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000
FXUS65 KPSR 290455
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
955 PM MST FRI AUG 28 2015

.SYNOPSIS...
STRONG HIGH PRESSURE ALOFT WILL KEEP HIGH TEMPERATURES WELL ABOVE
SEASONAL NORMALS THROUGH SATURDAY WITH HOTTER LOWER DESERTS REACHING
OR EXCEEDING 110. THERE WILL BE SUFFICIENT MOISTURE EAST OF THE LOWER
COLORADO RIVER TO SUPPORT ISOLATED TO SCATTERED AFTERNOON AND EVENING
THUNDERSTORMS THROUGH SUNDAY. STARTING MONDAY DRIER WESTERLY FLOW
ALOFT WILL PUSH THE MOISTURE OFF TO THE EAST LIMITING STORM CHANCES
PRIMARILY TO HIGHER TERRAIN AREAS TO THE EAST OF PHOENIX. THERE WILL
BE A GRADUAL COOLING TREND STARTING SUNDAY WITH CENTRAL DESERTS HIGH
TEMPERATURES DROPPING TO AROUND SEASONAL NORMALS BY THE MIDDLE OF
NEXT WEEK.

&&

.DISCUSSION...
STORM ACTIVITY HAS DISSIPATED THIS EVENING ACROSS ARIZONA AND
SOUTHEAST CALIFORNIA. ANTICIPATE THAT TO REMAIN THE CASE OVERNIGHT AS
LOWER LEVELS HAVE HAD SOME DRYING OVER A GOOD PORTION OF
ARIZONA PER 00Z SOUNDINGS...LESS SO OVER SOUTHWEST ARIZONA AND INTO
FAR SOUTHEAST CALIFORNIA. ALSO...SONORA IS FAIRLY QUIET AND NEAREST
LARGE ACTIVITY IS OVER EASTERN NEW MEXICO. THERE COULD BE A STRAY
ISOLATED STORM THANKS TO A LONG TRAVELED GRAVITY WAVE BUT
PROBABILITY TOO LOW TO HOLD ON TO POPS FOR THE OVERNIGHT PERIOD. OF
NOTE...THE LATEST HRRR DOES DEVELOP SOME ACTIVITY OVER SOUTHEAST
ARIZONA WITH SOME VERY ISOLATED STORMS MAKING THEIR WAY INTO SOUTH-
CENTRAL ARIZONA LATE TONIGHT. LOCAL HI-RES MODELS AND 00Z NCAR
ENSEMBLE ARE NOT REFLECTING THAT. LATEST NAM AND GFS INDICATE SOME
RECOVERY OF MOISTURE SATURDAY AND THUS MORE STORMS THAN
TODAY...MAINLY OVER SOUTHEAST ARIZONA. ALSO SOME SOUTHERLY MID LEVEL
WINDS WHICH SHOULD BRING STORMS CLOSER TO THE PHOENIX AREA THAN
TODAY. NO CHANGES TO CURRENT FORECASTS.

&&

.PREVIOUS DISCUSSION ISSUED 152 PM...
AS EXPECTED THERE HAS BEEN A LATER ONSET TO STORM ACTIVITY TODAY
WITH ONLY A FEW SHOWERS AND THUNDERSTORMS IN NORTHERN YUMA COUNTY AND
SOUTHERN RIVERSIDE COUNTY. A FEW ADDITIONAL SHOWERS AND THUNDERSTORMS
ARE CURRENTLY SEEN OVER THE WHITE MOUNTAINS AND NORTH OF THE MOGOLLON
RIM OUTSIDE OF OUR CWA. A BOUNDARY LAYER AND DRYING NORTHERLY FLOW
ALOFT ARE LIMITING DEVELOPMENT CURRENTLY AND LIKELY THROUGH THE REST
OF TODAY. BEST CHANCES FOR THE REST OF TODAY WILL BE OVER HIGHER
TERRAIN AREAS OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA WHERE
PWATS ARE HIGHEST...WHILE LIMITED ACTIVITY ACROSS SOUTHEAST AND
SOUTH-CENTRAL ARIZONA SHOULD MOSTLY STAY OUTSIDE THE PHOENIX AREA.

A SLOW TRANSITION TO A DRIER REGIME IS EXPECTED THROUGH EARLY NEXT
WEEK...BUT STORM CHANCES WILL BE POSSIBLE BOTH SATURDAY AND SUNDAY AS
PWATS ARE FORECAST TO BE AROUND 1.25 INCHES. VERY WEAK FLOW ALOFT ON
SATURDAY POINT TOWARD A TYPICAL MONSOON DAY OVER SOUTH-CENTRAL AND
SOUTHEAST ARIZONA WITH HIGH TERRAIN STORMS FOLLOWED BY THE POTENTIAL
FOR A FEW STORMS OVER THE LOWER DESERTS FROM OUTFLOW INTERACTIONS.
FOR SUNDAY...PWATS START TO DROP BELOW ONE INCH OVER THE LOWER
COLORADO RIVER VALLEY...WHILE STILL REMAINING BETWEEN 1.25-1.40
INCHES OVER SOUTH-CENTRAL ARIZONA. MORE FAVORABLE DIFLUENT FLOW ALOFT
IS LIKELY ON SUNDAY OVER SOUTH-CENTRAL ARIZONA WHICH SHOULD LEAD TO
SLIGHTLY BETTER STORM CHANCES OVER THE LOWER DESERTS. TEMPERATURES
THROUGH THE WEEKEND WILL REMAIN QUITE WARM FOR THIS TIME OF YEAR AS
HIGHS LIKELY WILL BREACH 110 DEGREES IN OUR WESTERN ZONES AND IN A
104-109 RANGE OVER THE SOUTH-CENTRAL ARIZONA DESERTS.

THE DRYING TREND WILL GAIN STEAM STARTING MONDAY AND CONTINUE THROUGH
AT LEAST THE MIDDLE OF NEXT WEEK. UPPER TROFFING IS FORECAST TO SET
UP BOTH ALONG THE WEST COAST AND INLAND OVER THE PAC NORTHWEST AND
THIS WILL LEAD TO STRENGTHENING SOUTHWEST FLOW ALOFT TO WORK INTO THE
DESERT SOUTHWEST AND GRADUALLY THIN OUT THE MOISTURE OVER SE
CALIFORNIA AND THE LOWER AZ DESERTS. BY NEXT MONDAY THUNDERSTORM
CHANCES SHOULD BE CONFINED PRIMARILY TO HIGHER TERRAIN AREAS EAST OF
PHOENIX...ZONE 24 TO BE EXACT. THERE WILL BE PERIODS OF HIGH CLOUDS
MOVING THROUGH THE FLOW BUT OVERALL DESERTS SHOULD RANGE FROM MOSTLY
SUNNY TO PARTLY SUNNY EACH DAY FROM MONDAY ONWARD. AS THE UPPER
TROFFING DEVELOPS AND HEIGHTS FALL...HIGH TEMPERATURES WILL STEADILY
FALL OFF AND BY NEXT MONDAY THE WARMER LOWER DESERTS WILL BE WELL
UNDER 110. THE GREATER PHOENIX AREA IS FORECAST TO DROP TO 105 ON
MONDAY...AND EVENTUALLY TO 103 ON WEDNESDAY AND THURSDAY. THE 103
DEGREE READINGS WILL EQUAL THE CLIMATE NORMALS FOR THOSE DAYS.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND..
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

EXCEPT FOR VERY ISOLATED THUNDERSTORMS OVER THE MOUNTAINS OF EASTERN
ARIZONA...EXPECT QUIET CONDITIONS THE REST OF THE NIGHT AND THROUGH
THE MORNING. RENEWED STORM DEVELOPMENT OVER HIGHER TERRAIN AND
SOUTHEAST ARIZONA SATURDAY AFTERNOON WITH ONLY A SLIGHT CHANCE OF
STORMS AT ANY GIVEN TAF SITE. OTHERWISE ONLY SOME HIGH CLOUDS ALONG
WITH FAMILIAR DIURNAL WIND PATTERNS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
DRIER AND WARMER WEATHER WILL GRADUALLY SPREAD INTO REGION FROM THE
WEST. A SLIGHT CHANCE OF AFTERNOON AND EVENING TSTMS WILL STILL BE
FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY. HIGH
TEMPERATURES THROUGH THE WEEK WILL BE NEAR NORMAL WITH HOTTER DESERT
LOCATIONS NEARING 110 ON MONDAY. MINIMUM HUMIDITIES WILL FALL INTO
THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY
ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES
REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST
WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS
EXPECTED.

&&

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...AJ
PREVIOUS DISCUSSION...KUHLMAN/CB
AVIATION...AJ
FIRE WEATHER...DEWEY





000
FXUS65 KPSR 290455
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
955 PM MST FRI AUG 28 2015

.SYNOPSIS...
STRONG HIGH PRESSURE ALOFT WILL KEEP HIGH TEMPERATURES WELL ABOVE
SEASONAL NORMALS THROUGH SATURDAY WITH HOTTER LOWER DESERTS REACHING
OR EXCEEDING 110. THERE WILL BE SUFFICIENT MOISTURE EAST OF THE LOWER
COLORADO RIVER TO SUPPORT ISOLATED TO SCATTERED AFTERNOON AND EVENING
THUNDERSTORMS THROUGH SUNDAY. STARTING MONDAY DRIER WESTERLY FLOW
ALOFT WILL PUSH THE MOISTURE OFF TO THE EAST LIMITING STORM CHANCES
PRIMARILY TO HIGHER TERRAIN AREAS TO THE EAST OF PHOENIX. THERE WILL
BE A GRADUAL COOLING TREND STARTING SUNDAY WITH CENTRAL DESERTS HIGH
TEMPERATURES DROPPING TO AROUND SEASONAL NORMALS BY THE MIDDLE OF
NEXT WEEK.

&&

.DISCUSSION...
STORM ACTIVITY HAS DISSIPATED THIS EVENING ACROSS ARIZONA AND
SOUTHEAST CALIFORNIA. ANTICIPATE THAT TO REMAIN THE CASE OVERNIGHT AS
LOWER LEVELS HAVE HAD SOME DRYING OVER A GOOD PORTION OF
ARIZONA PER 00Z SOUNDINGS...LESS SO OVER SOUTHWEST ARIZONA AND INTO
FAR SOUTHEAST CALIFORNIA. ALSO...SONORA IS FAIRLY QUIET AND NEAREST
LARGE ACTIVITY IS OVER EASTERN NEW MEXICO. THERE COULD BE A STRAY
ISOLATED STORM THANKS TO A LONG TRAVELED GRAVITY WAVE BUT
PROBABILITY TOO LOW TO HOLD ON TO POPS FOR THE OVERNIGHT PERIOD. OF
NOTE...THE LATEST HRRR DOES DEVELOP SOME ACTIVITY OVER SOUTHEAST
ARIZONA WITH SOME VERY ISOLATED STORMS MAKING THEIR WAY INTO SOUTH-
CENTRAL ARIZONA LATE TONIGHT. LOCAL HI-RES MODELS AND 00Z NCAR
ENSEMBLE ARE NOT REFLECTING THAT. LATEST NAM AND GFS INDICATE SOME
RECOVERY OF MOISTURE SATURDAY AND THUS MORE STORMS THAN
TODAY...MAINLY OVER SOUTHEAST ARIZONA. ALSO SOME SOUTHERLY MID LEVEL
WINDS WHICH SHOULD BRING STORMS CLOSER TO THE PHOENIX AREA THAN
TODAY. NO CHANGES TO CURRENT FORECASTS.

&&

.PREVIOUS DISCUSSION ISSUED 152 PM...
AS EXPECTED THERE HAS BEEN A LATER ONSET TO STORM ACTIVITY TODAY
WITH ONLY A FEW SHOWERS AND THUNDERSTORMS IN NORTHERN YUMA COUNTY AND
SOUTHERN RIVERSIDE COUNTY. A FEW ADDITIONAL SHOWERS AND THUNDERSTORMS
ARE CURRENTLY SEEN OVER THE WHITE MOUNTAINS AND NORTH OF THE MOGOLLON
RIM OUTSIDE OF OUR CWA. A BOUNDARY LAYER AND DRYING NORTHERLY FLOW
ALOFT ARE LIMITING DEVELOPMENT CURRENTLY AND LIKELY THROUGH THE REST
OF TODAY. BEST CHANCES FOR THE REST OF TODAY WILL BE OVER HIGHER
TERRAIN AREAS OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA WHERE
PWATS ARE HIGHEST...WHILE LIMITED ACTIVITY ACROSS SOUTHEAST AND
SOUTH-CENTRAL ARIZONA SHOULD MOSTLY STAY OUTSIDE THE PHOENIX AREA.

A SLOW TRANSITION TO A DRIER REGIME IS EXPECTED THROUGH EARLY NEXT
WEEK...BUT STORM CHANCES WILL BE POSSIBLE BOTH SATURDAY AND SUNDAY AS
PWATS ARE FORECAST TO BE AROUND 1.25 INCHES. VERY WEAK FLOW ALOFT ON
SATURDAY POINT TOWARD A TYPICAL MONSOON DAY OVER SOUTH-CENTRAL AND
SOUTHEAST ARIZONA WITH HIGH TERRAIN STORMS FOLLOWED BY THE POTENTIAL
FOR A FEW STORMS OVER THE LOWER DESERTS FROM OUTFLOW INTERACTIONS.
FOR SUNDAY...PWATS START TO DROP BELOW ONE INCH OVER THE LOWER
COLORADO RIVER VALLEY...WHILE STILL REMAINING BETWEEN 1.25-1.40
INCHES OVER SOUTH-CENTRAL ARIZONA. MORE FAVORABLE DIFLUENT FLOW ALOFT
IS LIKELY ON SUNDAY OVER SOUTH-CENTRAL ARIZONA WHICH SHOULD LEAD TO
SLIGHTLY BETTER STORM CHANCES OVER THE LOWER DESERTS. TEMPERATURES
THROUGH THE WEEKEND WILL REMAIN QUITE WARM FOR THIS TIME OF YEAR AS
HIGHS LIKELY WILL BREACH 110 DEGREES IN OUR WESTERN ZONES AND IN A
104-109 RANGE OVER THE SOUTH-CENTRAL ARIZONA DESERTS.

THE DRYING TREND WILL GAIN STEAM STARTING MONDAY AND CONTINUE THROUGH
AT LEAST THE MIDDLE OF NEXT WEEK. UPPER TROFFING IS FORECAST TO SET
UP BOTH ALONG THE WEST COAST AND INLAND OVER THE PAC NORTHWEST AND
THIS WILL LEAD TO STRENGTHENING SOUTHWEST FLOW ALOFT TO WORK INTO THE
DESERT SOUTHWEST AND GRADUALLY THIN OUT THE MOISTURE OVER SE
CALIFORNIA AND THE LOWER AZ DESERTS. BY NEXT MONDAY THUNDERSTORM
CHANCES SHOULD BE CONFINED PRIMARILY TO HIGHER TERRAIN AREAS EAST OF
PHOENIX...ZONE 24 TO BE EXACT. THERE WILL BE PERIODS OF HIGH CLOUDS
MOVING THROUGH THE FLOW BUT OVERALL DESERTS SHOULD RANGE FROM MOSTLY
SUNNY TO PARTLY SUNNY EACH DAY FROM MONDAY ONWARD. AS THE UPPER
TROFFING DEVELOPS AND HEIGHTS FALL...HIGH TEMPERATURES WILL STEADILY
FALL OFF AND BY NEXT MONDAY THE WARMER LOWER DESERTS WILL BE WELL
UNDER 110. THE GREATER PHOENIX AREA IS FORECAST TO DROP TO 105 ON
MONDAY...AND EVENTUALLY TO 103 ON WEDNESDAY AND THURSDAY. THE 103
DEGREE READINGS WILL EQUAL THE CLIMATE NORMALS FOR THOSE DAYS.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND..
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

EXCEPT FOR VERY ISOLATED THUNDERSTORMS OVER THE MOUNTAINS OF EASTERN
ARIZONA...EXPECT QUIET CONDITIONS THE REST OF THE NIGHT AND THROUGH
THE MORNING. RENEWED STORM DEVELOPMENT OVER HIGHER TERRAIN AND
SOUTHEAST ARIZONA SATURDAY AFTERNOON WITH ONLY A SLIGHT CHANCE OF
STORMS AT ANY GIVEN TAF SITE. OTHERWISE ONLY SOME HIGH CLOUDS ALONG
WITH FAMILIAR DIURNAL WIND PATTERNS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
DRIER AND WARMER WEATHER WILL GRADUALLY SPREAD INTO REGION FROM THE
WEST. A SLIGHT CHANCE OF AFTERNOON AND EVENING TSTMS WILL STILL BE
FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY. HIGH
TEMPERATURES THROUGH THE WEEK WILL BE NEAR NORMAL WITH HOTTER DESERT
LOCATIONS NEARING 110 ON MONDAY. MINIMUM HUMIDITIES WILL FALL INTO
THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY
ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES
REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST
WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS
EXPECTED.

&&

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...AJ
PREVIOUS DISCUSSION...KUHLMAN/CB
AVIATION...AJ
FIRE WEATHER...DEWEY




000
FXUS65 KPSR 290455
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
955 PM MST FRI AUG 28 2015

.SYNOPSIS...
STRONG HIGH PRESSURE ALOFT WILL KEEP HIGH TEMPERATURES WELL ABOVE
SEASONAL NORMALS THROUGH SATURDAY WITH HOTTER LOWER DESERTS REACHING
OR EXCEEDING 110. THERE WILL BE SUFFICIENT MOISTURE EAST OF THE LOWER
COLORADO RIVER TO SUPPORT ISOLATED TO SCATTERED AFTERNOON AND EVENING
THUNDERSTORMS THROUGH SUNDAY. STARTING MONDAY DRIER WESTERLY FLOW
ALOFT WILL PUSH THE MOISTURE OFF TO THE EAST LIMITING STORM CHANCES
PRIMARILY TO HIGHER TERRAIN AREAS TO THE EAST OF PHOENIX. THERE WILL
BE A GRADUAL COOLING TREND STARTING SUNDAY WITH CENTRAL DESERTS HIGH
TEMPERATURES DROPPING TO AROUND SEASONAL NORMALS BY THE MIDDLE OF
NEXT WEEK.

&&

.DISCUSSION...
STORM ACTIVITY HAS DISSIPATED THIS EVENING ACROSS ARIZONA AND
SOUTHEAST CALIFORNIA. ANTICIPATE THAT TO REMAIN THE CASE OVERNIGHT AS
LOWER LEVELS HAVE HAD SOME DRYING OVER A GOOD PORTION OF
ARIZONA PER 00Z SOUNDINGS...LESS SO OVER SOUTHWEST ARIZONA AND INTO
FAR SOUTHEAST CALIFORNIA. ALSO...SONORA IS FAIRLY QUIET AND NEAREST
LARGE ACTIVITY IS OVER EASTERN NEW MEXICO. THERE COULD BE A STRAY
ISOLATED STORM THANKS TO A LONG TRAVELED GRAVITY WAVE BUT
PROBABILITY TOO LOW TO HOLD ON TO POPS FOR THE OVERNIGHT PERIOD. OF
NOTE...THE LATEST HRRR DOES DEVELOP SOME ACTIVITY OVER SOUTHEAST
ARIZONA WITH SOME VERY ISOLATED STORMS MAKING THEIR WAY INTO SOUTH-
CENTRAL ARIZONA LATE TONIGHT. LOCAL HI-RES MODELS AND 00Z NCAR
ENSEMBLE ARE NOT REFLECTING THAT. LATEST NAM AND GFS INDICATE SOME
RECOVERY OF MOISTURE SATURDAY AND THUS MORE STORMS THAN
TODAY...MAINLY OVER SOUTHEAST ARIZONA. ALSO SOME SOUTHERLY MID LEVEL
WINDS WHICH SHOULD BRING STORMS CLOSER TO THE PHOENIX AREA THAN
TODAY. NO CHANGES TO CURRENT FORECASTS.

&&

.PREVIOUS DISCUSSION ISSUED 152 PM...
AS EXPECTED THERE HAS BEEN A LATER ONSET TO STORM ACTIVITY TODAY
WITH ONLY A FEW SHOWERS AND THUNDERSTORMS IN NORTHERN YUMA COUNTY AND
SOUTHERN RIVERSIDE COUNTY. A FEW ADDITIONAL SHOWERS AND THUNDERSTORMS
ARE CURRENTLY SEEN OVER THE WHITE MOUNTAINS AND NORTH OF THE MOGOLLON
RIM OUTSIDE OF OUR CWA. A BOUNDARY LAYER AND DRYING NORTHERLY FLOW
ALOFT ARE LIMITING DEVELOPMENT CURRENTLY AND LIKELY THROUGH THE REST
OF TODAY. BEST CHANCES FOR THE REST OF TODAY WILL BE OVER HIGHER
TERRAIN AREAS OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA WHERE
PWATS ARE HIGHEST...WHILE LIMITED ACTIVITY ACROSS SOUTHEAST AND
SOUTH-CENTRAL ARIZONA SHOULD MOSTLY STAY OUTSIDE THE PHOENIX AREA.

A SLOW TRANSITION TO A DRIER REGIME IS EXPECTED THROUGH EARLY NEXT
WEEK...BUT STORM CHANCES WILL BE POSSIBLE BOTH SATURDAY AND SUNDAY AS
PWATS ARE FORECAST TO BE AROUND 1.25 INCHES. VERY WEAK FLOW ALOFT ON
SATURDAY POINT TOWARD A TYPICAL MONSOON DAY OVER SOUTH-CENTRAL AND
SOUTHEAST ARIZONA WITH HIGH TERRAIN STORMS FOLLOWED BY THE POTENTIAL
FOR A FEW STORMS OVER THE LOWER DESERTS FROM OUTFLOW INTERACTIONS.
FOR SUNDAY...PWATS START TO DROP BELOW ONE INCH OVER THE LOWER
COLORADO RIVER VALLEY...WHILE STILL REMAINING BETWEEN 1.25-1.40
INCHES OVER SOUTH-CENTRAL ARIZONA. MORE FAVORABLE DIFLUENT FLOW ALOFT
IS LIKELY ON SUNDAY OVER SOUTH-CENTRAL ARIZONA WHICH SHOULD LEAD TO
SLIGHTLY BETTER STORM CHANCES OVER THE LOWER DESERTS. TEMPERATURES
THROUGH THE WEEKEND WILL REMAIN QUITE WARM FOR THIS TIME OF YEAR AS
HIGHS LIKELY WILL BREACH 110 DEGREES IN OUR WESTERN ZONES AND IN A
104-109 RANGE OVER THE SOUTH-CENTRAL ARIZONA DESERTS.

THE DRYING TREND WILL GAIN STEAM STARTING MONDAY AND CONTINUE THROUGH
AT LEAST THE MIDDLE OF NEXT WEEK. UPPER TROFFING IS FORECAST TO SET
UP BOTH ALONG THE WEST COAST AND INLAND OVER THE PAC NORTHWEST AND
THIS WILL LEAD TO STRENGTHENING SOUTHWEST FLOW ALOFT TO WORK INTO THE
DESERT SOUTHWEST AND GRADUALLY THIN OUT THE MOISTURE OVER SE
CALIFORNIA AND THE LOWER AZ DESERTS. BY NEXT MONDAY THUNDERSTORM
CHANCES SHOULD BE CONFINED PRIMARILY TO HIGHER TERRAIN AREAS EAST OF
PHOENIX...ZONE 24 TO BE EXACT. THERE WILL BE PERIODS OF HIGH CLOUDS
MOVING THROUGH THE FLOW BUT OVERALL DESERTS SHOULD RANGE FROM MOSTLY
SUNNY TO PARTLY SUNNY EACH DAY FROM MONDAY ONWARD. AS THE UPPER
TROFFING DEVELOPS AND HEIGHTS FALL...HIGH TEMPERATURES WILL STEADILY
FALL OFF AND BY NEXT MONDAY THE WARMER LOWER DESERTS WILL BE WELL
UNDER 110. THE GREATER PHOENIX AREA IS FORECAST TO DROP TO 105 ON
MONDAY...AND EVENTUALLY TO 103 ON WEDNESDAY AND THURSDAY. THE 103
DEGREE READINGS WILL EQUAL THE CLIMATE NORMALS FOR THOSE DAYS.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND..
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

EXCEPT FOR VERY ISOLATED THUNDERSTORMS OVER THE MOUNTAINS OF EASTERN
ARIZONA...EXPECT QUIET CONDITIONS THE REST OF THE NIGHT AND THROUGH
THE MORNING. RENEWED STORM DEVELOPMENT OVER HIGHER TERRAIN AND
SOUTHEAST ARIZONA SATURDAY AFTERNOON WITH ONLY A SLIGHT CHANCE OF
STORMS AT ANY GIVEN TAF SITE. OTHERWISE ONLY SOME HIGH CLOUDS ALONG
WITH FAMILIAR DIURNAL WIND PATTERNS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
DRIER AND WARMER WEATHER WILL GRADUALLY SPREAD INTO REGION FROM THE
WEST. A SLIGHT CHANCE OF AFTERNOON AND EVENING TSTMS WILL STILL BE
FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY. HIGH
TEMPERATURES THROUGH THE WEEK WILL BE NEAR NORMAL WITH HOTTER DESERT
LOCATIONS NEARING 110 ON MONDAY. MINIMUM HUMIDITIES WILL FALL INTO
THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY
ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES
REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST
WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS
EXPECTED.

&&

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...AJ
PREVIOUS DISCUSSION...KUHLMAN/CB
AVIATION...AJ
FIRE WEATHER...DEWEY





000
FXUS65 KPSR 282052
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
152 PM MST FRI AUG 28 2015

.SYNOPSIS...
STRONG HIGH PRESSURE ALOFT WILL KEEP HIGH TEMPERATURES WELL ABOVE
SEASONAL NORMALS THROUGH SATURDAY WITH HOTTER LOWER DESERTS REACHING
OR EXCEEDING 110. THERE WILL BE SUFFICIENT MOISTURE EAST OF THE LOWER
COLORADO RIVER TO SUPPORT ISOLATED TO SCATTERED AFTERNOON AND EVENING
THUNDERSTORMS THROUGH SUNDAY. STARTING MONDAY DRIER WESTERLY FLOW
ALOFT WILL PUSH THE MOISTURE OFF TO THE EAST LIMITING STORM CHANCES
PRIMARILY TO HIGHER TERRAIN AREAS TO THE EAST OF PHOENIX. THERE WILL
BE A GRADUAL COOLING TREND STARTING SUNDAY WITH CENTRAL DESERTS HIGH
TEMPERATURES DROPPING TO AROUND SEASONAL NORMALS BY THE MIDDLE OF
NEXT WEEK.

&&

.DISCUSSION...
AS EXPECTED THERE HAS BEEN A LATER ONSET TO STORM ACTIVITY TODAY WITH
ONLY A FEW SHOWERS AND THUNDERSTORMS IN NORTHERN YUMA COUNTY AND
SOUTHERN RIVERSIDE COUNTY. A FEW ADDITIONAL SHOWERS AND THUNDERSTORMS
ARE CURRENTLY SEEN OVER THE WHITE MOUNTAINS AND NORTH OF THE MOGOLLON
RIM OUTSIDE OF OUR CWA. A BOUNDARY LAYER AND DRYING NORTHERLY FLOW
ALOFT ARE LIMITING DEVELOPMENT CURRENTLY AND LIKELY THROUGH THE REST
OF TODAY. BEST CHANCES FOR THE REST OF TODAY WILL BE OVER HIGHER
TERRAIN AREAS OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA WHERE
PWATS ARE HIGHEST...WHILE LIMITED ACTIVITY ACROSS SOUTHEAST AND
SOUTH-CENTRAL ARIZONA SHOULD MOSTLY STAY OUTSIDE THE PHOENIX AREA.

A SLOW TRANSITION TO A DRIER REGIME IS EXPECTED THROUGH EARLY NEXT
WEEK...BUT STORM CHANCES WILL BE POSSIBLE BOTH SATURDAY AND SUNDAY AS
PWATS ARE FORECAST TO BE AROUND 1.25 INCHES. VERY WEAK FLOW ALOFT ON
SATURDAY POINT TOWARD A TYPICAL MONSOON DAY OVER SOUTH-CENTRAL AND
SOUTHEAST ARIZONA WITH HIGH TERRAIN STORMS FOLLOWED BY THE POTENTIAL
FOR A FEW STORMS OVER THE LOWER DESERTS FROM OUTFLOW INTERACTIONS.
FOR SUNDAY...PWATS START TO DROP BELOW ONE INCH OVER THE LOWER
COLORADO RIVER VALLEY...WHILE STILL REMAINING BETWEEN 1.25-1.40
INCHES OVER SOUTH-CENTRAL ARIZONA. MORE FAVORABLE DIFLUENT FLOW ALOFT
IS LIKELY ON SUNDAY OVER SOUTH-CENTRAL ARIZONA WHICH SHOULD LEAD TO
SLIGHTLY BETTER STORM CHANCES OVER THE LOWER DESERTS. TEMPERATURES
THROUGH THE WEEKEND WILL REMAIN QUITE WARM FOR THIS TIME OF YEAR AS
HIGHS LIKELY WILL BREACH 110 DEGREES IN OUR WESTERN ZONES AND IN A
104-109 RANGE OVER THE SOUTH-CENTRAL ARIZONA DESERTS.

THE DRYING TREND WILL GAIN STEAM STARTING MONDAY AND CONTINUE THROUGH
AT LEAST THE MIDDLE OF NEXT WEEK. UPPER TROFFING IS FORECAST TO SET
UP BOTH ALONG THE WEST COAST AND INLAND OVER THE PAC NORTHWEST AND
THIS WILL LEAD TO STRENGTHENING SOUTHWEST FLOW ALOFT TO WORK INTO THE
DESERT SOUTHWEST AND GRADUALLY THIN OUT THE MOISTURE OVER SE
CALIFORNIA AND THE LOWER AZ DESERTS. BY NEXT MONDAY THUNDERSTORM
CHANCES SHOULD BE CONFINED PRIMARILY TO HIGHER TERRAIN AREAS EAST OF
PHOENIX...ZONE 24 TO BE EXACT. THERE WILL BE PERIODS OF HIGH CLOUDS
MOVING THROUGH THE FLOW BUT OVERALL DESERTS SHOULD RANGE FROM MOSTLY
SUNNY TO PARTLY SUNNY EACH DAY FROM MONDAY ONWARD. AS THE UPPER
TROFFING DEVELOPS AND HEIGHTS FALL...HIGH TEMPERATURES WILL STEADILY
FALL OFF AND BY NEXT MONDAY THE WARMER LOWER DESERTS WILL BE WELL
UNDER 110. THE GREATER PHOENIX AREA IS FORECAST TO DROP TO 105 ON
MONDAY...AND EVENTUALLY TO 103 ON WEDNESDAY AND THURSDAY. THE 103
DEGREE READINGS WILL EQUAL THE CLIMATE NORMALS FOR THOSE DAYS.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND..
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

SKIES WILL CONTINUE TO BE MOSTLY CLEAR WITH SOME SCT CUMULUS
DEVELOPMENT NORTH AND EAST ALONG THE RIM OF ARIZONA. EXPECTING
AFTERNOON THUNDERSTORMS TO REMAIN MOSTLY NORTH AND EAST OF PHOENIX
TERMINALS...HOWEVER COULD BE IN THE VICINITY OF KSDL. CONFIDENCE IS
LOW TO INCLUDE ANY MENTION IN ANY OF THE TAFS. OUTFLOW WINDS MAY
IMPACT PHOENIX AREA TERMINALS...BUT AGAIN CONFIDENCE IS LOW AS ALL
GUIDANCE DOES NOT LOOK FAVORABLE. SOUTHEAST CALIFORNIA WILL REMAIN
CLEAR SKIES AND MOSTLY LIGHT WINDS AT OR BELOW 10KTS THROUGH THE
PERIOD.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
DRIER AND WARMER WEATHER WILL GRADUALLY SPREAD INTO REGION FROM THE
WEST. A SLIGHT CHANCE OF AFTERNOON AND EVENING TSTMS WILL STILL BE
FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY. HIGH
TEMPERATURES THROUGH THE WEEK WILL BE NEAR NORMAL WITH HOTTER DESERT
LOCATIONS NEARING 110 ON MONDAY. MINIMUM HUMIDITIES WILL FALL INTO
THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY
ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES
REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST
WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS
EXPECTED.

&&

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...KUHLMAN/CB
AVIATION...DEWEY
FIRE WEATHER...DEWEY




000
FXUS65 KPSR 282052
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
152 PM MST FRI AUG 28 2015

.SYNOPSIS...
STRONG HIGH PRESSURE ALOFT WILL KEEP HIGH TEMPERATURES WELL ABOVE
SEASONAL NORMALS THROUGH SATURDAY WITH HOTTER LOWER DESERTS REACHING
OR EXCEEDING 110. THERE WILL BE SUFFICIENT MOISTURE EAST OF THE LOWER
COLORADO RIVER TO SUPPORT ISOLATED TO SCATTERED AFTERNOON AND EVENING
THUNDERSTORMS THROUGH SUNDAY. STARTING MONDAY DRIER WESTERLY FLOW
ALOFT WILL PUSH THE MOISTURE OFF TO THE EAST LIMITING STORM CHANCES
PRIMARILY TO HIGHER TERRAIN AREAS TO THE EAST OF PHOENIX. THERE WILL
BE A GRADUAL COOLING TREND STARTING SUNDAY WITH CENTRAL DESERTS HIGH
TEMPERATURES DROPPING TO AROUND SEASONAL NORMALS BY THE MIDDLE OF
NEXT WEEK.

