Alert archive / Arizona / Flash Flood Warnings in 2008

Flash Flood Warning 59, NWS Tucson, AZ

August 7, 2008Pima County, Arizona

NWS Tucson, AZ issued this flash flood warning at Aug 7, 2008, 4:45 PM MST for Pima County, Arizona. It was in force for 2 hr. 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 7, 2008, 4:45 PM MST (23:45 UTC)
Expired: Aug 7, 2008, 6:45 PM MST
In force: 2 hr
Issued by: NWS Tucson, AZ
Area: Storm-based polygon
Flood severity: None

County Pima County, AZ

The radar

The Tucson radar (KEMX), 92 km from the middle of the area, began a volume at 23:47 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this flash flood warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Tuscon, AZ (KTUS), launched 12:00Z, 11.8 hours before the alert went out and 57 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: 847 J/kg
Mixed-layer CIN: -50 J/kg
Mixed-layer LCL: 1884 m above ground
0-6 km bulk shear: 5 kt
0-1 km storm-relative helicity: -11 m²/s²
0-3 km storm-relative helicity: -14 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 072345
FFWTWC
AZC019-080145-
/O.NEW.KTWC.FF.W.0059.080807T2345Z-080808T0145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE TUCSON AZ
445 PM MST THU AUG 7 2008

THE NATIONAL WEATHER SERVICE IN TUCSON HAS ISSUED A

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

* UNTIL 645 PM MST

* AT 438 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS PRODUCING VERY HEAVY 
RAINFALL. MOVEMENT OF THESE SHOWERS AND THUNDERSTORMS WAS TO THE 
NORTHWEST AT 5 MPH. DOPPLER RADAR RAINFALL ESTIMATES OF 2 TO 3 
INCHES HAVE FALLEN DURING THE PAST HOUR.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO SILVER 
  BELL...AVRA VALLEY...AND QUEENS WELL.

LAT...LON 3223 11125 3206 11127 3212 11157 3225 11163
      3229 11165 3236 11168 3251 11175 3251 11147
      3236 11133

$$

2 follow-up statements

000 
WGUS75 KTWC 080101
FFSTWC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE TUCSON AZ
601 PM MST THU AUG 7 2008

AZC019-080145-
/O.CON.KTWC.FF.W.0059.000000T0000Z-080808T0145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
PIMA AZ-
601 PM MST THU AUG 7 2008

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 645 PM MST FOR
CENTRAL PIMA COUNTY...

AT 551 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS PRODUCING MODERATE 
TO HEAVY RAINFALL OVER CENTRAL PIMA COUNTY. MOVEMENT WAS TO THE WEST 
AT 5 MPH. DOPPLER RADAR RAINFALL ESTIMATES OF 1 TO 2 INCHES HAVE 
FALLEN OVER THE WARNED AREA DURING THE PAST HOUR. SEVERAL LOW WATER 
CROSSINGS ARE LIKELY IMPACTED WITH FLOWING WATER.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO SILVER BELL.

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. MOVE TO HIGHER GROUND.

LAT...LON 3223 11125 3206 11127 3212 11157 3225 11163
      3229 11165 3236 11168 3251 11175 3251 11147
      3236 11133

$$

000 
WGUS75 KTWC 080144
FFSTWC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE TUCSON AZ
644 PM MST THU AUG 7 2008

AZC019-080153-
/O.EXP.KTWC.FF.W.0059.000000T0000Z-080808T0145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
PIMA AZ-
644 PM MST THU AUG 7 2008

...THE FLASH FLOOD WARNING WILL EXPIRE AT 645 PM MST FOR CENTRAL PIMA
COUNTY...

AT 642 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
THAT ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS PRODUCING 
MOSTLY LIGHT RAINFALL OVER CENTRAL PIMA COUNTY...INCLUDING THE AVRA 
VALLEY AREA. THUS THE FLASH FLOOD WARNING WILL EXPIRE AT 645 PM MST. 
A CHANCE OF SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS THE AREA 
TONIGHT.

LAT...LON 3223 11125 3206 11127 3212 11157 3225 11163
      3229 11165 3236 11168 3251 11175 3251 11147
      3236 11133

$$

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 7, 2:00 PM MST, 2 hours 45 minutes earlier.

Area forecast discussion, Aug 7, 2:00 PM MST, 2 hours 45 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
200 PM MST THU AUG 7 2008

.SYNOPSIS...FAVORABLE CONDITIONS FOR STRONG THUNDERSTORM DEVELOPMENT
TODAY AND TONIGHT...OTHERWISE SUFFICIENT MOISTURE WILL REMAIN OVER
THE AREA FOR A DAILY CHANCE OF SHOWERS AND THUNDERSTORMS INTO NEXT
WEEK.

