Alert archive / Arizona / Flash Flood Warnings in 1999

Flash Flood Warning 9, NWS Tucson, AZ

July 9, 1999Pima County, Arizona

NWS Tucson, AZ issued this flash flood warning at Jul 9, 1999, 12:13 PM MST for Pima County, Arizona. It was in force for 62 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jul 9, 1999, 12:13 PM MST (19:13 UTC)
Expired
Jul 9, 1999, 1:15 PM MST
In force
62 min
Issued by
NWS Tucson, AZ
Area
Whole counties

County Pima County, AZ

The radar

The Tucson radar (KEMX), 112 km from the middle of the area, began a volume at 19:12 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, 7.2 hours before the alert went out and 84 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 1999-07-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 505 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 1999-07-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -32 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
505 J/kg
Mixed-layer CIN
-101 J/kg
Mixed-layer LCL
1091 m above ground
0-6 km bulk shear
5 kt
0-1 km storm-relative helicity
-32 m²/s²
0-3 km storm-relative helicity
34 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 KTUS 091911
FFWTUS
AZC019-092015-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE TUCSON AZ
1213 PM MST FRI JUL 9 1999

THE NATIONAL WEATHER SERVICE IN TUCSON HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CENTRAL PIMA COUNTY IN SOUTHERN ARIZONA
  INCLUDING SELLS IN THE TOHONO OODHAM NATION

* UNTIL 115 PM MST

* AT 1205 PM MST... NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  A THUNDERSTORM WITH VERY HEAVY RAIN NEAR SELLS. THE STORM WAS
  NEARLY STATIONARY.

* RADAR ESTIMATES THAT 2 INCHES OF RAIN HAS FALLEN IN ONLY 20
  MINUTES JUST NORTHEAST OF SELLS...WITH MUCH OF THE RUNOFF
  HEADING TOWARD SELLS WASH. UP TO 3 INCHES OF RAIN IS LIKELY JUST
  NORTHEAST OF SELLS TH~ROUGH 1245 PM.

A SEVERE THUNDERSTORM WARNING IS ALSO IN EFFECT UNTIL 1220 PM FOR
WIND GUSTS TO 60 MPH AND UP TO ONE INCH DIAMETER HAIL.

PYTLAK

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 Jul 9, 9:20 AM MST, 2 hours 53 minutes earlier.

Area forecast discussion, Jul 9, 9:20 AM MST, 2 hours 53 minutes before
SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
920 AM MST FRI JUL 9 1999

SYNOPSIS...HIGH PRESSURE OVER THE FOUR CORNERS WILL KEEP SOUTHERN
ARIZONA IN A PERSISTENT MONSOON FLOW THROUGH EARLY NEXT WEEK.
SCATTERED MAINLY AFTERNOON AND EVENING THUNDERSTORMS...SOME WITH
HEAVY RAINFALL AND STRONG WINDS ARE EXPECTED. ONE DISTURBANCE
PUSHING WESTWARD ACROSS NORTHERN MEXICO...AND ANOTHER ROTATING
AROUND THE HIGH INTO NORTHERN NEW MEXICO...MAY ENHANCE THE
THUNDERSTORM ACTIVITY THIS WEEKEND.

DISCUSSION...NOT AN EASY FORECAST FOR THIS AFTERNOON/EVENING. FLOW
PATTERNS EVEN WEAKER THAN YESTERDAY, BUT INSTABILITY IS STRONGER
WITH MODIFIED SOUNDINGS GIVING US CAPES AROUND 1500J/KG THIS
AFTERNOON. SOUNDING HAS ALSO MOISTUED UP A BIT WITH PRECIP WATER
LOOPS SHOWING A RATHER DEEP INFLUX INTO THE WESTERN DESERTS, PERHAPS
AS HIGH AS 1.75". MODELS ARE NOT PICKING UP ON THE CIRCULATION OVER
THE SOUTHERN GULF OF CALIFORNIA WHICH IS INDUCING SE FLOW UP THE
GULF AND INTO THE LOWER DESERTS. HERMOSILLO DEWPOINT HAS JUMPED 8F
IN JUST 2 HOURS. CU/ISOLATED TOWERING CU IS BREAKING OUT OVER MOST
OF NORTHERN SONORA PROVINCE AND ON A COUPLE OF MOUNTAINS AROUND
TUCSON. WITH SUCH WEAK FLOW, THINK THE STORMS WILL BEHAVE A LOT LIKE
YESTERDAY: HUGGING THE MOUNTAINS UNTIL LATE IN THE AFTERNOON,
FOLLOWED BY RATHER SPOTTY BUT VERY WET, SLOW-MOVING CELLS IN THE
DESERTS AND VALLEYS TONIGHT. WE'LL ADJUST FORECAST WORDING
ACCORDINGLY.

