Alert archive / Arizona / Flash Flood Warnings in 2011

Flash Flood Warning 56, NWS Tucson, AZ

August 31, 2011Pinal County, Arizona

NWS Tucson, AZ issued this flash flood warning at Aug 31, 2011, 6:09 PM MST for Pinal County, Arizona. It was in force for 111 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: Aug 31, 2011, 6:09 PM MST (01:09 UTC)
Expired: Aug 31, 2011, 8:00 PM MST
In force: 111 min
Issued by: NWS Tucson, AZ
Area: Storm-based polygon
Flood severity: None

County Pinal County, AZ

The radar

The Tucson radar (KEMX), 81 km from the middle of the area, began a volume at 01:09 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

Tuscon, AZ (KTUS), launched 00:00Z, 1.2 hours before the alert went out and 55 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: 69 J/kg
Mixed-layer CIN: -97 J/kg
Mixed-layer LCL: 3837 m above ground
0-6 km bulk shear: 11 kt
0-1 km storm-relative helicity: -60 m²/s²
0-3 km storm-relative helicity: -71 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.

175 
WGUS55 KTWC 010109
FFWTWC
AZC021-010300-
/O.NEW.KTWC.FF.W.0056.110901T0109Z-110901T0300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE TUCSON AZ
609 PM MST WED AUG 31 2011

THE NATIONAL WEATHER SERVICE IN TUCSON HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHEASTERN PINAL COUNTY IN SOUTH CENTRAL ARIZONA...

* UNTIL 800 PM MST

* AT 600 PM MST...A TRAINED WEATHER SPOTTER ESTIMATED THAT OVER TWO  
  INCHES OF RAIN HAS OCCURRED IN THE CAMPO BONITO AREA. RADAR        
  ESTIMATES HAVE BEEN OVER ESTIMATING RAINFALL. REALISTIC AMOUNTS OF 
  1.5 TO 2 INCHES IS NOT UNLIKELY. RUNOFF FROM THESE STORMS WILL     
  FLOW INTO THE WASHES THAT FEED INTO THE SAN PEDRO RIVER.   

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO SAN MANUEL

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF WASHES
AND STREAMS...COUNTRY ROADS...AS WELL AS FARMLAND ALONG THE BANKS OF
CREEKS AND STREAMS.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLASH FLOODING IS OBSERVED ACT QUICKLY. MOVE
UP TO HIGHER GROUND TO ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS
SUBJECT TO FLOODING WHEN WATER BEGINS RISING.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY.

&&

LAT...LON 3267 11072 3273 11053 3252 11057 3252 11081

$$

2 follow-up statements

654 
WGUS75 KTWC 010147
FFSTWC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE TUCSON AZ
647 PM MST WED AUG 31 2011

AZC021-010300-
/O.CON.KTWC.FF.W.0056.000000T0000Z-110901T0300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
PINAL AZ-
647 PM MST WED AUG 31 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 800 PM MST FOR
SOUTHEASTERN PINAL COUNTY...

AT 637 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE A THUNDERSTORM PRODUCING VERY HEAVY RAIN FROM CAMPO BONITO 
TO SAN MANUEL. EARLIER THIS EVENING A TRAINED WEATHER SPOTTER WITH A 
RAIN GAUGE NEAR CAMPO BONITO REPORTED RECEIVING THREE AND A HALF 
INCHES OF RAIN WITH THIS STORM. WASHES FLOWING TOWARD THE SAN PEDRO 
RIVER WILL BE SWOLLEN WITH WATER FOR ANOTHER HOUR OR TWO.    

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...COUNTRY ROADS...AS WELL AS FARMLAND ALONG THE
BANKS OF CREEKS AND STREAMS.

&&

LAT...LON 3267 11072 3273 11053 3252 11057 3252 11081

$$

907 
WGUS75 KTWC 010304
FFSTWC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE TUCSON AZ
804 PM MST WED AUG 31 2011

AZC021-010311-
/O.EXP.KTWC.FF.W.0056.000000T0000Z-110901T0300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
PINAL AZ-
804 PM MST WED AUG 31 2011

...THE FLASH FLOOD WARNING HAS EXPIRED FOR SOUTHEASTERN PINAL
COUNTY...

EARLIER THIS EVENING SHOWERS AND THUNDERSTORMS PRODUCED VERY HEAVY 
RAIN FROM CAMPO BONITO TO SAN MANUEL. ONE OF OUR TRAINED WEATHER 
SPOTTERS IN THE AREA RECEIVED 3.5 INCHES OF RAIN WITH THIS STORM. 
SINCE THAT TIME THE RAIN HAS ENDED...BUT THE WASHES ON THE NORTH AND 
EAST SIDE OF THE SANTA CATALINA MOUNTAINS IN PINAL COUNTY WILL 
CONTINUE TO FLOW THROUGH THE REMAINDER OF THE EVENING HOURS.   

LAT...LON 3267 11072 3273 11053 3252 11057 3252 11081

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 31, 5:41 PM MST	Special Weather Statement	TWC	Pinal	49 min
Aug 31, 5:49 PM MST	Areal Flood Advisory	TWC	Cochise, Graham	86 min
Aug 31, 5:56 PM MST	Areal Flood Advisory	TWC	Pima, Pinal	79 min
Sep 1, 2:56 PM MST	Areal Flood Advisory	TWC	Graham	74 min
Sep 1, 4:13 PM MST	Special Weather Statement	TWC	Santa Cruz	47 min
Sep 1, 4:39 PM MST	Areal Flood Advisory	TWC	Cochise	51 min
Sep 1, 4:52 PM MST	Areal Flood Advisory	TWC	Pima, Pinal	101 min

Nearby

Flash Flood Warnings in Arizona, 2011 Every flash flood warning in 2011

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.