Alert archive / Arizona / Flash Flood Warnings in 2011

Flash Flood Warning 48, NWS Tucson, AZ

August 18, 2011Pima County, Arizona

NWS Tucson, AZ issued this flash flood warning at Aug 18, 2011, 4:20 PM MST for Pima County, Arizona. It was in force for 85 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 18, 2011, 4:20 PM MST (23:20 UTC)
Expired
Aug 18, 2011, 5:45 PM MST
In force
85 min
Issued by
NWS Tucson, AZ
Area
Storm-based polygon
Flood severity
None

County Pima County, AZ

The radar

The Tucson radar (KEMX), 52 km from the middle of the area, began a volume at 23:20 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.

What was reported inside it

TimeReportWhereRemark
Aug 18, 5:10 PM MSTFLASH FLOOD6 Se Sabino Canyon, AZSWIFT WATER RESCUE. ONE MOTORIST IN CAR WITH WATER UP TO ROOF NEAR FORT LOWELL ROAD AND MELPOMENE WAY.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Tuscon, AZ (KTUS), launched 12:00Z, 11.3 hours before the alert went out and 26 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, Tuscon, AZ at 12:00Z on 2011-08-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1103 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Tuscon, AZ at 12:00Z on 2011-08-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -15 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
1103 J/kg
Mixed-layer CIN
-59 J/kg
Mixed-layer LCL
1836 m above ground
0-6 km bulk shear
4 kt
0-1 km storm-relative helicity
-15 m²/s²
0-3 km storm-relative helicity
85 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.

326 
WGUS55 KTWC 182320
FFWTWC
AZC019-190045-
/O.NEW.KTWC.FF.W.0048.110818T2320Z-110819T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE TUCSON AZ
420 PM MST THU AUG 18 2011

THE NATIONAL WEATHER SERVICE IN TUCSON HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHEASTERN PIMA COUNTY IN SOUTH CENTRAL ARIZONA...

* UNTIL 545 PM MST

* AT 412 PM MST...DOPPLER RADAR INDICATED VERY HEAVY RAIN ON THE FAR 
  NORTHEAST SIDE OF TUCSON INCLUDING THE REDINGTON PASS AREA. 
  DOPPLER RADAR ESTIMATED RAINFALL AND NEARBY GAUGES REPORT THAT ONE 
  TO ONE AND A HALF INCHES OF RAIN HAS FALLEN IN THIS AREA IN 
  THE PAST HALF HOUR.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL 
CREEKS AND STREAMS...HIGHWAYS AND UNDERPASSES. 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 3243 11085 3246 11055 3225 11056 3221 11086

$$
2 follow-up statements
030 
WGUS75 KTWC 182351
FFSTWC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE TUCSON AZ
451 PM MST THU AUG 18 2011

AZC019-190045-
/O.CON.KTWC.FF.W.0048.000000T0000Z-110819T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
PIMA AZ-
451 PM MST THU AUG 18 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 545 PM MST FOR
NORTHEASTERN PIMA COUNTY...

AT 442 PM MST...MODERATE TO LOCALLY HEAVY RAIN CONTINUES TO FALL 
OVER NORTHEAST PORTIONS OF THE TUCSON METRO AREA. DOPPLER RADAR 
INDICATED THAT UP TO ONE AND A HALF INCHES OF RAIN HAD FALLEN IN THE 
WARNED AREA...WHICH INCLUDES REDINGTON PASS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL 
CREEKS AND STREAMS AND OTHER LOW LYING AREAS.

&&

LAT...LON 3243 11085 3246 11055 3225 11056 3221 11086

$$
690 
WGUS75 KTWC 190048
FFSTWC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE TUCSON AZ
548 PM MST THU AUG 18 2011

AZC019-190057-
/O.EXP.KTWC.FF.W.0048.000000T0000Z-110819T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
PIMA AZ-
548 PM MST THU AUG 18 2011

...THE FLASH FLOOD WARNING HAS EXPIRED FOR NORTHEASTERN PIMA
COUNTY...

PERIODS OF MODERATE RAIN WILL CONTINUE THROUGH 7 PM. A URBAN AND 
SMALL STREAM FLOOD ADVISORY IS IN EFFECT UNTIL 830 PM FOR ALL OF 
EASTERN PIMA COUNTY.

LAT...LON 3243 11085 3246 11055 3225 11056 3221 11086

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 17, 5:15 PM MSTFlash Flood WarningTWCCochise90 min
Aug 17, 5:28 PM MSTSevere Thunderstorm WarningTWCCochise32 min
Aug 18, 11:27 AM MSTAreal Flood AdvisoryTWCCochise78 min
Aug 18, 12:34 PM MSTSpecial Weather StatementTWCGraham41 min
Aug 18, 12:44 PM MSTSpecial Weather StatementTWCPinal46 min
Aug 18, 1:03 PM MSTSevere Thunderstorm WarningTWCPinal42 min
Aug 18, 1:31 PM MSTSevere Thunderstorm WarningTWCCochise, Pima44 min
Aug 18, 1:34 PM MSTSevere Thunderstorm WarningTWCSanta Cruz26 min
Aug 18, 2:03 PM MSTSevere Thunderstorm WarningTWCSanta Cruz27 min
Aug 18, 2:14 PM MSTSevere Thunderstorm WarningTWCCochise46 min
Aug 18, 2:15 PM MSTSevere Thunderstorm WarningTWCCochise, Graham45 min
Aug 18, 2:21 PM MSTSevere Thunderstorm WarningTWCPima39 min
Aug 18, 3:18 PM MSTAreal Flood AdvisoryTWCPinal3 hr
Aug 18, 3:19 PM MSTAreal Flood AdvisoryTWCPima, Santa Cruz116 min
Aug 18, 3:29 PM MSTAreal Flood AdvisoryTWCPima2 hr
Aug 18, 3:59 PM MSTSevere Thunderstorm WarningTWCPima46 min
Aug 18, 4:39 PM MSTFlash Flood WarningTWCCochise81 min

Nearby

Flash Flood Warnings in Arizona, 2011Every 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.