Alert archive / Arizona / Flash Flood Warnings in 2012

Flash Flood Warning 36, NWS Flagstaff, AZ

September 1, 2012Coconino County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Sep 1, 2012, 2:53 PM MST for Coconino County, Arizona. It was in force for 112 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
Sep 1, 2012, 2:53 PM MST (21:53 UTC)
Expired
Sep 1, 2012, 4:45 PM MST
In force
112 min
Issued by
NWS Flagstaff, AZ
Area
Storm-based polygon
Flood severity
None

County Coconino County, AZ

The radar

The Cedar City radar (KICX), 149 km from the middle of the area, began a volume at 21:55 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, 9.9 hours before the alert went out and 189 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 2012-09-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 325 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Flgstf/Belemont, AZ at 12:00Z on 2012-09-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 102 square meters per square second.19395878Sfc1 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
325 J/kg
Mixed-layer CIN
-86 J/kg
Mixed-layer LCL
1111 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
102 m²/s²
0-3 km storm-relative helicity
82 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.9

Open this sounding in Storm Lab

The text

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

145 
WGUS55 KFGZ 012153
FFWFGZ
AZC005-012345-
/O.NEW.KFGZ.FF.W.0036.120901T2153Z-120901T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
253 PM MST SAT SEP 1 2012

THE NATIONAL WEATHER SERVICE IN FLAGSTAFF HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTH CENTRAL COCONINO COUNTY IN NORTH CENTRAL ARIZONA...
  THIS INCLUDES THE CITY OF ANTELOPE CANYON NEAR SR 98...

* UNTIL 445 PM MST

* AT 246 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  FLASH FLOODING FROM A THUNDERSTORM OVER ANTELOPE CANYON. THE LOWER
  ANTELOPE CANYON AREA WILL BE AFFECTED THE MOST...WITH LESSER RAIN
  AMOUNTS SOUTH OF ROUTE 98. A HALF INCH TO THREE QUARTERS OF AN
  INCH OF RAINFALL WILL FALL WITH THIS STORM....AFFECTING AREAS TO
  THE EAST AND WEST OF ANTELOPE CREEK AS WELL. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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.

&&

LAT...LON 3693 11144 3694 11142 3691 11138 3687 11137
      3685 11142 3686 11146

$$
1 follow-up statement
590 
WGUS75 KFGZ 012345
FFSFGZ

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
445 PM MST SAT SEP 1 2012

AZC005-012349-
/O.EXP.KFGZ.FF.W.0036.000000T0000Z-120901T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
COCONINO AZ-
445 PM MST SAT SEP 1 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 445 PM MST FOR NORTH
CENTRAL COCONINO COUNTY...

AT 440 PM MST...FLAGSTAFF DOPPLER RADAR INDICATED NO FURTHER THREAT 
OF SIGNIFICANT RAINFALL IN THE ANTELOPE CANYON AREA. NO REPORTS OF 
SIGNIFICANT FLOODING HAVE BEEN RECEIVED FROM ANTELOPE CANYON BY THE 
NATIONAL WEATHER SERVICE IN FLAGSTAFF. WATER LEVELS IN THE ANTELOPE 
CANYON AREA AND SURROUNDING SIDE CANYONS MAY STILL BE SLIGHTLY 
HIGHER THAN NORMAL FOR THE NEXT FEW HOURS...HOWEVER...THE FLASH 
FLOOD WARNING WILL BE ALLOWED TO EXPIRE.

LAT...LON 3693 11144 3694 11142 3691 11138 3687 11137
      3685 11142 3686 11146

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 31, 5:30 PM MSTAreal Flood AdvisoryFGZYavapai3 hr
Aug 31, 6:26 PM MSTAreal Flood AdvisoryFGZCoconino3 hr
Sep 1, 12:12 PM MSTSevere Thunderstorm WarningFGZCoconino33 min
Sep 1, 1:27 PM MSTSevere Thunderstorm WarningFGZCoconino16 min
Sep 1, 1:56 PM MSTSevere Thunderstorm WarningFGZCoconino18 min
Sep 1, 2:57 PM MSTSevere Thunderstorm WarningFGZCoconino, Navajo17 min

Nearby

Flash Flood Warnings in Arizona, 2012Every flash flood warning in 2012

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.