Alert archive / Arizona / Flash Flood Warnings in 2001

Flash Flood Warning 21, NWS Tucson, AZ

July 31, 2001Pima County, Arizona

NWS Tucson, AZ issued this flash flood warning at Jul 31, 2001, 1:25 PM MST for Pima County, Arizona. It was in force for 5 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties.

The facts

Issued
Jul 31, 2001, 1:25 PM MST (20:25 UTC)
Expired
Jul 31, 2001, 1:30 PM MST
In force
5 min
Issued by
NWS Tucson, AZ
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Pima County, AZ

The radar

The Tucson radar (KEMX), 41 km from the middle of the area, began a volume at 20:26 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 12:00Z, 8.4 hours before the alert went out and 2 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 2001-07-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 473 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Tuscon, AZ at 12:00Z on 2001-07-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -6 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
473 J/kg
Mixed-layer CIN
-80 J/kg
Mixed-layer LCL
1545 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
-6 m²/s²
0-3 km storm-relative helicity
64 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 
WGUS55 KTWC 312029
FFWTWC
AZC019-312035-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE TUCSON AZ
125 PM MST TUE JUL 31 2001

THE NATIONAL WEATHER SERVICE IN TUCSON HAS EXTENDED THE

* FLASH FLOOD WARNING FOR...
  EASTERN PIMA COUNTY IN ARIZONA
  THIS INCLUDES...MARANA AND THE WEST SIDE OF TUCSON.

* UNTIL 230 PM MST

* AT 125 PM MST...WEATHER SERVICE DOPPLER RADAR CONTINUE TO SHOW
  A LINE OF HEAVY RAIN EXTENDING NORTH SOUTH JUST FROM MARANA
  SOUTH ACROSS THE TUCSON MOUNTAINS.

* THIS STORM IS GRADUALLY WORKING ITS WAY WAST INTO THE
  TOHONO OODHAM NATION.


NEW STORMS WILL CONTINUE TO DEVELOP ALONG AND WEST OF THIS LINE.
WASHES AND LOW WATER CROSSINGS WILL REMAIN FLOODED THROUGH 230 PM IN
MANY AREAS. THESE STORMS WERE PRODUCING UPWARDS OF 2 INCHES OF RAIN.

DUE TO THE HEAVY RAIN THAT HAS FALLEN...WASHES WILL CARY THIS WATER
FAR FROM WHERE THE RAIN FELL.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
DO NOT ATTEMPT TO CROSS SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN
DEPTH BY FOOT OR BY AUTOMOBILE.

LAT...LON 3193 11121 3194 11049 3252 11050 3251 11120

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 31, 12:05 PM MSTFlash Flood WarningTWCPima
Jul 31, 12:20 PM MSTSevere Thunderstorm WarningTWCPima40 min
Jul 31, 1:05 PM MSTFlash Flood WarningTWCPima24 hr
Jul 31, 1:40 PM MSTFlash Flood WarningTWCPinal

Nearby

Flash Flood Warnings in Arizona, 2001Every flash flood warning in 2001

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.