INCOMING MODELS ARE HIGHLY DIVEREGENT ON LARGE SCALE CIRCULATION
SATURDAY INTO SUNDAY. ETA TAKES THE WEAK SECONDARY ANTICYCLONIC
CIRCULATION OVER SW NEW MEXICO, STRENGTHENS IT, AND DRIFTS IT INTO
SE AZ. IF THAT HAPPENS, ALL BUT THE WESTERN DESERTS WOULD HAVE A
LOW-GRADE DAY SATURDAY, FOLLOWED BY A BIG DAY ON SUNDAY. THE NGM,
THOUGH, SQUASHES THE CICULATION AND OPENS THE DOOR FOR SEVERAL WAVES
TO MARCH ACROSS, WITH THE 1ST AS EARLY AS SATURDAY AFTERNOON. NOT
SURE IF EITHER SCENARIO (OR A COMBINATION OF THE TWO) IS CORRECT,
ESPECIALLY WITH THE PLAINS FRONTAL BOUNDARY SAGGING SOUTH AND
POSSIBLY BACKDORRING INTO NM. WATER VAPOR TRENDS ALONG WITH NEW AVN
GUIDANCE WILL FIGURE PROMINENTLY ON WHAT WE DO ABOUT POPS vAND
WORDING FOR LATER PERIODS. PYTLAK

.TWC...NONE.

In the hours before

Special weather statement, Jul 9, 10:35 AM MST, 1 hour 38 minutes before
AZZ019-029>035-100500-

SPECIAL WEATHER STATEMENT...SOUTHEAST ARIZONA CONVECTIVE OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1035 AM MST FRI JUL 9 1999...THIS PRODUCT IS NOT UPDATED

                          *CONDITIONAL*   *CONDITIONAL*
COUNTY            AREAL    PROBABILITY  RAIN GREATER THAN   STORM
                 COVERAGE   OF SEVERE     1.00      2.00    MOTION

COCHISE             50          10         30        20     NW 4
GRAHAM              50          10         30        20     NW 4
GREENLEE            60          10         35        20     VRBL 5
TUCSON/ERN PIMA     45          15         35        20     NW 5
TOHONO OODHAM      40          20         35        25     NW 5
SOUTHEAST PINAL     35          15         30        20     NW 5
WESTERN PIMA        35          20         35        25     NW 6
SANTA CRUZ          60          10         40        20     NW 5

SYNOPSIS...ATMOSPHERIC CONDITIONS ARE WETTER AND MORE UNSTABLE
THAN YESTERDSAY. HOWEVER...THE MEAN FLOW PATTERN IS ALSO WEAKER
AND BECOMING VARIABLE NEAR THE WHITE MOUNTAINS. THUS...ANY STORMS
THAT DEVELOP TODAY WILL HAVE TO BE MONITORED FOR FLASH FLOODING...
ESPECIALLY OVER PIMA...SANTA CRUZ...AND SOUTHERN COCHISE COUNTY
WHERE THE RAIN HAS BEEN HEAVIEST OVER THE PAST COUPLE OF DAYS.
THE STORMS WILL TEND TO REMAIN NEAR THE MOUNTAINS AT FIRST...BUT
SEVERAL OF THEM WILL DRIFT INTO THE VALLEYS ONCE THE ATMOSPHERE
HEATS UP COMPLETELY. AN ISOLATED DMAAGING DOWNBURST ALSO CANNOT
BE RULED OUT.

*****************************************************************
KEY...
AREAL COVERAGE - PERCENT OF COUNTY OR AREA THAT WILL EXPERIENCE
                 THUNDERSTORMS
PROB OF SEVERE - THE PROBABILITY THAT AN INDIVIDUAL STORM WILL
                 REACH SEVERE LEVELS (DAMAGING WIND AND/OR
                 LARGE HAIL)
RAIN GRTR THAN - THE PROBABILITY THAT AN INDIVIDUAL STORM WILL
                 PRODUCE RAIN EXCEEDING 1 INCH OR 2 INCHES IN
                 ANY LOCATION
STORM MOTION   - GENERAL DIRECTION TO WHICH THE STORMS WILL
                 LIKELY MOVE AND SPEED IN MPH

