Flash Flood Warning 14, NWS Tucson, AZ

SOUTHEAST ARIZONA FORECAST DISCUSSION...CORRECTED SYNOPSIS
NATIONAL WEATHER SERVICE TUCSON AZ
237 PM MST WED JUL 25 2001

SYNOPSIS...A LOW PRESSURE SYSTEM NEAR LAS VEGAS WILL MOVE NORTHEAST
INTO UTAH ON THURSDAY. SOUTHWEST FLOW BEHIND THIS SYSTEM WILL BRING
PROGRESSIVELY DRIER AIR INTO THE REGION FOR THE REST OF THE WEEK.
MOISTURE MAY ONCE AGAIN INCREASE EARLY NEXT WEEK AS HIGH PRESSURE
ORGANIZES OVER NEW MEXICO.

DISCUSSION...SE AZ IS IN THE TAIL OF THE UPPER LOW LIFTING THROUGH
THE KVEF CWA. THE VORT TAIL EXTENDS TO JUST W OF KTUS AND SHOULD
CONTINUE TO BE THE FOCAL POINT FOR TSTMS TONIGHT. THINGS AROUND
NOONTIME LOOKED QUITE INTERESTING, BUT WARMING/CAPPING ALOFT IS
TAKING ITS TOLL, WITH NEW DEVELOPMENT FURTHER SW ALONG THE TAIL NEAR
KTUS BEING SQUASHED OUT. DEWPOINTS TOOK A PLUNGE ALONG THE CO RIVER
AROUND NOON, WHICH MEANS THE SURGE IS ALSO MIXING OUT AND POSSIBLY
SETTING UP A WEAK LOW LEVEL CONVERGENCE AXIS/PSEUDO DRYLINE FROM
JUST W OF KPHX-W OF SELLS. IF THIS WARMING ALOFT ISN'T OVERCOME
SOON, THOUGH, TSTMS COVERAGE AND STRENGTH WILL BE WAY DOWN FROM WHAT
I EXPECTED EARLIER, ESPECIALLY S AND W OF KTUS. FURTHER E, THE
RIGHT-REAR QUAD OF A 70KT UPPER JET WILL EVENTUALLY INTERACT WITH
THE MONSOON MOISTURE AXIS AS 500MB S FLOW INCREASES TO AROUND 20KTS.
THE WARMING ALOFT SHOULD KEEP HEAVY RAINS RATHER ISOLATED, BUT THE
POTENTIAL FOR TRAINING IS THERE AND WILL HAVE TO BE WATCHED. WE'LL
MOST LIKELY DO SOME LAST-MINUTE WORDING CHANGES BEFORE PRESS TIME AS
WE SEE IF THIS WARMING ALOFT MERELY DELAYS ADDITIONAL DEVELOPMENT,
OR CHOKES IT OFF. EVEN WITH THE WARMING ALOFT, I'M STILL INCLINED,
GIVEN THE INCREASING MID LEVEL FLOW, TO HOLD ONTO AT A FEW SHOWERS
OVERNIGHT AND NOT SHUT THINGS DOWN COMPLETELY.

LONGWAVE PATTERN CONTINUES TO BE PRETTY DEPRESSING IF YOU WANT TO
SEE A WELL-ORGANIZED MONSOON PATTERN. THE WEST COAST TROUGH IS WELL
ANCHORED IN A STABLE 4 WAVE PATTERN. THAT WILL TEND TO KEEP MUCH OF
AZ IN DRY SW FLOW, ESPECIALLY AS INDIVIDUAL SHORT WAVES DROP INTO
THE BASE OF THE TROUGH AND SWEEP ACROSS THE GREAT BASIN. THIS LATEST
SHORT WAVE CAME PRETTY FAR S AND SHOULD SCOUR MOST OF THE CWA OUT BY
FRI. THE LONE EXCEPTION MAY BE IN THE EXTREME SE WHICH WILL REMAIN
NEAR THE UPPER LEVEL SHEAR AXIS. THERE ARE AT LEAST 2 EASTERLY WAVES
UNDERNEATH THE RIDGE MOVING W, BOTH OF WHICH COULD START ANOTHER
SURGE GOING IF THEY DON'T SHEAR OUT AS THE APPROACH AZ. BECAUSE OF
THESE WAVES, I'M ONLY GOING TO BACK US DOWN TO UNCERTAINTY WORDING
FOR THE WEEKEND AND NOT YANK TSTMS ENTIRELY. AVN/MRF CONTINUE TO
ADVERTISE AT LEAST SOME DEAMPLIFICATION IN THE LONGWAVE EARLY NEXT
WEEK, BUT MY CONFIDENCE ISN'T ALL THAT HIGH UNTIL WE SEE A
FUNDAMENTAL PATTERN CHANGE, AND I DON'T SEE ONE THROUGH AT LEAST DAY
10. IF NOTHING ELSE, HAVING A TROUGH TO OUR W WILL KEEP TEMPS PRETTY
CLOSE TO NORMAL AND NOT PARTICULARLY HOT. PYTLZAK