&&

.DISCUSSION...
AS EXPECTED THERE HAS BEEN A LATER ONSET TO STORM ACTIVITY TODAY WITH
ONLY A FEW SHOWERS AND THUNDERSTORMS IN NORTHERN YUMA COUNTY AND
SOUTHERN RIVERSIDE COUNTY. A FEW ADDITIONAL SHOWERS AND THUNDERSTORMS
ARE CURRENTLY SEEN OVER THE WHITE MOUNTAINS AND NORTH OF THE MOGOLLON
RIM OUTSIDE OF OUR CWA. A BOUNDARY LAYER AND DRYING NORTHERLY FLOW
ALOFT ARE LIMITING DEVELOPMENT CURRENTLY AND LIKELY THROUGH THE REST
OF TODAY. BEST CHANCES FOR THE REST OF TODAY WILL BE OVER HIGHER
TERRAIN AREAS OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA WHERE
PWATS ARE HIGHEST...WHILE LIMITED ACTIVITY ACROSS SOUTHEAST AND
SOUTH-CENTRAL ARIZONA SHOULD MOSTLY STAY OUTSIDE THE PHOENIX AREA.

A SLOW TRANSITION TO A DRIER REGIME IS EXPECTED THROUGH EARLY NEXT
WEEK...BUT STORM CHANCES WILL BE POSSIBLE BOTH SATURDAY AND SUNDAY AS
PWATS ARE FORECAST TO BE AROUND 1.25 INCHES. VERY WEAK FLOW ALOFT ON
SATURDAY POINT TOWARD A TYPICAL MONSOON DAY OVER SOUTH-CENTRAL AND
SOUTHEAST ARIZONA WITH HIGH TERRAIN STORMS FOLLOWED BY THE POTENTIAL
FOR A FEW STORMS OVER THE LOWER DESERTS FROM OUTFLOW INTERACTIONS.
FOR SUNDAY...PWATS START TO DROP BELOW ONE INCH OVER THE LOWER
COLORADO RIVER VALLEY...WHILE STILL REMAINING BETWEEN 1.25-1.40
INCHES OVER SOUTH-CENTRAL ARIZONA. MORE FAVORABLE DIFLUENT FLOW ALOFT
IS LIKELY ON SUNDAY OVER SOUTH-CENTRAL ARIZONA WHICH SHOULD LEAD TO
SLIGHTLY BETTER STORM CHANCES OVER THE LOWER DESERTS. TEMPERATURES
THROUGH THE WEEKEND WILL REMAIN QUITE WARM FOR THIS TIME OF YEAR AS
HIGHS LIKELY WILL BREACH 110 DEGREES IN OUR WESTERN ZONES AND IN A
104-109 RANGE OVER THE SOUTH-CENTRAL ARIZONA DESERTS.

THE DRYING TREND WILL GAIN STEAM STARTING MONDAY AND CONTINUE THROUGH
AT LEAST THE MIDDLE OF NEXT WEEK. UPPER TROFFING IS FORECAST TO SET
UP BOTH ALONG THE WEST COAST AND INLAND OVER THE PAC NORTHWEST AND
THIS WILL LEAD TO STRENGTHENING SOUTHWEST FLOW ALOFT TO WORK INTO THE
DESERT SOUTHWEST AND GRADUALLY THIN OUT THE MOISTURE OVER SE
CALIFORNIA AND THE LOWER AZ DESERTS. BY NEXT MONDAY THUNDERSTORM
CHANCES SHOULD BE CONFINED PRIMARILY TO HIGHER TERRAIN AREAS EAST OF
PHOENIX...ZONE 24 TO BE EXACT. THERE WILL BE PERIODS OF HIGH CLOUDS
MOVING THROUGH THE FLOW BUT OVERALL DESERTS SHOULD RANGE FROM MOSTLY
SUNNY TO PARTLY SUNNY EACH DAY FROM MONDAY ONWARD. AS THE UPPER
TROFFING DEVELOPS AND HEIGHTS FALL...HIGH TEMPERATURES WILL STEADILY
FALL OFF AND BY NEXT MONDAY THE WARMER LOWER DESERTS WILL BE WELL
UNDER 110. THE GREATER PHOENIX AREA IS FORECAST TO DROP TO 105 ON
MONDAY...AND EVENTUALLY TO 103 ON WEDNESDAY AND THURSDAY. THE 103
DEGREE READINGS WILL EQUAL THE CLIMATE NORMALS FOR THOSE DAYS.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND..
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

SKIES WILL CONTINUE TO BE MOSTLY CLEAR WITH SOME SCT CUMULUS
DEVELOPMENT NORTH AND EAST ALONG THE RIM OF ARIZONA. EXPECTING
AFTERNOON THUNDERSTORMS TO REMAIN MOSTLY NORTH AND EAST OF PHOENIX
TERMINALS...HOWEVER COULD BE IN THE VICINITY OF KSDL. CONFIDENCE IS
LOW TO INCLUDE ANY MENTION IN ANY OF THE TAFS. OUTFLOW WINDS MAY
IMPACT PHOENIX AREA TERMINALS...BUT AGAIN CONFIDENCE IS LOW AS ALL
GUIDANCE DOES NOT LOOK FAVORABLE. SOUTHEAST CALIFORNIA WILL REMAIN
CLEAR SKIES AND MOSTLY LIGHT WINDS AT OR BELOW 10KTS THROUGH THE
PERIOD.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
DRIER AND WARMER WEATHER WILL GRADUALLY SPREAD INTO REGION FROM THE
WEST. A SLIGHT CHANCE OF AFTERNOON AND EVENING TSTMS WILL STILL BE
FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY. HIGH
TEMPERATURES THROUGH THE WEEK WILL BE NEAR NORMAL WITH HOTTER DESERT
LOCATIONS NEARING 110 ON MONDAY. MINIMUM HUMIDITIES WILL FALL INTO
THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY
ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES
REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST
WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS
EXPECTED.

&&

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...KUHLMAN/CB
AVIATION...DEWEY
FIRE WEATHER...DEWEY




000
FXUS65 KPSR 282052
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
152 PM MST FRI AUG 28 2015

.SYNOPSIS...
STRONG HIGH PRESSURE ALOFT WILL KEEP HIGH TEMPERATURES WELL ABOVE
SEASONAL NORMALS THROUGH SATURDAY WITH HOTTER LOWER DESERTS REACHING
OR EXCEEDING 110. THERE WILL BE SUFFICIENT MOISTURE EAST OF THE LOWER
COLORADO RIVER TO SUPPORT ISOLATED TO SCATTERED AFTERNOON AND EVENING
THUNDERSTORMS THROUGH SUNDAY. STARTING MONDAY DRIER WESTERLY FLOW
ALOFT WILL PUSH THE MOISTURE OFF TO THE EAST LIMITING STORM CHANCES
PRIMARILY TO HIGHER TERRAIN AREAS TO THE EAST OF PHOENIX. THERE WILL
BE A GRADUAL COOLING TREND STARTING SUNDAY WITH CENTRAL DESERTS HIGH
TEMPERATURES DROPPING TO AROUND SEASONAL NORMALS BY THE MIDDLE OF
NEXT WEEK.

&&

.DISCUSSION...
AS EXPECTED THERE HAS BEEN A LATER ONSET TO STORM ACTIVITY TODAY WITH
ONLY A FEW SHOWERS AND THUNDERSTORMS IN NORTHERN YUMA COUNTY AND
SOUTHERN RIVERSIDE COUNTY. A FEW ADDITIONAL SHOWERS AND THUNDERSTORMS
ARE CURRENTLY SEEN OVER THE WHITE MOUNTAINS AND NORTH OF THE MOGOLLON
RIM OUTSIDE OF OUR CWA. A BOUNDARY LAYER AND DRYING NORTHERLY FLOW
ALOFT ARE LIMITING DEVELOPMENT CURRENTLY AND LIKELY THROUGH THE REST
OF TODAY. BEST CHANCES FOR THE REST OF TODAY WILL BE OVER HIGHER
TERRAIN AREAS OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA WHERE
PWATS ARE HIGHEST...WHILE LIMITED ACTIVITY ACROSS SOUTHEAST AND
SOUTH-CENTRAL ARIZONA SHOULD MOSTLY STAY OUTSIDE THE PHOENIX AREA.

A SLOW TRANSITION TO A DRIER REGIME IS EXPECTED THROUGH EARLY NEXT
WEEK...BUT STORM CHANCES WILL BE POSSIBLE BOTH SATURDAY AND SUNDAY AS
PWATS ARE FORECAST TO BE AROUND 1.25 INCHES. VERY WEAK FLOW ALOFT ON
SATURDAY POINT TOWARD A TYPICAL MONSOON DAY OVER SOUTH-CENTRAL AND
SOUTHEAST ARIZONA WITH HIGH TERRAIN STORMS FOLLOWED BY THE POTENTIAL
FOR A FEW STORMS OVER THE LOWER DESERTS FROM OUTFLOW INTERACTIONS.
FOR SUNDAY...PWATS START TO DROP BELOW ONE INCH OVER THE LOWER
COLORADO RIVER VALLEY...WHILE STILL REMAINING BETWEEN 1.25-1.40
INCHES OVER SOUTH-CENTRAL ARIZONA. MORE FAVORABLE DIFLUENT FLOW ALOFT
IS LIKELY ON SUNDAY OVER SOUTH-CENTRAL ARIZONA WHICH SHOULD LEAD TO
SLIGHTLY BETTER STORM CHANCES OVER THE LOWER DESERTS. TEMPERATURES
THROUGH THE WEEKEND WILL REMAIN QUITE WARM FOR THIS TIME OF YEAR AS
HIGHS LIKELY WILL BREACH 110 DEGREES IN OUR WESTERN ZONES AND IN A
104-109 RANGE OVER THE SOUTH-CENTRAL ARIZONA DESERTS.

THE DRYING TREND WILL GAIN STEAM STARTING MONDAY AND CONTINUE THROUGH
AT LEAST THE MIDDLE OF NEXT WEEK. UPPER TROFFING IS FORECAST TO SET
UP BOTH ALONG THE WEST COAST AND INLAND OVER THE PAC NORTHWEST AND
THIS WILL LEAD TO STRENGTHENING SOUTHWEST FLOW ALOFT TO WORK INTO THE
DESERT SOUTHWEST AND GRADUALLY THIN OUT THE MOISTURE OVER SE
CALIFORNIA AND THE LOWER AZ DESERTS. BY NEXT MONDAY THUNDERSTORM
CHANCES SHOULD BE CONFINED PRIMARILY TO HIGHER TERRAIN AREAS EAST OF
PHOENIX...ZONE 24 TO BE EXACT. THERE WILL BE PERIODS OF HIGH CLOUDS
MOVING THROUGH THE FLOW BUT OVERALL DESERTS SHOULD RANGE FROM MOSTLY
SUNNY TO PARTLY SUNNY EACH DAY FROM MONDAY ONWARD. AS THE UPPER
TROFFING DEVELOPS AND HEIGHTS FALL...HIGH TEMPERATURES WILL STEADILY
FALL OFF AND BY NEXT MONDAY THE WARMER LOWER DESERTS WILL BE WELL
UNDER 110. THE GREATER PHOENIX AREA IS FORECAST TO DROP TO 105 ON
MONDAY...AND EVENTUALLY TO 103 ON WEDNESDAY AND THURSDAY. THE 103
DEGREE READINGS WILL EQUAL THE CLIMATE NORMALS FOR THOSE DAYS.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND..
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

SKIES WILL CONTINUE TO BE MOSTLY CLEAR WITH SOME SCT CUMULUS
DEVELOPMENT NORTH AND EAST ALONG THE RIM OF ARIZONA. EXPECTING
AFTERNOON THUNDERSTORMS TO REMAIN MOSTLY NORTH AND EAST OF PHOENIX
TERMINALS...HOWEVER COULD BE IN THE VICINITY OF KSDL. CONFIDENCE IS
LOW TO INCLUDE ANY MENTION IN ANY OF THE TAFS. OUTFLOW WINDS MAY
IMPACT PHOENIX AREA TERMINALS...BUT AGAIN CONFIDENCE IS LOW AS ALL
GUIDANCE DOES NOT LOOK FAVORABLE. SOUTHEAST CALIFORNIA WILL REMAIN
CLEAR SKIES AND MOSTLY LIGHT WINDS AT OR BELOW 10KTS THROUGH THE
PERIOD.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
DRIER AND WARMER WEATHER WILL GRADUALLY SPREAD INTO REGION FROM THE
WEST. A SLIGHT CHANCE OF AFTERNOON AND EVENING TSTMS WILL STILL BE
FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY. HIGH
TEMPERATURES THROUGH THE WEEK WILL BE NEAR NORMAL WITH HOTTER DESERT
LOCATIONS NEARING 110 ON MONDAY. MINIMUM HUMIDITIES WILL FALL INTO
THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY
ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES
REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST
WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS
EXPECTED.

&&

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...KUHLMAN/CB
AVIATION...DEWEY
FIRE WEATHER...DEWEY





000
FXUS65 KPSR 282052
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
152 PM MST FRI AUG 28 2015

.SYNOPSIS...
STRONG HIGH PRESSURE ALOFT WILL KEEP HIGH TEMPERATURES WELL ABOVE
SEASONAL NORMALS THROUGH SATURDAY WITH HOTTER LOWER DESERTS REACHING
OR EXCEEDING 110. THERE WILL BE SUFFICIENT MOISTURE EAST OF THE LOWER
COLORADO RIVER TO SUPPORT ISOLATED TO SCATTERED AFTERNOON AND EVENING
THUNDERSTORMS THROUGH SUNDAY. STARTING MONDAY DRIER WESTERLY FLOW
ALOFT WILL PUSH THE MOISTURE OFF TO THE EAST LIMITING STORM CHANCES
PRIMARILY TO HIGHER TERRAIN AREAS TO THE EAST OF PHOENIX. THERE WILL
BE A GRADUAL COOLING TREND STARTING SUNDAY WITH CENTRAL DESERTS HIGH
TEMPERATURES DROPPING TO AROUND SEASONAL NORMALS BY THE MIDDLE OF
NEXT WEEK.

&&

.DISCUSSION...
AS EXPECTED THERE HAS BEEN A LATER ONSET TO STORM ACTIVITY TODAY WITH
ONLY A FEW SHOWERS AND THUNDERSTORMS IN NORTHERN YUMA COUNTY AND
SOUTHERN RIVERSIDE COUNTY. A FEW ADDITIONAL SHOWERS AND THUNDERSTORMS
ARE CURRENTLY SEEN OVER THE WHITE MOUNTAINS AND NORTH OF THE MOGOLLON
RIM OUTSIDE OF OUR CWA. A BOUNDARY LAYER AND DRYING NORTHERLY FLOW
ALOFT ARE LIMITING DEVELOPMENT CURRENTLY AND LIKELY THROUGH THE REST
OF TODAY. BEST CHANCES FOR THE REST OF TODAY WILL BE OVER HIGHER
TERRAIN AREAS OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA WHERE
PWATS ARE HIGHEST...WHILE LIMITED ACTIVITY ACROSS SOUTHEAST AND
SOUTH-CENTRAL ARIZONA SHOULD MOSTLY STAY OUTSIDE THE PHOENIX AREA.

A SLOW TRANSITION TO A DRIER REGIME IS EXPECTED THROUGH EARLY NEXT
WEEK...BUT STORM CHANCES WILL BE POSSIBLE BOTH SATURDAY AND SUNDAY AS
PWATS ARE FORECAST TO BE AROUND 1.25 INCHES. VERY WEAK FLOW ALOFT ON
SATURDAY POINT TOWARD A TYPICAL MONSOON DAY OVER SOUTH-CENTRAL AND
SOUTHEAST ARIZONA WITH HIGH TERRAIN STORMS FOLLOWED BY THE POTENTIAL
FOR A FEW STORMS OVER THE LOWER DESERTS FROM OUTFLOW INTERACTIONS.
FOR SUNDAY...PWATS START TO DROP BELOW ONE INCH OVER THE LOWER
COLORADO RIVER VALLEY...WHILE STILL REMAINING BETWEEN 1.25-1.40
INCHES OVER SOUTH-CENTRAL ARIZONA. MORE FAVORABLE DIFLUENT FLOW ALOFT
IS LIKELY ON SUNDAY OVER SOUTH-CENTRAL ARIZONA WHICH SHOULD LEAD TO
SLIGHTLY BETTER STORM CHANCES OVER THE LOWER DESERTS. TEMPERATURES
THROUGH THE WEEKEND WILL REMAIN QUITE WARM FOR THIS TIME OF YEAR AS
HIGHS LIKELY WILL BREACH 110 DEGREES IN OUR WESTERN ZONES AND IN A
104-109 RANGE OVER THE SOUTH-CENTRAL ARIZONA DESERTS.

THE DRYING TREND WILL GAIN STEAM STARTING MONDAY AND CONTINUE THROUGH
AT LEAST THE MIDDLE OF NEXT WEEK. UPPER TROFFING IS FORECAST TO SET
UP BOTH ALONG THE WEST COAST AND INLAND OVER THE PAC NORTHWEST AND
THIS WILL LEAD TO STRENGTHENING SOUTHWEST FLOW ALOFT TO WORK INTO THE
DESERT SOUTHWEST AND GRADUALLY THIN OUT THE MOISTURE OVER SE
CALIFORNIA AND THE LOWER AZ DESERTS. BY NEXT MONDAY THUNDERSTORM
CHANCES SHOULD BE CONFINED PRIMARILY TO HIGHER TERRAIN AREAS EAST OF
PHOENIX...ZONE 24 TO BE EXACT. THERE WILL BE PERIODS OF HIGH CLOUDS
MOVING THROUGH THE FLOW BUT OVERALL DESERTS SHOULD RANGE FROM MOSTLY
SUNNY TO PARTLY SUNNY EACH DAY FROM MONDAY ONWARD. AS THE UPPER
TROFFING DEVELOPS AND HEIGHTS FALL...HIGH TEMPERATURES WILL STEADILY
FALL OFF AND BY NEXT MONDAY THE WARMER LOWER DESERTS WILL BE WELL
UNDER 110. THE GREATER PHOENIX AREA IS FORECAST TO DROP TO 105 ON
MONDAY...AND EVENTUALLY TO 103 ON WEDNESDAY AND THURSDAY. THE 103
DEGREE READINGS WILL EQUAL THE CLIMATE NORMALS FOR THOSE DAYS.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND..
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

SKIES WILL CONTINUE TO BE MOSTLY CLEAR WITH SOME SCT CUMULUS
DEVELOPMENT NORTH AND EAST ALONG THE RIM OF ARIZONA. EXPECTING
AFTERNOON THUNDERSTORMS TO REMAIN MOSTLY NORTH AND EAST OF PHOENIX
TERMINALS...HOWEVER COULD BE IN THE VICINITY OF KSDL. CONFIDENCE IS
LOW TO INCLUDE ANY MENTION IN ANY OF THE TAFS. OUTFLOW WINDS MAY
IMPACT PHOENIX AREA TERMINALS...BUT AGAIN CONFIDENCE IS LOW AS ALL
GUIDANCE DOES NOT LOOK FAVORABLE. SOUTHEAST CALIFORNIA WILL REMAIN
CLEAR SKIES AND MOSTLY LIGHT WINDS AT OR BELOW 10KTS THROUGH THE
PERIOD.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
DRIER AND WARMER WEATHER WILL GRADUALLY SPREAD INTO REGION FROM THE
WEST. A SLIGHT CHANCE OF AFTERNOON AND EVENING TSTMS WILL STILL BE
FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY. HIGH
TEMPERATURES THROUGH THE WEEK WILL BE NEAR NORMAL WITH HOTTER DESERT
LOCATIONS NEARING 110 ON MONDAY. MINIMUM HUMIDITIES WILL FALL INTO
THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY
ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES
REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST
WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS
EXPECTED.

&&

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...KUHLMAN/CB
AVIATION...DEWEY
FIRE WEATHER...DEWEY





000
FXUS65 KPSR 281650
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
950 AM MST FRI AUG 28 2015

.SYNOPSIS...
STRONG HIGH PRESSURE ALOFT WILL KEEP HIGH TEMPERATURES WELL ABOVE
SEASONAL NORMALS THROUGH SATURDAY WITH HOTTER LOWER DESERTS REACHING
OR EXCEEDING 110. THERE WILL BE SUFFICIENT MOISTURE EAST OF THE LOWER
COLORADO RIVER TO SUPPORT ISOLATED TO SCATTERED AFTERNOON AND EVENING
THUNDERSTORMS THROUGH SATURDAY. STARTING SUNDAY A DRIER SOUTHWEST
FLOW ALOFT WILL PUSH THE MOISTURE OFF TO THE EAST AND BY MONDAY STORM
CHANCES SHOULD BE CONFINED PRIMARILY TO HIGHER TERRAIN AREAS TO THE
EAST OF PHOENIX. THERE WILL BE A GRADUAL COOLING TREND STARTING
SUNDAY WITH CENTRAL DESERTS HIGH TEMPERATURES DROPPING TO AROUND
SEASONAL NORMALS BY THE MIDDLE OF NEXT WEEK.

&&

.DISCUSSION...
AFTER YESTERDAY`S ACTIVE MONSOON DAY...TODAY IS SHAPING UP TO BE
MUCH LESS ACTIVE. MOISTURE IS STILL PREVALENT AS MORNING RAOBS AND
SATELLITE DERIVED PWATS ARE STILL QUITE ELEVATED AT OR JUST ABOVE
1.50 INCHES. FLOW ALOFT CONTINUES TO BE WEAK...BUT HAS SHIFTED MORE
OUT OF THE NORTHWEST AND GUIDANCE INDICATES DECENT DRYING THROUGHOUT
THE DAY TODAY. THE BIGGEST INHIBITING FACTORS FOR WIDESPREAD SHOWERS
AND THUNDERSTORMS TODAY WILL BE THE DRYING NORTHWEST FLOW AND THE
MODESTLY WORKED OVER ATMOSPHERE FROM YESTERDAY`S ACTIVITY. AREA
TEMPERATURES ARE RUNNING ON AVERAGE 3-5 DEGREES COOLER THAN YESTERDAY
AND THUS NOT EXPECTING AN EARLY ONSET OF MOUNTAIN STORMS LIKE WE HAD
YESTERDAY. MID MORNING ML CAPES ARE HIGHEST OVER THE LOWER COLORADO
RIVER VALLEY WITH MUCH LESS INSTABILITY FROM PHOENIX EASTWARD.

CURRENT THINKING IS FIRST DEVELOPMENT WILL BE OVER HIGHER TERRAIN
AREAS OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA EARLY THIS
AFTERNOON AND THEN IN A MORE LIMITED CAPACITY OVER SOUTH-CENTRAL
ARIZONA. HI-RES MODEL OUTPUT SHOWS ONLY ISOLATED TO SCATTERED HIGH
TERRAIN ACTIVITY FOR THIS AFTERNOON WITH LITTLE TO NO STORMS OVER THE
LOWER DESERTS. POPS FOR TODAY ARE NEAR OR JUST ABOVE CLIMO AND MADE
SOME MINOR ADJUSTMENTS TO ADD IN SLIGHT CHANCES OVER HIGH TERRAIN
AREAS OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA WHILE LOWER POPS
OVER THE SOUTH-CENTRAL ARIZONA DESERTS. THE REST OF THE FORECAST
LOOKS TO BE IN GOOD SHAPE.

&&

.PREVIOUS DISCUSSION...
STRONG HIGH PRESSURE ALOFT REMAINS SITUATED ACROSS THE DESERT
SOUTHWEST THIS MORNING...WITH H5 HEIGHTS AROUND 594DM ACROSS THE
SOUTHERN DESERTS. THIS LED TO HOT TEMPERATURES OVER THE DESERTS
YESTERDAY WITH HIGHS REACHING 110 OVER THE HOTTER LOWER DESERTS.
DESPITE SOMEWHAT WEAK FLOW ALOFT...MOISTURE AND INSTABILITY WERE
SUFFICIENT YESTERDAY TO ALLOW FOR SCATTERED STRONG STORMS TO DEVELOP
ACROSS MUCH OF SOUTH CENTRAL ARIZONA. OUTFLOW BOUNDARY INTERACTIONS
WERE THE MAIN FORCING FEATURE FOR THE STRONG STORMS...NOT THE
PRESENCE OF A SIGNIFICANT INVERTED TROF/SHORT WAVE MOVING THROUGH THE
FLOW. YESTERDAYS CONVECTION ENDED LONG AGO AND AT 2 AM IR IMAGERY
SHOWED GENERALLY CLEAR SKIES FROM PHOENIX WESTWARD. SURFACE DEW
POINTS WERE ELEVATED AND WERE MOSTLY IN THE 60S WITH SOME LOW 70S
REPORTED.

THE TREND OF DRYING FROM THE WEST WILL BE PUT ON HOLD FOR THE NEXT
COUPLE OF DAYS OR SO...AND WE WILL BE LOOKING AT 2 MORE DAYS OF LOW
TO MODERATE GRADE MONSOON ACTIVITY ACROSS AREAS EAST OF THE LOWER
COLORADO RIVER. THE STRONG UPPER HIGH HAS BUILT WESTWARD A BIT AND
THE SOUTHWEST STEERING FLOW WILL BECOME MORE WEAK AND NONDESCRIPT
THROUGH SATURDAY...AS ARIZONA SITS UNDER THE CENTER OF THE STRONG
RIDGE. WITH MOISTURE REMAINING ELEVATED...PWAT VALUES ABOVE 1.5
INCHES IN MANY PLACES...PLENTY OF MLCAPE AVAILABLE...AND HIGH TEMPS
CLIMBING NEAR OF ABOVE 110 OVER THE HOTTER DESERTS...CONDITIONS ARE
SUITABLE FOR ISOLATED TO SCATTERED AFTERNOON AND EVENING STORMS
DEVELOPING TODAY AND SATURDAY. ONCE AGAIN...IT APPEARS THAT OUTFLOW
BOUNDARY INTERACTION WILL PLAY THE DOMINANT ROLE IN FORCING
CONVECTION AS MODELS DO NOT FORECAST ANY SIGNIFICANT
DISTURBANCES/INVERTED TROFS TO MOVE ACROSS THE AREA OVER THE NEXT 2
DAYS. POPS HAVE BEEN RAISED A BIT TODAY AND SATURDAY WILL STAY IN
THE SLIGHT CHANCE CATEGORY EAST OF THE LOWER CO RIVER...WITH CHANCE
VALUES OVER THE HIGHER TERRAIN EAST OF PHOENIX.

LATEST GFS AND ECMWF DETERMINISTIC GUIDANCE AS WELL AS ENSEMBLE
GUIDANCE REMAINS CONSISTENT IN CALLING FOR THE AFOREMENTIONED DRYING
TREND TO BEGIN SUNDAY AND CONTINUE THROUGH AT LEAST THE MIDDLE OF
NEXT WEEK. UPPER TROFFING IS FORECAST TO SET UP BOTH ALONG THE WEST
COAST AND INLAND OVER THE PAC NORTHWEST AND THIS WILL LEAD TO
STRENGTHENING SOUTHWEST FLOW ALOFT TO WORK INTO THE DESERT SOUTHWEST
AND GRADUALLY THIN OUT THE MOISTURE OVER SE CALIFORNIA AND THE LOWER
AZ DESERTS. BY NEXT MONDAY THUNDERSTORM CHANCES SHOULD BE CONFINED
PRIMARILY TO HIGHER TERRAIN AREAS EAST OF PHOENIX...ZONE 24 TO BE
EXACT. THERE WILL BE PERIODS OF HIGH CLOUDS MOVING THROUGH THE FLOW
BUT OVERALL DESERTS SHOULD RANGE FROM MOSTLY SUNNY TO PARTLY SUNNY
EACH DAY FROM MONDAY ONWARD. AS THE UPPER TROFFING DEVELOPS AND
HEIGHTS FALL...HIGH TEMPERATURES WILL STEADILY FALL OFF AND BY NEXT
MONDAY THE WARMER LOWER DESERTS WILL BE WELL UNDER 110. THE GREATER
PHOENIX AREA IS FORECAST TO DROP TO 105 ON MONDAY...AND EVENTUALLY
TO 103 ON WEDNESDAY AND THURSDAY. THE 103 DEGREE READINGS WILL EQUAL
THE CLIMATE NORMALS FOR THOSE DAYS.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND..
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

MOSTLY CLEAR SKIES AND LIGHT WINDS 10KT OR LESS EXPECTED AT ALL TAF
SITES. SKIES BECOME SCT-BKN AOA 10KFT ACROSS SOUTH-CENTRAL AZ...AND
THUNDERSTORM ACTIVITY WILL PICK UP AFTER 18Z OVER THE MOUNTAINS AND
HIGHER TERRAIN WELL EAST/NORTH OF PHOENIX...WITH SKIES REMAINING
MOSTLY CLEAR ACROSS SOUTHEAST CALIFORNIA. POSSIBLE FOR AN ISOLATED
STORM TO FORM OVER THE LOWER CENTRAL DESERTS AND GUSTY OUTFLOWS TO
IMPACT KPHX/KIWA/KSDL LATER THIS AFTERNOON AND EVENING.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...DRIER AND WARMER WEATHER WILL SPREAD INTO
REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...KUHLMAN
PREVIOUS DISCUSSION...CB
AVIATION...MEYERS
FIRE WEATHER...VASQUEZ





000
FXUS65 KPSR 281650
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
950 AM MST FRI AUG 28 2015

.SYNOPSIS...
STRONG HIGH PRESSURE ALOFT WILL KEEP HIGH TEMPERATURES WELL ABOVE
SEASONAL NORMALS THROUGH SATURDAY WITH HOTTER LOWER DESERTS REACHING
OR EXCEEDING 110. THERE WILL BE SUFFICIENT MOISTURE EAST OF THE LOWER
COLORADO RIVER TO SUPPORT ISOLATED TO SCATTERED AFTERNOON AND EVENING
THUNDERSTORMS THROUGH SATURDAY. STARTING SUNDAY A DRIER SOUTHWEST
FLOW ALOFT WILL PUSH THE MOISTURE OFF TO THE EAST AND BY MONDAY STORM
CHANCES SHOULD BE CONFINED PRIMARILY TO HIGHER TERRAIN AREAS TO THE
EAST OF PHOENIX. THERE WILL BE A GRADUAL COOLING TREND STARTING
SUNDAY WITH CENTRAL DESERTS HIGH TEMPERATURES DROPPING TO AROUND
SEASONAL NORMALS BY THE MIDDLE OF NEXT WEEK.

&&

.DISCUSSION...
AFTER YESTERDAY`S ACTIVE MONSOON DAY...TODAY IS SHAPING UP TO BE
MUCH LESS ACTIVE. MOISTURE IS STILL PREVALENT AS MORNING RAOBS AND
SATELLITE DERIVED PWATS ARE STILL QUITE ELEVATED AT OR JUST ABOVE
1.50 INCHES. FLOW ALOFT CONTINUES TO BE WEAK...BUT HAS SHIFTED MORE
OUT OF THE NORTHWEST AND GUIDANCE INDICATES DECENT DRYING THROUGHOUT
THE DAY TODAY. THE BIGGEST INHIBITING FACTORS FOR WIDESPREAD SHOWERS
AND THUNDERSTORMS TODAY WILL BE THE DRYING NORTHWEST FLOW AND THE
MODESTLY WORKED OVER ATMOSPHERE FROM YESTERDAY`S ACTIVITY. AREA
TEMPERATURES ARE RUNNING ON AVERAGE 3-5 DEGREES COOLER THAN YESTERDAY
AND THUS NOT EXPECTING AN EARLY ONSET OF MOUNTAIN STORMS LIKE WE HAD
YESTERDAY. MID MORNING ML CAPES ARE HIGHEST OVER THE LOWER COLORADO
RIVER VALLEY WITH MUCH LESS INSTABILITY FROM PHOENIX EASTWARD.

CURRENT THINKING IS FIRST DEVELOPMENT WILL BE OVER HIGHER TERRAIN
AREAS OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA EARLY THIS
AFTERNOON AND THEN IN A MORE LIMITED CAPACITY OVER SOUTH-CENTRAL
ARIZONA. HI-RES MODEL OUTPUT SHOWS ONLY ISOLATED TO SCATTERED HIGH
TERRAIN ACTIVITY FOR THIS AFTERNOON WITH LITTLE TO NO STORMS OVER THE
LOWER DESERTS. POPS FOR TODAY ARE NEAR OR JUST ABOVE CLIMO AND MADE
SOME MINOR ADJUSTMENTS TO ADD IN SLIGHT CHANCES OVER HIGH TERRAIN
AREAS OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA WHILE LOWER POPS
OVER THE SOUTH-CENTRAL ARIZONA DESERTS. THE REST OF THE FORECAST
LOOKS TO BE IN GOOD SHAPE.

&&

.PREVIOUS DISCUSSION...
STRONG HIGH PRESSURE ALOFT REMAINS SITUATED ACROSS THE DESERT
SOUTHWEST THIS MORNING...WITH H5 HEIGHTS AROUND 594DM ACROSS THE
SOUTHERN DESERTS. THIS LED TO HOT TEMPERATURES OVER THE DESERTS
YESTERDAY WITH HIGHS REACHING 110 OVER THE HOTTER LOWER DESERTS.
DESPITE SOMEWHAT WEAK FLOW ALOFT...MOISTURE AND INSTABILITY WERE
SUFFICIENT YESTERDAY TO ALLOW FOR SCATTERED STRONG STORMS TO DEVELOP
ACROSS MUCH OF SOUTH CENTRAL ARIZONA. OUTFLOW BOUNDARY INTERACTIONS
WERE THE MAIN FORCING FEATURE FOR THE STRONG STORMS...NOT THE
PRESENCE OF A SIGNIFICANT INVERTED TROF/SHORT WAVE MOVING THROUGH THE
FLOW. YESTERDAYS CONVECTION ENDED LONG AGO AND AT 2 AM IR IMAGERY
SHOWED GENERALLY CLEAR SKIES FROM PHOENIX WESTWARD. SURFACE DEW
POINTS WERE ELEVATED AND WERE MOSTLY IN THE 60S WITH SOME LOW 70S
REPORTED.

