Alert archive / Arizona / Flash Flood Warnings in 1999

Flash Flood Warning 36, NWS Tucson, AZ

August 14, 1999Pima County, Arizona

NWS Tucson, AZ issued this flash flood warning at Aug 14, 1999, 7:31 PM MST for Pima County, Arizona. It was in force for 89 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
Aug 14, 1999, 7:31 PM MST (02:31 UTC)
Expired
Aug 14, 1999, 9:00 PM MST
In force
89 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), 29 km from the middle of the area, began a volume at 02:31 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, 2.5 hours before the alert went out and 42 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 00:00Z on 1999-08-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 89 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 00:00Z on 1999-08-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 79 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
89 J/kg
Mixed-layer CIN
-131 J/kg
Mixed-layer LCL
2402 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
79 m²/s²
0-3 km storm-relative helicity
119 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 
TTAA00 KTWC 150233
FFWTUS
AZC019-150400-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE TUCSON AZ
731 PM MST SAT AUG 14 1999

THE NATIONAL WEATHER SERVICE IN TUCSON HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHEASTERN PIMA COUNTY IN ARIZONA

* UNTIL 900 PM MST

* AT 729 PM MST...WEATHER SERVICE DOPPLER RADAR INDICATED VERY HEAVY 
RAIN OVER SOUTHEASTERN PIMA COUNTY...OR ABOUT 8 MILES EAST SOUTHEAST 
OF GREEN VALLEY...MOVING NORTHEAST AT 20 MPH. RADAR RAINFALL 
ESTIMATES INDICATED THAT UP TO 4 INCHES OF RAIN HAD FALLEN OVER THIS 
AREA.

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. IF YOUR VEHICLE STALLS, ABANDON IT IMMEDIATELY AND SEEK
HIGHER GROUND.

LAT...LON 3173 11102 3175 11083 3189 11076 3187 11096

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Tucson, AZ wrote its last area forecast discussion before this flash flood warning went out at Aug 14, 2:30 PM MST, 5 hours 1 minute earlier.

Area forecast discussion, Aug 14, 2:30 PM MST, 5 hours 1 minute before
SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
230 PM MST SAT AUG 14 1999

SYNOPSIS...SOUTHEAST FLOW AROUND A LARGE HIGH PRESSURE SYSTEM
CENTERED IN TEXAS WILL LEAD TO A CONTINUED THREAT OF AFTERNOON AND
EVENING THUNDERSTORMS INTO NEXT WEEK.

DISCUSSION...CLOUDS HAVE THINNED ENOUGH TO PRODUCE GOOD HEATING OVER
MUCH OF THE AREA THIS AFTERNOON. THE SONORA MEXICO CIRCULATION
SYSTEM IS APPROACHING THE AREA AND FIRING SOME CONVECTION. NGM ALSO
SHOWING A GOOD MID LEVEL THETA-E RIDGE THRU THE AREA THIS EVENING.
EXPECT THESE FEATURES TO BE THE MAIN THUNDERSTORM PRODUCERS THRU THE
EVENING. DUE TO RELATIVELY DRY LOWER LAYERS EXPECT SOME GUSTY WINDS
WITH THE THUNDERSTORMS. FLOODING LESS A THREAT WITH DRY LOWER LEVELS
AND STORMS WILL BE MOVING. ON SUNDAY NGM SHOWING A LOWER POTENTIAL DAY
WITH SOME DRYING AND THE THETA-E RIDGE FURTHER EAST. AT THIS TIME LOOKS
SUSPECT AND WILL CONTINUE WITH SCATTERED AFTERNOON AND EVENING WITH
POPS A NOTCH LOWER THAN TODAY. STRONG EASTERLY WAVE IN SOUTHEAST
MEXICO GETS CAUGHT UP IN THE CIRCULATION AROUND THE TEXAS HIGH AND IS
DRAWN INTO THE STATE BY MONDAY. IT IS SHOWING WEAKER AT THAT TIME BUT
SHOULD STILL HELP FOCUS THE THUNDERSTORMS. TIMING IS UNCERTAIN SO WILL
PUSH POPS UP FOR THE DAY. THE EXTENDED PORTION SHOWS THE HIGH RIDGE
AXIS SHIFTING NORTHWARD AND BECOMING A MORE 4 CORNERS HIGH...THUS
MONSOON THUNDERSTORMS TO CONTINUE. RVE

.TWC...NONE.

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 15, 3:17 PM MSTSevere Thunderstorm WarningTWCPima43 min

Nearby

Flash Flood Warnings in Arizona, 1999Every flash flood warning in 1999

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.