul 25, 2001, 11:15 AM MST for Coconino County, Arizona. It was in force for 30 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 25, 2001, 11:15 AM MST (18:15 UTC)
Expired
Jul 25, 2001, 11:45 AM MST
In force
30 min
Issued by
NWS Flagstaff, AZ
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Coconino County, AZ

The radar

The Flagstaff radar (KFSX), 32 km from the middle of the area, began a volume at 18:18 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, 6.3 hours before the alert went out and 109 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 2001-07-25Temperature 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 2001-07-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -2 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
2086 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
-2 m²/s²
0-3 km storm-relative helicity
-6 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.

000 
WUUS55 KFGZ 251816
SVRFLG

AZC005-251845-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
1115 AM MST WED JUL 25 2001

THE NATIONAL WEATHER SERVICE HAS ISSUED A

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

* UNTIL 1145 AM MST

* AT 1115 AM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM OVER EXTREME SOUTHEASTERN COCONINO COUNTY...OR
  ABOUT 18 MILES NORTH OF FOREST LAKES...MOVING NORTHWEST AT 20 MPH.

* THE SEVERE THUNDERSTORM WILL AFFECT OR PASS CLOSE TO...
RURAL SOUTHEASTERN COCONINO COUNTY AT 1130 AM MST

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.

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

LAT...LON 3450 11089 3460 11074 3481 11075 3477 11099

MAS

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 25, 9:15 AM MST, 2 hours earlier.

Area forecast discussion, Jul 25, 9:15 AM MST, 2 hours before
NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
915 AM MST WED JUL 25 2001

.SYNOPSIS...EXPECT WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY TODAY
AS MOISTURE LEVELS HAVE INCREASED SUBSTANTIALLY OVERNIGHT. SHOWERS
AND THUNDERSTORMS WILL CONTINUE OVERNIGHT AND INTO THURSDAY AS MOIST
SOUTHERLY FLOW CONTINUES ACROSS THE AREA. A DRIER WESTERLY FLOW WILL
DEVELOP BY THE WEEKEND...WITH A CHANCE OF SHOWERS AND THUNDERSTORMS
MAINLY OVER THE HIGHER TERRAIN.

.DISCUSSION...UPPER LOW OVER SOUTHERN CALIFORNIA WILL SLOWLY MOVE
EAST-NORTHEAST THROUGH THURSDAY MORNING. STRONG SOUTHERLY FLOW SET
UP THIS MORNING AHEAD OF THE LOW OVER WESTERN ARIZONA. 65KT JET
STREAK MOVING AROUND THE LOW COUPLED WITH LOW-LEVEL FLOW BROUGHT A
RAPID AND SUBSTANTIAL INCREASE IN MOISTURE TO THE AREA OVERNIGHT.
RADAR AND SATELLITE ALREADY QUITE ACTIVE...AND WILL NEED MAJOR
UPDATES TO THE ZONES THIS MORNING. EXPECT MAIN TROUBLE AREA TO BE
WEST AND NORTHWEST OF THE EASTERN RIM AS THIS AREA IS UNDER MODERATE
DYNAMICS ALL DAY. EXPECT ACTIVITY TO CONTINUE OVERNIGHT AND INTO
THURSDAY...WITH A SLIGHT EASTWARD SHIFT IN THE MOISTURE BOUNDARY.
FIRST PERIOD UPDATES 0ON THE WAY. PETERSON.

.FGZ...NONE.

In the hours before

Special weather statement, Jul 25, 9:30 AM MST, 1 hour 45 minutes before
AZZ004>018-037>040-251930-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
930 AM MST WED JUL 25 2001

...WIDESPREAD SHOWERS AND THUNDERSTORMS TODAY...ESPECIALLY OVER THE
CENTRAL PORTIONS OF ARIZONA...

DEEP MOISTURE MOVED INTO MUCH OF THE REGION OVERNIGHT AND WILL
CONTINUE TO REMAIN IN PLACE INTO EARLY THURSDAY. THIS MOISTURE WILL
BRING WIDESPREAD SHOWERS AND THUNDERSTORMS TO MUCH OF THE AREA
TODAY. MOST OF THE STRONGER STORMS ARE EXPECTED MAINLY WEST AND
NORTHWEST OF THE EASTERN MOGOLLON RIM. THESE STORMS ARE CAPABLE OF
PRODUCING VERY HEAVY RAINS AND SOME HAIL.

AN UPPER LOW PRESSURE SYSTEM LOCATED JUST SOUTH OF LAS VEGAS WILL
BRING SOME COLDER AIR ALOFT TO THE REGION BY THIS AFTERNOON. THIS
WILL MEAN THAT THERE IS A POSSIBILITY OF ISOLATED SEVERE
THUNDERSTORMS CONTAINING LARGE HAIL. THE MAIN THREAT FOR THIS TYPE
OF STORM WILL BE ROUGHLY WEST OF A LINE FROM THE GRAND CANYON TO
mHEBER.

SPOTTER REPORTS OF EXCESSIVE RAINFALL AMOUNTS AND SEVERE WEATHER
SHOULD BE RELAYED TO THE NATIONAL WEATHER SERVICE.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 25, 4:40 PM MSTSevere Thunderstorm WarningFGZYavapai35 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.