THE TREND OF DRYING FROM THE WEST WILL BE PUT ON HOLD FOR THE NEXT
COUPLE OF DAYS OR SO...AND WE WILL BE LOOKING AT 2 MORE DAYS OF LOW
TO MODERATE GRADE MONSOON ACTIVITY ACROSS AREAS EAST OF THE LOWER
COLORADO RIVER. THE STRONG UPPER HIGH HAS BUILT WESTWARD A BIT AND
THE SOUTHWEST STEERING FLOW WILL BECOME MORE WEAK AND NONDESCRIPT
THROUGH SATURDAY...AS ARIZONA SITS UNDER THE CENTER OF THE STRONG
RIDGE. WITH MOISTURE REMAINING ELEVATED...PWAT VALUES ABOVE 1.5
INCHES IN MANY PLACES...PLENTY OF MLCAPE AVAILABLE...AND HIGH TEMPS
CLIMBING NEAR OF ABOVE 110 OVER THE HOTTER DESERTS...CONDITIONS ARE
SUITABLE FOR ISOLATED TO SCATTERED AFTERNOON AND EVENING STORMS
DEVELOPING TODAY AND SATURDAY. ONCE AGAIN...IT APPEARS THAT OUTFLOW
BOUNDARY INTERACTION WILL PLAY THE DOMINANT ROLE IN FORCING
CONVECTION AS MODELS DO NOT FORECAST ANY SIGNIFICANT
DISTURBANCES/INVERTED TROFS TO MOVE ACROSS THE AREA OVER THE NEXT 2
DAYS. POPS HAVE BEEN RAISED A BIT TODAY AND SATURDAY WILL STAY IN
THE SLIGHT CHANCE CATEGORY EAST OF THE LOWER CO RIVER...WITH CHANCE
VALUES OVER THE HIGHER TERRAIN EAST OF PHOENIX.

LATEST GFS AND ECMWF DETERMINISTIC GUIDANCE AS WELL AS ENSEMBLE
GUIDANCE REMAINS CONSISTENT IN CALLING FOR THE AFOREMENTIONED DRYING
TREND TO BEGIN SUNDAY AND CONTINUE THROUGH AT LEAST THE MIDDLE OF
NEXT WEEK. UPPER TROFFING IS FORECAST TO SET UP BOTH ALONG THE WEST
COAST AND INLAND OVER THE PAC NORTHWEST AND THIS WILL LEAD TO
STRENGTHENING SOUTHWEST FLOW ALOFT TO WORK INTO THE DESERT SOUTHWEST
AND GRADUALLY THIN OUT THE MOISTURE OVER SE CALIFORNIA AND THE LOWER
AZ DESERTS. BY NEXT MONDAY THUNDERSTORM CHANCES SHOULD BE CONFINED
PRIMARILY TO HIGHER TERRAIN AREAS EAST OF PHOENIX...ZONE 24 TO BE
EXACT. THERE WILL BE PERIODS OF HIGH CLOUDS MOVING THROUGH THE FLOW
BUT OVERALL DESERTS SHOULD RANGE FROM MOSTLY SUNNY TO PARTLY SUNNY
EACH DAY FROM MONDAY ONWARD. AS THE UPPER TROFFING DEVELOPS AND
HEIGHTS FALL...HIGH TEMPERATURES WILL STEADILY FALL OFF AND BY NEXT
MONDAY THE WARMER LOWER DESERTS WILL BE WELL UNDER 110. THE GREATER
PHOENIX AREA IS FORECAST TO DROP TO 105 ON MONDAY...AND EVENTUALLY
TO 103 ON WEDNESDAY AND THURSDAY. THE 103 DEGREE READINGS WILL EQUAL
THE CLIMATE NORMALS FOR THOSE DAYS.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND..
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

MOSTLY CLEAR SKIES AND LIGHT WINDS 10KT OR LESS EXPECTED AT ALL TAF
SITES. SKIES BECOME SCT-BKN AOA 10KFT ACROSS SOUTH-CENTRAL AZ...AND
THUNDERSTORM ACTIVITY WILL PICK UP AFTER 18Z OVER THE MOUNTAINS AND
HIGHER TERRAIN WELL EAST/NORTH OF PHOENIX...WITH SKIES REMAINING
MOSTLY CLEAR ACROSS SOUTHEAST CALIFORNIA. POSSIBLE FOR AN ISOLATED
STORM TO FORM OVER THE LOWER CENTRAL DESERTS AND GUSTY OUTFLOWS TO
IMPACT KPHX/KIWA/KSDL LATER THIS AFTERNOON AND EVENING.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...DRIER AND WARMER WEATHER WILL SPREAD INTO
REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...KUHLMAN
PREVIOUS DISCUSSION...CB
AVIATION...MEYERS
FIRE WEATHER...VASQUEZ




000
FXUS65 KPSR 281650
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
950 AM MST FRI AUG 28 2015

.SYNOPSIS...
STRONG HIGH PRESSURE ALOFT WILL KEEP HIGH TEMPERATURES WELL ABOVE
SEASONAL NORMALS THROUGH SATURDAY WITH HOTTER LOWER DESERTS REACHING
OR EXCEEDING 110. THERE WILL BE SUFFICIENT MOISTURE EAST OF THE LOWER
COLORADO RIVER TO SUPPORT ISOLATED TO SCATTERED AFTERNOON AND EVENING
THUNDERSTORMS THROUGH SATURDAY. STARTING SUNDAY A DRIER SOUTHWEST
FLOW ALOFT WILL PUSH THE MOISTURE OFF TO THE EAST AND BY MONDAY STORM
CHANCES SHOULD BE CONFINED PRIMARILY TO HIGHER TERRAIN AREAS TO THE
EAST OF PHOENIX. THERE WILL BE A GRADUAL COOLING TREND STARTING
SUNDAY WITH CENTRAL DESERTS HIGH TEMPERATURES DROPPING TO AROUND
SEASONAL NORMALS BY THE MIDDLE OF NEXT WEEK.

&&

.DISCUSSION...
AFTER YESTERDAY`S ACTIVE MONSOON DAY...TODAY IS SHAPING UP TO BE
MUCH LESS ACTIVE. MOISTURE IS STILL PREVALENT AS MORNING RAOBS AND
SATELLITE DERIVED PWATS ARE STILL QUITE ELEVATED AT OR JUST ABOVE
1.50 INCHES. FLOW ALOFT CONTINUES TO BE WEAK...BUT HAS SHIFTED MORE
OUT OF THE NORTHWEST AND GUIDANCE INDICATES DECENT DRYING THROUGHOUT
THE DAY TODAY. THE BIGGEST INHIBITING FACTORS FOR WIDESPREAD SHOWERS
AND THUNDERSTORMS TODAY WILL BE THE DRYING NORTHWEST FLOW AND THE
MODESTLY WORKED OVER ATMOSPHERE FROM YESTERDAY`S ACTIVITY. AREA
TEMPERATURES ARE RUNNING ON AVERAGE 3-5 DEGREES COOLER THAN YESTERDAY
AND THUS NOT EXPECTING AN EARLY ONSET OF MOUNTAIN STORMS LIKE WE HAD
YESTERDAY. MID MORNING ML CAPES ARE HIGHEST OVER THE LOWER COLORADO
RIVER VALLEY WITH MUCH LESS INSTABILITY FROM PHOENIX EASTWARD.

CURRENT THINKING IS FIRST DEVELOPMENT WILL BE OVER HIGHER TERRAIN
AREAS OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA EARLY THIS
AFTERNOON AND THEN IN A MORE LIMITED CAPACITY OVER SOUTH-CENTRAL
ARIZONA. HI-RES MODEL OUTPUT SHOWS ONLY ISOLATED TO SCATTERED HIGH
TERRAIN ACTIVITY FOR THIS AFTERNOON WITH LITTLE TO NO STORMS OVER THE
LOWER DESERTS. POPS FOR TODAY ARE NEAR OR JUST ABOVE CLIMO AND MADE
SOME MINOR ADJUSTMENTS TO ADD IN SLIGHT CHANCES OVER HIGH TERRAIN
AREAS OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA WHILE LOWER POPS
OVER THE SOUTH-CENTRAL ARIZONA DESERTS. THE REST OF THE FORECAST
LOOKS TO BE IN GOOD SHAPE.

&&

.PREVIOUS DISCUSSION...
STRONG HIGH PRESSURE ALOFT REMAINS SITUATED ACROSS THE DESERT
SOUTHWEST THIS MORNING...WITH H5 HEIGHTS AROUND 594DM ACROSS THE
SOUTHERN DESERTS. THIS LED TO HOT TEMPERATURES OVER THE DESERTS
YESTERDAY WITH HIGHS REACHING 110 OVER THE HOTTER LOWER DESERTS.
DESPITE SOMEWHAT WEAK FLOW ALOFT...MOISTURE AND INSTABILITY WERE
SUFFICIENT YESTERDAY TO ALLOW FOR SCATTERED STRONG STORMS TO DEVELOP
ACROSS MUCH OF SOUTH CENTRAL ARIZONA. OUTFLOW BOUNDARY INTERACTIONS
WERE THE MAIN FORCING FEATURE FOR THE STRONG STORMS...NOT THE
PRESENCE OF A SIGNIFICANT INVERTED TROF/SHORT WAVE MOVING THROUGH THE
FLOW. YESTERDAYS CONVECTION ENDED LONG AGO AND AT 2 AM IR IMAGERY
SHOWED GENERALLY CLEAR SKIES FROM PHOENIX WESTWARD. SURFACE DEW
POINTS WERE ELEVATED AND WERE MOSTLY IN THE 60S WITH SOME LOW 70S
REPORTED.

THE TREND OF DRYING FROM THE WEST WILL BE PUT ON HOLD FOR THE NEXT
COUPLE OF DAYS OR SO...AND WE WILL BE LOOKING AT 2 MORE DAYS OF LOW
TO MODERATE GRADE MONSOON ACTIVITY ACROSS AREAS EAST OF THE LOWER
COLORADO RIVER. THE STRONG UPPER HIGH HAS BUILT WESTWARD A BIT AND
THE SOUTHWEST STEERING FLOW WILL BECOME MORE WEAK AND NONDESCRIPT
THROUGH SATURDAY...AS ARIZONA SITS UNDER THE CENTER OF THE STRONG
RIDGE. WITH MOISTURE REMAINING ELEVATED...PWAT VALUES ABOVE 1.5
INCHES IN MANY PLACES...PLENTY OF MLCAPE AVAILABLE...AND HIGH TEMPS
CLIMBING NEAR OF ABOVE 110 OVER THE HOTTER DESERTS...CONDITIONS ARE
SUITABLE FOR ISOLATED TO SCATTERED AFTERNOON AND EVENING STORMS
DEVELOPING TODAY AND SATURDAY. ONCE AGAIN...IT APPEARS THAT OUTFLOW
BOUNDARY INTERACTION WILL PLAY THE DOMINANT ROLE IN FORCING
CONVECTION AS MODELS DO NOT FORECAST ANY SIGNIFICANT
DISTURBANCES/INVERTED TROFS TO MOVE ACROSS THE AREA OVER THE NEXT 2
DAYS. POPS HAVE BEEN RAISED A BIT TODAY AND SATURDAY WILL STAY IN
THE SLIGHT CHANCE CATEGORY EAST OF THE LOWER CO RIVER...WITH CHANCE
VALUES OVER THE HIGHER TERRAIN EAST OF PHOENIX.

LATEST GFS AND ECMWF DETERMINISTIC GUIDANCE AS WELL AS ENSEMBLE
GUIDANCE REMAINS CONSISTENT IN CALLING FOR THE AFOREMENTIONED DRYING
TREND TO BEGIN SUNDAY AND CONTINUE THROUGH AT LEAST THE MIDDLE OF
NEXT WEEK. UPPER TROFFING IS FORECAST TO SET UP BOTH ALONG THE WEST
COAST AND INLAND OVER THE PAC NORTHWEST AND THIS WILL LEAD TO
STRENGTHENING SOUTHWEST FLOW ALOFT TO WORK INTO THE DESERT SOUTHWEST
AND GRADUALLY THIN OUT THE MOISTURE OVER SE CALIFORNIA AND THE LOWER
AZ DESERTS. BY NEXT MONDAY THUNDERSTORM CHANCES SHOULD BE CONFINED
PRIMARILY TO HIGHER TERRAIN AREAS EAST OF PHOENIX...ZONE 24 TO BE
EXACT. THERE WILL BE PERIODS OF HIGH CLOUDS MOVING THROUGH THE FLOW
BUT OVERALL DESERTS SHOULD RANGE FROM MOSTLY SUNNY TO PARTLY SUNNY
EACH DAY FROM MONDAY ONWARD. AS THE UPPER TROFFING DEVELOPS AND
HEIGHTS FALL...HIGH TEMPERATURES WILL STEADILY FALL OFF AND BY NEXT
MONDAY THE WARMER LOWER DESERTS WILL BE WELL UNDER 110. THE GREATER
PHOENIX AREA IS FORECAST TO DROP TO 105 ON MONDAY...AND EVENTUALLY
TO 103 ON WEDNESDAY AND THURSDAY. THE 103 DEGREE READINGS WILL EQUAL
THE CLIMATE NORMALS FOR THOSE DAYS.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND..
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

MOSTLY CLEAR SKIES AND LIGHT WINDS 10KT OR LESS EXPECTED AT ALL TAF
SITES. SKIES BECOME SCT-BKN AOA 10KFT ACROSS SOUTH-CENTRAL AZ...AND
THUNDERSTORM ACTIVITY WILL PICK UP AFTER 18Z OVER THE MOUNTAINS AND
HIGHER TERRAIN WELL EAST/NORTH OF PHOENIX...WITH SKIES REMAINING
MOSTLY CLEAR ACROSS SOUTHEAST CALIFORNIA. POSSIBLE FOR AN ISOLATED
STORM TO FORM OVER THE LOWER CENTRAL DESERTS AND GUSTY OUTFLOWS TO
IMPACT KPHX/KIWA/KSDL LATER THIS AFTERNOON AND EVENING.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...DRIER AND WARMER WEATHER WILL SPREAD INTO
REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...KUHLMAN
PREVIOUS DISCUSSION...CB
AVIATION...MEYERS
FIRE WEATHER...VASQUEZ





000
FXUS65 KPSR 281650
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
950 AM MST FRI AUG 28 2015

.SYNOPSIS...
STRONG HIGH PRESSURE ALOFT WILL KEEP HIGH TEMPERATURES WELL ABOVE
SEASONAL NORMALS THROUGH SATURDAY WITH HOTTER LOWER DESERTS REACHING
OR EXCEEDING 110. THERE WILL BE SUFFICIENT MOISTURE EAST OF THE LOWER
COLORADO RIVER TO SUPPORT ISOLATED TO SCATTERED AFTERNOON AND EVENING
THUNDERSTORMS THROUGH SATURDAY. STARTING SUNDAY A DRIER SOUTHWEST
FLOW ALOFT WILL PUSH THE MOISTURE OFF TO THE EAST AND BY MONDAY STORM
CHANCES SHOULD BE CONFINED PRIMARILY TO HIGHER TERRAIN AREAS TO THE
EAST OF PHOENIX. THERE WILL BE A GRADUAL COOLING TREND STARTING
SUNDAY WITH CENTRAL DESERTS HIGH TEMPERATURES DROPPING TO AROUND
SEASONAL NORMALS BY THE MIDDLE OF NEXT WEEK.

&&

.DISCUSSION...
AFTER YESTERDAY`S ACTIVE MONSOON DAY...TODAY IS SHAPING UP TO BE
MUCH LESS ACTIVE. MOISTURE IS STILL PREVALENT AS MORNING RAOBS AND
SATELLITE DERIVED PWATS ARE STILL QUITE ELEVATED AT OR JUST ABOVE
1.50 INCHES. FLOW ALOFT CONTINUES TO BE WEAK...BUT HAS SHIFTED MORE
OUT OF THE NORTHWEST AND GUIDANCE INDICATES DECENT DRYING THROUGHOUT
THE DAY TODAY. THE BIGGEST INHIBITING FACTORS FOR WIDESPREAD SHOWERS
AND THUNDERSTORMS TODAY WILL BE THE DRYING NORTHWEST FLOW AND THE
MODESTLY WORKED OVER ATMOSPHERE FROM YESTERDAY`S ACTIVITY. AREA
TEMPERATURES ARE RUNNING ON AVERAGE 3-5 DEGREES COOLER THAN YESTERDAY
AND THUS NOT EXPECTING AN EARLY ONSET OF MOUNTAIN STORMS LIKE WE HAD
YESTERDAY. MID MORNING ML CAPES ARE HIGHEST OVER THE LOWER COLORADO
RIVER VALLEY WITH MUCH LESS INSTABILITY FROM PHOENIX EASTWARD.

CURRENT THINKING IS FIRST DEVELOPMENT WILL BE OVER HIGHER TERRAIN
AREAS OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA EARLY THIS
AFTERNOON AND THEN IN A MORE LIMITED CAPACITY OVER SOUTH-CENTRAL
ARIZONA. HI-RES MODEL OUTPUT SHOWS ONLY ISOLATED TO SCATTERED HIGH
TERRAIN ACTIVITY FOR THIS AFTERNOON WITH LITTLE TO NO STORMS OVER THE
LOWER DESERTS. POPS FOR TODAY ARE NEAR OR JUST ABOVE CLIMO AND MADE
SOME MINOR ADJUSTMENTS TO ADD IN SLIGHT CHANCES OVER HIGH TERRAIN
AREAS OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA WHILE LOWER POPS
OVER THE SOUTH-CENTRAL ARIZONA DESERTS. THE REST OF THE FORECAST
LOOKS TO BE IN GOOD SHAPE.

&&

.PREVIOUS DISCUSSION...
STRONG HIGH PRESSURE ALOFT REMAINS SITUATED ACROSS THE DESERT
SOUTHWEST THIS MORNING...WITH H5 HEIGHTS AROUND 594DM ACROSS THE
SOUTHERN DESERTS. THIS LED TO HOT TEMPERATURES OVER THE DESERTS
YESTERDAY WITH HIGHS REACHING 110 OVER THE HOTTER LOWER DESERTS.
DESPITE SOMEWHAT WEAK FLOW ALOFT...MOISTURE AND INSTABILITY WERE
SUFFICIENT YESTERDAY TO ALLOW FOR SCATTERED STRONG STORMS TO DEVELOP
ACROSS MUCH OF SOUTH CENTRAL ARIZONA. OUTFLOW BOUNDARY INTERACTIONS
WERE THE MAIN FORCING FEATURE FOR THE STRONG STORMS...NOT THE
PRESENCE OF A SIGNIFICANT INVERTED TROF/SHORT WAVE MOVING THROUGH THE
FLOW. YESTERDAYS CONVECTION ENDED LONG AGO AND AT 2 AM IR IMAGERY
SHOWED GENERALLY CLEAR SKIES FROM PHOENIX WESTWARD. SURFACE DEW
POINTS WERE ELEVATED AND WERE MOSTLY IN THE 60S WITH SOME LOW 70S
REPORTED.

THE TREND OF DRYING FROM THE WEST WILL BE PUT ON HOLD FOR THE NEXT
COUPLE OF DAYS OR SO...AND WE WILL BE LOOKING AT 2 MORE DAYS OF LOW
TO MODERATE GRADE MONSOON ACTIVITY ACROSS AREAS EAST OF THE LOWER
COLORADO RIVER. THE STRONG UPPER HIGH HAS BUILT WESTWARD A BIT AND
THE SOUTHWEST STEERING FLOW WILL BECOME MORE WEAK AND NONDESCRIPT
THROUGH SATURDAY...AS ARIZONA SITS UNDER THE CENTER OF THE STRONG
RIDGE. WITH MOISTURE REMAINING ELEVATED...PWAT VALUES ABOVE 1.5
INCHES IN MANY PLACES...PLENTY OF MLCAPE AVAILABLE...AND HIGH TEMPS
CLIMBING NEAR OF ABOVE 110 OVER THE HOTTER DESERTS...CONDITIONS ARE
SUITABLE FOR ISOLATED TO SCATTERED AFTERNOON AND EVENING STORMS
DEVELOPING TODAY AND SATURDAY. ONCE AGAIN...IT APPEARS THAT OUTFLOW
BOUNDARY INTERACTION WILL PLAY THE DOMINANT ROLE IN FORCING
CONVECTION AS MODELS DO NOT FORECAST ANY SIGNIFICANT
DISTURBANCES/INVERTED TROFS TO MOVE ACROSS THE AREA OVER THE NEXT 2
DAYS. POPS HAVE BEEN RAISED A BIT TODAY AND SATURDAY WILL STAY IN
THE SLIGHT CHANCE CATEGORY EAST OF THE LOWER CO RIVER...WITH CHANCE
VALUES OVER THE HIGHER TERRAIN EAST OF PHOENIX.

LATEST GFS AND ECMWF DETERMINISTIC GUIDANCE AS WELL AS ENSEMBLE
GUIDANCE REMAINS CONSISTENT IN CALLING FOR THE AFOREMENTIONED DRYING
TREND TO BEGIN SUNDAY AND CONTINUE THROUGH AT LEAST THE MIDDLE OF
NEXT WEEK. UPPER TROFFING IS FORECAST TO SET UP BOTH ALONG THE WEST
COAST AND INLAND OVER THE PAC NORTHWEST AND THIS WILL LEAD TO
STRENGTHENING SOUTHWEST FLOW ALOFT TO WORK INTO THE DESERT SOUTHWEST
AND GRADUALLY THIN OUT THE MOISTURE OVER SE CALIFORNIA AND THE LOWER
AZ DESERTS. BY NEXT MONDAY THUNDERSTORM CHANCES SHOULD BE CONFINED
PRIMARILY TO HIGHER TERRAIN AREAS EAST OF PHOENIX...ZONE 24 TO BE
EXACT. THERE WILL BE PERIODS OF HIGH CLOUDS MOVING THROUGH THE FLOW
BUT OVERALL DESERTS SHOULD RANGE FROM MOSTLY SUNNY TO PARTLY SUNNY
EACH DAY FROM MONDAY ONWARD. AS THE UPPER TROFFING DEVELOPS AND
HEIGHTS FALL...HIGH TEMPERATURES WILL STEADILY FALL OFF AND BY NEXT
MONDAY THE WARMER LOWER DESERTS WILL BE WELL UNDER 110. THE GREATER
PHOENIX AREA IS FORECAST TO DROP TO 105 ON MONDAY...AND EVENTUALLY
TO 103 ON WEDNESDAY AND THURSDAY. THE 103 DEGREE READINGS WILL EQUAL
THE CLIMATE NORMALS FOR THOSE DAYS.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND..
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

MOSTLY CLEAR SKIES AND LIGHT WINDS 10KT OR LESS EXPECTED AT ALL TAF
SITES. SKIES BECOME SCT-BKN AOA 10KFT ACROSS SOUTH-CENTRAL AZ...AND
THUNDERSTORM ACTIVITY WILL PICK UP AFTER 18Z OVER THE MOUNTAINS AND
HIGHER TERRAIN WELL EAST/NORTH OF PHOENIX...WITH SKIES REMAINING
MOSTLY CLEAR ACROSS SOUTHEAST CALIFORNIA. POSSIBLE FOR AN ISOLATED
STORM TO FORM OVER THE LOWER CENTRAL DESERTS AND GUSTY OUTFLOWS TO
IMPACT KPHX/KIWA/KSDL LATER THIS AFTERNOON AND EVENING.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...DRIER AND WARMER WEATHER WILL SPREAD INTO
REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...KUHLMAN
PREVIOUS DISCUSSION...CB
AVIATION...MEYERS
FIRE WEATHER...VASQUEZ




000
FXUS65 KPSR 281233 AAA
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
530 AM MST FRI AUG 28 2015

.UPDATE...UPDATED AVIATION DISCUSSION.

&&

.SYNOPSIS... STRONG HIGH PRESSURE ALOFT WILL KEEP HIGH TEMPERATURES
WELL ABOVE SEASONAL NORMALS THROUGH SATURDAY WITH HOTTER LOWER
DESERTS REACHING OR EXCEEDING 110. THERE WILL BE SUFFICIENT MOISTURE
EAST OF THE LOWER COLORADO RIVER TO SUPPORT ISOLATED TO SCATTERED
AFTERNOON AND EVENING THUNDERSTORMS THROUGH SATURDAY. STARTING
SUNDAY A DRIER SOUTHWEST FLOW ALOFT WILL PUSH THE MOISTURE OFF TO
THE EAST AND BY MONDAY STORM CHANCES SHOULD BE CONFINED PRIMARILY TO
HIGHER TERRAIN AREAS TO THE EAST OF PHOENIX. THERE WILL BE A GRADUAL
COOLING TREND STARTING SUNDAY WITH CENTRAL DESERTS HIGH TEMPERATURES
DROPPING TO AROUND SEASONAL NORMALS BY THE MIDDLE OF NEXT WEEK.

&&

.DISCUSSION... STRONG HIGH PRESSURE ALOFT REMAINS SITUATED ACROSS
THE DESERT SOUTHWEST THIS MORNING...WITH H5 HEIGHTS AROUND 594DM
ACROSS THE SOUTHERN DESERTS. THIS LED TO HOT TEMPERATURES OVER THE
DESERTS YESTERDAY WITH HIGHS REACHING 110 OVER THE HOTTER LOWER
DESERTS. DESPITE SOMEWHAT WEAK FLOW ALOFT...MOISTURE AND INSTABILITY
WERE SUFFICIENT YESTERDAY TO ALLOW FOR SCATTERED STRONG STORMS TO
DEVELOP ACROSS MUCH OF SOUTH CENTRAL ARIZONA. OUTFLOW BOUNDARY
INTERACTIONS WERE THE MAIN FORCING FEATURE FOR THE STRONG
STORMS...NOT THE PRESENCE OF A SIGNIFICANT INVERTED TROF/SHORT WAVE
MOVING THROUGH THE FLOW. YESTERDAYS CONVECTION ENDED LONG AGO AND AT
2 AM IR IMAGERY SHOWED GENERALLY CLEAR SKIES FROM PHOENIX WESTWARD.
SURFACE DEW POINTS WERE ELEVATED AND WERE MOSTLY IN THE 60S WITH SOME
LOW 70S REPORTED.

THE TREND OF DRYING FROM THE WEST WILL BE PUT ON HOLD FOR THE NEXT
COUPLE OF DAYS OR SO...AND WE WILL BE LOOKING AT 2 MORE DAYS OF LOW
TO MODERATE GRADE MONSOON ACTIVITY ACROSS AREAS EAST OF THE LOWER
COLORADO RIVER. THE STRONG UPPER HIGH HAS BUILT WESTWARD A BIT AND
THE SOUTHWEST STEERING FLOW WILL BECOME MORE WEAK AND NONDESCRIPT
THROUGH SATURDAY...AS ARIZONA SITS UNDER THE CENTER OF THE STRONG
RIDGE. WITH MOISTURE REMAINING ELEVATED...PWAT VALUES ABOVE 1.5
INCHES IN MANY PLACES...PLENTY OF MLCAPE AVAILABLE...AND HIGH TEMPS
CLIMBING NEAR OF ABOVE 110 OVER THE HOTTER DESERTS...CONDITIONS ARE
SUITABLE FOR ISOLATED TO SCATTERED AFTERNOON AND EVENING STORMS
DEVELOPING TODAY AND SATURDAY. ONCE AGAIN...IT APPEARS THAT OUTFLOW
BOUNDARY INTERACTION WILL PLAY THE DOMINANT ROLE IN FORCING
CONVECTION AS MODELS DO NOT FORECAST ANY SIGNIFICANT
DISTURBANCES/INVERTED TROFS TO MOVE ACROSS THE AREA OVER THE NEXT 2
DAYS. POPS HAVE BEEN RAISED A BIT TODAY AND SATURDAY WILL STAY IN
THE SLIGHT CHANCE CATEGORY EAST OF THE LOWER CO RIVER...WITH CHANCE
VALUES OVER THE HIGHER TERRAIN EAST OF PHOENIX.

LATEST GFS AND ECMWF DETERMINISTIC GUIDANCE AS WELL AS ENSEMBLE
GUIDANCE REMAINS CONSISTENT IN CALLING FOR THE AFOREMENTIONED DRYING
TREND TO BEGIN SUNDAY AND CONTINUE THROUGH AT LEAST THE MIDDLE OF
NEXT WEEK. UPPER TROFFING IS FORECAST TO SET UP BOTH ALONG THE WEST
COAST AND INLAND OVER THE PAC NORTHWEST AND THIS WILL LEAD TO
STRENGTHENING SOUTHWEST FLOW ALOFT TO WORK INTO THE DESERT SOUTHWEST
AND GRADUALLY THIN OUT THE MOISTURE OVER SE CALIFORNIA AND THE LOWER
AZ DESERTS. BY NEXT MONDAY THUNDERSTORM CHANCES SHOULD BE CONFINED
PRIMARILY TO HIGHER TERRAIN AREAS EAST OF PHOENIX...ZONE 24 TO BE
EXACT. THERE WILL BE PERIODS OF HIGH CLOUDS MOVING THROUGH THE FLOW
BUT OVERALL DESERTS SHOULD RANGE FROM MOSTLY SUNNY TO PARTLY SUNNY
EACH DAY FROM MONDAY ONWARD. AS THE UPPER TROFFING DEVELOPS AND
HEIGHTS FALL...HIGH TEMPERATURES WILL STEADILY FALL OFF AND BY NEXT
MONDAY THE WARMER LOWER DESERTS WILL BE WELL UNDER 110. THE GREATER
PHOENIX AREA IS FORECAST TO DROP TO 105 ON MONDAY...AND EVENTUALLY
TO 103 ON WEDNESDAY AND THURSDAY. THE 103 DEGREE READINGS WILL EQUAL
THE CLIMATE NORMALS FOR THOSE DAYS.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND..
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

MOSTLY CLEAR SKIES AND LIGHT WINDS 10KT OR LESS EXPECTED AT ALL TAF
SITES. SKIES BECOME SCT-BKN AOA 10KFT ACROSS SOUTH-CENTRAL AZ...AND
THUNDERSTORM ACTIVITY WILL PICK UP AFTER 18Z OVER THE MOUNTAINS AND
HIGHER TERRAIN WELL EAST/NORTH OF PHOENIX...WITH SKIES REMAINING
MOSTLY CLEAR ACROSS SOUTHEAST CALIFORNIA. POSSIBLE FOR AN ISOLATED
STORM TO FORM OVER THE LOWER CENTRAL DESERTS AND GUSTY OUTFLOWS TO
IMPACT KPHX/KIWA/KSDL LATER THIS AFTERNOON AND EVENING.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...DRIER AND WARMER WEATHER WILL SPREAD INTO
REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...CB
AVIATION...MEYERS
FIRE WEATHER...VASQUEZ





000
FXUS65 KPSR 281233 AAA
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
530 AM MST FRI AUG 28 2015

.UPDATE...UPDATED AVIATION DISCUSSION.

&&

.SYNOPSIS... STRONG HIGH PRESSURE ALOFT WILL KEEP HIGH TEMPERATURES
WELL ABOVE SEASONAL NORMALS THROUGH SATURDAY WITH HOTTER LOWER
DESERTS REACHING OR EXCEEDING 110. THERE WILL BE SUFFICIENT MOISTURE
EAST OF THE LOWER COLORADO RIVER TO SUPPORT ISOLATED TO SCATTERED
AFTERNOON AND EVENING THUNDERSTORMS THROUGH SATURDAY. STARTING
SUNDAY A DRIER SOUTHWEST FLOW ALOFT WILL PUSH THE MOISTURE OFF TO
THE EAST AND BY MONDAY STORM CHANCES SHOULD BE CONFINED PRIMARILY TO
HIGHER TERRAIN AREAS TO THE EAST OF PHOENIX. THERE WILL BE A GRADUAL
COOLING TREND STARTING SUNDAY WITH CENTRAL DESERTS HIGH TEMPERATURES
DROPPING TO AROUND SEASONAL NORMALS BY THE MIDDLE OF NEXT WEEK.

&&

.DISCUSSION... STRONG HIGH PRESSURE ALOFT REMAINS SITUATED ACROSS
THE DESERT SOUTHWEST THIS MORNING...WITH H5 HEIGHTS AROUND 594DM
ACROSS THE SOUTHERN DESERTS. THIS LED TO HOT TEMPERATURES OVER THE
DESERTS YESTERDAY WITH HIGHS REACHING 110 OVER THE HOTTER LOWER
DESERTS. DESPITE SOMEWHAT WEAK FLOW ALOFT...MOISTURE AND INSTABILITY
WERE SUFFICIENT YESTERDAY TO ALLOW FOR SCATTERED STRONG STORMS TO
DEVELOP ACROSS MUCH OF SOUTH CENTRAL ARIZONA. OUTFLOW BOUNDARY
INTERACTIONS WERE THE MAIN FORCING FEATURE FOR THE STRONG
STORMS...NOT THE PRESENCE OF A SIGNIFICANT INVERTED TROF/SHORT WAVE
MOVING THROUGH THE FLOW. YESTERDAYS CONVECTION ENDED LONG AGO AND AT
2 AM IR IMAGERY SHOWED GENERALLY CLEAR SKIES FROM PHOENIX WESTWARD.
SURFACE DEW POINTS WERE ELEVATED AND WERE MOSTLY IN THE 60S WITH SOME
LOW 70S REPORTED.

