Alert archive / Arizona / Flash Flood Warnings in 2003

Flash Flood Warning 6, NWS Flagstaff, AZ

July 31, 2003Navajo County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Jul 31, 2003, 6:44 PM MDT for Navajo County, Arizona. It was in force for 61 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jul 31, 2003, 6:44 PM MDT (00:44 UTC)
Expired: Jul 31, 2003, 7:45 PM MDT
In force: 61 min
Issued by: NWS Flagstaff, AZ
Area: Counties, with a storm outline in the text

County Navajo County, AZ

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this flash flood warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Flgstf/Belemont, AZ (KFGZ), launched 00:00Z, 0.7 hours before the alert went out and 195 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 149 J/kg
Mixed-layer CIN: -11 J/kg
Mixed-layer LCL: 1823 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: -3 m²/s²
0-3 km storm-relative helicity: 53 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.

000 
WGUS55 KFGZ 010046
FFWFGZ
AZC017-010245-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
544 PM MST THU JUL 31 2003

THE NATIONAL WEATHER SERVICE IN FLAGSTAFF HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHEASTERN NAVAJO COUNTY IN NORTHEAST ARIZONA

* UNTIL 745 PM MST

* AT 539 PM MST...WEATHER SERVICE DOPPLER RADAR INDICATED VERY HEAVY
  RAIN IN THE SILVER CREEK AREA NORTHEAST OF SHOW LOW. THE AREA OF 
  HEAVY RAIN WAS MOVING SLOWLY NORTHWESTWARD...BUT ADDITIONAL STORMS
  WILL MOVE INTO THE AREA FROM THE SOUTHEAST.
  
EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF CREEKS
AND STREAMS INCLUDING SILVER CREEK...ROADS AND ROADSIDE CULVERTS. 
THE HEAVY RAINS COULD ALSO TRIGGER ROCK AND MUDSLIDES IN STEEP TERRAIN.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY
AUTOMOBILE. IF YOUR VEHICLE STALLS, ABANDON IT IMMEDIATELY AND SEEK
HIGHER GROUND.

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

LAT...LON 3428 11002 3429 10986 3439 10986 3444 11007

$$

What forecasters said that day

The local office's own words before this flash flood 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 flash flood warning went out at Jul 31, 3:15 PM MDT, 3 hours 29 minutes earlier.

Area forecast discussion, Jul 31, 3:15 PM MDT, 3 hours 29 minutes before

NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
215 PM MST THU JUL 31 2003

.SYNOPSIS...THE ATMOSPHERE WILL REMAIN MOIST AND UNSTABLE INTO THE
EARLY PART OF NEXT WEEK. LOOK FOR DAILY SHOWER AND THUNDERSTORM
ACTIVITY TO CONTINUE...AND FOR TEMPERATURES TO REMAIN NEAR NORMAL
VALUES.

.DISCUSSION...CONVECTION SLOW STARTING TODAY IN THE RAIN COOLED
AIRMASS FROM LAST NIGHT...BUT WE ARE GETTING UNDERWAY NOW. EXPECT AN
ACTIVE AFTERNOON AND EVENING...AS MENTIONED THIS MORNING...A LARGE
AREA OF INERTIAL INSTABILITY COUPLED WITH AN EASTERLY WAVE MOVING
INTO SOUTHEAST ARIZONA WILL CAUSE CONVECTION TO CONTINUE TO RAMP UP
IN THE NEXT SEVERAL HOURS. NO REAL BREAK IN STORE FRIDAY OR SATURDAY
AS A STRONG S/WV IN THE GULF OF CALIFORNIA MOVES INTO WESTERN
ARIZONA. FLASH FLOOD WATCH STILL IN EFFECT...AND WOULD NOT BE
SHOCKED TO SEE ANOTHER ONE FOR FRIDAY. A WEAK DRYING TREND WILL
START SUNDAY AND CONTINUE INTO NEXT WEEK AS WESTERLY FLOW ALOFT
DEVELOPS. DO NOT THINK WE WILL COMPLETELY SCOUR OUT...AND THE HIGH
REDEVELOPS LATE IN THE PERIOD...SO THE BREAK WILL BE SHORT-LIVED.
PETERSON.

.FGZ...FFA AZ ZONES 8/37/38/15/17 UNTIL 10 PM MST.