.TWC...NONE.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TUCSON ARIZONA
0958 AM MST WED JUL 25 2001

TIME (MST) .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0600 PM    DOUGLAS                   AZ   FLASH FLOOD
07/24/01   COCHISE                        FLASH FLOOD. THUNDERSTORMS WITH
                                          HEAVY RAIN BEGAN ABOUT 5 PM.
                                          VISIBILITY REDUCED TO ABOUT 50
                                          FEET IN RAIN...LASTED ABOUT
                                          1-HOUR.  WATER FLOWED 16 INCHES
                                          DEEP ON G AVENUE IN DOWNTOWN AREA.
                                          BUSNESSES AND HOMES FLOODED. SOME
                                          HOMES EVACUATED. LIGHTNING DAMAGE
                                          TO TRANSFORMERS RESULTED IN POWER
                                          OUTAGES.  ONE MOBILE HOME TURNED
                                          OVER...TREES UPROOTED...POWER
                                          LINES UNDERMINED BY WATER AND
                                          DOWNED

AZZ019-029>035-250700-

SOUTHEAST ARIZONA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1145 MST TUE JUL 24 2001

.SYNOPSIS...THE LOW PRESSURE SYSTEM NEAR LAS VEGAS HAS PULLED
MONSOON MOISTURE INTO SOUTHEAST ARIZONA.  THUNDERSTORM ACTIVITY HAS
ALREADY DEVELOPED AND WILL CONTINUE INTO THE LATE AFTERNOON AND
EVENING HOURS.  THE SEVERE THUNDERSTORM AND FLASH FLOODING THREAT IS
ABOVE CLIMATOLOGY ACROSS THE ENTIRE COUNTY WARNING AREA.

.DISCUSSION...THE INFLUX OF MOISTURE FROM MEXICO IS EVIDENT FROM THE
INCREASE IN DEWPOINT TEMPERATURES ACROSS SOUTHEAST ARIZONA.  THIS
CAN ALSO BE SEEN IN INFRARED AND WATER VAPOR IMAGERY.  THUNDERSTORM
ACTIVITY IS ALREADY ERUPTING ALONG THE MID LEVEL DRY LINE...SEEN IN
WATER VAPOR IMAGERY.  THE 18Z TUS SOUNDING SHOWED WIND INCREASING 10
TO 15 KNOTS...2000 CAPE VALUE...AND A LIFTED INDEX OF MINUS 6.  THE
BEST CHANCE OF SEVERE THUNDERSTORMS WILL BE ALONG THIS MID LEVEL DRY
LINE...AN AREA FROM CENTRAL PIMA TO CENTRAL GRAHAM AND COCHISE
COUNTIES.  SO FOR THE LATE AFTERNOON AND EVENING ORGANIZED AND
STRONG CONVECTION IS POSSIBLE.

THE FLASH FLOOD THREAT WILL ALSO BE ABOVE CLIMATOLOGY ACROSS THE
COUNTY WARNING AREA...WITH THE BEST CHANCES EXTENDING FROM EASTERN
PIMA THROUGH THE EASTERN COUNTIES....THIS INCLUDES
COCHISE...GRAHAM...SANTA CRUZ...GREENLEE COUNTIES THROUGH THE LATER
EVENING HOURS. SOME CELL TRAINING COULD OCCUR AND SOME STORMS COULD
LINGER INTO THE OVERNIGHT.

STORM MOVEMENT WILL BE NORTHEAST 15 MPH.