THE TREND OF DRYING FROM THE WEST WILL BE PUT ON HOLD FOR THE NEXT
COUPLE OF DAYS OR SO...AND WE WILL BE LOOKING AT 2 MORE DAYS OF LOW
TO MODERATE GRADE MONSOON ACTIVITY ACROSS AREAS EAST OF THE LOWER
COLORADO RIVER. THE STRONG UPPER HIGH HAS BUILT WESTWARD A BIT AND
THE SOUTHWEST STEERING FLOW WILL BECOME MORE WEAK AND NONDESCRIPT
THROUGH SATURDAY...AS ARIZONA SITS UNDER THE CENTER OF THE STRONG
RIDGE. WITH MOISTURE REMAINING ELEVATED...PWAT VALUES ABOVE 1.5
INCHES IN MANY PLACES...PLENTY OF MLCAPE AVAILABLE...AND HIGH TEMPS
CLIMBING NEAR OF ABOVE 110 OVER THE HOTTER DESERTS...CONDITIONS ARE
SUITABLE FOR ISOLATED TO SCATTERED AFTERNOON AND EVENING STORMS
DEVELOPING TODAY AND SATURDAY. ONCE AGAIN...IT APPEARS THAT OUTFLOW
BOUNDARY INTERACTION WILL PLAY THE DOMINANT ROLE IN FORCING
CONVECTION AS MODELS DO NOT FORECAST ANY SIGNIFICANT
DISTURBANCES/INVERTED TROFS TO MOVE ACROSS THE AREA OVER THE NEXT 2
DAYS. POPS HAVE BEEN RAISED A BIT TODAY AND SATURDAY WILL STAY IN
THE SLIGHT CHANCE CATEGORY EAST OF THE LOWER CO RIVER...WITH CHANCE
VALUES OVER THE HIGHER TERRAIN EAST OF PHOENIX.

LATEST GFS AND ECMWF DETERMINISTIC GUIDANCE AS WELL AS ENSEMBLE
GUIDANCE REMAINS CONSISTENT IN CALLING FOR THE AFOREMENTIONED DRYING
TREND TO BEGIN SUNDAY AND CONTINUE THROUGH AT LEAST THE MIDDLE OF
NEXT WEEK. UPPER TROFFING IS FORECAST TO SET UP BOTH ALONG THE WEST
COAST AND INLAND OVER THE PAC NORTHWEST AND THIS WILL LEAD TO
STRENGTHENING SOUTHWEST FLOW ALOFT TO WORK INTO THE DESERT SOUTHWEST
AND GRADUALLY THIN OUT THE MOISTURE OVER SE CALIFORNIA AND THE LOWER
AZ DESERTS. BY NEXT MONDAY THUNDERSTORM CHANCES SHOULD BE CONFINED
PRIMARILY TO HIGHER TERRAIN AREAS EAST OF PHOENIX...ZONE 24 TO BE
EXACT. THERE WILL BE PERIODS OF HIGH CLOUDS MOVING THROUGH THE FLOW
BUT OVERALL DESERTS SHOULD RANGE FROM MOSTLY SUNNY TO PARTLY SUNNY
EACH DAY FROM MONDAY ONWARD. AS THE UPPER TROFFING DEVELOPS AND
HEIGHTS FALL...HIGH TEMPERATURES WILL STEADILY FALL OFF AND BY NEXT
MONDAY THE WARMER LOWER DESERTS WILL BE WELL UNDER 110. THE GREATER
PHOENIX AREA IS FORECAST TO DROP TO 105 ON MONDAY...AND EVENTUALLY
TO 103 ON WEDNESDAY AND THURSDAY. THE 103 DEGREE READINGS WILL EQUAL
THE CLIMATE NORMALS FOR THOSE DAYS.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND..
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

MOSTLY CLEAR SKIES AND LIGHT WINDS 10KT OR LESS EXPECTED AT ALL TAF
SITES. SKIES BECOME SCT-BKN AOA 10KFT ACROSS SOUTH-CENTRAL AZ...AND
THUNDERSTORM ACTIVITY WILL PICK UP AFTER 18Z OVER THE MOUNTAINS AND
HIGHER TERRAIN WELL EAST/NORTH OF PHOENIX...WITH SKIES REMAINING
MOSTLY CLEAR ACROSS SOUTHEAST CALIFORNIA. POSSIBLE FOR AN ISOLATED
STORM TO FORM OVER THE LOWER CENTRAL DESERTS AND GUSTY OUTFLOWS TO
IMPACT KPHX/KIWA/KSDL LATER THIS AFTERNOON AND EVENING.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...DRIER AND WARMER WEATHER WILL SPREAD INTO
REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...CB
AVIATION...MEYERS
FIRE WEATHER...VASQUEZ




000
FXUS65 KPSR 281233 AAA
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
530 AM MST FRI AUG 28 2015

.UPDATE...UPDATED AVIATION DISCUSSION.

&&

.SYNOPSIS... STRONG HIGH PRESSURE ALOFT WILL KEEP HIGH TEMPERATURES
WELL ABOVE SEASONAL NORMALS THROUGH SATURDAY WITH HOTTER LOWER
DESERTS REACHING OR EXCEEDING 110. THERE WILL BE SUFFICIENT MOISTURE
EAST OF THE LOWER COLORADO RIVER TO SUPPORT ISOLATED TO SCATTERED
AFTERNOON AND EVENING THUNDERSTORMS THROUGH SATURDAY. STARTING
SUNDAY A DRIER SOUTHWEST FLOW ALOFT WILL PUSH THE MOISTURE OFF TO
THE EAST AND BY MONDAY STORM CHANCES SHOULD BE CONFINED PRIMARILY TO
HIGHER TERRAIN AREAS TO THE EAST OF PHOENIX. THERE WILL BE A GRADUAL
COOLING TREND STARTING SUNDAY WITH CENTRAL DESERTS HIGH TEMPERATURES
DROPPING TO AROUND SEASONAL NORMALS BY THE MIDDLE OF NEXT WEEK.

&&

.DISCUSSION... STRONG HIGH PRESSURE ALOFT REMAINS SITUATED ACROSS
THE DESERT SOUTHWEST THIS MORNING...WITH H5 HEIGHTS AROUND 594DM
ACROSS THE SOUTHERN DESERTS. THIS LED TO HOT TEMPERATURES OVER THE
DESERTS YESTERDAY WITH HIGHS REACHING 110 OVER THE HOTTER LOWER
DESERTS. DESPITE SOMEWHAT WEAK FLOW ALOFT...MOISTURE AND INSTABILITY
WERE SUFFICIENT YESTERDAY TO ALLOW FOR SCATTERED STRONG STORMS TO
DEVELOP ACROSS MUCH OF SOUTH CENTRAL ARIZONA. OUTFLOW BOUNDARY
INTERACTIONS WERE THE MAIN FORCING FEATURE FOR THE STRONG
STORMS...NOT THE PRESENCE OF A SIGNIFICANT INVERTED TROF/SHORT WAVE
MOVING THROUGH THE FLOW. YESTERDAYS CONVECTION ENDED LONG AGO AND AT
2 AM IR IMAGERY SHOWED GENERALLY CLEAR SKIES FROM PHOENIX WESTWARD.
SURFACE DEW POINTS WERE ELEVATED AND WERE MOSTLY IN THE 60S WITH SOME
LOW 70S REPORTED.

THE TREND OF DRYING FROM THE WEST WILL BE PUT ON HOLD FOR THE NEXT
COUPLE OF DAYS OR SO...AND WE WILL BE LOOKING AT 2 MORE DAYS OF LOW
TO MODERATE GRADE MONSOON ACTIVITY ACROSS AREAS EAST OF THE LOWER
COLORADO RIVER. THE STRONG UPPER HIGH HAS BUILT WESTWARD A BIT AND
THE SOUTHWEST STEERING FLOW WILL BECOME MORE WEAK AND NONDESCRIPT
THROUGH SATURDAY...AS ARIZONA SITS UNDER THE CENTER OF THE STRONG
RIDGE. WITH MOISTURE REMAINING ELEVATED...PWAT VALUES ABOVE 1.5
INCHES IN MANY PLACES...PLENTY OF MLCAPE AVAILABLE...AND HIGH TEMPS
CLIMBING NEAR OF ABOVE 110 OVER THE HOTTER DESERTS...CONDITIONS ARE
SUITABLE FOR ISOLATED TO SCATTERED AFTERNOON AND EVENING STORMS
DEVELOPING TODAY AND SATURDAY. ONCE AGAIN...IT APPEARS THAT OUTFLOW
BOUNDARY INTERACTION WILL PLAY THE DOMINANT ROLE IN FORCING
CONVECTION AS MODELS DO NOT FORECAST ANY SIGNIFICANT
DISTURBANCES/INVERTED TROFS TO MOVE ACROSS THE AREA OVER THE NEXT 2
DAYS. POPS HAVE BEEN RAISED A BIT TODAY AND SATURDAY WILL STAY IN
THE SLIGHT CHANCE CATEGORY EAST OF THE LOWER CO RIVER...WITH CHANCE
VALUES OVER THE HIGHER TERRAIN EAST OF PHOENIX.

LATEST GFS AND ECMWF DETERMINISTIC GUIDANCE AS WELL AS ENSEMBLE
GUIDANCE REMAINS CONSISTENT IN CALLING FOR THE AFOREMENTIONED DRYING
TREND TO BEGIN SUNDAY AND CONTINUE THROUGH AT LEAST THE MIDDLE OF
NEXT WEEK. UPPER TROFFING IS FORECAST TO SET UP BOTH ALONG THE WEST
COAST AND INLAND OVER THE PAC NORTHWEST AND THIS WILL LEAD TO
STRENGTHENING SOUTHWEST FLOW ALOFT TO WORK INTO THE DESERT SOUTHWEST
AND GRADUALLY THIN OUT THE MOISTURE OVER SE CALIFORNIA AND THE LOWER
AZ DESERTS. BY NEXT MONDAY THUNDERSTORM CHANCES SHOULD BE CONFINED
PRIMARILY TO HIGHER TERRAIN AREAS EAST OF PHOENIX...ZONE 24 TO BE
EXACT. THERE WILL BE PERIODS OF HIGH CLOUDS MOVING THROUGH THE FLOW
BUT OVERALL DESERTS SHOULD RANGE FROM MOSTLY SUNNY TO PARTLY SUNNY
EACH DAY FROM MONDAY ONWARD. AS THE UPPER TROFFING DEVELOPS AND
HEIGHTS FALL...HIGH TEMPERATURES WILL STEADILY FALL OFF AND BY NEXT
MONDAY THE WARMER LOWER DESERTS WILL BE WELL UNDER 110. THE GREATER
PHOENIX AREA IS FORECAST TO DROP TO 105 ON MONDAY...AND EVENTUALLY
TO 103 ON WEDNESDAY AND THURSDAY. THE 103 DEGREE READINGS WILL EQUAL
THE CLIMATE NORMALS FOR THOSE DAYS.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND..
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

MOSTLY CLEAR SKIES AND LIGHT WINDS 10KT OR LESS EXPECTED AT ALL TAF
SITES. SKIES BECOME SCT-BKN AOA 10KFT ACROSS SOUTH-CENTRAL AZ...AND
THUNDERSTORM ACTIVITY WILL PICK UP AFTER 18Z OVER THE MOUNTAINS AND
HIGHER TERRAIN WELL EAST/NORTH OF PHOENIX...WITH SKIES REMAINING
MOSTLY CLEAR ACROSS SOUTHEAST CALIFORNIA. POSSIBLE FOR AN ISOLATED
STORM TO FORM OVER THE LOWER CENTRAL DESERTS AND GUSTY OUTFLOWS TO
IMPACT KPHX/KIWA/KSDL LATER THIS AFTERNOON AND EVENING.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...DRIER AND WARMER WEATHER WILL SPREAD INTO
REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...CB
AVIATION...MEYERS
FIRE WEATHER...VASQUEZ





000
FXUS65 KPSR 281233 AAA
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
530 AM MST FRI AUG 28 2015

.UPDATE...UPDATED AVIATION DISCUSSION.

&&

.SYNOPSIS... STRONG HIGH PRESSURE ALOFT WILL KEEP HIGH TEMPERATURES
WELL ABOVE SEASONAL NORMALS THROUGH SATURDAY WITH HOTTER LOWER
DESERTS REACHING OR EXCEEDING 110. THERE WILL BE SUFFICIENT MOISTURE
EAST OF THE LOWER COLORADO RIVER TO SUPPORT ISOLATED TO SCATTERED
AFTERNOON AND EVENING THUNDERSTORMS THROUGH SATURDAY. STARTING
SUNDAY A DRIER SOUTHWEST FLOW ALOFT WILL PUSH THE MOISTURE OFF TO
THE EAST AND BY MONDAY STORM CHANCES SHOULD BE CONFINED PRIMARILY TO
HIGHER TERRAIN AREAS TO THE EAST OF PHOENIX. THERE WILL BE A GRADUAL
COOLING TREND STARTING SUNDAY WITH CENTRAL DESERTS HIGH TEMPERATURES
DROPPING TO AROUND SEASONAL NORMALS BY THE MIDDLE OF NEXT WEEK.

&&

.DISCUSSION... STRONG HIGH PRESSURE ALOFT REMAINS SITUATED ACROSS
THE DESERT SOUTHWEST THIS MORNING...WITH H5 HEIGHTS AROUND 594DM
ACROSS THE SOUTHERN DESERTS. THIS LED TO HOT TEMPERATURES OVER THE
DESERTS YESTERDAY WITH HIGHS REACHING 110 OVER THE HOTTER LOWER
DESERTS. DESPITE SOMEWHAT WEAK FLOW ALOFT...MOISTURE AND INSTABILITY
WERE SUFFICIENT YESTERDAY TO ALLOW FOR SCATTERED STRONG STORMS TO
DEVELOP ACROSS MUCH OF SOUTH CENTRAL ARIZONA. OUTFLOW BOUNDARY
INTERACTIONS WERE THE MAIN FORCING FEATURE FOR THE STRONG
STORMS...NOT THE PRESENCE OF A SIGNIFICANT INVERTED TROF/SHORT WAVE
MOVING THROUGH THE FLOW. YESTERDAYS CONVECTION ENDED LONG AGO AND AT
2 AM IR IMAGERY SHOWED GENERALLY CLEAR SKIES FROM PHOENIX WESTWARD.
SURFACE DEW POINTS WERE ELEVATED AND WERE MOSTLY IN THE 60S WITH SOME
LOW 70S REPORTED.

THE TREND OF DRYING FROM THE WEST WILL BE PUT ON HOLD FOR THE NEXT
COUPLE OF DAYS OR SO...AND WE WILL BE LOOKING AT 2 MORE DAYS OF LOW
TO MODERATE GRADE MONSOON ACTIVITY ACROSS AREAS EAST OF THE LOWER
COLORADO RIVER. THE STRONG UPPER HIGH HAS BUILT WESTWARD A BIT AND
THE SOUTHWEST STEERING FLOW WILL BECOME MORE WEAK AND NONDESCRIPT
THROUGH SATURDAY...AS ARIZONA SITS UNDER THE CENTER OF THE STRONG
RIDGE. WITH MOISTURE REMAINING ELEVATED...PWAT VALUES ABOVE 1.5
INCHES IN MANY PLACES...PLENTY OF MLCAPE AVAILABLE...AND HIGH TEMPS
CLIMBING NEAR OF ABOVE 110 OVER THE HOTTER DESERTS...CONDITIONS ARE
SUITABLE FOR ISOLATED TO SCATTERED AFTERNOON AND EVENING STORMS
DEVELOPING TODAY AND SATURDAY. ONCE AGAIN...IT APPEARS THAT OUTFLOW
BOUNDARY INTERACTION WILL PLAY THE DOMINANT ROLE IN FORCING
CONVECTION AS MODELS DO NOT FORECAST ANY SIGNIFICANT
DISTURBANCES/INVERTED TROFS TO MOVE ACROSS THE AREA OVER THE NEXT 2
DAYS. POPS HAVE BEEN RAISED A BIT TODAY AND SATURDAY WILL STAY IN
THE SLIGHT CHANCE CATEGORY EAST OF THE LOWER CO RIVER...WITH CHANCE
VALUES OVER THE HIGHER TERRAIN EAST OF PHOENIX.

LATEST GFS AND ECMWF DETERMINISTIC GUIDANCE AS WELL AS ENSEMBLE
GUIDANCE REMAINS CONSISTENT IN CALLING FOR THE AFOREMENTIONED DRYING
TREND TO BEGIN SUNDAY AND CONTINUE THROUGH AT LEAST THE MIDDLE OF
NEXT WEEK. UPPER TROFFING IS FORECAST TO SET UP BOTH ALONG THE WEST
COAST AND INLAND OVER THE PAC NORTHWEST AND THIS WILL LEAD TO
STRENGTHENING SOUTHWEST FLOW ALOFT TO WORK INTO THE DESERT SOUTHWEST
AND GRADUALLY THIN OUT THE MOISTURE OVER SE CALIFORNIA AND THE LOWER
AZ DESERTS. BY NEXT MONDAY THUNDERSTORM CHANCES SHOULD BE CONFINED
PRIMARILY TO HIGHER TERRAIN AREAS EAST OF PHOENIX...ZONE 24 TO BE
EXACT. THERE WILL BE PERIODS OF HIGH CLOUDS MOVING THROUGH THE FLOW
BUT OVERALL DESERTS SHOULD RANGE FROM MOSTLY SUNNY TO PARTLY SUNNY
EACH DAY FROM MONDAY ONWARD. AS THE UPPER TROFFING DEVELOPS AND
HEIGHTS FALL...HIGH TEMPERATURES WILL STEADILY FALL OFF AND BY NEXT
MONDAY THE WARMER LOWER DESERTS WILL BE WELL UNDER 110. THE GREATER
PHOENIX AREA IS FORECAST TO DROP TO 105 ON MONDAY...AND EVENTUALLY
TO 103 ON WEDNESDAY AND THURSDAY. THE 103 DEGREE READINGS WILL EQUAL
THE CLIMATE NORMALS FOR THOSE DAYS.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND..
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

MOSTLY CLEAR SKIES AND LIGHT WINDS 10KT OR LESS EXPECTED AT ALL TAF
SITES. SKIES BECOME SCT-BKN AOA 10KFT ACROSS SOUTH-CENTRAL AZ...AND
THUNDERSTORM ACTIVITY WILL PICK UP AFTER 18Z OVER THE MOUNTAINS AND
HIGHER TERRAIN WELL EAST/NORTH OF PHOENIX...WITH SKIES REMAINING
MOSTLY CLEAR ACROSS SOUTHEAST CALIFORNIA. POSSIBLE FOR AN ISOLATED
STORM TO FORM OVER THE LOWER CENTRAL DESERTS AND GUSTY OUTFLOWS TO
IMPACT KPHX/KIWA/KSDL LATER THIS AFTERNOON AND EVENING.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...DRIER AND WARMER WEATHER WILL SPREAD INTO
REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...CB
AVIATION...MEYERS
FIRE WEATHER...VASQUEZ




000
FXUS65 KPSR 281010
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
310 AM MST FRI AUG 28 2015

.SYNOPSIS... STRONG HIGH PRESSURE ALOFT WILL KEEP HIGH TEMPERATURES
WELL ABOVE SEASONAL NORMALS THROUGH SATURDAY WITH HOTTER LOWER
DESERTS REACHING OR EXCEEDING 110. THERE WILL BE SUFFICIENT MOISTURE
EAST OF THE LOWER COLORADO RIVER TO SUPPORT ISOLATED TO SCATTERED
AFTERNOON AND EVENING THUNDERSTORMS THROUGH SATURDAY. STARTING
SUNDAY A DRIER SOUTHWEST FLOW ALOFT WILL PUSH THE MOISTURE OFF TO
THE EAST AND BY MONDAY STORM CHANCES SHOULD BE CONFINED PRIMARILY TO
HIGHER TERRAIN AREAS TO THE EAST OF PHOENIX. THERE WILL BE A GRADUAL
COOLING TREND STARTING SUNDAY WITH CENTRAL DESERTS HIGH TEMPERATURES
DROPPING TO AROUND SEASONAL NORMALS BY THE MIDDLE OF NEXT WEEK.

&&

.DISCUSSION... STRONG HIGH PRESSURE ALOFT REMAINS SITUATED ACROSS
THE DESERT SOUTHWEST THIS MORNING...WITH H5 HEIGHTS AROUND 594DM
ACROSS THE SOUTHERN DESERTS. THIS LED TO HOT TEMPERATURES OVER THE
DESERTS YESTERDAY WITH HIGHS REACHING 110 OVER THE HOTTER LOWER
DESERTS. DESPITE SOMEWHAT WEAK FLOW ALOFT...MOISTURE AND INSTABILITY
WERE SUFFICIENT YESTERDAY TO ALLOW FOR SCATTERED STRONG STORMS TO
DEVELOP ACROSS MUCH OF SOUTH CENTRAL ARIZONA. OUTFLOW BOUNDARY
INTERACTIONS WERE THE MAIN FORCING FEATURE FOR THE STRONG
STORMS...NOT THE PRESENCE OF A SIGNIFICANT INVERTED TROF/SHORT WAVE
MOVING THROUGH THE FLOW. YESTERDAYS CONVECTION ENDED LONG AGO AND AT
2 AM IR IMAGERY SHOWED GENERALLY CLEAR SKIES FROM PHOENIX WESTWARD.
SURFACE DEWPOINTS WERE ELEVATED AND WERE MOSTLY IN THE 60S WITH SOME
LOW 70S REPORTED.

THE TREND OF DRYING FROM THE WEST WILL BE PUT ON HOLD FOR THE NEXT
COUPLE OF DAYS OR SO...AND WE WILL BE LOOKING AT 2 MORE DAYS OF LOW
TO MODERATE GRADE MONSOON ACTIVITY ACROSS AREAS EAST OF THE LOWER
COLORADO RIVER. THE STRONG UPPER HIGH HAS BUILT WESTWARD A BIT AND
THE SOUTHWEST STEERING FLOW WILL BECOME MORE WEAK AND NONDESCRIPT
THROUGH SATURDAY...AS ARIZONA SITS UNDER THE CENTER OF THE STRONG
RIDGE. WITH MOISTURE REMAINING ELEVATED...PWAT VALUES ABOVE 1.5
INCHES IN MANY PLACES...PLENTY OF MLCAPE AVAILABLE...AND HIGH TEMPS
CLIMBING NEAR OF ABOVE 110 OVER THE HOTTER DESERTS...CONDITIONS ARE
SUITABLE FOR ISOLATED TO SCATTERED AFTERNOON AND EVENING STORMS
DEVELOPING TODAY AND SATURDAY. ONCE AGAIN...IT APPEARS THAT OUTFLOW
BOUNDARY INTERACTION WILL PLAY THE DOMINANT ROLE IN FORCING
CONVECTION AS MODELS DO NOT FORECAST ANY SIGNIFICANT
DISTURBANCES/INVERTED TROFS TO MOVE ACROSS THE AREA OVER THE NEXT 2
DAYS. POPS HAVE BEEN RAISED A BIT TODAY AND SATURDAY WILL STAY IN
THE SLIGHT CHANCE CATEGORY EAST OF THE LOWER CO RIVER...WITH CHANCE
VALUES OVER THE HIGHER TERRAIN EAST OF PHOENIX.

LATEST GFS AND ECMWF DETERMINISTIC GUIDANCE AS WELL AS ENSEMBLE
GUIDANCE REMAINS CONSISTENT IN CALLING FOR THE AFOREMENTIONED DRYING
TREND TO BEGIN SUNDAY AND CONTINUE THROUGH AT LEAST THE MIDDLE OF
NEXT WEEK. UPPER TROFFING IS FORECAST TO SET UP BOTH ALONG THE WEST
COAST AND INLAND OVER THE PAC NORTHWEST AND THIS WILL LEAD TO
STRENGTHENING SOUTHWEST FLOW ALOFT TO WORK INTO THE DESERT SOUTHWEST
AND GRADUALLY THIN OUT THE MOISTURE OVER SE CALIFORNIA AND THE LOWER
AZ DESERTS. BY NEXT MONDAY THUNDERSTORM CHANCES SHOULD BE CONFINED
PRIMARILY TO HIGHER TERRAIN AREAS EAST OF PHOENIX...ZONE 24 TO BE
EXACT. THERE WILL BE PERIODS OF HIGH CLOUDS MOVING THROUGH THE FLOW
BUT OVERALL DESERTS SHOULD RANGE FROM MOSTLY SUNNY TO PARTLY SUNNY
EACH DAY FROM MONDAY ONWARD. AS THE UPPER TROFFING DEVELOPS AND
HEIGHTS FALL...HIGH TEMPERATURES WILL STEADILY FALL OFF AND BY NEXT
MONDAY THE WARMER LOWER DESERTS WILL BE WELL UNDER 110. THE GREATER
PHOENIX AREA IS FORECAST TO DROP TO 105 ON MONDAY...AND EVENTUALLY
TO 103 ON WEDNESDAY AND THURSDAY. THE 103 DEGREE READINGS WILL EQUAL
THE CLIMATE NORMALS FOR THOSE DAYS.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND

CURRENT BKN CIGS TO PREVAIL THROUGH FRIDAY MORNING...THEN BECOME
MAINLY SCT BY FRIDAY AFTERNOON AS SLIGHTLY DRIER AIR WORKS ITS WAY
IN FROM THE WEST...WITH CLOUD BASES IN THE 8-10K FT RANGE RISING
INTO THE 10-12K FT RANGE ON FRIDAY. SOUTHEASTERLY WINDS TONIGHT AND
EARLY FRIDAY TO BECOME WESTERLY BY FRIDAY AFTERNOON. THUNDERSTORM
ACTIVITY TO REMAIN MAINLY WELL TO THE EAST OF THE TERMINALS ON
FRIDAY.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

FEW-SCT MID-LEVEL CIGS TO BECOME MAINLY CLR BY FRIDAY AFTERNOON.
WINDS TO REMAIN ON THE LIGHT SIDE...AOB 8KTS...MAINLY FOLLOWING
TYPICAL DIURNAL TRENDS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...

SUNDAY THROUGH THURSDAY...DRIER AND WARMER WEATHER WILL SPREAD INTO
REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...CB
AVIATION...PERCHA
FIRE WEATHER...VASQUEZ




000
FXUS65 KPSR 280530 AAA
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
1030 PM MST THU AUG 27 2015

.UPDATE...AVIATION DISCUSSION.

&&

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD THROUGH FRIDAY.
THE DRIER AIR WILL PUSH FURTHER EAST THIS WEEKEND...CONFINING RAIN
CHANCES TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH
THE WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION... A RATHER ACTIVE LATE AFTERNOON/EARLY EVENING ACROSS
SOUTH-CENTRAL ARIZONA...AND TO A LESSER EXTENT ACROSS SOUTHWEST
ARIZONA. IN SPITE OF WESTERLY FLOW ALOFT...WHICH IS NORMALLY
UNFAVORABLE FOR MONSOON STORMS TO MOVE INTO THE LOWER DESERTS...THE
COMBINATION OF AMPLE MOISTURE (PWATS AOA 1.50 INCH) AND A WEAK
SHORTWAVE MOVING ACROSS ARIZONA HELPED TO TRIGGER SCATTERED
SHOWERS AND THUNDERSTORMS ACROSS THE REGION. THE STRONGEST STORMS
AFFECTED THE WEST VALLEY AND TEMPE...WHERE SEVERE STORMS PRODUCED
DAMAGING WINDS AND LOCALIZED FLOODING THIS AFTERNOON. THINGS ARE
MUCH QUIETER AT THIS HOUR...WITH THUNDERSTORMS ACTIVITY NOW BEING
CONFINED TO EXTREME SE AZ AND OVER PARTS OF NW AZ. AS FAR AS THE
FORECAST IS CONCERNED FOR THE REST OF TONIGHT...THERE IS JUST A
SLIGHT CHANCE OF AN ISOLATED STORM OVER THE LOWER DESERTS THROUGH
THE REST OF THIS EVENING. TOMORROW LOOKS TO BE MUCH QUIETER...DUE TO
WEAK SHORTWAVE RIDGING/SUBSIDENCE MOVING INTO THE REGION FROM THE
WEST AND A REDUCTION OF AVAILABLE MOISTURE (MIXING RATIOS FALLING
AOB 8 G/KG AT MOST LOCATIONS BY THURSDAY AFTERNOON).

&&

.PREVIOUS DISCUSSION... WITHIN JUST THE LAST TWO HOURS...FROM 1830Z
THROUGH 2030Z...CONVECTIVE ACTIVITY ACROSS NORTH-CENTRAL AND WESTERN
ARIZONA HAS POPULATED AND FILLED IN QUITE NICELY. KEEPING A CLOSE
WATCH ON A SUITE OF HIGH-RESOLUTION MODEL FORECASTS THIS
MORNING...ALL HINTED AT AFTERNOON CONVECTION FROM YAVAPAI COUNTY
STRETCHING SOUTHEAST THROUGH MARICOPA COUNTY INCLUDING PHOENIX AND
INTO SOUTHERN GILA COUNTY FOR THE REMAINDER OF THIS AFTERNOON.
TIMING WAS A BIT OFF WITH THE MODELS COMPARED TO WHAT WAS ACTUALLY
OCCURRING...AND WITH CLEAR SKIES THIS MORNING THE TEMPERATURES
CLIMBED A BIT FASTER THAN ANTICIPATED SO CONVECTIVE POTENTIAL WAS
REALIZED RATHER RAPIDLY. WITH A SHORT WAVE MOVING THROUGH CENTRAL
ARIZONA...THE HIGH RES MODELS PICKED UP ON THAT AND HAVE BEEN VERY
CONSISTENT. PER THE 12Z SOUNDING FOR PSR...A
-8C TEMPERATURE AT 500MB PAIRED WITH OVER 1.6 INCH OF PRECIPITABLE
WATER PROVIDES A GOOD ENVIRONMENT FOR HEAVY RAIN PRODUCING
THUNDERSTORMS. SOME DIFFLUENCE FROM 500-300MB ACROSS CENTRAL ARIZONA
WILL PROVIDE A GOOD BOUNDARY FOR THUNDERSTORM ACTIVITY. WHILE STILL
UNDER A WESTERLY FLOW ALOFT...STEERING FLOW IS RATHER WEAK.

AS THE UPPER LEVEL HIGH BETTER PLACES ITSELF SOUTH OF THE BORDER AND
SLIGHTLY MORE WEST...TOMORROW BOASTS ANOTHER CHANCE FOR HIGH TERRAIN
CONVECTION. ANOTHER DISTURBANCE IN THE FLOW FROM 500MB TO 300MB AND
MINIMAL DRYING IN THE MID LEVELS MAY PROVIDE JUST ENOUGH OF TRIGGER
FOR SOME CONVECTIVE ACTIVITY FRIDAY AFTERNOON. THROUGH TUESDAY OF
NEXT WEEK...AN APPROACHING TROUGH FROM THE WEST WILL SUPPORT
CONTINUED SOUTHWESTERLY FLOW ALOFT AND MID-LEVEL MIXING RATIO VALUES
ARE FORECAST TO DIP BELOW 8 G/KG. A SUBTLE DRYING TREND AND
AN UNFAVORABLE MONSOON PATTERN LOOKS TO SETTLE IN THROUGH MID-WEEK
NEXT WEEK. TEMPERATURES WILL TREND UPWARD THROUGH THE WEEKEND AND
THEN HOLD ON TO PERSISTENCE NEAR SEASONAL AVERAGE THROUGH THE WEEK
AHEAD.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND

CURRENT BKN CIGS TO PREVAIL THROUGH FRIDAY MORNING...THEN BECOME
MAINLY SCT BY FRIDAY AFTERNOON AS SLIGHTLY DRIER AIR WORKS ITS WAY
IN FROM THE WEST...WITH CLOUD BASES IN THE 8-10K FT RANGE RISING
INTO THE 10-12K FT RANGE ON FRIDAY. SOUTHEASTERLY WINDS TONIGHT AND
EARLY FRIDAY TO BECOME WESTERLY BY FRIDAY AFTERNOON. THUNDERSTORM
ACTIVITY TO REMAIN MAINLY WELL TO THE EAST OF THE TERMINALS ON
FRIDAY.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

FEW-SCT MID-LEVEL CIGS TO BECOME MAINLY CLR BY FRIDAY AFTERNOON.
WINDS TO REMAIN ON THE LIGHT SIDE...AOB 8KTS...MAINLY FOLLOWING
TYPICAL DIURNAL TRENDS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...

SUNDAY THROUGH THURSDAY...DRIER AND WARMER WEATHER WILL SPREAD INTO
REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...PERCHA
AVIATION...PERCHA
FIRE WEATHER...VASQUEZ




000
FXUS65 KPSR 280530 AAA
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
1030 PM MST THU AUG 27 2015

.UPDATE...AVIATION DISCUSSION.

