Alert archive / Arizona / Flash Flood Warnings in 1998

Flash Flood Warning 16, NWS Flagstaff, AZ

September 11, 1998Coconino County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Sep 11, 1998, 11:31 AM MST for Coconino County, Arizona. It was in force for 119 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Sep 11, 1998, 11:31 AM MST (18:31 UTC)
Expired
Sep 11, 1998, 1:30 PM MST
In force
119 min
Issued by
NWS Flagstaff, AZ
Area
Whole counties

County Coconino County, AZ

The nearest sounding before it

Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 6.5 hours before the alert went out and 68 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 1998-09-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 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 1998-09-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 31 square meters per square second.193958Sfc1 km3 km6 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
1435 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
31 m²/s²
0-3 km storm-relative helicity
158 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 
TTAA00 KFLG 111834
FFWFLG
AZC005-112030-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
1131 AM MST FRI SEP 11 1998

THE NATIONAL WEATHER SERVICE IN FLAGSTAFF HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHWESTERN COCONINO COUNTY IN NORTH CENTRAL ARIZONA INCLUDING
  THE VILLAGE OF SUPAI

* UNTIL 130 PM MST

* AT 1130 AM MST...NATIONAL WEATHER SERVICE DOPPLER WEATHER RADAR
  DETECTED ANOTHER AREA OF LOCALLY HEAVY RAIN AND EMBEDDED
  THUNDERSTORMS MOVING ACROSS NORTHWESTERN COCONINO COUNTY
  INCLUDING HAVASUPAI CANYON AND THE VILLAGE OF SUPAI.

* SPOTTER REPORTS FROM THE VILLAGE OF SUPAI REPORTED HEAVY RAIN AT
  1130 AM WITH STREAMS RISING.  THUS...THE FLASH FLOOD WARNING FOR
  THIS AREA HAS BEEN EXTENDED.

IF YOU ARE IN THE WARNING AREA... MOVE TO HIGHER GROUND AT ONCE.
DO NOT DRIVE ACROSS WATER COVERED ROADS. AVOID ALL AREAS SUBJECT
TO FLOODING.

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 Sep 11, 9:00 AM MST, 2 hours 31 minutes earlier.

Area forecast discussion, Sep 11, 9:00 AM MST, 2 hours 31 minutes before
NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
900 AM MST FRI SEP 12 1998

SYNOPSIS...A UPPER LEVEL LOW PRESSURE SYSTEM ALONG THE
CALIFORNIA/NEVADA BORDER WILL KEEP A VERY MOIST SOUTHERLY FLOW ACROSS
NORTHERN ARIZONA TODAY FOR MORE CLOUDS...SHOWERS AND THUNDERSTORMS
OVER THE AREA.

DISCUSSION...THUNDERSTORMS CONTINUE ACROSS YAVAPAI AND WESTERN
COCONINO COUNTIES THIS MORNING.  LOCALLY HEAVY RAINFALL...UP TO 1
INCH HAS BEEN REPORTED AT SEVERAL LOCATIONS IN WESTERN PART OF CWFA
SINCE 12Z. VORT MAX THAT DEVELOPED OFF NORTHERN TIP OF BAJA CALIF
LAST NIGHT IS MOVING NORTH ALONG WESTERN AZ ATTM.  THIS FEATURE
COUPLED WITH RIGHT REAR ENTRANCE OF 250MB JET...VERY MOIST SOUTHERLY
FLOW...PRECIP WATER IN 0.75 TO 1.25 INCH RANGE OVER WESTERN CWFA
PROMPTED FLASH FLOOD WATCH FOR WESTERN ZONES OF CWFA AND FLASH FLOOD
WARNING FOR HAVASUPAI CANYON AND SUPAI VILLAGE.  UPPER LEVEL LOW IN
NEVADA PROGGED TO LIFT OUT OF AREA SAT PM TIME FRAME...BUT SLOW
PROGRESS EXPECTED DUE TO BLOCKING DOWNSTREAM RIDGE.  NEXT FEATURE OF
CONCERN FOR WEEKEND IS REMNANTS OF TS FRANCES AS MOISTURE EXPECTED TO
MOVE INTO EASTERN AZ.  BOTTOM LINE...NORTHERN AZ EXPECTED TO STAY WET
NEXT 48 HRS. TW

.FLG...FLASH FLOOD WATCH FOR YAVAPAI AND WESTERN COCONINO UNTIL 8PM
MST.

In the hours before

Special weather statement, Sep 11, 9:30 AM MST, 2 hours 1 minute before
AZZ004>018-101900-

AREA THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
930 AM MST FRI SEP 11 1998

...SHOWERS...THUNDERSTORMS AND LOCALLY HEAVY RAINFALL ACROSS NORTHERN
ARIZONA TODAY...

SPOTTER REPORTS OF SIGNIFICANT THUNDERSTORM ACTIVITY AND RAINFALL
AMOUNTS REQUESTED.

SEVERAL INGREDIENTS HAVE COME TOGETHER FOR STRONG THUNDERSTORMS AND
LOCALLY HEAVY RAINFALL OVER NORTHWESTERN ARIZONA TODAY.  AN UPPER
LEVEL DISTURBANCE MOVING NORTH ACROSS WESTERN ARIZONA IN CONJUNCTION
WITH A VERY MOIST AIRMASS AND STRONG SOUTHERLY WINDS WILL PRODUCE
SHOWERS AND THUNDERSTORMS ACROSS NORTHWEST ARIZONA TODAY.  LOCALLY
HEAVY RAINFALL IS EXPECTED ACROSS YAVAPAI AND COCONINO COUNTIES
THROUGHOUT THE DAY.  THESE STORMS WILL MOVE TO THE NORTH AT 20 TO 25
MPH.  A SOMEWHAT DRIER AIRMASS RESIDES OVER NAVAJO AND APACHE
COUNTIES. SHOWERS AND THUNDERSTORMS THAT DEVELOP OVER THE
NORTHEASTERN PART OF THE STATE ARE NOT EXPECTED TO BE AS STRONG AS
STORMS IN THE WESTERN PART OF THE STATE.

TW

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 10, 7:28 PM MSTSevere Thunderstorm WarningFGZCoconino32 min
Sep 11, 8:23 AM MSTFlash Flood WarningFGZCoconino3 hr
Sep 11, 1:27 PM MSTFlash Flood WarningFGZCoconino93 min

Nearby

Flash Flood Warnings in Arizona, 1998Every flash flood warning in 1998

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.