&&

.DISCUSSION...STRONG CONVECTIVE DEVELOPMENT THIS AFTERNOON WITH LOW
LEVEL MOISTURE CONVERGENCE...DECENT INSTABILITY AND SHEAR. AS STATED
THIS MORNING DURING THE UPDATE...ORGANIZED CONVECTION INITIALLY NEAR
THE BORDER THAT SPREADS INTO MUCH OF SANTA CRUZ AND EASTERN PIMA
COUNTIES AND SUBSEQUENTLY THE TOHONO OODHAM NATION DURING AFTERNOON
AND EVENING HOURS. ISOLATED ACTION KICKING IN FOR SOUTHEAST PINAL
AND GRAHAM COUNTIES AS WELL. MID SHIFT HAD A NICE TREND SHOWING
THIS...WE PUT OUT A MORNING UPDATE TO TWEAK AND EMPHASIZE THIS A BIT
MORE. ALSO HWO OUT FOR STRONGER STORMS TODAY. CONCERN INCLUDES BOTH
SEVERE AND FLASH FLOOD POTENTIAL.

IF WE DO GO OFF OVER A WIDE ENOUGH AREA TODAY AND TONIGHT (WHICH IS
STARTING TO BE THE CASE)...THE FLOW IS NOT SUCH TO RESET RIGHT
AWAY...SO WOULD SEE SOMEWHAT OF A DOWN DAY FRIDAY. IF WE DONT HAVE
WIDESPREAD ENOUGH CONVECTION THEN FRIDAY SHOULD BE A STRONG
THUNDERSTORM DAY. OTHERWISE SHOULD BE A GOOD WEEKEND FOR STORMS WITH
A STANDARD FORECAST TO START THE WEEK AS SUFFICIENT MOISTURE AND
INSTABILITY HANG IN FOR TYPICAL EARLY AUGUST WEATHER.

&&

.AVIATION...SCATTERED THUNDERSTORMS THIS AFTERNOON AND EVENING WITH
LOCALLY HEAVY RAINFALL AND STRONG OUTFLOWS. AVIATION DISCUSSION NOT
UPDATED FOR TAF AMENDMENTS.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

WEATHER.GOV/TUCSON

Hazardous weather outlook, Aug 7, 8:23 AM MST, 8 hours 22 minutes before

HAZARDOUS WEATHER OUTLOOK...CORRECTION
NATIONAL WEATHER SERVICE TUCSON AZ
823 AM MST THU AUG 7 2008

AZZ019-029>035-080700-
NORTHERN GREENLEE COUNTY-SOUTHEAST PINAL COUNTY-
UPPER GILA RIVER VALLEY-WESTERN PIMA COUNTY-TOHONO OODHAM NATION-
TUCSON METRO/MARANA/GREEN VALLEY-SANTA CRUZ COUNTY-COCHISE COUNTY-
823 AM MST THU AUG 7 2008

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTH CENTRAL
ARIZONA AND SOUTHEAST ARIZONA.

.DAY ONE...TODAY AND TONIGHT

THE RISK HAS INCREASED FOR A FEW SEVERE THUNDERSTORMS THIS AFTERNOON
AND EVENING AS AN UPPER LEVEL DISTURBANCE MOVES WEST ACROSS
CHIHUAHUA MEXICO. THIS DISTURBANCE HAS ALREADY BEGUN TO DESTABILIZE
THE ATMOSPHERE...AND COMBINED WITH EAST WINDS OF 10 TO 15 MPH
ALOFT...THE STORMS TODAY WILL TEND TO ORGANIZE INTO CLUSTERS OR
LINES.

SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER THE MOUNTAINS
OF SOUTHEAST ARIZONA AFTER 11 AM...ESPECIALLY OVER SANTA CRUZ AND
COCHISE COUNTIES. THESE WILL THEN INCREASE IN COVERAGE AND INTENSITY
AS THEY MOVE WEST INTO THE VALLEYS AND DESERTS LATE THIS AFTERNOON
AND EVENING. THE STRONGEST STORMS WILL BE CAPABLE OF PRODUCING
DAMAGING WINDS IN EXCESS OF 60 MPH...HAIL UP TO ONE INCH IN
DIAMETER...1 TO 2 INCHES OF RAIN...AND FREQUENT LIGHTNING. THE MAIN
THREAT FOR SEVERE WEATHER WILL BE FROM AROUND 1 PM UNTIL AROUND 10
PM...BUT A FEW THUNDERSTORMS COULD LINGER OVER THE WESTERN DESERTS
INTO THE OVERNIGHT HOURS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