&&

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD THROUGH FRIDAY.
THE DRIER AIR WILL PUSH FURTHER EAST THIS WEEKEND...CONFINING RAIN
CHANCES TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH
THE WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION... A RATHER ACTIVE LATE AFTERNOON/EARLY EVENING ACROSS
SOUTH-CENTRAL ARIZONA...AND TO A LESSER EXTENT ACROSS SOUTHWEST
ARIZONA. IN SPITE OF WESTERLY FLOW ALOFT...WHICH IS NORMALLY
UNFAVORABLE FOR MONSOON STORMS TO MOVE INTO THE LOWER DESERTS...THE
COMBINATION OF AMPLE MOISTURE (PWATS AOA 1.50 INCH) AND A WEAK
SHORTWAVE MOVING ACROSS ARIZONA HELPED TO TRIGGER SCATTERED
SHOWERS AND THUNDERSTORMS ACROSS THE REGION. THE STRONGEST STORMS
AFFECTED THE WEST VALLEY AND TEMPE...WHERE SEVERE STORMS PRODUCED
DAMAGING WINDS AND LOCALIZED FLOODING THIS AFTERNOON. THINGS ARE
MUCH QUIETER AT THIS HOUR...WITH THUNDERSTORMS ACTIVITY NOW BEING
CONFINED TO EXTREME SE AZ AND OVER PARTS OF NW AZ. AS FAR AS THE
FORECAST IS CONCERNED FOR THE REST OF TONIGHT...THERE IS JUST A
SLIGHT CHANCE OF AN ISOLATED STORM OVER THE LOWER DESERTS THROUGH
THE REST OF THIS EVENING. TOMORROW LOOKS TO BE MUCH QUIETER...DUE TO
WEAK SHORTWAVE RIDGING/SUBSIDENCE MOVING INTO THE REGION FROM THE
WEST AND A REDUCTION OF AVAILABLE MOISTURE (MIXING RATIOS FALLING
AOB 8 G/KG AT MOST LOCATIONS BY THURSDAY AFTERNOON).

&&

.PREVIOUS DISCUSSION... WITHIN JUST THE LAST TWO HOURS...FROM 1830Z
THROUGH 2030Z...CONVECTIVE ACTIVITY ACROSS NORTH-CENTRAL AND WESTERN
ARIZONA HAS POPULATED AND FILLED IN QUITE NICELY. KEEPING A CLOSE
WATCH ON A SUITE OF HIGH-RESOLUTION MODEL FORECASTS THIS
MORNING...ALL HINTED AT AFTERNOON CONVECTION FROM YAVAPAI COUNTY
STRETCHING SOUTHEAST THROUGH MARICOPA COUNTY INCLUDING PHOENIX AND
INTO SOUTHERN GILA COUNTY FOR THE REMAINDER OF THIS AFTERNOON.
TIMING WAS A BIT OFF WITH THE MODELS COMPARED TO WHAT WAS ACTUALLY
OCCURRING...AND WITH CLEAR SKIES THIS MORNING THE TEMPERATURES
CLIMBED A BIT FASTER THAN ANTICIPATED SO CONVECTIVE POTENTIAL WAS
REALIZED RATHER RAPIDLY. WITH A SHORT WAVE MOVING THROUGH CENTRAL
ARIZONA...THE HIGH RES MODELS PICKED UP ON THAT AND HAVE BEEN VERY
CONSISTENT. PER THE 12Z SOUNDING FOR PSR...A
-8C TEMPERATURE AT 500MB PAIRED WITH OVER 1.6 INCH OF PRECIPITABLE
WATER PROVIDES A GOOD ENVIRONMENT FOR HEAVY RAIN PRODUCING
THUNDERSTORMS. SOME DIFFLUENCE FROM 500-300MB ACROSS CENTRAL ARIZONA
WILL PROVIDE A GOOD BOUNDARY FOR THUNDERSTORM ACTIVITY. WHILE STILL
UNDER A WESTERLY FLOW ALOFT...STEERING FLOW IS RATHER WEAK.

AS THE UPPER LEVEL HIGH BETTER PLACES ITSELF SOUTH OF THE BORDER AND
SLIGHTLY MORE WEST...TOMORROW BOASTS ANOTHER CHANCE FOR HIGH TERRAIN
CONVECTION. ANOTHER DISTURBANCE IN THE FLOW FROM 500MB TO 300MB AND
MINIMAL DRYING IN THE MID LEVELS MAY PROVIDE JUST ENOUGH OF TRIGGER
FOR SOME CONVECTIVE ACTIVITY FRIDAY AFTERNOON. THROUGH TUESDAY OF
NEXT WEEK...AN APPROACHING TROUGH FROM THE WEST WILL SUPPORT
CONTINUED SOUTHWESTERLY FLOW ALOFT AND MID-LEVEL MIXING RATIO VALUES
ARE FORECAST TO DIP BELOW 8 G/KG. A SUBTLE DRYING TREND AND
AN UNFAVORABLE MONSOON PATTERN LOOKS TO SETTLE IN THROUGH MID-WEEK
NEXT WEEK. TEMPERATURES WILL TREND UPWARD THROUGH THE WEEKEND AND
THEN HOLD ON TO PERSISTENCE NEAR SEASONAL AVERAGE THROUGH THE WEEK
AHEAD.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND

CURRENT BKN CIGS TO PREVAIL THROUGH FRIDAY MORNING...THEN BECOME
MAINLY SCT BY FRIDAY AFTERNOON AS SLIGHTLY DRIER AIR WORKS ITS WAY
IN FROM THE WEST...WITH CLOUD BASES IN THE 8-10K FT RANGE RISING
INTO THE 10-12K FT RANGE ON FRIDAY. SOUTHEASTERLY WINDS TONIGHT AND
EARLY FRIDAY TO BECOME WESTERLY BY FRIDAY AFTERNOON. THUNDERSTORM
ACTIVITY TO REMAIN MAINLY WELL TO THE EAST OF THE TERMINALS ON
FRIDAY.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

FEW-SCT MID-LEVEL CIGS TO BECOME MAINLY CLR BY FRIDAY AFTERNOON.
WINDS TO REMAIN ON THE LIGHT SIDE...AOB 8KTS...MAINLY FOLLOWING
TYPICAL DIURNAL TRENDS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...

SUNDAY THROUGH THURSDAY...DRIER AND WARMER WEATHER WILL SPREAD INTO
REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...PERCHA
AVIATION...PERCHA
FIRE WEATHER...VASQUEZ





000
FXUS65 KPSR 280530 AAA
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
1030 PM MST THU AUG 27 2015

.UPDATE...AVIATION DISCUSSION.

&&

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD THROUGH FRIDAY.
THE DRIER AIR WILL PUSH FURTHER EAST THIS WEEKEND...CONFINING RAIN
CHANCES TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH
THE WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION... A RATHER ACTIVE LATE AFTERNOON/EARLY EVENING ACROSS
SOUTH-CENTRAL ARIZONA...AND TO A LESSER EXTENT ACROSS SOUTHWEST
ARIZONA. IN SPITE OF WESTERLY FLOW ALOFT...WHICH IS NORMALLY
UNFAVORABLE FOR MONSOON STORMS TO MOVE INTO THE LOWER DESERTS...THE
COMBINATION OF AMPLE MOISTURE (PWATS AOA 1.50 INCH) AND A WEAK
SHORTWAVE MOVING ACROSS ARIZONA HELPED TO TRIGGER SCATTERED
SHOWERS AND THUNDERSTORMS ACROSS THE REGION. THE STRONGEST STORMS
AFFECTED THE WEST VALLEY AND TEMPE...WHERE SEVERE STORMS PRODUCED
DAMAGING WINDS AND LOCALIZED FLOODING THIS AFTERNOON. THINGS ARE
MUCH QUIETER AT THIS HOUR...WITH THUNDERSTORMS ACTIVITY NOW BEING
CONFINED TO EXTREME SE AZ AND OVER PARTS OF NW AZ. AS FAR AS THE
FORECAST IS CONCERNED FOR THE REST OF TONIGHT...THERE IS JUST A
SLIGHT CHANCE OF AN ISOLATED STORM OVER THE LOWER DESERTS THROUGH
THE REST OF THIS EVENING. TOMORROW LOOKS TO BE MUCH QUIETER...DUE TO
WEAK SHORTWAVE RIDGING/SUBSIDENCE MOVING INTO THE REGION FROM THE
WEST AND A REDUCTION OF AVAILABLE MOISTURE (MIXING RATIOS FALLING
AOB 8 G/KG AT MOST LOCATIONS BY THURSDAY AFTERNOON).

&&

.PREVIOUS DISCUSSION... WITHIN JUST THE LAST TWO HOURS...FROM 1830Z
THROUGH 2030Z...CONVECTIVE ACTIVITY ACROSS NORTH-CENTRAL AND WESTERN
ARIZONA HAS POPULATED AND FILLED IN QUITE NICELY. KEEPING A CLOSE
WATCH ON A SUITE OF HIGH-RESOLUTION MODEL FORECASTS THIS
MORNING...ALL HINTED AT AFTERNOON CONVECTION FROM YAVAPAI COUNTY
STRETCHING SOUTHEAST THROUGH MARICOPA COUNTY INCLUDING PHOENIX AND
INTO SOUTHERN GILA COUNTY FOR THE REMAINDER OF THIS AFTERNOON.
TIMING WAS A BIT OFF WITH THE MODELS COMPARED TO WHAT WAS ACTUALLY
OCCURRING...AND WITH CLEAR SKIES THIS MORNING THE TEMPERATURES
CLIMBED A BIT FASTER THAN ANTICIPATED SO CONVECTIVE POTENTIAL WAS
REALIZED RATHER RAPIDLY. WITH A SHORT WAVE MOVING THROUGH CENTRAL
ARIZONA...THE HIGH RES MODELS PICKED UP ON THAT AND HAVE BEEN VERY
CONSISTENT. PER THE 12Z SOUNDING FOR PSR...A
-8C TEMPERATURE AT 500MB PAIRED WITH OVER 1.6 INCH OF PRECIPITABLE
WATER PROVIDES A GOOD ENVIRONMENT FOR HEAVY RAIN PRODUCING
THUNDERSTORMS. SOME DIFFLUENCE FROM 500-300MB ACROSS CENTRAL ARIZONA
WILL PROVIDE A GOOD BOUNDARY FOR THUNDERSTORM ACTIVITY. WHILE STILL
UNDER A WESTERLY FLOW ALOFT...STEERING FLOW IS RATHER WEAK.

AS THE UPPER LEVEL HIGH BETTER PLACES ITSELF SOUTH OF THE BORDER AND
SLIGHTLY MORE WEST...TOMORROW BOASTS ANOTHER CHANCE FOR HIGH TERRAIN
CONVECTION. ANOTHER DISTURBANCE IN THE FLOW FROM 500MB TO 300MB AND
MINIMAL DRYING IN THE MID LEVELS MAY PROVIDE JUST ENOUGH OF TRIGGER
FOR SOME CONVECTIVE ACTIVITY FRIDAY AFTERNOON. THROUGH TUESDAY OF
NEXT WEEK...AN APPROACHING TROUGH FROM THE WEST WILL SUPPORT
CONTINUED SOUTHWESTERLY FLOW ALOFT AND MID-LEVEL MIXING RATIO VALUES
ARE FORECAST TO DIP BELOW 8 G/KG. A SUBTLE DRYING TREND AND
AN UNFAVORABLE MONSOON PATTERN LOOKS TO SETTLE IN THROUGH MID-WEEK
NEXT WEEK. TEMPERATURES WILL TREND UPWARD THROUGH THE WEEKEND AND
THEN HOLD ON TO PERSISTENCE NEAR SEASONAL AVERAGE THROUGH THE WEEK
AHEAD.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND

CURRENT BKN CIGS TO PREVAIL THROUGH FRIDAY MORNING...THEN BECOME
MAINLY SCT BY FRIDAY AFTERNOON AS SLIGHTLY DRIER AIR WORKS ITS WAY
IN FROM THE WEST...WITH CLOUD BASES IN THE 8-10K FT RANGE RISING
INTO THE 10-12K FT RANGE ON FRIDAY. SOUTHEASTERLY WINDS TONIGHT AND
EARLY FRIDAY TO BECOME WESTERLY BY FRIDAY AFTERNOON. THUNDERSTORM
ACTIVITY TO REMAIN MAINLY WELL TO THE EAST OF THE TERMINALS ON
FRIDAY.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

FEW-SCT MID-LEVEL CIGS TO BECOME MAINLY CLR BY FRIDAY AFTERNOON.
WINDS TO REMAIN ON THE LIGHT SIDE...AOB 8KTS...MAINLY FOLLOWING
TYPICAL DIURNAL TRENDS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...

SUNDAY THROUGH THURSDAY...DRIER AND WARMER WEATHER WILL SPREAD INTO
REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...PERCHA
AVIATION...PERCHA
FIRE WEATHER...VASQUEZ





000
FXUS65 KPSR 280341
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
840 PM MST THU AUG 27 2015

&&

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD THROUGH FRIDAY.
THE DRIER AIR WILL PUSH FURTHER EAST THIS WEEKEND...CONFINING RAIN
CHANCES TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH
THE WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION... A RATHER ACTIVE LATE AFTERNOON/EARLY EVENING ACROSS
SOUTH-CENTRAL ARIZONA...AND TO A LESSER EXTENT ACROSS SOUTHWEST
ARIZONA. IN SPITE OF WESTERLY FLOW ALOFT...WHICH IS NORMALLY
UNFAVORABLE FOR MONSOON STORMS TO MOVE INTO THE LOWER DESERTS...THE
COMBINATION OF AMPLE MOISTURE (PWATS AOA 1.50 INCH) AND A WEAK
SHORTWAVE MOVING ACROSS ARIZONA HELPED TO TRIGGER SCATTERED
SHOWERS AND THUNDERSTORMS ACROSS THE REGION. THE STRONGEST STORMS
AFFECTED THE WEST VALLEY AND TEMPE...WHERE SEVERE STORMS PRODUCED
DAMAGING WINDS AND LOCALIZED FLOODING THIS AFTERNOON. THINGS ARE
MUCH QUIETER AT THIS HOUR...WITH THUNDERSTORMS ACTIVITY NOW BEING
CONFINED TO EXTREME SE AZ AND OVER PARTS OF NW AZ. AS FAR AS THE
FORECAST IS CONCERNED FOR THE REST OF TONIGHT...THERE IS JUST A
SLIGHT CHANCE OF AN ISOLATED STORM OVER THE LOWER DESERTS THROUGH
THE REST OF THIS EVENING. TOMORROW LOOKS TO BE MUCH QUIETER...DUE TO
WEAK SHORTWAVE RIDGING/SUBSIDENCE MOVING INTO THE REGION FROM THE
WEST AND A REDUCTION OF AVAILABLE MOISTURE (MIXING RATIOS FALLING
AOB 8 G/KG AT MOST LOCATIONS BY THURSDAY AFTERNOON).

&&

.PREVIOUS DISCUSSION... WITHIN JUST THE LAST TWO HOURS...FROM 1830Z
THROUGH 2030Z...CONVECTIVE ACTIVITY ACROSS NORTH-CENTRAL AND WESTERN
ARIZONA HAS POPULATED AND FILLED IN QUITE NICELY. KEEPING A CLOSE
WATCH ON A SUITE OF HIGH-RESOLUTION MODEL FORECASTS THIS
MORNING...ALL HINTED AT AFTERNOON CONVECTION FROM YAVAPAI COUNTY
STRETCHING SOUTHEAST THROUGH MARICOPA COUNTY INCLUDING PHOENIX AND
INTO SOUTHERN GILA COUNTY FOR THE REMAINDER OF THIS AFTERNOON.
TIMING WAS A BIT OFF WITH THE MODELS COMPARED TO WHAT WAS ACTUALLY
OCCURRING...AND WITH CLEAR SKIES THIS MORNING THE TEMPERATURES
CLIMBED A BIT FASTER THAN ANTICIPATED SO CONVECTIVE POTENTIAL WAS
REALIZED RATHER RAPIDLY. WITH A SHORT WAVE MOVING THROUGH CENTRAL
ARIZONA...THE HIGH RES MODELS PICKED UP ON THAT AND HAVE BEEN VERY
CONSISTENT. PER THE 12Z SOUNDING FOR PSR...A
-8C TEMPERATURE AT 500MB PAIRED WITH OVER 1.6 INCH OF PRECIPITABLE
WATER PROVIDES A GOOD ENVIRONMENT FOR HEAVY RAIN PRODUCING
THUNDERSTORMS. SOME DIFFLUENCE FROM 500-300MB ACROSS CENTRAL ARIZONA
WILL PROVIDE A GOOD BOUNDARY FOR THUNDERSTORM ACTIVITY. WHILE STILL
UNDER A WESTERLY FLOW ALOFT...STEERING FLOW IS RATHER WEAK.

AS THE UPPER LEVEL HIGH BETTER PLACES ITSELF SOUTH OF THE BORDER AND
SLIGHTLY MORE WEST...TOMORROW BOASTS ANOTHER CHANCE FOR HIGH TERRAIN
CONVECTION. ANOTHER DISTURBANCE IN THE FLOW FROM 500MB TO 300MB AND
MINIMAL DRYING IN THE MID LEVELS MAY PROVIDE JUST ENOUGH OF TRIGGER
FOR SOME CONVECTIVE ACTIVITY FRIDAY AFTERNOON. THROUGH TUESDAY OF
NEXT WEEK...AN APPROACHING TROUGH FROM THE WEST WILL SUPPORT
CONTINUED SOUTHWESTERLY FLOW ALOFT AND MID-LEVEL MIXING RATIO VALUES
ARE FORECAST TO DIP BELOW 8 G/KG. A SUBTLE DRYING TREND AND
AN UNFAVORABLE MONSOON PATTERN LOOKS TO SETTLE IN THROUGH MID-WEEK
NEXT WEEK. TEMPERATURES WILL TREND UPWARD THROUGH THE WEEKEND AND
THEN HOLD ON TO PERSISTENCE NEAR SEASONAL AVERAGE THROUGH THE WEEK
AHEAD.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND

THROUGH 04Z FRI...SCT-NMRS TSTMS OVER THE DISTANT MOUNTAINS NORTH OF
PHOENIX WILL LIKELY GENERATE A SOUTHWARD MOVING OUTFLOW BOUNDARY
ACROSS THE PHOENIX METRO AREA. SINCE MONSOON MOISTURE IS RELATIVELY
HIGH FOR TODAY...THE SOUTHWARD MOVING OUTFLOW BOUNDARY WILL LIKELY
TRIGGER TSTMS ALONG AND JUST BEHIND THE BOUNDARY AS IT MOVES SOUTH
THRU THE PHOENIX VALLEY. TSTMS WILL DVLP IN THE VICINITY OF VALLEY
AIRPORTS. THEREFORE THROUGH 04Z FRI...SCT-BKN CLDS BASED 8 TO 10
THSD AGL WITH A FEW TSTMS AND GUSTY ERRATIC WINDS. FROM 04Z FRI TO
06Z FRI...SCT-BKN CLDS 8-10 THSD AGL WITH ISOLATED SHWRS. FROM 06Z
FRI TO 16Z FRI...SCT CLDS BASED 8 TO 10 THSD AGL WITH BKN HIGH
CLOUDS.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
THROUGH 07Z FRI...SCT CLDS 8 TO 10 THSD AGL. SOUTH TO SOUTHWEST WIND
8 TO 10 KNOTS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...

SUNDAY THROUGH THURSDAY...DRIER AND WARMER WEATHER WILL SPREAD INTO
REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...PERCHA
AVIATION...VASQUEZ
FIRE WEATHER...VASQUEZ




000
FXUS65 KPSR 280341
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
840 PM MST THU AUG 27 2015

&&

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD THROUGH FRIDAY.
THE DRIER AIR WILL PUSH FURTHER EAST THIS WEEKEND...CONFINING RAIN
CHANCES TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH
THE WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION... A RATHER ACTIVE LATE AFTERNOON/EARLY EVENING ACROSS
SOUTH-CENTRAL ARIZONA...AND TO A LESSER EXTENT ACROSS SOUTHWEST
ARIZONA. IN SPITE OF WESTERLY FLOW ALOFT...WHICH IS NORMALLY
UNFAVORABLE FOR MONSOON STORMS TO MOVE INTO THE LOWER DESERTS...THE
COMBINATION OF AMPLE MOISTURE (PWATS AOA 1.50 INCH) AND A WEAK
SHORTWAVE MOVING ACROSS ARIZONA HELPED TO TRIGGER SCATTERED
SHOWERS AND THUNDERSTORMS ACROSS THE REGION. THE STRONGEST STORMS
AFFECTED THE WEST VALLEY AND TEMPE...WHERE SEVERE STORMS PRODUCED
DAMAGING WINDS AND LOCALIZED FLOODING THIS AFTERNOON. THINGS ARE
MUCH QUIETER AT THIS HOUR...WITH THUNDERSTORMS ACTIVITY NOW BEING
CONFINED TO EXTREME SE AZ AND OVER PARTS OF NW AZ. AS FAR AS THE
FORECAST IS CONCERNED FOR THE REST OF TONIGHT...THERE IS JUST A
SLIGHT CHANCE OF AN ISOLATED STORM OVER THE LOWER DESERTS THROUGH
THE REST OF THIS EVENING. TOMORROW LOOKS TO BE MUCH QUIETER...DUE TO
WEAK SHORTWAVE RIDGING/SUBSIDENCE MOVING INTO THE REGION FROM THE
WEST AND A REDUCTION OF AVAILABLE MOISTURE (MIXING RATIOS FALLING
AOB 8 G/KG AT MOST LOCATIONS BY THURSDAY AFTERNOON).

&&

.PREVIOUS DISCUSSION... WITHIN JUST THE LAST TWO HOURS...FROM 1830Z
THROUGH 2030Z...CONVECTIVE ACTIVITY ACROSS NORTH-CENTRAL AND WESTERN
ARIZONA HAS POPULATED AND FILLED IN QUITE NICELY. KEEPING A CLOSE
WATCH ON A SUITE OF HIGH-RESOLUTION MODEL FORECASTS THIS
MORNING...ALL HINTED AT AFTERNOON CONVECTION FROM YAVAPAI COUNTY
STRETCHING SOUTHEAST THROUGH MARICOPA COUNTY INCLUDING PHOENIX AND
INTO SOUTHERN GILA COUNTY FOR THE REMAINDER OF THIS AFTERNOON.
TIMING WAS A BIT OFF WITH THE MODELS COMPARED TO WHAT WAS ACTUALLY
OCCURRING...AND WITH CLEAR SKIES THIS MORNING THE TEMPERATURES
CLIMBED A BIT FASTER THAN ANTICIPATED SO CONVECTIVE POTENTIAL WAS
REALIZED RATHER RAPIDLY. WITH A SHORT WAVE MOVING THROUGH CENTRAL
ARIZONA...THE HIGH RES MODELS PICKED UP ON THAT AND HAVE BEEN VERY
CONSISTENT. PER THE 12Z SOUNDING FOR PSR...A
-8C TEMPERATURE AT 500MB PAIRED WITH OVER 1.6 INCH OF PRECIPITABLE
WATER PROVIDES A GOOD ENVIRONMENT FOR HEAVY RAIN PRODUCING
THUNDERSTORMS. SOME DIFFLUENCE FROM 500-300MB ACROSS CENTRAL ARIZONA
WILL PROVIDE A GOOD BOUNDARY FOR THUNDERSTORM ACTIVITY. WHILE STILL
UNDER A WESTERLY FLOW ALOFT...STEERING FLOW IS RATHER WEAK.

AS THE UPPER LEVEL HIGH BETTER PLACES ITSELF SOUTH OF THE BORDER AND
SLIGHTLY MORE WEST...TOMORROW BOASTS ANOTHER CHANCE FOR HIGH TERRAIN
CONVECTION. ANOTHER DISTURBANCE IN THE FLOW FROM 500MB TO 300MB AND
MINIMAL DRYING IN THE MID LEVELS MAY PROVIDE JUST ENOUGH OF TRIGGER
FOR SOME CONVECTIVE ACTIVITY FRIDAY AFTERNOON. THROUGH TUESDAY OF
NEXT WEEK...AN APPROACHING TROUGH FROM THE WEST WILL SUPPORT
CONTINUED SOUTHWESTERLY FLOW ALOFT AND MID-LEVEL MIXING RATIO VALUES
ARE FORECAST TO DIP BELOW 8 G/KG. A SUBTLE DRYING TREND AND
AN UNFAVORABLE MONSOON PATTERN LOOKS TO SETTLE IN THROUGH MID-WEEK
NEXT WEEK. TEMPERATURES WILL TREND UPWARD THROUGH THE WEEKEND AND
THEN HOLD ON TO PERSISTENCE NEAR SEASONAL AVERAGE THROUGH THE WEEK
AHEAD.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND

THROUGH 04Z FRI...SCT-NMRS TSTMS OVER THE DISTANT MOUNTAINS NORTH OF
PHOENIX WILL LIKELY GENERATE A SOUTHWARD MOVING OUTFLOW BOUNDARY
ACROSS THE PHOENIX METRO AREA. SINCE MONSOON MOISTURE IS RELATIVELY
HIGH FOR TODAY...THE SOUTHWARD MOVING OUTFLOW BOUNDARY WILL LIKELY
TRIGGER TSTMS ALONG AND JUST BEHIND THE BOUNDARY AS IT MOVES SOUTH
THRU THE PHOENIX VALLEY. TSTMS WILL DVLP IN THE VICINITY OF VALLEY
AIRPORTS. THEREFORE THROUGH 04Z FRI...SCT-BKN CLDS BASED 8 TO 10
THSD AGL WITH A FEW TSTMS AND GUSTY ERRATIC WINDS. FROM 04Z FRI TO
06Z FRI...SCT-BKN CLDS 8-10 THSD AGL WITH ISOLATED SHWRS. FROM 06Z
FRI TO 16Z FRI...SCT CLDS BASED 8 TO 10 THSD AGL WITH BKN HIGH
CLOUDS.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
THROUGH 07Z FRI...SCT CLDS 8 TO 10 THSD AGL. SOUTH TO SOUTHWEST WIND
8 TO 10 KNOTS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...

SUNDAY THROUGH THURSDAY...DRIER AND WARMER WEATHER WILL SPREAD INTO
REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...PERCHA
AVIATION...VASQUEZ
FIRE WEATHER...VASQUEZ





000
FXUS65 KPSR 272202
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
310 PM MST THU AUG 27 2015

.UPDATE...FIRE WEATHER DISCUSSION.

&&

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD THROUGH FRIDAY.
THE DRIER AIR WILL PUSH FURTHER EAST THIS WEEKEND...CONFINING RAIN
CHANCES TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH
THE WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION...
WITHIN JUST THE LAST TWO HOURS...FROM 1830Z THROUGH
2030Z...CONVECTIVE ACTIVITY ACROSS NORTH-CENTRAL AND WESTERN ARIZONA
HAS POPULATED AND FILLED IN QUITE NICELY. KEEPING A CLOSE WATCH ON A
SUITE OF HIGH-RESOLUTION MODEL FORECASTS THIS MORNING...ALL HINTED AT
AFTERNOON CONVECTION FROM YAVAPAI COUNTY STRETCHING SOUTHEAST THROUGH
MARICOPA COUNTY INCLUDING PHOENIX AND INTO SOUTHERN GILA COUNTY FOR
THE REMAINDER OF THIS AFTERNOON. TIMING WAS A BIT OFF WITH THE MODELS
COMPARED TO WHAT WAS ACTUALLY OCCURRING...AND WITH CLEAR SKIES THIS
MORNING THE TEMPERATURES CLIMBED A BIT FASTER THAN ANTICIPATED SO
CONVECTIVE POTENTIAL WAS REALIZED RATHER RAPIDLY. WITH A SHORT WAVE
MOVING THROUGH CENTRAL ARIZONA...THE HIGH RES MODELS PICKED UP ON
THAT AND HAVE BEEN VERY CONSISTENT. PER THE 12Z SOUNDING FOR PSR...A
-8C TEMPERATURE AT 500MB PAIRED WITH OVER 1.6 INCH OF PRECIPITABLE
WATER PROVIDES A GOOD ENVIRONMENT FOR HEAVY RAIN PRODUCING
THUNDERSTORMS. SOME DIFFLUENCE FROM 500-300MB ACROSS CENTRAL ARIZONA
WILL PROVIDE A GOOD BOUNDARY FOR THUNDERSTORM ACTIVITY. WHILE STILL
UNDER A WESTERLY FLOW ALOFT...STEERING FLOW IS RATHER WEAK.

AS THE UPPER LEVEL HIGH BETTER PLACES ITSELF SOUTH OF THE BORDER AND
SLIGHTLY MORE WEST...TOMORROW BOASTS ANOTHER CHANCE FOR HIGH TERRAIN
CONVECTION. ANOTHER DISTURBANCE IN THE FLOW FROM 500MB TO 300MB AND
MINIMAL DRYING IN THE MID LEVELS MAY PROVIDE JUST ENOUGH OF TRIGGER
FOR SOME CONVECTIVE ACTIVITY FRIDAY AFTERNOON. THROUGH TUESDAY OF
NEXT WEEK...AN APPROACHING TROUGH FROM THE WEST WILL SUPPORT
CONTINUED SOUTHWESTERLY FLOW ALOFT AND MID-LEVEL MIXING RATIO VALUES
ARE FORECAST TO DIP BELOW 8 G/KG. A SUBTLE DRYING TREND AND
AN UNFAVORABLE MONSOON PATTERN LOOKS TO SETTLE IN THROUGH MID-WEEK
NEXT WEEK. TEMPERATURES WILL TREND UPWARD THROUGH THE WEEKEND AND
THEN HOLD ON TO PERSISTENCE NEAR SEASONAL AVERAGE THROUGH THE WEEK
AHEAD.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND

THROUGH 04Z FRI...SCT-NMRS TSTMS OVER THE DISTANT MOUNTAINS NORTH OF
PHOENIX WILL LIKELY GENERATE A SOUTHWARD MOVING OUTFLOW BOUNDARY
ACROSS THE PHOENIX METRO AREA. SINCE MONSOON MOISTURE IS RELATIVELY
HIGH FOR TODAY...THE SOUTHWARD MOVING OUTFLOW BOUNDARY WILL LIKELY
TRIGGER TSTMS ALONG AND JUST BEHIND THE BOUNDARY AS IT MOVES SOUTH
THRU THE PHOENIX VALLEY. TSTMS WILL DVLP IN THE VICINITY OF VALLEY
AIRPORTS. THEREFORE THROUGH 04Z FRI...SCT-BKN CLDS BASED 8 TO 10
THSD AGL WITH A FEW TSTMS AND GUSTY ERRATIC WINDS. FROM 04Z FRI TO
06Z FRI...SCT-BKN CLDS 8-10 THSD AGL WITH ISOLATED SHWRS. FROM 06Z
FRI TO 16Z FRI...SCT CLDS BASED 8 TO 10 THSD AGL WITH BKN HIGH
CLOUDS.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
THROUGH 07Z FRI...SCT CLDS 8 TO 10 THSD AGL. SOUTH TO SOUTHWEST WIND
8 TO 10 KNOTS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...

SUNDAY THROUGH THURSDAY...DRIER AND WARMER WEATHER WILL SPREAD INTO
REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...DEWEY
AVIATION...VASQUEZ
FIRE WEATHER...VASQUEZ




000
FXUS65 KPSR 272153
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
253 PM MST THU AUG 27 2015

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD THROUGH FRIDAY.
THE DRIER AIR WILL PUSH FURTHER EAST THIS WEEKEND...CONFINING RAIN
CHANCES TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH
THE WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION...
WITHIN JUST THE LAST TWO HOURS...FROM 1830Z THROUGH
2030Z...CONVECTIVE ACTIVITY ACROSS NORTH-CENTRAL AND WESTERN ARIZONA
HAS POPULATED AND FILLED IN QUITE NICELY. KEEPING A CLOSE WATCH ON A
SUITE OF HIGH-RESOLUTION MODEL FORECASTS THIS MORNING...ALL HINTED AT
AFTERNOON CONVECTION FROM YAVAPAI COUNTY STRETCHING SOUTHEAST THROUGH
MARICOPA COUNTY INCLUDING PHOENIX AND INTO SOUTHERN GILA COUNTY FOR
THE REMAINDER OF THIS AFTERNOON. TIMING WAS A BIT OFF WITH THE MODELS
COMPARED TO WHAT WAS ACTUALLY OCCURRING...AND WITH CLEAR SKIES THIS
MORNING THE TEMPERATURES CLIMBED A BIT FASTER THAN ANTICIPATED SO
CONVECTIVE POTENTIAL WAS REALIZED RATHER RAPIDLY. WITH A SHORT WAVE
MOVING THROUGH CENTRAL ARIZONA...THE HIGH RES MODELS PICKED UP ON
THAT AND HAVE BEEN VERY CONSISTENT. PER THE 12Z SOUNDING FOR PSR...A
-8C TEMPERATURE AT 500MB PAIRED WITH OVER 1.6 INCH OF PRECIPITABLE
WATER PROVIDES A GOOD ENVIRONMENT FOR HEAVY RAIN PRODUCING
THUNDERSTORMS. SOME DIFFLUENCE FROM 500-300MB ACROSS CENTRAL ARIZONA
WILL PROVIDE A GOOD BOUNDARY FOR THUNDERSTORM ACTIVITY. WHILE STILL
UNDER A WESTERLY FLOW ALOFT...STEERING FLOW IS RATHER WEAK.