NOTE...
VALID TIME IS FROM 12:45 PM TO 12 MIDNIGHT OF THE DAY OF ISSUANCE.
THIS PRODUCT IS NOT TO BE USED IN PLACE OF SEVERE THUNDERSTORM OR
FLASH FLOOD WARNINGS OR WATCHES. THIS PRODUCT IS ONLY USED FOR
OUTLOOK PURPOSES. CORRESPONDING GRAPHICS MAY BE FOUND ON THE NWS
TUCSON INTERNET PAGE AT
HTTP://NIMBO.WRH.NOAA.GOV/TUCSON/SWO/SWO.SHTML

END/PYTLAK
Special weather statement, Jul 9, 10:35 AM MST, 1 hour 38 minutes before
AZZ019-029>035-100500-

SPECIAL WEATHER STATEMENT...SOUTHEAST ARIZONA CONVECTIVE OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1035 AM MST FRI JUL 9 1999...THIS PRODUCT IS NOT UPDATED

                          *CONDITIONAL*   *CONDITIONAL*
COUNTY            AREAL    PROBABILITY  RAIN GREATER THAN   STORM
                 COVERAGE   OF SEVERE     1.00      2.00    MOTION

COCHISE             50          10         30        20     NW 4
GRAHAM              50          10         30        20     NW 4
GREENLEE            60          10         35        20     VRBL 5
TUCSON/ERN PIMA     45          15         35        20     NW 5
TOHONO OODHAM      40          20         35        25     NW 5
SOUTHEAST PINAL     35          15         30        20     NW 5
WESTERN PIMA        35          20         35        25     NW 6
SANTA CRUZ          60          10         40        20     NW 5

SYNOPSIS...ATMOSPHERIC CONDITIONS ARE WETTER AND MORE UNSTABLE
THAN YESTERDSAY. HOWEVER...THE MEAN FLOW PATTERN IS ALSO WEAKER
AND BECOMING VARIABLE NEAR THE WHITE MOUNTAINS. THUS...ANY STORMS
THAT DEVELOP TODAY WILL HAVE TO BE MONITORED FOR FLASH FLOODING...
ESPECIALLY OVER PIMA...SANTA CRUZ...AND SOUTHERN COCHISE COUNTY
WHERE THE RAIN HAS BEEN HEAVIEST OVER THE PAST COUPLE OF DAYS.
THE STORMS WILL TEND TO REMAIN NEAR THE MOUNTAINS AT FIRST...BUT
SEVERAL OF THEM WILL DRIFT INTO THE VALLEYS ONCE THE ATMOSPHERE
HEATS UP COMPLETELY. AN ISOLATED DMAAGING DOWNBURST ALSO CANNOT
BE RULED OUT.

*****************************************************************
KEY...
AREAL COVERAGE - PERCENT OF COUNTY OR AREA THAT WILL EXPERIENCE
                 THUNDERSTORMS
PROB OF SEVERE - THE PROBABILITY THAT AN INDIVIDUAL STORM WILL
                 REACH SEVERE LEVELS (DAMAGING WIND AND/OR
                 LARGE HAIL)
RAIN GRTR THAN - THE PROBABILITY THAT AN INDIVIDUAL STORM WILL
                 PRODUCE RAIN EXCEEDING 1 INCH OR 2 INCHES IN
                 ANY LOCATION
STORM MOTION   - GENERAL DIRECTION TO WHICH THE STORMS WILL
                 LIKELY MOVE AND SPEED IN MPH

NOTE...
VALID TIME IS FROM 12:45 PM TO 12 MIDNIGHT OF THE DAY OF ISSUANCE.
THIS PRODUCT IS NOT TO BE USED IN PLACE OF SEVERE THUNDERSTORM OR
FLASH FLOOD WARNINGS OR WATCHES. THIS PRODUCT IS ONLY USED FOR
OUTLOOK PURPOSES. CORRESPONDING GRAPHICS MAY BE FOUND ON THE NWS
TUCSON INTERNET PAGE AT
HTTP://NIMBO.WRH.NOAA.GOV/TUCSON/SWO/SWO.SHTML

END/PYTLAK

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 8, 9:37 PM MSTSevere Thunderstorm WarningTWCPima43 min
Jul 8, 9:55 PM MSTFlash Flood WarningTWCPima60 min
Jul 8, 10:51 PM MSTFlash Flood WarningTWCPima44 min
Jul 9, 11:09 AM MSTSevere Thunderstorm WarningTWCPima31 min
Jul 9, 11:50 AM MSTSevere Thunderstorm WarningTWCPima30 min
Jul 9, 12:46 PM MSTSevere Thunderstorm WarningTWCSanta Cruz49 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.