AN ACTIVE MONSOON FLOW PATTERN WILL CONTINUE THROUGH THE UPCOMING
WEEKEND AS A SERIES OF DISTURBANCES MOVE WEST ACROSS NORTHERN MEXICO
AND SOUTHERN ARIZONA. IT IS DIFFICULT TO DETERMINE WHICH DAYS WILL
BE MORE ACTIVE THAN OTHERS SINCE THERE WILL LIKELY BE AT LEAST SOME
RESIDUAL CLOUD COVER EACH MORNING WHICH MAY REDUCE DAYTIME HEATING
AND INSTABILITY. HOWEVER ANY THUNDERSTORMS THAT DEVELOP THIS WEEKEND
WILL POSE A HEAVY RAIN THREAT AS EVEN MORE MOISTURE SPREADS NORTH
FROM THE GULF OF CALIFORNIA.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

PYTLAK
CORRECTED TYPO IN DAYS TWO THROUGH SEVEN SECTION

WEATHER.GOV/TUCSON

In the hours before

Local storm report, Aug 7, 1:37 PM MST, 3 hours 8 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TUCSON AZ
137 PM MST THU AUG 07 2008

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0345 PM     TSTM WND DMG     10 E TUCSON             32.24N 110.77W
08/06/2008                   PIMA               AZ   NWS EMPLOYEE

            2 LARGE TREE LIMBS DOWN...4-5 FEET LONG ABOUT 6 INCHES IN
            DIAMETER

&&

JMEYER

Local storm report, Aug 7, 3:55 PM MST, 50 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TUCSON AZ
355 PM MST THU AUG 07 2008

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0353 PM     FLASH FLOOD      SIERRA VISTA            31.55N 110.29W
08/07/2008                   COCHISE            AZ   TRAINED SPOTTER

            TRAINED SPOTTER REPORTED STREETS FLOODED IN SIERRA VISTA.
            0.75 INCH RAINFALL IN 15 MINUTES.

&&

BTURNER

Local storm report, Aug 7, 4:33 PM MST, 12 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TUCSON AZ
433 PM MST THU AUG 07 2008

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0342 PM     FLASH FLOOD      NOGALES                 31.36N 110.93W
08/07/2008                   SANTA CRUZ         AZ   LAW ENFORCEMENT

            7 FOOT RISE ON NOGALES WASH IN DOWNTOWN NOGALES

&&

PYTLAK

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 6, 5:24 PM MST	Areal Flood Advisory	TWC	Pima	81 min
Aug 6, 5:30 PM MST	Areal Flood Advisory	TWC	Pima	31 min
Aug 6, 5:32 PM MST	Areal Flood Advisory	TWC	Santa Cruz	58 min
Aug 6, 5:58 PM MST	Flash Flood Warning	TWC	Pima	2 hr
Aug 6, 6:21 PM MST	Severe Thunderstorm Warning	TWC	Pima	39 min
Aug 7, 11:48 AM MST	Flash Flood Warning	TWC	Cochise	117 min
Aug 7, 2:12 PM MST	Severe Thunderstorm Warning	TWC	Pima, Santa Cruz	48 min
Aug 7, 2:19 PM MST	Flash Flood Warning	TWC	Pima, Santa Cruz	116 min
Aug 7, 2:31 PM MST	Severe Thunderstorm Warning	TWC	Pima	44 min
Aug 7, 3:01 PM MST	Severe Thunderstorm Warning	TWC	Pima	89 min
Aug 7, 3:05 PM MST	Flash Flood Warning	TWC	Santa Cruz	3 hr
Aug 7, 3:41 PM MST	Flash Flood Warning	TWC	Pima	2 hr
Aug 7, 3:46 PM MST	Flash Flood Warning	TWC	Cochise	119 min
Aug 7, 4:13 PM MST	Severe Thunderstorm Warning	TWC	Pinal	47 min
Aug 7, 4:23 PM MST	Areal Flood Advisory	TWC	Pima, Santa Cruz	2 hr
Aug 7, 4:54 PM MST	Severe Thunderstorm Warning	TWC	Pinal	21 min
Aug 7, 4:56 PM MST	Severe Thunderstorm Warning	TWC	Pinal	34 min

Nearby

Flash Flood Warnings in Arizona, 2008 Every flash flood warning in 2008

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.