AS THE UPPER LEVEL HIGH BETTER PLACES ITSELF SOUTH OF THE BORDER AND
SLIGHTLY MORE WEST...TOMORROW BOASTS ANOTHER CHANCE FOR HIGH TERRAIN
CONVECTION. ANOTHER DISTURBANCE IN THE FLOW FROM 500MB TO 300MB AND
MINIMAL DRYING IN THE MID LEVELS MAY PROVIDE JUST ENOUGH OF TRIGGER
FOR SOME CONVECTIVE ACTIVITY FRIDAY AFTERNOON. THROUGH TUESDAY OF
NEXT WEEK...AN APPROACHING TROUGH FROM THE WEST WILL SUPPORT
CONTINUED SOUTHWESTERLY FLOW ALOFT AND MID-LEVEL MIXING RATIO VALUES
ARE FORECAST TO DIP BELOW 8 G/KG. A SUBTLE DRYING TREND AND
AN UNFAVORABLE MONSOON PATTERN LOOKS TO SETTLE IN THROUGH MID-WEEK
NEXT WEEK. TEMPERATURES WILL TREND UPWARD THROUGH THE WEEKEND AND
THEN HOLD ON TO PERSISTENCE NEAR SEASONAL AVERAGE THROUGH THE WEEK
AHEAD.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND

THROUGH 04Z FRI...SCT-NMRS TSTMS OVER THE DISTANT MOUNTAINS NORTH OF
PHOENIX WILL LIKELY GENERATE A SOUTHWARD MOVING OUTFLOW BOUNDARY
ACROSS THE PHOENIX METRO AREA. SINCE MONSOON MOISTURE IS RELATIVELY
HIGH FOR TODAY...THE SOUTHWARD MOVING OUTFLOW BOUNDARY WILL LIKELY
TRIGGER TSTMS ALONG AND JUST BEHIND THE BOUNDARY AS IT MOVES SOUTH
THRU THE PHOENIX VALLEY. TSTMS WILL DVLP IN THE VICINITY OF VALLEY
AIRPORTS. THEREFORE THROUGH 04Z FRI...SCT-BKN CLDS BASED 8 TO 10
THSD AGL WITH A FEW TSTMS AND GUSTY ERRATIC WINDS. FROM 04Z FRI TO
06Z FRI...SCT-BKN CLDS 8-10 THSD AGL WITH ISOLATED SHWRS. FROM 06Z
FRI TO 16Z FRI...SCT CLDS BASED 8 TO 10 THSD AGL WITH BKN HIGH
CLOUDS.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
THROUGH 07Z FRI...SCT CLDS 8 TO 10 THSD AGL. SOUTH TO SOUTHWEST WIND
8 TO 10 KNOTS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...

SATURDAY THROUGH WEDNESDAY...DRIER AND WARMER WEATHER WILL SPREAD
INTO REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...DEWEY
AVIATION...VASQUEZ
FIRE WEATHER...VASQUEZ/CB




000
FXUS65 KPSR 272153
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
253 PM MST THU AUG 27 2015

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD THROUGH FRIDAY.
THE DRIER AIR WILL PUSH FURTHER EAST THIS WEEKEND...CONFINING RAIN
CHANCES TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH
THE WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION...
WITHIN JUST THE LAST TWO HOURS...FROM 1830Z THROUGH
2030Z...CONVECTIVE ACTIVITY ACROSS NORTH-CENTRAL AND WESTERN ARIZONA
HAS POPULATED AND FILLED IN QUITE NICELY. KEEPING A CLOSE WATCH ON A
SUITE OF HIGH-RESOLUTION MODEL FORECASTS THIS MORNING...ALL HINTED AT
AFTERNOON CONVECTION FROM YAVAPAI COUNTY STRETCHING SOUTHEAST THROUGH
MARICOPA COUNTY INCLUDING PHOENIX AND INTO SOUTHERN GILA COUNTY FOR
THE REMAINDER OF THIS AFTERNOON. TIMING WAS A BIT OFF WITH THE MODELS
COMPARED TO WHAT WAS ACTUALLY OCCURRING...AND WITH CLEAR SKIES THIS
MORNING THE TEMPERATURES CLIMBED A BIT FASTER THAN ANTICIPATED SO
CONVECTIVE POTENTIAL WAS REALIZED RATHER RAPIDLY. WITH A SHORT WAVE
MOVING THROUGH CENTRAL ARIZONA...THE HIGH RES MODELS PICKED UP ON
THAT AND HAVE BEEN VERY CONSISTENT. PER THE 12Z SOUNDING FOR PSR...A
-8C TEMPERATURE AT 500MB PAIRED WITH OVER 1.6 INCH OF PRECIPITABLE
WATER PROVIDES A GOOD ENVIRONMENT FOR HEAVY RAIN PRODUCING
THUNDERSTORMS. SOME DIFFLUENCE FROM 500-300MB ACROSS CENTRAL ARIZONA
WILL PROVIDE A GOOD BOUNDARY FOR THUNDERSTORM ACTIVITY. WHILE STILL
UNDER A WESTERLY FLOW ALOFT...STEERING FLOW IS RATHER WEAK.

AS THE UPPER LEVEL HIGH BETTER PLACES ITSELF SOUTH OF THE BORDER AND
SLIGHTLY MORE WEST...TOMORROW BOASTS ANOTHER CHANCE FOR HIGH TERRAIN
CONVECTION. ANOTHER DISTURBANCE IN THE FLOW FROM 500MB TO 300MB AND
MINIMAL DRYING IN THE MID LEVELS MAY PROVIDE JUST ENOUGH OF TRIGGER
FOR SOME CONVECTIVE ACTIVITY FRIDAY AFTERNOON. THROUGH TUESDAY OF
NEXT WEEK...AN APPROACHING TROUGH FROM THE WEST WILL SUPPORT
CONTINUED SOUTHWESTERLY FLOW ALOFT AND MID-LEVEL MIXING RATIO VALUES
ARE FORECAST TO DIP BELOW 8 G/KG. A SUBTLE DRYING TREND AND
AN UNFAVORABLE MONSOON PATTERN LOOKS TO SETTLE IN THROUGH MID-WEEK
NEXT WEEK. TEMPERATURES WILL TREND UPWARD THROUGH THE WEEKEND AND
THEN HOLD ON TO PERSISTENCE NEAR SEASONAL AVERAGE THROUGH THE WEEK
AHEAD.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND

THROUGH 04Z FRI...SCT-NMRS TSTMS OVER THE DISTANT MOUNTAINS NORTH OF
PHOENIX WILL LIKELY GENERATE A SOUTHWARD MOVING OUTFLOW BOUNDARY
ACROSS THE PHOENIX METRO AREA. SINCE MONSOON MOISTURE IS RELATIVELY
HIGH FOR TODAY...THE SOUTHWARD MOVING OUTFLOW BOUNDARY WILL LIKELY
TRIGGER TSTMS ALONG AND JUST BEHIND THE BOUNDARY AS IT MOVES SOUTH
THRU THE PHOENIX VALLEY. TSTMS WILL DVLP IN THE VICINITY OF VALLEY
AIRPORTS. THEREFORE THROUGH 04Z FRI...SCT-BKN CLDS BASED 8 TO 10
THSD AGL WITH A FEW TSTMS AND GUSTY ERRATIC WINDS. FROM 04Z FRI TO
06Z FRI...SCT-BKN CLDS 8-10 THSD AGL WITH ISOLATED SHWRS. FROM 06Z
FRI TO 16Z FRI...SCT CLDS BASED 8 TO 10 THSD AGL WITH BKN HIGH
CLOUDS.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
THROUGH 07Z FRI...SCT CLDS 8 TO 10 THSD AGL. SOUTH TO SOUTHWEST WIND
8 TO 10 KNOTS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...

SATURDAY THROUGH WEDNESDAY...DRIER AND WARMER WEATHER WILL SPREAD
INTO REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...DEWEY
AVIATION...VASQUEZ
FIRE WEATHER...VASQUEZ/CB





000
FXUS65 KPSR 272012
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
110 PM MST THU AUG 27 2015

.UPDATE...AVIATION DISCUSSION.

&&

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD TODAY. STARTING
FRIDAY THE DRIER AIR WILL PUSH FURTHER EAST CONFINING RAIN CHANCES
TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH THE
WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION...
A SOUTHWEST FLOW ALOFT IS EVIDENTLY SEEN IN IR SATELLITE IMAGERY FROM
A LONG LOOP DURING THE OVERNIGHT HOURS TO CURRENT TIME...WITH CLOUDS
CLEARING ACROSS CENTRAL ARIZONA AND LOCATIONS ALONG THE RIM AND
SOUTHERN ARIZONA. A RATHER LARGE MCS FEATURE PRESENT OVERNIGHT ACROSS
FAR SOUTHERN SONORA WEAKENED AND MOVED NORTHWEST TOWARDS BAJA AFTER
15Z THIS MORNING...INTO AN AREA OF HIGHER PWAT VALUES. PER MORNING
RAOB SOUNDINGS FROM TUS...PSR AND 1Y7...AVAILABLE MOISTURE IS
CERTAINLY PRESENT AND MEASURING ABOVE AVERAGE FOR THIS TIME OF YEAR.
HOWEVER...A SOUTHWEST FLOW IS DEFINITELY IN PLACE ACROSS ALL AZ UPPER
AIR PLOTS. CONFLUENT FLOW ALOFT WILL LIKELY BE OUR CONVECTIVE
INHIBITOR FOR TODAY STORM WISE...AND WITH CLEARING SKIES AND
TEMPERATURES ALREADY RUNNING 4-6 DEGREES ABOVE THIS TIME
YESTERDAY...THERE ISN`T A DOUBT WE WILL SEE ANOTHER ABOVE AVERAGE
TEMPERATURE DAY ACROSS THE CENTRAL AND LOWER DESERTS. CURRENT
FORECAST IS IN GOOD SHAPE AT THIS TIME.

.PREVIOUS DISCUSSION.../300 AM MST 27 AUG/...
UPPER HIGH REMAINED FIRMLY ENTRENCHED OVER THE WEST- CENTRAL CONUS
THIS MORNING...WITH RELATIVELY HIGH H5 VALUES AROUND 594DM OVER MUCH
OF ARIZONA PER THE LATEST 00Z PLOT DATA. IR IMAGERY AT 2 AM SHOWED
DISSIPATING MID LEVEL DEBRIS CLOUD ACROSS SRN AZ WITH SKIES PARTLY
CLOUDY TO MOSTLY CLEAR OVER THE SRN DESERT. SURFACE DEWPOINTS OVER
THE DESERTS WERE A BIT ON THE HIGH SIDE...RANGING FROM THE UPPER 50S
TO MID 60S AT 2 AM. ALSO...LATEST RADAR SHOWED A FEW NEW STORMS
POPPING UP NORTH OF THE GREATER PHOENIX AREA...OVER THE CENTRAL
MOUNTAINS.

ALTHOUGH HEIGHTS ARE ON THE HIGH SIDE THE RIDGE WAS CENTERED WELL TO
THE SOUTHEAST OF PHOENIX...ROUGHLY ALONG THE AZ/NM BORDER AND NEAR
THE MEXICAN BORDER. THIS HAS PLACED A SOUTHWESTERLY FLOW ALOFT
ACROSS MOST OF THE STATE AND THIS IS AN UNFAVORABLE DIRECTION TO
BRING STORMS TO THE LOWER AZ DESERTS. OPERATIONAL MODELS AS WELL AS
ENSEMBLE GUIDANCE CONTINUES TO ADVERTISE A MOSTLY SOUTHWESTERLY
STEERING FLOW ACROSS OUR AREA FOR THE NEXT WEEK AS TROFFING ALOFT
SETS UP ALONG THE WEST COAST. THIS WILL CAUSE MOISTURE TO GRADUALLY
THIN OVER THE WESTERN DESERTS AND WILL LEAD TO LOW GRADE MONSOON
CONDITIONS WHERE STORMS WILL BE PRIMARILY CONFINED TO HIGHER TERRAIN
AREAS TO THE EAST OF PHOENIX. OPERATIONAL MODEL RUNS DO NOT
ADVERTISE ANY SIGNIFICANT INVERTED TROFS OR DISTURBANCES TO ROTATE
AROUND THE HIGH...OR TO MOVE THROUGH THE SOUTHWEST FLOW ALOFT...OVER
THE NEXT SEVERAL DAYS AT LEAST...AND WITHOUT ANY SIGNIFICANT FORCING
FEATURE TO CAUSE AN UPRAMP IN STORM CHANCES...THERE IS LITTLE REASON
TO FORECAST MUCH OUTSIDE OF LOW GRADE MONSOON CONDITIONS...OR CLIMO
TYPE POPS FOR THE 7 DAY FORECAST PERIOD.

FOR THE FIRST COUPLE OF DAYS...TODAY INTO FRIDAY...WITH H5 HEIGHTS
STAYING RATHER HIGH AND MOISTURE THINNING WE WILL BE LOOKING AT
HIGH TEMPERATURES WELL ABOVE SEASONAL NORMALS WITH THE HOTTER
WESTERN DESERTS REACHING OR EXCEEDING 110 DEGREES AND THE GREATER
PHOENIX AREA PUSHING 110. OVER THE WEEKEND AND INTO THE FIRST PART
OF NEXT WEEK AS TROFFING SETS UP ALONG THE WEST COAST AND HEIGHTS
FALL OFF...TEMPS WILL COOL STEADILY. BY EARLY NEXT WEEK HIGHS OVER
THE CENTRAL DESERTS WILL DROP TO LEVELS ONLY SLIGHTLY ABOVE SEASONAL
NORMALS WITH PHOENIX REACHING AROUND 104 BY NEXT MONDAY OR TUESDAY.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND

THROUGH 04Z FRI...SCT-NMRS TSTMS OVER THE DISTANT MOUNTAINS NORTH OF
PHOENIX WILL LIKELY GENERATE A SOUTHWARD MOVING OUTFLOW BOUNDARY
ACROSS THE PHOENIX METRO AREA. SINCE MONSOON MOISTURE IS RELATIVELY
HIGH FOR TODAY...THE SOUTHWARD MOVING OUTFLOW BOUNDARY WILL LIKELY
TRIGGER TSTMS ALONG AND JUST BEHIND THE BOUNDARY AS IT MOVES SOUTH
THRU THE PHOENIX VALLEY. TSTMS WILL DVLP IN THE VICINITY OF VALLEY
AIRPORTS. THEREFORE THROUGH 04Z FRI...SCT-BKN CLDS BASED 8 TO 10
THSD AGL WITH A FEW TSTMS AND GUSTY ERRATIC WINDS. FROM 04Z FRI TO
06Z FRI...SCT-BKN CLDS 8-10 THSD AGL WITH ISOLATED SHWRS. FROM 06Z
FRI TO 16Z FRI...SCT CLDS BASED 8 TO 10 THSD AGL WITH BKN HIGH
CLOUDS.


SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
THROUGH 07Z FRI...SCT CLDS 8 TO 10 THSD AGL. SOUTH TO SOUTHWEST WIND
8 TO 10 KNOTS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...

SATURDAY THROUGH WEDNESDAY...DRIER AND WARMER WEATHER WILL SPREAD
INTO REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...DEWEY
PREVIOUS DISCUSSION...CB
AVIATION...VASQUEZ
FIRE WEATHER...VASQUEZ/CB




000
FXUS65 KPSR 272012
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
110 PM MST THU AUG 27 2015

.UPDATE...AVIATION DISCUSSION.

&&

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD TODAY. STARTING
FRIDAY THE DRIER AIR WILL PUSH FURTHER EAST CONFINING RAIN CHANCES
TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH THE
WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION...
A SOUTHWEST FLOW ALOFT IS EVIDENTLY SEEN IN IR SATELLITE IMAGERY FROM
A LONG LOOP DURING THE OVERNIGHT HOURS TO CURRENT TIME...WITH CLOUDS
CLEARING ACROSS CENTRAL ARIZONA AND LOCATIONS ALONG THE RIM AND
SOUTHERN ARIZONA. A RATHER LARGE MCS FEATURE PRESENT OVERNIGHT ACROSS
FAR SOUTHERN SONORA WEAKENED AND MOVED NORTHWEST TOWARDS BAJA AFTER
15Z THIS MORNING...INTO AN AREA OF HIGHER PWAT VALUES. PER MORNING
RAOB SOUNDINGS FROM TUS...PSR AND 1Y7...AVAILABLE MOISTURE IS
CERTAINLY PRESENT AND MEASURING ABOVE AVERAGE FOR THIS TIME OF YEAR.
HOWEVER...A SOUTHWEST FLOW IS DEFINITELY IN PLACE ACROSS ALL AZ UPPER
AIR PLOTS. CONFLUENT FLOW ALOFT WILL LIKELY BE OUR CONVECTIVE
INHIBITOR FOR TODAY STORM WISE...AND WITH CLEARING SKIES AND
TEMPERATURES ALREADY RUNNING 4-6 DEGREES ABOVE THIS TIME
YESTERDAY...THERE ISN`T A DOUBT WE WILL SEE ANOTHER ABOVE AVERAGE
TEMPERATURE DAY ACROSS THE CENTRAL AND LOWER DESERTS. CURRENT
FORECAST IS IN GOOD SHAPE AT THIS TIME.

.PREVIOUS DISCUSSION.../300 AM MST 27 AUG/...
UPPER HIGH REMAINED FIRMLY ENTRENCHED OVER THE WEST- CENTRAL CONUS
THIS MORNING...WITH RELATIVELY HIGH H5 VALUES AROUND 594DM OVER MUCH
OF ARIZONA PER THE LATEST 00Z PLOT DATA. IR IMAGERY AT 2 AM SHOWED
DISSIPATING MID LEVEL DEBRIS CLOUD ACROSS SRN AZ WITH SKIES PARTLY
CLOUDY TO MOSTLY CLEAR OVER THE SRN DESERT. SURFACE DEWPOINTS OVER
THE DESERTS WERE A BIT ON THE HIGH SIDE...RANGING FROM THE UPPER 50S
TO MID 60S AT 2 AM. ALSO...LATEST RADAR SHOWED A FEW NEW STORMS
POPPING UP NORTH OF THE GREATER PHOENIX AREA...OVER THE CENTRAL
MOUNTAINS.

ALTHOUGH HEIGHTS ARE ON THE HIGH SIDE THE RIDGE WAS CENTERED WELL TO
THE SOUTHEAST OF PHOENIX...ROUGHLY ALONG THE AZ/NM BORDER AND NEAR
THE MEXICAN BORDER. THIS HAS PLACED A SOUTHWESTERLY FLOW ALOFT
ACROSS MOST OF THE STATE AND THIS IS AN UNFAVORABLE DIRECTION TO
BRING STORMS TO THE LOWER AZ DESERTS. OPERATIONAL MODELS AS WELL AS
ENSEMBLE GUIDANCE CONTINUES TO ADVERTISE A MOSTLY SOUTHWESTERLY
STEERING FLOW ACROSS OUR AREA FOR THE NEXT WEEK AS TROFFING ALOFT
SETS UP ALONG THE WEST COAST. THIS WILL CAUSE MOISTURE TO GRADUALLY
THIN OVER THE WESTERN DESERTS AND WILL LEAD TO LOW GRADE MONSOON
CONDITIONS WHERE STORMS WILL BE PRIMARILY CONFINED TO HIGHER TERRAIN
AREAS TO THE EAST OF PHOENIX. OPERATIONAL MODEL RUNS DO NOT
ADVERTISE ANY SIGNIFICANT INVERTED TROFS OR DISTURBANCES TO ROTATE
AROUND THE HIGH...OR TO MOVE THROUGH THE SOUTHWEST FLOW ALOFT...OVER
THE NEXT SEVERAL DAYS AT LEAST...AND WITHOUT ANY SIGNIFICANT FORCING
FEATURE TO CAUSE AN UPRAMP IN STORM CHANCES...THERE IS LITTLE REASON
TO FORECAST MUCH OUTSIDE OF LOW GRADE MONSOON CONDITIONS...OR CLIMO
TYPE POPS FOR THE 7 DAY FORECAST PERIOD.

FOR THE FIRST COUPLE OF DAYS...TODAY INTO FRIDAY...WITH H5 HEIGHTS
STAYING RATHER HIGH AND MOISTURE THINNING WE WILL BE LOOKING AT
HIGH TEMPERATURES WELL ABOVE SEASONAL NORMALS WITH THE HOTTER
WESTERN DESERTS REACHING OR EXCEEDING 110 DEGREES AND THE GREATER
PHOENIX AREA PUSHING 110. OVER THE WEEKEND AND INTO THE FIRST PART
OF NEXT WEEK AS TROFFING SETS UP ALONG THE WEST COAST AND HEIGHTS
FALL OFF...TEMPS WILL COOL STEADILY. BY EARLY NEXT WEEK HIGHS OVER
THE CENTRAL DESERTS WILL DROP TO LEVELS ONLY SLIGHTLY ABOVE SEASONAL
NORMALS WITH PHOENIX REACHING AROUND 104 BY NEXT MONDAY OR TUESDAY.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND

THROUGH 04Z FRI...SCT-NMRS TSTMS OVER THE DISTANT MOUNTAINS NORTH OF
PHOENIX WILL LIKELY GENERATE A SOUTHWARD MOVING OUTFLOW BOUNDARY
ACROSS THE PHOENIX METRO AREA. SINCE MONSOON MOISTURE IS RELATIVELY
HIGH FOR TODAY...THE SOUTHWARD MOVING OUTFLOW BOUNDARY WILL LIKELY
TRIGGER TSTMS ALONG AND JUST BEHIND THE BOUNDARY AS IT MOVES SOUTH
THRU THE PHOENIX VALLEY. TSTMS WILL DVLP IN THE VICINITY OF VALLEY
AIRPORTS. THEREFORE THROUGH 04Z FRI...SCT-BKN CLDS BASED 8 TO 10
THSD AGL WITH A FEW TSTMS AND GUSTY ERRATIC WINDS. FROM 04Z FRI TO
06Z FRI...SCT-BKN CLDS 8-10 THSD AGL WITH ISOLATED SHWRS. FROM 06Z
FRI TO 16Z FRI...SCT CLDS BASED 8 TO 10 THSD AGL WITH BKN HIGH
CLOUDS.


SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
THROUGH 07Z FRI...SCT CLDS 8 TO 10 THSD AGL. SOUTH TO SOUTHWEST WIND
8 TO 10 KNOTS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...

SATURDAY THROUGH WEDNESDAY...DRIER AND WARMER WEATHER WILL SPREAD
INTO REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...DEWEY
PREVIOUS DISCUSSION...CB
AVIATION...VASQUEZ
FIRE WEATHER...VASQUEZ/CB





000
FXUS65 KPSR 271621
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
921 AM MST THU AUG 27 2015

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD TODAY. STARTING
FRIDAY THE DRIER AIR WILL PUSH FURTHER EAST CONFINING RAIN CHANCES
TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH THE
WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION...
A SOUTHWEST FLOW ALOFT IS EVIDENTLY SEEN IN IR SATELLITE IMAGERY FROM
A LONG LOOP DURING THE OVERNIGHT HOURS TO CURRENT TIME...WITH CLOUDS
CLEARING ACROSS CENTRAL ARIZONA AND LOCATIONS ALONG THE RIM AND
SOUTHERN ARIZONA. A RATHER LARGE MCS FEATURE PRESENT OVERNIGHT ACROSS
FAR SOUTHERN SONORA WEAKENED AND MOVED NORTHWEST TOWARDS BAJA AFTER
15Z THIS MORNING...INTO AN AREA OF HIGHER PWAT VALUES. PER MORNING
RAOB SOUNDINGS FROM TUS...PSR AND 1Y7...AVAILABLE MOISTURE IS
CERTAINLY PRESENT AND MEASURING ABOVE AVERAGE FOR THIS TIME OF YEAR.
HOWEVER...A SOUTHWEST FLOW IS DEFINITELY IN PLACE ACROSS ALL AZ UPPER
AIR PLOTS. CONFLUENT FLOW ALOFT WILL LIKELY BE OUR CONVECTIVE
INHIBITOR FOR TODAY STORM WISE...AND WITH CLEARING SKIES AND
TEMPERATURES ALREADY RUNNING 4-6 DEGREES ABOVE THIS TIME
YESTERDAY...THERE ISN`T A DOUBT WE WILL SEE ANOTHER ABOVE AVERAGE
TEMPERATURE DAY ACROSS THE CENTRAL AND LOWER DESERTS. CURRENT
FORECAST IS IN GOOD SHAPE AT THIS TIME.

.PREVIOUS DISCUSSION.../300 AM MST 27 AUG/...
UPPER HIGH REMAINED FIRMLY ENTRENCHED OVER THE WEST- CENTRAL CONUS
THIS MORNING...WITH RELATIVELY HIGH H5 VALUES AROUND 594DM OVER MUCH
OF ARIZONA PER THE LATEST 00Z PLOT DATA. IR IMAGERY AT 2 AM SHOWED
DISSIPATING MID LEVEL DEBRIS CLOUD ACROSS SRN AZ WITH SKIES PARTLY
CLOUDY TO MOSTLY CLEAR OVER THE SRN DESERT. SURFACE DEWPOINTS OVER
THE DESERTS WERE A BIT ON THE HIGH SIDE...RANGING FROM THE UPPER 50S
TO MID 60S AT 2 AM. ALSO...LATEST RADAR SHOWED A FEW NEW STORMS
POPPING UP NORTH OF THE GREATER PHOENIX AREA...OVER THE CENTRAL
MOUNTAINS.

ALTHOUGH HEIGHTS ARE ON THE HIGH SIDE THE RIDGE WAS CENTERED WELL TO
THE SOUTHEAST OF PHOENIX...ROUGHLY ALONG THE AZ/NM BORDER AND NEAR
THE MEXICAN BORDER. THIS HAS PLACED A SOUTHWESTERLY FLOW ALOFT
ACROSS MOST OF THE STATE AND THIS IS AN UNFAVORABLE DIRECTION TO
BRING STORMS TO THE LOWER AZ DESERTS. OPERATIONAL MODELS AS WELL AS
ENSEMBLE GUIDANCE CONTINUES TO ADVERTISE A MOSTLY SOUTHWESTERLY
STEERING FLOW ACROSS OUR AREA FOR THE NEXT WEEK AS TROFFING ALOFT
SETS UP ALONG THE WEST COAST. THIS WILL CAUSE MOISTURE TO GRADUALLY
THIN OVER THE WESTERN DESERTS AND WILL LEAD TO LOW GRADE MONSOON
CONDITIONS WHERE STORMS WILL BE PRIMARILY CONFINED TO HIGHER TERRAIN
AREAS TO THE EAST OF PHOENIX. OPERATIONAL MODEL RUNS DO NOT
ADVERTISE ANY SIGNIFICANT INVERTED TROFS OR DISTURBANCES TO ROTATE
AROUND THE HIGH...OR TO MOVE THROUGH THE SOUTHWEST FLOW ALOFT...OVER
THE NEXT SEVERAL DAYS AT LEAST...AND WITHOUT ANY SIGNIFICANT FORCING
FEATURE TO CAUSE AN UPRAMP IN STORM CHANCES...THERE IS LITTLE REASON
TO FORECAST MUCH OUTSIDE OF LOW GRADE MONSOON CONDITIONS...OR CLIMO
TYPE POPS FOR THE 7 DAY FORECAST PERIOD.

FOR THE FIRST COUPLE OF DAYS...TODAY INTO FRIDAY...WITH H5 HEIGHTS
STAYING RATHER HIGH AND MOISTURE THINNING WE WILL BE LOOKING AT
HIGH TEMPERATURES WELL ABOVE SEASONAL NORMALS WITH THE HOTTER
WESTERN DESERTS REACHING OR EXCEEDING 110 DEGREES AND THE GREATER
PHOENIX AREA PUSHING 110. OVER THE WEEKEND AND INTO THE FIRST PART
OF NEXT WEEK AS TROFFING SETS UP ALONG THE WEST COAST AND HEIGHTS
FALL OFF...TEMPS WILL COOL STEADILY. BY EARLY NEXT WEEK HIGHS OVER
THE CENTRAL DESERTS WILL DROP TO LEVELS ONLY SLIGHTLY ABOVE SEASONAL
NORMALS WITH PHOENIX REACHING AROUND 104 BY NEXT MONDAY OR TUESDAY.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

MAINLY FEW-SCT MID-HIGH LEVEL CLOUDS AND LIGHT WINDS 10KT OR LESS
EXPECTED AT ALL TAF SITES. SKIES BECOME SCT-BKN AOA 10KFT ACROSS
SOUTH-CENTRAL AZ...AND THUNDERSTORM ACTIVITY WILL PICK UP AFTER 18Z
OVER THE MOUNTAINS AND HIGHER TERRAIN WELL EAST/NORTH OF PHOENIX...
WITH SKIES REMAINING MOSTLY CLEAR ACROSS SOUTHEAST CALIFORNIA.
POSSIBLE FOR AN ISOLATED STORM TO FORM OVER THE LOWER CENTRAL
DESERTS AND GUSTY OUTFLOWS TO IMPACT KPHX/KIWA/KSDL LATER THIS
AFTERNOON AND EVENING...BUT SOUTHWESTERLY STEERING FLOWS SHOULD KEEP
BULK OF STORMS AWAY FROM TAF SITES.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...

SATURDAY THROUGH WEDNESDAY...DRIER AND WARMER WEATHER WILL SPREAD
INTO REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...DEWEY
PREVIOUS DISCUSSION...CB
AVIATION...MEYERS
FIRE WEATHER...VASQUEZ/CB





000
FXUS65 KPSR 271621
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
921 AM MST THU AUG 27 2015

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD TODAY. STARTING
FRIDAY THE DRIER AIR WILL PUSH FURTHER EAST CONFINING RAIN CHANCES
TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH THE
WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION...
A SOUTHWEST FLOW ALOFT IS EVIDENTLY SEEN IN IR SATELLITE IMAGERY FROM
A LONG LOOP DURING THE OVERNIGHT HOURS TO CURRENT TIME...WITH CLOUDS
CLEARING ACROSS CENTRAL ARIZONA AND LOCATIONS ALONG THE RIM AND
SOUTHERN ARIZONA. A RATHER LARGE MCS FEATURE PRESENT OVERNIGHT ACROSS
FAR SOUTHERN SONORA WEAKENED AND MOVED NORTHWEST TOWARDS BAJA AFTER
15Z THIS MORNING...INTO AN AREA OF HIGHER PWAT VALUES. PER MORNING
RAOB SOUNDINGS FROM TUS...PSR AND 1Y7...AVAILABLE MOISTURE IS
CERTAINLY PRESENT AND MEASURING ABOVE AVERAGE FOR THIS TIME OF YEAR.
HOWEVER...A SOUTHWEST FLOW IS DEFINITELY IN PLACE ACROSS ALL AZ UPPER
AIR PLOTS. CONFLUENT FLOW ALOFT WILL LIKELY BE OUR CONVECTIVE
INHIBITOR FOR TODAY STORM WISE...AND WITH CLEARING SKIES AND
TEMPERATURES ALREADY RUNNING 4-6 DEGREES ABOVE THIS TIME
YESTERDAY...THERE ISN`T A DOUBT WE WILL SEE ANOTHER ABOVE AVERAGE
TEMPERATURE DAY ACROSS THE CENTRAL AND LOWER DESERTS. CURRENT
FORECAST IS IN GOOD SHAPE AT THIS TIME.

.PREVIOUS DISCUSSION.../300 AM MST 27 AUG/...
UPPER HIGH REMAINED FIRMLY ENTRENCHED OVER THE WEST- CENTRAL CONUS
THIS MORNING...WITH RELATIVELY HIGH H5 VALUES AROUND 594DM OVER MUCH
OF ARIZONA PER THE LATEST 00Z PLOT DATA. IR IMAGERY AT 2 AM SHOWED
DISSIPATING MID LEVEL DEBRIS CLOUD ACROSS SRN AZ WITH SKIES PARTLY
CLOUDY TO MOSTLY CLEAR OVER THE SRN DESERT. SURFACE DEWPOINTS OVER
THE DESERTS WERE A BIT ON THE HIGH SIDE...RANGING FROM THE UPPER 50S
TO MID 60S AT 2 AM. ALSO...LATEST RADAR SHOWED A FEW NEW STORMS
POPPING UP NORTH OF THE GREATER PHOENIX AREA...OVER THE CENTRAL
MOUNTAINS.

ALTHOUGH HEIGHTS ARE ON THE HIGH SIDE THE RIDGE WAS CENTERED WELL TO
THE SOUTHEAST OF PHOENIX...ROUGHLY ALONG THE AZ/NM BORDER AND NEAR
THE MEXICAN BORDER. THIS HAS PLACED A SOUTHWESTERLY FLOW ALOFT
ACROSS MOST OF THE STATE AND THIS IS AN UNFAVORABLE DIRECTION TO
BRING STORMS TO THE LOWER AZ DESERTS. OPERATIONAL MODELS AS WELL AS
ENSEMBLE GUIDANCE CONTINUES TO ADVERTISE A MOSTLY SOUTHWESTERLY
STEERING FLOW ACROSS OUR AREA FOR THE NEXT WEEK AS TROFFING ALOFT
SETS UP ALONG THE WEST COAST. THIS WILL CAUSE MOISTURE TO GRADUALLY
THIN OVER THE WESTERN DESERTS AND WILL LEAD TO LOW GRADE MONSOON
CONDITIONS WHERE STORMS WILL BE PRIMARILY CONFINED TO HIGHER TERRAIN
AREAS TO THE EAST OF PHOENIX. OPERATIONAL MODEL RUNS DO NOT
ADVERTISE ANY SIGNIFICANT INVERTED TROFS OR DISTURBANCES TO ROTATE
AROUND THE HIGH...OR TO MOVE THROUGH THE SOUTHWEST FLOW ALOFT...OVER
THE NEXT SEVERAL DAYS AT LEAST...AND WITHOUT ANY SIGNIFICANT FORCING
FEATURE TO CAUSE AN UPRAMP IN STORM CHANCES...THERE IS LITTLE REASON
TO FORECAST MUCH OUTSIDE OF LOW GRADE MONSOON CONDITIONS...OR CLIMO
TYPE POPS FOR THE 7 DAY FORECAST PERIOD.

