Alert archive / Arizona / Flash Flood Warnings in 2012

Flash Flood Warning 7, NWS Flagstaff, AZ

July 20, 2012Coconino County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Jul 20, 2012, 3:40 PM MST for Coconino County, Arizona. It was in force for 95 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 20, 2012, 3:40 PM MST (22:40 UTC)
Expired
Jul 20, 2012, 5:15 PM MST
In force
95 min
Issued by
NWS Flagstaff, AZ
Area
Storm-based polygon
Flood severity
None

County Coconino County, AZ

The radar

The Cedar City radar (KICX), 152 km from the middle of the area, began a volume at 22:42 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, 10.7 hours before the alert went out and 187 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 2012-07-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 110 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 2012-07-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 5 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
110 J/kg
Mixed-layer CIN
-130 J/kg
Mixed-layer LCL
1736 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
5 m²/s²
0-3 km storm-relative helicity
44 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.

818 
WGUS55 KFGZ 202240
FFWFGZ
AZC005-210015-
/O.NEW.KFGZ.FF.W.0007.120720T2240Z-120721T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
340 PM MST FRI JUL 20 2012

THE NATIONAL WEATHER SERVICE IN FLAGSTAFF HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTH CENTRAL COCONINO COUNTY IN NORTH CENTRAL ARIZONA...  
  THIS INCLUDES ANTELOPE CANYON NEAR STATE ROUTE 98...

* UNTIL 515 PM MST

* AT 331 PM MST...NATIONAL WEATHER SERVICE RADAR INDICATED A 
THUNDERSTORM PRODUCING HEAVY RAINFALL IN THE ANTELOPE CANYON 
DRAINAGE. FLASH FLOODING IS LIKELY IN ANTELOPE CANYON.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED ANTELOPE
CANYON...LE CHEE.

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 3694 11145 3694 11136 3678 11130 3679 11144

$$
JJ
2 follow-up statements
588 
WGUS75 KFGZ 202341
FFSFGZ

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
441 PM MST FRI JUL 20 2012

AZC005-210015-
/O.CON.KFGZ.FF.W.0007.000000T0000Z-120721T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
COCONINO AZ-
441 PM MST FRI JUL 20 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 515 PM MST FOR NORTH
CENTRAL COCONINO COUNTY...

AT 433 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
ADDITIONAL SHOWERS DEVELOPING OVER THE ANTELOPE CANYON DRAINAGE.
RAINFALL ESTIMATES FROM EARLIER STORMS RANGED UP TO ONE INCH WHICH
WILL CAUSE FLOODING IN ANTELOPE CANYON. 

LOCATIONS IN THE WARNING INCLUDE ANTELOPE CANYON NEAR STATE ROUTE 
98.

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 3694 11145 3694 11136 3678 11130 3679 11144

$$
JJ
887 
WGUS75 KFGZ 210014
FFSFGZ

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
514 PM MST FRI JUL 20 2012

AZC005-210021-
/O.EXP.KFGZ.FF.W.0007.000000T0000Z-120721T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
COCONINO AZ-
514 PM MST FRI JUL 20 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 515 PM MST FOR NORTH
CENTRAL COCONINO COUNTY...

HEAVY RAIN HAS ENDED ACROSS THE ANTELOPE CANYON DRAINAGE. 
STORM RUNOFF SHOULD CONTINUE FOR ANOTHER ONE TO TWO 
HOURS...AND PEOPLE IN THIS AREA SHOULD KEEP OUT OF SLOT 
CANYONS THIS EVENING.

LAT...LON 3694 11145 3694 11136 3678 11130 3679 11144

$$
JJ

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 20, 11:34 AM MSTSpecial Weather StatementFGZ26 min
Jul 20, 12:03 PM MSTAreal Flood AdvisoryFGZApache, Navajo117 min
Jul 20, 1:27 PM MSTSpecial Weather StatementFGZCoconino48 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.