.CODED TEMPERATURES/POPS FOR SELECTED CITIES IN NORTHERN ARIZONA

CITY             TEMPERATURES LO/HI           PROBABILITY OF PRECIP
                 TON FRI   SAT     SUN        TON FRI   SAT     SUN
FLAGSTAFF        054/075 053/074 055/078      050 060 050 060 040 050
WINSLOW          063/086 063/085 064/089      040 040 040 040 030 030
PRESCOTT         058/083 058/084 060/088      050 050 040 050 040 040
PAGE             072/095 072/093 072/097      030 030 030 030 020 020
WINDOW ROCK      055/079 054/078 053/082      030 040 030 050 030 040
CANYON DE CHELLY 065/085 064/084 063/088      030 030 030 030 020 030
COTTONWOOD       066/094 066/095 068/099      040 040 030 040 030 030
GRAND CANYON     053/077 052/076 054/080      050 050 040 050 040 040
GREER            050/071 049/070 051/074      050 060 050 060 050 060
HEBER            055/080 054/079 056/083      050 060 050 060 040 050
JACOB LAKE       054/073 053/072 055/076      050 050 040 040 030 030
NAVAJO N.M.      059/079 058/078 057/082      040 040 040 040 030 040
PAYSON           059/088 059/089 061/093      040 040 040 040 030 030
SEDONA           064/092 064/093 066/097      040 040 030 040 030 030
SELIGMAN         051/086 051/087 053/091      050 050 040 040 030 030
SHOW LOW         062/081 061/080 063/084      050 060 050 060 050 060
ST. JOHNS        058/080 058/079 059/083      050 050 050 050 040 050
WUPATKI N.M.     066/088 066/087 067/091      040 040 040 040 030 030

Hazardous weather outlook, Jul 31, 11:05 AM MDT, 7 hours 39 minutes before

AZZ004>018-037>040-010200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
1005 AM MST THU JUL 31 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR APACHE...COCONINO...NORTHERN
GILA...NAVAJO...AND YAVAPAI COUNTIES IN NORTHERN ARIZONA.

.DAY ONE...TODAY

...FLASH FLOOD WATCH FROM NOON MST UNTIL 10 PM MST FOR THE NORTHERN
TWO THIRDS OF YAVAPAI COUNTY...WESTERN MOGOLLON RIM...OAK CREEK AND
SYCAMORE CANYONS...AND THE WHITE MOUNTAINS...

A MOISTURE RICH AIRMASS REMAINS OVER THE STATE TODAY. WIDESPREAD
SHOWERS AND THUNDERSTORMS ARE EXPECTED ACROSS MUCH OF THE REGION BY
LATE MORNING THROUGH THE EVENING HOURS. ISOLATED THUNDERSTORMS MAY
PRODUCE TORRENTIAL RAIN...ESPECIALLY OVER PORTIONS OF THE MOGOLLON
RIM AND YAVAPAI COUNTY. THESE STRONGER STORMS MAY ALSO CONTAIN HAIL
UP TO AN INCH IN DIAMETER...AND DANGEROUS LIGHTNING.

DUE TO THE HEAVY RAIN THAT FELL IN YAVAPAI COUNTY WEDNESDAY...AS
WELL AS PORTIONS OF THE MOGOLLON RIM...A FLASH FLOOD WATCH HAS BEEN
ISSUED FOR THESE SAME AREAS TODAY.

THUNDERSTORMS WILL DEVELOP FIRST OVER THE WHITE MOUNTAINS AND
EASTERN RIM...AS WELL AS CENTRAL YAVAPAI COUNTY. DEVELOPMENT IN
THESE AREAS IS EXPECTED BY 11 AM MST. STORMS WILL THEN SPREAD INTO
THE REMAINING AREAS OF NORTHERN ARIZONA THROUGH THE AFTERNOON. STORM
MOTION WILL BE TO THE NORTHWEST TODAY...AS WINDS HAVE SHIFTED TO THE
SOUTHEAST OVERNIGHT.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

LITTLE CHANGE IS SEEN IN THE MOIST AND UNSTABLE ATMOSPHERE OVER THE
REGION THROUGH THE PERIOD. THUNDERSTORMS ARE EXPECTED TO DEVELOP
EACH DAY. HEAVY RAIN PRODUCING STORMS ARE LIKELY AGAIN FRIDAY AND
EVEN SATURDAY...SO THE THREAT FOR FLOODING WILL REMAIN AT LEAST
MODERATE.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

DEFINITION OF HAZARDOUS WEATHER...A WEATHER EVENT POSING A THREAT
TO LIFE AND PROPERTY.

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 1, 5:30 PM MDT	Flash Flood Warning	FGZ	Navajo	15 min

Nearby

Flash Flood Warnings in Arizona, 2003 Every flash flood warning in 2003

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.