FOR THE FIRST COUPLE OF DAYS...TODAY INTO FRIDAY...WITH H5 HEIGHTS
STAYING RATHER HIGH AND MOISTURE THINNING WE WILL BE LOOKING AT
HIGH TEMPERATURES WELL ABOVE SEASONAL NORMALS WITH THE HOTTER
WESTERN DESERTS REACHING OR EXCEEDING 110 DEGREES AND THE GREATER
PHOENIX AREA PUSHING 110. OVER THE WEEKEND AND INTO THE FIRST PART
OF NEXT WEEK AS TROFFING SETS UP ALONG THE WEST COAST AND HEIGHTS
FALL OFF...TEMPS WILL COOL STEADILY. BY EARLY NEXT WEEK HIGHS OVER
THE CENTRAL DESERTS WILL DROP TO LEVELS ONLY SLIGHTLY ABOVE SEASONAL
NORMALS WITH PHOENIX REACHING AROUND 104 BY NEXT MONDAY OR TUESDAY.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

MAINLY FEW-SCT MID-HIGH LEVEL CLOUDS AND LIGHT WINDS 10KT OR LESS
EXPECTED AT ALL TAF SITES. SKIES BECOME SCT-BKN AOA 10KFT ACROSS
SOUTH-CENTRAL AZ...AND THUNDERSTORM ACTIVITY WILL PICK UP AFTER 18Z
OVER THE MOUNTAINS AND HIGHER TERRAIN WELL EAST/NORTH OF PHOENIX...
WITH SKIES REMAINING MOSTLY CLEAR ACROSS SOUTHEAST CALIFORNIA.
POSSIBLE FOR AN ISOLATED STORM TO FORM OVER THE LOWER CENTRAL
DESERTS AND GUSTY OUTFLOWS TO IMPACT KPHX/KIWA/KSDL LATER THIS
AFTERNOON AND EVENING...BUT SOUTHWESTERLY STEERING FLOWS SHOULD KEEP
BULK OF STORMS AWAY FROM TAF SITES.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...

SATURDAY THROUGH WEDNESDAY...DRIER AND WARMER WEATHER WILL SPREAD
INTO REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...DEWEY
PREVIOUS DISCUSSION...CB
AVIATION...MEYERS
FIRE WEATHER...VASQUEZ/CB




000
FXUS65 KPSR 271621
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
921 AM MST THU AUG 27 2015

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD TODAY. STARTING
FRIDAY THE DRIER AIR WILL PUSH FURTHER EAST CONFINING RAIN CHANCES
TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH THE
WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION...
A SOUTHWEST FLOW ALOFT IS EVIDENTLY SEEN IN IR SATELLITE IMAGERY FROM
A LONG LOOP DURING THE OVERNIGHT HOURS TO CURRENT TIME...WITH CLOUDS
CLEARING ACROSS CENTRAL ARIZONA AND LOCATIONS ALONG THE RIM AND
SOUTHERN ARIZONA. A RATHER LARGE MCS FEATURE PRESENT OVERNIGHT ACROSS
FAR SOUTHERN SONORA WEAKENED AND MOVED NORTHWEST TOWARDS BAJA AFTER
15Z THIS MORNING...INTO AN AREA OF HIGHER PWAT VALUES. PER MORNING
RAOB SOUNDINGS FROM TUS...PSR AND 1Y7...AVAILABLE MOISTURE IS
CERTAINLY PRESENT AND MEASURING ABOVE AVERAGE FOR THIS TIME OF YEAR.
HOWEVER...A SOUTHWEST FLOW IS DEFINITELY IN PLACE ACROSS ALL AZ UPPER
AIR PLOTS. CONFLUENT FLOW ALOFT WILL LIKELY BE OUR CONVECTIVE
INHIBITOR FOR TODAY STORM WISE...AND WITH CLEARING SKIES AND
TEMPERATURES ALREADY RUNNING 4-6 DEGREES ABOVE THIS TIME
YESTERDAY...THERE ISN`T A DOUBT WE WILL SEE ANOTHER ABOVE AVERAGE
TEMPERATURE DAY ACROSS THE CENTRAL AND LOWER DESERTS. CURRENT
FORECAST IS IN GOOD SHAPE AT THIS TIME.

.PREVIOUS DISCUSSION.../300 AM MST 27 AUG/...
UPPER HIGH REMAINED FIRMLY ENTRENCHED OVER THE WEST- CENTRAL CONUS
THIS MORNING...WITH RELATIVELY HIGH H5 VALUES AROUND 594DM OVER MUCH
OF ARIZONA PER THE LATEST 00Z PLOT DATA. IR IMAGERY AT 2 AM SHOWED
DISSIPATING MID LEVEL DEBRIS CLOUD ACROSS SRN AZ WITH SKIES PARTLY
CLOUDY TO MOSTLY CLEAR OVER THE SRN DESERT. SURFACE DEWPOINTS OVER
THE DESERTS WERE A BIT ON THE HIGH SIDE...RANGING FROM THE UPPER 50S
TO MID 60S AT 2 AM. ALSO...LATEST RADAR SHOWED A FEW NEW STORMS
POPPING UP NORTH OF THE GREATER PHOENIX AREA...OVER THE CENTRAL
MOUNTAINS.

ALTHOUGH HEIGHTS ARE ON THE HIGH SIDE THE RIDGE WAS CENTERED WELL TO
THE SOUTHEAST OF PHOENIX...ROUGHLY ALONG THE AZ/NM BORDER AND NEAR
THE MEXICAN BORDER. THIS HAS PLACED A SOUTHWESTERLY FLOW ALOFT
ACROSS MOST OF THE STATE AND THIS IS AN UNFAVORABLE DIRECTION TO
BRING STORMS TO THE LOWER AZ DESERTS. OPERATIONAL MODELS AS WELL AS
ENSEMBLE GUIDANCE CONTINUES TO ADVERTISE A MOSTLY SOUTHWESTERLY
STEERING FLOW ACROSS OUR AREA FOR THE NEXT WEEK AS TROFFING ALOFT
SETS UP ALONG THE WEST COAST. THIS WILL CAUSE MOISTURE TO GRADUALLY
THIN OVER THE WESTERN DESERTS AND WILL LEAD TO LOW GRADE MONSOON
CONDITIONS WHERE STORMS WILL BE PRIMARILY CONFINED TO HIGHER TERRAIN
AREAS TO THE EAST OF PHOENIX. OPERATIONAL MODEL RUNS DO NOT
ADVERTISE ANY SIGNIFICANT INVERTED TROFS OR DISTURBANCES TO ROTATE
AROUND THE HIGH...OR TO MOVE THROUGH THE SOUTHWEST FLOW ALOFT...OVER
THE NEXT SEVERAL DAYS AT LEAST...AND WITHOUT ANY SIGNIFICANT FORCING
FEATURE TO CAUSE AN UPRAMP IN STORM CHANCES...THERE IS LITTLE REASON
TO FORECAST MUCH OUTSIDE OF LOW GRADE MONSOON CONDITIONS...OR CLIMO
TYPE POPS FOR THE 7 DAY FORECAST PERIOD.

FOR THE FIRST COUPLE OF DAYS...TODAY INTO FRIDAY...WITH H5 HEIGHTS
STAYING RATHER HIGH AND MOISTURE THINNING WE WILL BE LOOKING AT
HIGH TEMPERATURES WELL ABOVE SEASONAL NORMALS WITH THE HOTTER
WESTERN DESERTS REACHING OR EXCEEDING 110 DEGREES AND THE GREATER
PHOENIX AREA PUSHING 110. OVER THE WEEKEND AND INTO THE FIRST PART
OF NEXT WEEK AS TROFFING SETS UP ALONG THE WEST COAST AND HEIGHTS
FALL OFF...TEMPS WILL COOL STEADILY. BY EARLY NEXT WEEK HIGHS OVER
THE CENTRAL DESERTS WILL DROP TO LEVELS ONLY SLIGHTLY ABOVE SEASONAL
NORMALS WITH PHOENIX REACHING AROUND 104 BY NEXT MONDAY OR TUESDAY.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

MAINLY FEW-SCT MID-HIGH LEVEL CLOUDS AND LIGHT WINDS 10KT OR LESS
EXPECTED AT ALL TAF SITES. SKIES BECOME SCT-BKN AOA 10KFT ACROSS
SOUTH-CENTRAL AZ...AND THUNDERSTORM ACTIVITY WILL PICK UP AFTER 18Z
OVER THE MOUNTAINS AND HIGHER TERRAIN WELL EAST/NORTH OF PHOENIX...
WITH SKIES REMAINING MOSTLY CLEAR ACROSS SOUTHEAST CALIFORNIA.
POSSIBLE FOR AN ISOLATED STORM TO FORM OVER THE LOWER CENTRAL
DESERTS AND GUSTY OUTFLOWS TO IMPACT KPHX/KIWA/KSDL LATER THIS
AFTERNOON AND EVENING...BUT SOUTHWESTERLY STEERING FLOWS SHOULD KEEP
BULK OF STORMS AWAY FROM TAF SITES.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...

SATURDAY THROUGH WEDNESDAY...DRIER AND WARMER WEATHER WILL SPREAD
INTO REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...DEWEY
PREVIOUS DISCUSSION...CB
AVIATION...MEYERS
FIRE WEATHER...VASQUEZ/CB




000
FXUS65 KPSR 271621
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
921 AM MST THU AUG 27 2015

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD TODAY. STARTING
FRIDAY THE DRIER AIR WILL PUSH FURTHER EAST CONFINING RAIN CHANCES
TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH THE
WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION...
A SOUTHWEST FLOW ALOFT IS EVIDENTLY SEEN IN IR SATELLITE IMAGERY FROM
A LONG LOOP DURING THE OVERNIGHT HOURS TO CURRENT TIME...WITH CLOUDS
CLEARING ACROSS CENTRAL ARIZONA AND LOCATIONS ALONG THE RIM AND
SOUTHERN ARIZONA. A RATHER LARGE MCS FEATURE PRESENT OVERNIGHT ACROSS
FAR SOUTHERN SONORA WEAKENED AND MOVED NORTHWEST TOWARDS BAJA AFTER
15Z THIS MORNING...INTO AN AREA OF HIGHER PWAT VALUES. PER MORNING
RAOB SOUNDINGS FROM TUS...PSR AND 1Y7...AVAILABLE MOISTURE IS
CERTAINLY PRESENT AND MEASURING ABOVE AVERAGE FOR THIS TIME OF YEAR.
HOWEVER...A SOUTHWEST FLOW IS DEFINITELY IN PLACE ACROSS ALL AZ UPPER
AIR PLOTS. CONFLUENT FLOW ALOFT WILL LIKELY BE OUR CONVECTIVE
INHIBITOR FOR TODAY STORM WISE...AND WITH CLEARING SKIES AND
TEMPERATURES ALREADY RUNNING 4-6 DEGREES ABOVE THIS TIME
YESTERDAY...THERE ISN`T A DOUBT WE WILL SEE ANOTHER ABOVE AVERAGE
TEMPERATURE DAY ACROSS THE CENTRAL AND LOWER DESERTS. CURRENT
FORECAST IS IN GOOD SHAPE AT THIS TIME.

.PREVIOUS DISCUSSION.../300 AM MST 27 AUG/...
UPPER HIGH REMAINED FIRMLY ENTRENCHED OVER THE WEST- CENTRAL CONUS
THIS MORNING...WITH RELATIVELY HIGH H5 VALUES AROUND 594DM OVER MUCH
OF ARIZONA PER THE LATEST 00Z PLOT DATA. IR IMAGERY AT 2 AM SHOWED
DISSIPATING MID LEVEL DEBRIS CLOUD ACROSS SRN AZ WITH SKIES PARTLY
CLOUDY TO MOSTLY CLEAR OVER THE SRN DESERT. SURFACE DEWPOINTS OVER
THE DESERTS WERE A BIT ON THE HIGH SIDE...RANGING FROM THE UPPER 50S
TO MID 60S AT 2 AM. ALSO...LATEST RADAR SHOWED A FEW NEW STORMS
POPPING UP NORTH OF THE GREATER PHOENIX AREA...OVER THE CENTRAL
MOUNTAINS.

ALTHOUGH HEIGHTS ARE ON THE HIGH SIDE THE RIDGE WAS CENTERED WELL TO
THE SOUTHEAST OF PHOENIX...ROUGHLY ALONG THE AZ/NM BORDER AND NEAR
THE MEXICAN BORDER. THIS HAS PLACED A SOUTHWESTERLY FLOW ALOFT
ACROSS MOST OF THE STATE AND THIS IS AN UNFAVORABLE DIRECTION TO
BRING STORMS TO THE LOWER AZ DESERTS. OPERATIONAL MODELS AS WELL AS
ENSEMBLE GUIDANCE CONTINUES TO ADVERTISE A MOSTLY SOUTHWESTERLY
STEERING FLOW ACROSS OUR AREA FOR THE NEXT WEEK AS TROFFING ALOFT
SETS UP ALONG THE WEST COAST. THIS WILL CAUSE MOISTURE TO GRADUALLY
THIN OVER THE WESTERN DESERTS AND WILL LEAD TO LOW GRADE MONSOON
CONDITIONS WHERE STORMS WILL BE PRIMARILY CONFINED TO HIGHER TERRAIN
AREAS TO THE EAST OF PHOENIX. OPERATIONAL MODEL RUNS DO NOT
ADVERTISE ANY SIGNIFICANT INVERTED TROFS OR DISTURBANCES TO ROTATE
AROUND THE HIGH...OR TO MOVE THROUGH THE SOUTHWEST FLOW ALOFT...OVER
THE NEXT SEVERAL DAYS AT LEAST...AND WITHOUT ANY SIGNIFICANT FORCING
FEATURE TO CAUSE AN UPRAMP IN STORM CHANCES...THERE IS LITTLE REASON
TO FORECAST MUCH OUTSIDE OF LOW GRADE MONSOON CONDITIONS...OR CLIMO
TYPE POPS FOR THE 7 DAY FORECAST PERIOD.

FOR THE FIRST COUPLE OF DAYS...TODAY INTO FRIDAY...WITH H5 HEIGHTS
STAYING RATHER HIGH AND MOISTURE THINNING WE WILL BE LOOKING AT
HIGH TEMPERATURES WELL ABOVE SEASONAL NORMALS WITH THE HOTTER
WESTERN DESERTS REACHING OR EXCEEDING 110 DEGREES AND THE GREATER
PHOENIX AREA PUSHING 110. OVER THE WEEKEND AND INTO THE FIRST PART
OF NEXT WEEK AS TROFFING SETS UP ALONG THE WEST COAST AND HEIGHTS
FALL OFF...TEMPS WILL COOL STEADILY. BY EARLY NEXT WEEK HIGHS OVER
THE CENTRAL DESERTS WILL DROP TO LEVELS ONLY SLIGHTLY ABOVE SEASONAL
NORMALS WITH PHOENIX REACHING AROUND 104 BY NEXT MONDAY OR TUESDAY.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

MAINLY FEW-SCT MID-HIGH LEVEL CLOUDS AND LIGHT WINDS 10KT OR LESS
EXPECTED AT ALL TAF SITES. SKIES BECOME SCT-BKN AOA 10KFT ACROSS
SOUTH-CENTRAL AZ...AND THUNDERSTORM ACTIVITY WILL PICK UP AFTER 18Z
OVER THE MOUNTAINS AND HIGHER TERRAIN WELL EAST/NORTH OF PHOENIX...
WITH SKIES REMAINING MOSTLY CLEAR ACROSS SOUTHEAST CALIFORNIA.
POSSIBLE FOR AN ISOLATED STORM TO FORM OVER THE LOWER CENTRAL
DESERTS AND GUSTY OUTFLOWS TO IMPACT KPHX/KIWA/KSDL LATER THIS
AFTERNOON AND EVENING...BUT SOUTHWESTERLY STEERING FLOWS SHOULD KEEP
BULK OF STORMS AWAY FROM TAF SITES.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...

SATURDAY THROUGH WEDNESDAY...DRIER AND WARMER WEATHER WILL SPREAD
INTO REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...DEWEY
PREVIOUS DISCUSSION...CB
AVIATION...MEYERS
FIRE WEATHER...VASQUEZ/CB





000
FXUS65 KPSR 271313 AAA
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
610 AM MST THU AUG 27 2015

.UPDATE...UPDATED AVIATION DISCUSSION.

&&

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD TODAY. STARTING
FRIDAY THE DRIER AIR WILL PUSH FURTHER EAST CONFINING RAIN CHANCES
TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH THE
WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION...
UPPER HIGH REMAINED FIRMLY ENTRENCHED OVER THE WEST-CENTRAL CONUS
THIS MORNING...WITH RELATIVELY HIGH H5 VALUES AROUND  594DM OVER
MUCH OF ARIZONA PER THE LATEST 00Z PLOT DATA. IR IMAGERY AT 2 AM
SHOWED DISSIPATING MID LEVEL DEBRIS CLOUD ACROSS SRN AZ WITH SKIES
PARTLY CLOUDY TO MOSTLY CLEAR OVER THE SRN DESERT. SURFACE DEWPOINTS
OVER THE DESERTS WERE A BIT ON THE HIGH SIDE...RANGING FROM THE
UPPER 50S TO MID 60S AT 2 AM. ALSO...LATEST RADAR SHOWED A FEW NEW
STORMS POPPING UP NORTH OF THE GREATER PHOENIX AREA...OVER THE
CENTRAL MOUNTAINS.

ALTHOUGH HEIGHTS ARE ON THE HIGH SIDE THE RIDGE WAS CENTERED WELL TO
THE SOUTHEAST OF PHOENIX...ROUGHLY ALONG THE AZ/NM BORDER AND NEAR
THE MEXICAN BORDER. THIS HAS PLACED A SOUTHWESTERLY FLOW ALOFT
ACROSS MOST OF THE STATE AND THIS IS AN UNFAVORABLE DIRECTION TO
BRING STORMS TO THE LOWER AZ DESERTS. OPERATIONAL MODELS AS WELL AS
ENSEMBLE GUIDANCE CONTINUES TO ADVERTISE A MOSTLY SOUTHWESTERLY
STEERING FLOW ACROSS OUR AREA FOR THE NEXT WEEK AS TROFFING ALOFT
SETS UP ALONG THE WEST COAST. THIS WILL CAUSE MOISTURE TO GRADUALLY
THIN OVER THE WESTERN DESERTS AND WILL LEAD TO LOW GRADE MONSOON
CONDITIONS WHERE STORMS WILL BE PRIMARILY CONFINED TO HIGHER TERRAIN
AREAS TO THE EAST OF PHOENIX. OPERATIONAL MODEL RUNS DO NOT
ADVERTISE ANY SIGNIFICANT INVERTED TROFS OR DISTURBANCES TO ROTATE
AROUND THE HIGH...OR TO MOVE THROUGH THE SOUTHWEST FLOW ALOFT...OVER
THE NEXT SEVERAL DAYS AT LEAST...AND WITHOUT ANY SIGNIFICANT FORCING
FEATURE TO CAUSE AN UPRAMP IN STORM CHANCES...THERE IS LITTLE REASON
TO FORECAST MUCH OUTSIDE OF LOW GRADE MONSOON CONDITIONS...OR CLIMO
TYPE POPS FOR THE 7 DAY FORECAST PERIOD.

FOR THE FIRST COUPLE OF DAYS...TODAY INTO FRIDAY...WITH H5 HEIGHTS
STAYING RATHER HIGH AND MOISTURE THINNING WE WILL BE LOOKING AT
HIGH TEMPERATURES WELL ABOVE SEASONAL NORMALS WITH THE HOTTER
WESTERN DESERTS REACHING OR EXCEEDING 110 DEGREES AND THE GREATER
PHOENIX AREA PUSHING 110. OVER THE WEEKEND AND INTO THE FIRST PART
OF NEXT WEEK AS TROFFING SETS UP ALONG THE WEST COAST AND HEIGHTS
FALL OFF...TEMPS WILL COOL STEADILY. BY EARLY NEXT WEEK HIGHS OVER
THE CENTRAL DESERTS WILL DROP TO LEVELS ONLY SLIGHTLY ABOVE SEASONAL
NORMALS WITH PHOENIX REACHING AROUND 104 BY NEXT MONDAY OR TUESDAY.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

MAINLY FEW-SCT MID-HIGH LEVEL CLOUDS AND LIGHT WINDS 10KT OR LESS
EXPECTED AT ALL TAF SITES. SKIES BECOME SCT-BKN AOA 10KFT ACROSS
SOUTH-CENTRAL AZ...AND THUNDERSTORM ACTIVITY WILL PICK UP AFTER 18Z
OVER THE MOUNTAINS AND HIGHER TERRAIN WELL EAST/NORTH OF PHOENIX...
WITH SKIES REMAINING MOSTLY CLEAR ACROSS SOUTHEAST CALIFORNIA.
POSSIBLE FOR AN ISOLATED STORM TO FORM OVER THE LOWER CENTRAL
DESERTS AND GUSTY OUTFLOWS TO IMPACT KPHX/KIWA/KSDL LATER THIS
AFTERNOON AND EVENING...BUT SOUTHWESTERLY STEERING FLOWS SHOULD KEEP
BULK OF STORMS AWAY FROM TAF SITES.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...

SATURDAY THROUGH WEDNESDAY...DRIER AND WARMER WEATHER WILL SPREAD
INTO REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...CB
AVIATION...MEYERS
FIRE WEATHER...VASQUEZ/CB




000
FXUS65 KPSR 271313 AAA
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
610 AM MST THU AUG 27 2015

.UPDATE...UPDATED AVIATION DISCUSSION.

&&

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD TODAY. STARTING
FRIDAY THE DRIER AIR WILL PUSH FURTHER EAST CONFINING RAIN CHANCES
TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH THE
WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION...
UPPER HIGH REMAINED FIRMLY ENTRENCHED OVER THE WEST-CENTRAL CONUS
THIS MORNING...WITH RELATIVELY HIGH H5 VALUES AROUND  594DM OVER
MUCH OF ARIZONA PER THE LATEST 00Z PLOT DATA. IR IMAGERY AT 2 AM
SHOWED DISSIPATING MID LEVEL DEBRIS CLOUD ACROSS SRN AZ WITH SKIES
PARTLY CLOUDY TO MOSTLY CLEAR OVER THE SRN DESERT. SURFACE DEWPOINTS
OVER THE DESERTS WERE A BIT ON THE HIGH SIDE...RANGING FROM THE
UPPER 50S TO MID 60S AT 2 AM. ALSO...LATEST RADAR SHOWED A FEW NEW
STORMS POPPING UP NORTH OF THE GREATER PHOENIX AREA...OVER THE
CENTRAL MOUNTAINS.

ALTHOUGH HEIGHTS ARE ON THE HIGH SIDE THE RIDGE WAS CENTERED WELL TO
THE SOUTHEAST OF PHOENIX...ROUGHLY ALONG THE AZ/NM BORDER AND NEAR
THE MEXICAN BORDER. THIS HAS PLACED A SOUTHWESTERLY FLOW ALOFT
ACROSS MOST OF THE STATE AND THIS IS AN UNFAVORABLE DIRECTION TO
BRING STORMS TO THE LOWER AZ DESERTS. OPERATIONAL MODELS AS WELL AS
ENSEMBLE GUIDANCE CONTINUES TO ADVERTISE A MOSTLY SOUTHWESTERLY
STEERING FLOW ACROSS OUR AREA FOR THE NEXT WEEK AS TROFFING ALOFT
SETS UP ALONG THE WEST COAST. THIS WILL CAUSE MOISTURE TO GRADUALLY
THIN OVER THE WESTERN DESERTS AND WILL LEAD TO LOW GRADE MONSOON
CONDITIONS WHERE STORMS WILL BE PRIMARILY CONFINED TO HIGHER TERRAIN
AREAS TO THE EAST OF PHOENIX. OPERATIONAL MODEL RUNS DO NOT
ADVERTISE ANY SIGNIFICANT INVERTED TROFS OR DISTURBANCES TO ROTATE
AROUND THE HIGH...OR TO MOVE THROUGH THE SOUTHWEST FLOW ALOFT...OVER
THE NEXT SEVERAL DAYS AT LEAST...AND WITHOUT ANY SIGNIFICANT FORCING
FEATURE TO CAUSE AN UPRAMP IN STORM CHANCES...THERE IS LITTLE REASON
TO FORECAST MUCH OUTSIDE OF LOW GRADE MONSOON CONDITIONS...OR CLIMO
TYPE POPS FOR THE 7 DAY FORECAST PERIOD.

FOR THE FIRST COUPLE OF DAYS...TODAY INTO FRIDAY...WITH H5 HEIGHTS
STAYING RATHER HIGH AND MOISTURE THINNING WE WILL BE LOOKING AT
HIGH TEMPERATURES WELL ABOVE SEASONAL NORMALS WITH THE HOTTER
WESTERN DESERTS REACHING OR EXCEEDING 110 DEGREES AND THE GREATER
PHOENIX AREA PUSHING 110. OVER THE WEEKEND AND INTO THE FIRST PART
OF NEXT WEEK AS TROFFING SETS UP ALONG THE WEST COAST AND HEIGHTS
FALL OFF...TEMPS WILL COOL STEADILY. BY EARLY NEXT WEEK HIGHS OVER
THE CENTRAL DESERTS WILL DROP TO LEVELS ONLY SLIGHTLY ABOVE SEASONAL
NORMALS WITH PHOENIX REACHING AROUND 104 BY NEXT MONDAY OR TUESDAY.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

MAINLY FEW-SCT MID-HIGH LEVEL CLOUDS AND LIGHT WINDS 10KT OR LESS
EXPECTED AT ALL TAF SITES. SKIES BECOME SCT-BKN AOA 10KFT ACROSS
SOUTH-CENTRAL AZ...AND THUNDERSTORM ACTIVITY WILL PICK UP AFTER 18Z
OVER THE MOUNTAINS AND HIGHER TERRAIN WELL EAST/NORTH OF PHOENIX...
WITH SKIES REMAINING MOSTLY CLEAR ACROSS SOUTHEAST CALIFORNIA.
POSSIBLE FOR AN ISOLATED STORM TO FORM OVER THE LOWER CENTRAL
DESERTS AND GUSTY OUTFLOWS TO IMPACT KPHX/KIWA/KSDL LATER THIS
AFTERNOON AND EVENING...BUT SOUTHWESTERLY STEERING FLOWS SHOULD KEEP
BULK OF STORMS AWAY FROM TAF SITES.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...

SATURDAY THROUGH WEDNESDAY...DRIER AND WARMER WEATHER WILL SPREAD
INTO REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...CB
AVIATION...MEYERS
FIRE WEATHER...VASQUEZ/CB




000
FXUS65 KPSR 271313 AAA
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
610 AM MST THU AUG 27 2015

.UPDATE...UPDATED AVIATION DISCUSSION.

&&

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD TODAY. STARTING
FRIDAY THE DRIER AIR WILL PUSH FURTHER EAST CONFINING RAIN CHANCES
TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH THE
WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION...
UPPER HIGH REMAINED FIRMLY ENTRENCHED OVER THE WEST-CENTRAL CONUS
THIS MORNING...WITH RELATIVELY HIGH H5 VALUES AROUND  594DM OVER
MUCH OF ARIZONA PER THE LATEST 00Z PLOT DATA. IR IMAGERY AT 2 AM
SHOWED DISSIPATING MID LEVEL DEBRIS CLOUD ACROSS SRN AZ WITH SKIES
PARTLY CLOUDY TO MOSTLY CLEAR OVER THE SRN DESERT. SURFACE DEWPOINTS
OVER THE DESERTS WERE A BIT ON THE HIGH SIDE...RANGING FROM THE
UPPER 50S TO MID 60S AT 2 AM. ALSO...LATEST RADAR SHOWED A FEW NEW
STORMS POPPING UP NORTH OF THE GREATER PHOENIX AREA...OVER THE
CENTRAL MOUNTAINS.

ALTHOUGH HEIGHTS ARE ON THE HIGH SIDE THE RIDGE WAS CENTERED WELL TO
THE SOUTHEAST OF PHOENIX...ROUGHLY ALONG THE AZ/NM BORDER AND NEAR
THE MEXICAN BORDER. THIS HAS PLACED A SOUTHWESTERLY FLOW ALOFT
ACROSS MOST OF THE STATE AND THIS IS AN UNFAVORABLE DIRECTION TO
BRING STORMS TO THE LOWER AZ DESERTS. OPERATIONAL MODELS AS WELL AS
ENSEMBLE GUIDANCE CONTINUES TO ADVERTISE A MOSTLY SOUTHWESTERLY
STEERING FLOW ACROSS OUR AREA FOR THE NEXT WEEK AS TROFFING ALOFT
SETS UP ALONG THE WEST COAST. THIS WILL CAUSE MOISTURE TO GRADUALLY
THIN OVER THE WESTERN DESERTS AND WILL LEAD TO LOW GRADE MONSOON
CONDITIONS WHERE STORMS WILL BE PRIMARILY CONFINED TO HIGHER TERRAIN
AREAS TO THE EAST OF PHOENIX. OPERATIONAL MODEL RUNS DO NOT
ADVERTISE ANY SIGNIFICANT INVERTED TROFS OR DISTURBANCES TO ROTATE
AROUND THE HIGH...OR TO MOVE THROUGH THE SOUTHWEST FLOW ALOFT...OVER
THE NEXT SEVERAL DAYS AT LEAST...AND WITHOUT ANY SIGNIFICANT FORCING
FEATURE TO CAUSE AN UPRAMP IN STORM CHANCES...THERE IS LITTLE REASON
TO FORECAST MUCH OUTSIDE OF LOW GRADE MONSOON CONDITIONS...OR CLIMO
TYPE POPS FOR THE 7 DAY FORECAST PERIOD.

FOR THE FIRST COUPLE OF DAYS...TODAY INTO FRIDAY...WITH H5 HEIGHTS
STAYING RATHER HIGH AND MOISTURE THINNING WE WILL BE LOOKING AT
HIGH TEMPERATURES WELL ABOVE SEASONAL NORMALS WITH THE HOTTER
WESTERN DESERTS REACHING OR EXCEEDING 110 DEGREES AND THE GREATER
PHOENIX AREA PUSHING 110. OVER THE WEEKEND AND INTO THE FIRST PART
OF NEXT WEEK AS TROFFING SETS UP ALONG THE WEST COAST AND HEIGHTS
FALL OFF...TEMPS WILL COOL STEADILY. BY EARLY NEXT WEEK HIGHS OVER
THE CENTRAL DESERTS WILL DROP TO LEVELS ONLY SLIGHTLY ABOVE SEASONAL
NORMALS WITH PHOENIX REACHING AROUND 104 BY NEXT MONDAY OR TUESDAY.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

MAINLY FEW-SCT MID-HIGH LEVEL CLOUDS AND LIGHT WINDS 10KT OR LESS
EXPECTED AT ALL TAF SITES. SKIES BECOME SCT-BKN AOA 10KFT ACROSS
SOUTH-CENTRAL AZ...AND THUNDERSTORM ACTIVITY WILL PICK UP AFTER 18Z
OVER THE MOUNTAINS AND HIGHER TERRAIN WELL EAST/NORTH OF PHOENIX...
WITH SKIES REMAINING MOSTLY CLEAR ACROSS SOUTHEAST CALIFORNIA.
POSSIBLE FOR AN ISOLATED STORM TO FORM OVER THE LOWER CENTRAL
DESERTS AND GUSTY OUTFLOWS TO IMPACT KPHX/KIWA/KSDL LATER THIS
AFTERNOON AND EVENING...BUT SOUTHWESTERLY STEERING FLOWS SHOULD KEEP
BULK OF STORMS AWAY FROM TAF SITES.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...

SATURDAY THROUGH WEDNESDAY...DRIER AND WARMER WEATHER WILL SPREAD
INTO REGION FROM THE WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND
EVENING TSTMS IS STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA
COUNTY EACH DAY. HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE
NORMAL WITH HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK
TOWARD NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL
INTO THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY
MOSTLY ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH
VALUES REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...CB
AVIATION...MEYERS
FIRE WEATHER...VASQUEZ/CB





000
FXUS65 KPSR 271000
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
300 AM MST THU AUG 27 2015

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD TODAY. STARTING
FRIDAY THE DRIER AIR WILL PUSH FURTHER EAST CONFINING RAIN CHANCES
TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH THE
WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION... UPPER HIGH REMAINED FIRMLY ENTRENCHED OVER THE WEST-
CENTRAL CONUS THIS MORNING...WITH RELATIVELY HIGH H5 VALUES AROUND
594DM OVER MUCH OF ARIZONA PER THE LATEST 00Z PLOT DATA. IR IMAGERY
AT 2 AM SHOWED DISSIPATING MID LEVEL DEBRIS CLOUD ACROSS SRN AZ WITH
SKIES PARTLY CLOUDY TO MOSTLY CLEAR OVER THE SRN DESERT. SURFACE
DEWPOINTS OVER THE DESERTS WERE A BIT ON THE HIGH SIDE...RANGING
FROM THE UPPER 50S TO MID 60S AT 2 AM. ALSO...LATEST RADAR SHOWED A
FEW NEW STORMS POPPING UP NORTH OF THE GREATER PHOENIX AREA...OVER
THE CENTRAL MOUNTAINS.

ALTHOUGH HEIGHTS ARE ON THE HIGH SIDE THE RIDGE WAS CENTERED WELL TO
THE SOUTHEAST OF PHOENIX...ROUGHLY ALONG THE AZ/NM BORDER AND NEAR
THE MEXICAN BORDER. THIS HAS PLACED A SOUTHWESTERLY FLOW ALOFT
ACROSS MOST OF THE STATE AND THIS IS AN UNFAVORABLE DIRECTION TO
BRING STORMS TO THE LOWER AZ DESERTS. OPERATIONAL MODELS AS WELL AS
ENSEMBLE GUIDANCE CONTINUES TO ADVERTISE A MOSTLY SOUTHWESTERLY
STEERING FLOW ACROSS OUR AREA FOR THE NEXT WEEK AS TROFFING ALOFT
SETS UP ALONG THE WEST COAST. THIS WILL CAUSE MOISTURE TO GRADUALLY
THIN OVER THE WESTERN DESERTS AND WILL LEAD TO LOW GRADE MONSOON
CONDITIONS WHERE STORMS WILL BE PRIMARILY CONFINED TO HIGHER TERRAIN
AREAS TO THE EAST OF PHOENIX. OPERATIONAL MODEL RUNS DO NOT
ADVERTISE ANY SIGNIFICANT INVERTED TROFS OR DISTURBANCES TO ROTATE
AROUND THE HIGH...OR TO MOVE THROUGH THE SOUTHWEST FLOW ALOFT...OVER
THE NEXT SEVERAL DAYS AT LEAST...AND WITHOUT ANY SIGNIFICANT FORCING
FEATURE TO CAUSE AN UPRAMP IN STORM CHANCES...THERE IS LITTLE REASON
TO FORECAST MUCH OUTSIDE OF LOW GRADE MONSOON CONDITIONS...OR CLIMO
TYPE POPS FOR THE 7 DAY FORECAST PERIOD.

FOR THE FIRST COUPLE OF DAYS...TODAY INTO FRIDAY...WITH H5 HEIGHTS
STAYING RATHER HIGH AND MOISTURE THINNING WE WILL BE LOOKING AT
HIGH TEMPERATURES WELL ABOVE SEASONAL NORMALS WITH THE HOTTER
WESTERN DESERTS REACHING OR EXCEEDING 110 DEGREES AND THE GREATER
PHOENIX AREA PUSHING 110. OVER THE WEEKEND AND INTO THE FIRST PART
OF NEXT WEEK AS TROFFING SETS UP ALONG THE WEST COAST AND HEIGHTS
FALL OFF...TEMPS WILL COOL STEADILY. BY EARLY NEXT WEEK HIGHS OVER
THE CENTRAL DESERTS WILL DROP TO LEVELS ONLY SLIGHTLY ABOVE SEASONAL
NORMALS WITH PHOENIX REACHING AROUND 104 BY NEXT MONDAY OR TUESDAY.

&&

.AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND
KSDL...

CURRENT BREEZY SOUTHEASTERLY WINDS AT THE PHX AREA TERMINALS...THAT
ARE BEING GENERATED BY OUTFLOW FROM THUNDERSTORMS THAT DEVELOPED
OVER SE AZ EARLIER THIS EVENING TO GRADUALLY DIMINISH OVER THE NEXT
HOUR OR SO...BUT STILL REMAIN OUT OF AN SOUTHEASTERLY DIRECTION
THROUGH THE REST OF THE NIGHT AND INTO THURSDAY MORNING. WINDS WILL
THEN SHIFT TO TYPICAL WESTERLY DIRECTION ON THURSDAY AFTERNOON. SCT-
BKN MID-HIGH CLOUD LAYERS TO PREVAIL THROUGH THE TAF PERIOD...WITH
ANY THUNDERSTORM ACTIVITY ON THU AFTERNOON/EVENING TO REMAIN WELL
EAST OF THE TAF SITES.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

CURRENT SCT-BKN MID-HIGH LEVEL CIGS TO BECOME CLR-FEW BY THURSDAY
AFTERNOON AS DRIER AIR BEGINS TO FILTER INTO THE REGION FROM THE
WEST. WINDS TO REMAIN MAINLY ON THE LIGHT SIDE...8 KTS OR LESS...AND
FOLLOW TYPICAL DIURNAL TRENDS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER... SATURDAY THROUGH WEDNESDAY... DRIER AND WARMER
WEATHER WILL SPREAD INTO REGION FROM THE WEST...HOWEVER A SLIGHT
CHANCE OF AFTERNOON AND EVENING TSTMS IS STILL FORECAST FOR THE
MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY. HIGH TEMPERATURES
THROUGH SUNDAY WILL BE WELL ABOVE NORMAL WITH HOTTER DESERTS IN
EXCESS OF 110...WITH SOME COOLING BACK TOWARD NORMAL EARLY NEXT
WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL INTO THE 10 TO 15
PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY ABOVE 15
PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES REACHING
25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST WINDS WILL
RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...CB
AVIATION...PERCHA
FIRE WEATHER...VASQUEZ/CB





000
FXUS65 KPSR 270530
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
1030 PM MST WED AUG 26 2015

.UPDATE...AVIATION DISCUSSION.

&&

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD THROUGH THURSDAY.
STARTING FRIDAY THE DRIER AIR WILL PUSH FURTHER EAST CONFINING RAIN
CHANCES TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH
THE WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION... ALTHOUGH THE OVERALL CONVECTIVE ACTIVITY TODAY/THIS
EVENING HAS BEEN LESS THEN YESTERDAY ACROSS OUR CWA...AS
SOUTHWESTERLY FLOW ALOFT BEGINS TO GRADUALLY REDUCE THE AVAILABLE
MOISTURE ACROSS THE REGION...A FEW AREAS DID STILL SEE THUNDERSTORM
ACTIVITY. THE STRONGEST STORMS WERE OVER JOSHUA TREE NATIONAL PARK
THIS AFTERNOON...AS A COMBINATION OF A RICH MOISTURE PLUME THAT
SURGED INTO THE REGION THIS MORNING AND A WEAK SHORTWAVE THAT MOVED
OVER THE REGION HELPED TO TRIGGER STORMS THAT PRODUCED SIGNIFICANT
FLASH FLOODING OVER THE REGION. THE OTHER AREAS THAT SAW STORMS WERE
OVER SOUTHERN GILA COUNTY...WITH THE PINAL PEAK GAUGE REPORTING 2.74
INCH AND A COUPLE OF LOCATIONS IN THE GLOBE AREA SEEING OVER ONE
INCH...AND OVER THE MORE REMOTE AREAS OF LA PAZ AND NORTHERN YUMA
COUNTIES. GIVEN THE LATEST RADAR TRENDS AND HIGH-RES MODELS...IT
APPEARS THAT REST OF THE EVENING WILL BE QUIET...OTHER THEN SOME
LOCALLY GUSTY SOUTHEASTERLY BREEZES OVER THE NEXT COUPLE OF HOURS AS
A OUTFLOW BOUNDARY FROM STORMS OVER PIMA COUNTY MOVE NORTHWESTWARD
ACROSS SOUTH-CENTRAL AZ. AS FAR AS THE SHORT-TERM FORECAST FOR THE
REMAINDER OF TONIGHT...HAVE REDUCED POPS AND MADE SOME MINOR
ADJUSTMENTS TO THE HOURLY GRIDS.

&&

.PREVIOUS DISCUSSION... THE LACK OF LATE MORNING AND EARLY AFTERNOON
CLOUD COVER HAS ALLOWED FOR GOOD SOLAR HEATING AND MUCH OF THE AREA
DESTABILIZING. MOIST BOUNDARY LAYER CONDITIONS REMAIN IN PLACE WITH
SURFACE DEW POINTS IN THE LOWER 60S...BUT SOUTHWESTERLY WINDS ALOFT
HAVE BROUGHT IN DRYING CONDITIONS. AN UPPER LEVEL SHORTWAVE TROUGH
THAT MOVED THROUGH THE LOWER COLORADO RIVER VALLEY EARLY THIS
MORNING HAS QUICKLY PUSHED NORTHEASTWARD INTO NORTHWEST ARIZONA AND
SOUTHERN UTAH. WEAK CONFLUENT FLOW BEHIND THE SHORTWAVE TROUGH WILL
ACROSS AREAS FROM PHOENIX WESTWARD TO THE COLORADO RIVER. STORM
ACTIVITY ACROSS OUR AREA SO FAR TODAY HAS BEEN SLOW TO START...BUT
WE ARE STARTING TO SEE A FEW ISOLATED CELLS OVER THE HIGHEST PEAKS.
THOUGH PLENTY OF MOISTURE IS PRESENT...FEEL ACTIVITY TODAY WILL
REMAIN FAIRLY ISOLATED AND MAINLY CONFINED TO HIGHER TERRAIN AREAS.
THE LACK OF ANY TRIGGER AND WEAK CONFLUENT ANTICYCLONIC FLOW ALOFT
WILL INHIBIT ANY WIDESPREAD STORM ACTIVITY TODAY.

THE UPPER HIGH CENTER WILL SHIFT EVEN FURTHER SOUTH INTO MEXICO ON
THURSDAY KEEPING OUR FLOW ALOFT OUT OF THE SOUTHWEST. GRADUAL DRYING
WILL CONTINUE UNDER THIS REGIME...ESPECIALLY WEST OF PHOENIX...BUT
MOISTURE LEVELS ACROSS THE EASTERN HALF OF ARIZONA WILL ONLY DIP
SLIGHTLY. FLOW ALOFT WILL BE LESS UNFAVORABLE DURING THE DAYTIME
HOURS THURSDAY...BUT ALSO WEAKER COMPARED TO TODAY. THIS MAY LEAD TO
A BIT MORE ACTIVITY OVER SOUTH-CENTRAL ARIZONA ON THURSDAY...BUT
WEAKER STEERING FLOW WILL LIKELY KEEP MUCH OF THE STORM ACTIVITY
OVER HIGHER TERRAIN AREAS AS STORMS SHOULD HAVE A DIFFICULT TIME
MIGRATING INTO THE LOWER ELEVATIONS. A BOOST IN TEMPERATURES IS
EXPECTED AS HEIGHTS ALOFT INCREASE SOMEWHAT AND SURFACE DEW POINTS
LOWER A FEW DEGREES. HIGHS ACROSS THE SOUTHEAST CALIFORNIA AND
SOUTHWEST ARIZONA DESERTS SHOULD REACH NEAR 110 DEGREES.

FRIDAY AND SATURDAY...
THE CENTER OF THE UPPER LEVEL ANTICYCLONE WILL POSITION TO OUR
SOUTH..AND ATMOSPHERIC MOISTURE WILL CONTINUE TO THIN OUT...WITH
FORECASTED PRECIPITABLE WATER POTENTIALLY DROPPING TO JUST ABOVE ONE
INCH. THE DRIER AIRMASS WILL SUPPORT WARMER TEMPERATURES FOR THE
LOWER DESERTS...WITH DAYTIME HIGHS FOR YUMA...EL CENTRO AND GILA
BEND AGAIN HITTING THE 110-112 DEGREE RANGE FRIDAY AND SATURDAY.
HOWEVER...THE UPPER LEVEL HIGH STARTS TO REBOUND OVER THE WEEKEND...
592DM 500MB HEIGHTS CENTERING ALONG THE AZ/NM BORDER...SO SOME
MOISTURE RETURN TO THE DESERT SOUTHWEST IS POSSIBLE. THIS MIGHT
OFFSET THE PROJECTED HOT TEMPERATURE FORECAST FOR THESE DAYS BY A
FEW DEGREES. OVER THE LAST NORMAL PERIOD 1981-2010...THE AVERAGE
LAST 110F DAY IN PHOENIX FALLS ON AUGUST 26TH...AND SEPTEMBER 6TH
FOR YUMA. WE COULD POTENTIALLY PUSH PAST THE AVERAGE LAST DAY IN THE
PHOENIX AREA BY THE END OF THE WEEKEND.

SUNDAY INTO TUESDAY...
A STRONG EASTERN PACIFIC UPPER LEVEL TROUGH APPROACHES THE PACIFIC
NORTHWEST AND NORTHERN CALIFORNIA COAST. STARTING LATE IN THE
WEEKEND...THE TROUGH BEGINS TO ENCROACH ON AND BREAK DOWN THE RIDGE
PATTERN OVER THE INTERMOUNTAIN WEST. WITH THE TREND FOR LOWER HEIGHTS
NOTED IN THE MODELS/ENSEMBLE SOLUTIONS... TEMPERATURES IN THE
EXTENDED WERE SUBTLY COOLED SUNDAY INTO EARLY NEXT WEEK WITH MOSTLY
BELOW NORMAL POPS ACROSS THE REGION.

&&

.AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND
KSDL...

CURRENT BREEZY SOUTHEASTERLY WINDS AT THE PHX AREA TERMINALS...THAT
ARE BEING GENERATED BY OUTFLOW FROM THUNDERSTORMS THAT DEVELOPED
OVER SE AZ EARLIER THIS EVENING TO GRADUALLY DIMINISH OVER THE NEXT
HOUR OR SO...BUT STILL REMAIN OUT OF AN SOUTHEASTERLY DIRECTION
THROUGH THE REST OF THE NIGHT AND INTO THURSDAY MORNING. WINDS WILL
THEN SHIFT TO TYPICAL WESTERLY DIRECTION ON THURSDAY AFTERNOON. SCT-
BKN MID-HIGH CLOUD LAYERS TO PREVAIL THROUGH THE TAF PERIOD...WITH
ANY THUNDERSTORM ACTIVITY ON THU AFTERNOON/EVENING TO REMAIN WELL
EAST OF THE TAF SITES.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

CURRENT SCT-BKN MID-HIGH LEVEL CIGS TO BECOME CLR-FEW BY THURSDAY
AFTERNOON AS DRIER AIR BEGINS TO FILTER INTO THE REGION FROM THE
WEST. WINDS TO REMAIN MAINLY ON THE LIGHT SIDE...8 KTS OR LESS...AND
FOLLOW TYPICAL DIURNAL TRENDS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER... SATURDAY THROUGH WEDNESDAY... DRIER AND WARMER
WEATHER WILL SPREAD INTO REGION FROM THE WEST...HOWEVER A SLIGHT
CHANCE OF AFTERNOON AND EVENING TSTMS IS STILL FORECAST FOR THE
MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY. HIGH TEMPERATURES
THROUGH SUNDAY WILL BE WELL ABOVE NORMAL WITH HOTTER DESERTS IN
EXCESS OF 110...WITH SOME COOLING BACK TOWARD NORMAL EARLY NEXT
WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL INTO THE 10 TO 15
PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY ABOVE 15
PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES REACHING
25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST WINDS WILL
RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...PERCHA
AVIATION...PERCHA
FIRE WEATHER...VASQUEZ/CB





000
FXUS65 KPSR 270530
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
1030 PM MST WED AUG 26 2015

.UPDATE...AVIATION DISCUSSION.

&&

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD THROUGH THURSDAY.
STARTING FRIDAY THE DRIER AIR WILL PUSH FURTHER EAST CONFINING RAIN
CHANCES TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH
THE WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION... ALTHOUGH THE OVERALL CONVECTIVE ACTIVITY TODAY/THIS
EVENING HAS BEEN LESS THEN YESTERDAY ACROSS OUR CWA...AS
SOUTHWESTERLY FLOW ALOFT BEGINS TO GRADUALLY REDUCE THE AVAILABLE
MOISTURE ACROSS THE REGION...A FEW AREAS DID STILL SEE THUNDERSTORM
ACTIVITY. THE STRONGEST STORMS WERE OVER JOSHUA TREE NATIONAL PARK
THIS AFTERNOON...AS A COMBINATION OF A RICH MOISTURE PLUME THAT
SURGED INTO THE REGION THIS MORNING AND A WEAK SHORTWAVE THAT MOVED
OVER THE REGION HELPED TO TRIGGER STORMS THAT PRODUCED SIGNIFICANT
FLASH FLOODING OVER THE REGION. THE OTHER AREAS THAT SAW STORMS WERE
OVER SOUTHERN GILA COUNTY...WITH THE PINAL PEAK GAUGE REPORTING 2.74
INCH AND A COUPLE OF LOCATIONS IN THE GLOBE AREA SEEING OVER ONE
INCH...AND OVER THE MORE REMOTE AREAS OF LA PAZ AND NORTHERN YUMA
COUNTIES. GIVEN THE LATEST RADAR TRENDS AND HIGH-RES MODELS...IT
APPEARS THAT REST OF THE EVENING WILL BE QUIET...OTHER THEN SOME
LOCALLY GUSTY SOUTHEASTERLY BREEZES OVER THE NEXT COUPLE OF HOURS AS
A OUTFLOW BOUNDARY FROM STORMS OVER PIMA COUNTY MOVE NORTHWESTWARD
ACROSS SOUTH-CENTRAL AZ. AS FAR AS THE SHORT-TERM FORECAST FOR THE
REMAINDER OF TONIGHT...HAVE REDUCED POPS AND MADE SOME MINOR
ADJUSTMENTS TO THE HOURLY GRIDS.

&&

.PREVIOUS DISCUSSION... THE LACK OF LATE MORNING AND EARLY AFTERNOON
CLOUD COVER HAS ALLOWED FOR GOOD SOLAR HEATING AND MUCH OF THE AREA
DESTABILIZING. MOIST BOUNDARY LAYER CONDITIONS REMAIN IN PLACE WITH
SURFACE DEW POINTS IN THE LOWER 60S...BUT SOUTHWESTERLY WINDS ALOFT
HAVE BROUGHT IN DRYING CONDITIONS. AN UPPER LEVEL SHORTWAVE TROUGH
THAT MOVED THROUGH THE LOWER COLORADO RIVER VALLEY EARLY THIS
MORNING HAS QUICKLY PUSHED NORTHEASTWARD INTO NORTHWEST ARIZONA AND
SOUTHERN UTAH. WEAK CONFLUENT FLOW BEHIND THE SHORTWAVE TROUGH WILL
ACROSS AREAS FROM PHOENIX WESTWARD TO THE COLORADO RIVER. STORM
ACTIVITY ACROSS OUR AREA SO FAR TODAY HAS BEEN SLOW TO START...BUT
WE ARE STARTING TO SEE A FEW ISOLATED CELLS OVER THE HIGHEST PEAKS.
THOUGH PLENTY OF MOISTURE IS PRESENT...FEEL ACTIVITY TODAY WILL
REMAIN FAIRLY ISOLATED AND MAINLY CONFINED TO HIGHER TERRAIN AREAS.
THE LACK OF ANY TRIGGER AND WEAK CONFLUENT ANTICYCLONIC FLOW ALOFT
WILL INHIBIT ANY WIDESPREAD STORM ACTIVITY TODAY.

THE UPPER HIGH CENTER WILL SHIFT EVEN FURTHER SOUTH INTO MEXICO ON
THURSDAY KEEPING OUR FLOW ALOFT OUT OF THE SOUTHWEST. GRADUAL DRYING
WILL CONTINUE UNDER THIS REGIME...ESPECIALLY WEST OF PHOENIX...BUT
MOISTURE LEVELS ACROSS THE EASTERN HALF OF ARIZONA WILL ONLY DIP
SLIGHTLY. FLOW ALOFT WILL BE LESS UNFAVORABLE DURING THE DAYTIME
HOURS THURSDAY...BUT ALSO WEAKER COMPARED TO TODAY. THIS MAY LEAD TO
A BIT MORE ACTIVITY OVER SOUTH-CENTRAL ARIZONA ON THURSDAY...BUT
WEAKER STEERING FLOW WILL LIKELY KEEP MUCH OF THE STORM ACTIVITY
OVER HIGHER TERRAIN AREAS AS STORMS SHOULD HAVE A DIFFICULT TIME
MIGRATING INTO THE LOWER ELEVATIONS. A BOOST IN TEMPERATURES IS
EXPECTED AS HEIGHTS ALOFT INCREASE SOMEWHAT AND SURFACE DEW POINTS
LOWER A FEW DEGREES. HIGHS ACROSS THE SOUTHEAST CALIFORNIA AND
SOUTHWEST ARIZONA DESERTS SHOULD REACH NEAR 110 DEGREES.

FRIDAY AND SATURDAY...
THE CENTER OF THE UPPER LEVEL ANTICYCLONE WILL POSITION TO OUR
SOUTH..AND ATMOSPHERIC MOISTURE WILL CONTINUE TO THIN OUT...WITH
FORECASTED PRECIPITABLE WATER POTENTIALLY DROPPING TO JUST ABOVE ONE
INCH. THE DRIER AIRMASS WILL SUPPORT WARMER TEMPERATURES FOR THE
LOWER DESERTS...WITH DAYTIME HIGHS FOR YUMA...EL CENTRO AND GILA
BEND AGAIN HITTING THE 110-112 DEGREE RANGE FRIDAY AND SATURDAY.
HOWEVER...THE UPPER LEVEL HIGH STARTS TO REBOUND OVER THE WEEKEND...
592DM 500MB HEIGHTS CENTERING ALONG THE AZ/NM BORDER...SO SOME
MOISTURE RETURN TO THE DESERT SOUTHWEST IS POSSIBLE. THIS MIGHT
OFFSET THE PROJECTED HOT TEMPERATURE FORECAST FOR THESE DAYS BY A
FEW DEGREES. OVER THE LAST NORMAL PERIOD 1981-2010...THE AVERAGE
LAST 110F DAY IN PHOENIX FALLS ON AUGUST 26TH...AND SEPTEMBER 6TH
FOR YUMA. WE COULD POTENTIALLY PUSH PAST THE AVERAGE LAST DAY IN THE
PHOENIX AREA BY THE END OF THE WEEKEND.

SUNDAY INTO TUESDAY...
A STRONG EASTERN PACIFIC UPPER LEVEL TROUGH APPROACHES THE PACIFIC
NORTHWEST AND NORTHERN CALIFORNIA COAST. STARTING LATE IN THE
WEEKEND...THE TROUGH BEGINS TO ENCROACH ON AND BREAK DOWN THE RIDGE
PATTERN OVER THE INTERMOUNTAIN WEST. WITH THE TREND FOR LOWER HEIGHTS
NOTED IN THE MODELS/ENSEMBLE SOLUTIONS... TEMPERATURES IN THE
EXTENDED WERE SUBTLY COOLED SUNDAY INTO EARLY NEXT WEEK WITH MOSTLY
BELOW NORMAL POPS ACROSS THE REGION.

&&

.AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND
KSDL...

CURRENT BREEZY SOUTHEASTERLY WINDS AT THE PHX AREA TERMINALS...THAT
ARE BEING GENERATED BY OUTFLOW FROM THUNDERSTORMS THAT DEVELOPED
OVER SE AZ EARLIER THIS EVENING TO GRADUALLY DIMINISH OVER THE NEXT
HOUR OR SO...BUT STILL REMAIN OUT OF AN SOUTHEASTERLY DIRECTION
THROUGH THE REST OF THE NIGHT AND INTO THURSDAY MORNING. WINDS WILL
THEN SHIFT TO TYPICAL WESTERLY DIRECTION ON THURSDAY AFTERNOON. SCT-
BKN MID-HIGH CLOUD LAYERS TO PREVAIL THROUGH THE TAF PERIOD...WITH
ANY THUNDERSTORM ACTIVITY ON THU AFTERNOON/EVENING TO REMAIN WELL
EAST OF THE TAF SITES.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

CURRENT SCT-BKN MID-HIGH LEVEL CIGS TO BECOME CLR-FEW BY THURSDAY
AFTERNOON AS DRIER AIR BEGINS TO FILTER INTO THE REGION FROM THE
WEST. WINDS TO REMAIN MAINLY ON THE LIGHT SIDE...8 KTS OR LESS...AND
FOLLOW TYPICAL DIURNAL TRENDS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER... SATURDAY THROUGH WEDNESDAY... DRIER AND WARMER
WEATHER WILL SPREAD INTO REGION FROM THE WEST...HOWEVER A SLIGHT
CHANCE OF AFTERNOON AND EVENING TSTMS IS STILL FORECAST FOR THE
MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY. HIGH TEMPERATURES
THROUGH SUNDAY WILL BE WELL ABOVE NORMAL WITH HOTTER DESERTS IN
EXCESS OF 110...WITH SOME COOLING BACK TOWARD NORMAL EARLY NEXT
WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL INTO THE 10 TO 15
PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY ABOVE 15
PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES REACHING
25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST WINDS WILL
RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...PERCHA
AVIATION...PERCHA
FIRE WEATHER...VASQUEZ/CB





000
FXUS65 KPSR 270530
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
1030 PM MST WED AUG 26 2015

.UPDATE...AVIATION DISCUSSION.

&&

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD THROUGH THURSDAY.
STARTING FRIDAY THE DRIER AIR WILL PUSH FURTHER EAST CONFINING RAIN
CHANCES TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH
THE WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION... ALTHOUGH THE OVERALL CONVECTIVE ACTIVITY TODAY/THIS
EVENING HAS BEEN LESS THEN YESTERDAY ACROSS OUR CWA...AS
SOUTHWESTERLY FLOW ALOFT BEGINS TO GRADUALLY REDUCE THE AVAILABLE
MOISTURE ACROSS THE REGION...A FEW AREAS DID STILL SEE THUNDERSTORM
ACTIVITY. THE STRONGEST STORMS WERE OVER JOSHUA TREE NATIONAL PARK
THIS AFTERNOON...AS A COMBINATION OF A RICH MOISTURE PLUME THAT
SURGED INTO THE REGION THIS MORNING AND A WEAK SHORTWAVE THAT MOVED
OVER THE REGION HELPED TO TRIGGER STORMS THAT PRODUCED SIGNIFICANT
FLASH FLOODING OVER THE REGION. THE OTHER AREAS THAT SAW STORMS WERE
OVER SOUTHERN GILA COUNTY...WITH THE PINAL PEAK GAUGE REPORTING 2.74
INCH AND A COUPLE OF LOCATIONS IN THE GLOBE AREA SEEING OVER ONE
INCH...AND OVER THE MORE REMOTE AREAS OF LA PAZ AND NORTHERN YUMA
COUNTIES. GIVEN THE LATEST RADAR TRENDS AND HIGH-RES MODELS...IT
APPEARS THAT REST OF THE EVENING WILL BE QUIET...OTHER THEN SOME
LOCALLY GUSTY SOUTHEASTERLY BREEZES OVER THE NEXT COUPLE OF HOURS AS
A OUTFLOW BOUNDARY FROM STORMS OVER PIMA COUNTY MOVE NORTHWESTWARD
ACROSS SOUTH-CENTRAL AZ. AS FAR AS THE SHORT-TERM FORECAST FOR THE
REMAINDER OF TONIGHT...HAVE REDUCED POPS AND MADE SOME MINOR
ADJUSTMENTS TO THE HOURLY GRIDS.

&&

.PREVIOUS DISCUSSION... THE LACK OF LATE MORNING AND EARLY AFTERNOON
CLOUD COVER HAS ALLOWED FOR GOOD SOLAR HEATING AND MUCH OF THE AREA
DESTABILIZING. MOIST BOUNDARY LAYER CONDITIONS REMAIN IN PLACE WITH
SURFACE DEW POINTS IN THE LOWER 60S...BUT SOUTHWESTERLY WINDS ALOFT
HAVE BROUGHT IN DRYING CONDITIONS. AN UPPER LEVEL SHORTWAVE TROUGH
THAT MOVED THROUGH THE LOWER COLORADO RIVER VALLEY EARLY THIS
MORNING HAS QUICKLY PUSHED NORTHEASTWARD INTO NORTHWEST ARIZONA AND
SOUTHERN UTAH. WEAK CONFLUENT FLOW BEHIND THE SHORTWAVE TROUGH WILL
ACROSS AREAS FROM PHOENIX WESTWARD TO THE COLORADO RIVER. STORM
ACTIVITY ACROSS OUR AREA SO FAR TODAY HAS BEEN SLOW TO START...BUT
WE ARE STARTING TO SEE A FEW ISOLATED CELLS OVER THE HIGHEST PEAKS.
THOUGH PLENTY OF MOISTURE IS PRESENT...FEEL ACTIVITY TODAY WILL
REMAIN FAIRLY ISOLATED AND MAINLY CONFINED TO HIGHER TERRAIN AREAS.
THE LACK OF ANY TRIGGER AND WEAK CONFLUENT ANTICYCLONIC FLOW ALOFT
WILL INHIBIT ANY WIDESPREAD STORM ACTIVITY TODAY.

THE UPPER HIGH CENTER WILL SHIFT EVEN FURTHER SOUTH INTO MEXICO ON
THURSDAY KEEPING OUR FLOW ALOFT OUT OF THE SOUTHWEST. GRADUAL DRYING
WILL CONTINUE UNDER THIS REGIME...ESPECIALLY WEST OF PHOENIX...BUT
MOISTURE LEVELS ACROSS THE EASTERN HALF OF ARIZONA WILL ONLY DIP
SLIGHTLY. FLOW ALOFT WILL BE LESS UNFAVORABLE DURING THE DAYTIME
HOURS THURSDAY...BUT ALSO WEAKER COMPARED TO TODAY. THIS MAY LEAD TO
A BIT MORE ACTIVITY OVER SOUTH-CENTRAL ARIZONA ON THURSDAY...BUT
WEAKER STEERING FLOW WILL LIKELY KEEP MUCH OF THE STORM ACTIVITY
OVER HIGHER TERRAIN AREAS AS STORMS SHOULD HAVE A DIFFICULT TIME
MIGRATING INTO THE LOWER ELEVATIONS. A BOOST IN TEMPERATURES IS
EXPECTED AS HEIGHTS ALOFT INCREASE SOMEWHAT AND SURFACE DEW POINTS
LOWER A FEW DEGREES. HIGHS ACROSS THE SOUTHEAST CALIFORNIA AND
SOUTHWEST ARIZONA DESERTS SHOULD REACH NEAR 110 DEGREES.

FRIDAY AND SATURDAY...
THE CENTER OF THE UPPER LEVEL ANTICYCLONE WILL POSITION TO OUR
SOUTH..AND ATMOSPHERIC MOISTURE WILL CONTINUE TO THIN OUT...WITH
FORECASTED PRECIPITABLE WATER POTENTIALLY DROPPING TO JUST ABOVE ONE
INCH. THE DRIER AIRMASS WILL SUPPORT WARMER TEMPERATURES FOR THE
LOWER DESERTS...WITH DAYTIME HIGHS FOR YUMA...EL CENTRO AND GILA
BEND AGAIN HITTING THE 110-112 DEGREE RANGE FRIDAY AND SATURDAY.
HOWEVER...THE UPPER LEVEL HIGH STARTS TO REBOUND OVER THE WEEKEND...
592DM 500MB HEIGHTS CENTERING ALONG THE AZ/NM BORDER...SO SOME
MOISTURE RETURN TO THE DESERT SOUTHWEST IS POSSIBLE. THIS MIGHT
OFFSET THE PROJECTED HOT TEMPERATURE FORECAST FOR THESE DAYS BY A
FEW DEGREES. OVER THE LAST NORMAL PERIOD 1981-2010...THE AVERAGE
LAST 110F DAY IN PHOENIX FALLS ON AUGUST 26TH...AND SEPTEMBER 6TH
FOR YUMA. WE COULD POTENTIALLY PUSH PAST THE AVERAGE LAST DAY IN THE
PHOENIX AREA BY THE END OF THE WEEKEND.

SUNDAY INTO TUESDAY...
A STRONG EASTERN PACIFIC UPPER LEVEL TROUGH APPROACHES THE PACIFIC
NORTHWEST AND NORTHERN CALIFORNIA COAST. STARTING LATE IN THE
WEEKEND...THE TROUGH BEGINS TO ENCROACH ON AND BREAK DOWN THE RIDGE
PATTERN OVER THE INTERMOUNTAIN WEST. WITH THE TREND FOR LOWER HEIGHTS
NOTED IN THE MODELS/ENSEMBLE SOLUTIONS... TEMPERATURES IN THE
EXTENDED WERE SUBTLY COOLED SUNDAY INTO EARLY NEXT WEEK WITH MOSTLY
BELOW NORMAL POPS ACROSS THE REGION.

&&

.AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND
KSDL...

CURRENT BREEZY SOUTHEASTERLY WINDS AT THE PHX AREA TERMINALS...THAT
ARE BEING GENERATED BY OUTFLOW FROM THUNDERSTORMS THAT DEVELOPED
OVER SE AZ EARLIER THIS EVENING TO GRADUALLY DIMINISH OVER THE NEXT
HOUR OR SO...BUT STILL REMAIN OUT OF AN SOUTHEASTERLY DIRECTION
THROUGH THE REST OF THE NIGHT AND INTO THURSDAY MORNING. WINDS WILL
THEN SHIFT TO TYPICAL WESTERLY DIRECTION ON THURSDAY AFTERNOON. SCT-
BKN MID-HIGH CLOUD LAYERS TO PREVAIL THROUGH THE TAF PERIOD...WITH
ANY THUNDERSTORM ACTIVITY ON THU AFTERNOON/EVENING TO REMAIN WELL
EAST OF THE TAF SITES.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

CURRENT SCT-BKN MID-HIGH LEVEL CIGS TO BECOME CLR-FEW BY THURSDAY
AFTERNOON AS DRIER AIR BEGINS TO FILTER INTO THE REGION FROM THE
WEST. WINDS TO REMAIN MAINLY ON THE LIGHT SIDE...8 KTS OR LESS...AND
FOLLOW TYPICAL DIURNAL TRENDS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER... SATURDAY THROUGH WEDNESDAY... DRIER AND WARMER
WEATHER WILL SPREAD INTO REGION FROM THE WEST...HOWEVER A SLIGHT
CHANCE OF AFTERNOON AND EVENING TSTMS IS STILL FORECAST FOR THE
MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY. HIGH TEMPERATURES
THROUGH SUNDAY WILL BE WELL ABOVE NORMAL WITH HOTTER DESERTS IN
EXCESS OF 110...WITH SOME COOLING BACK TOWARD NORMAL EARLY NEXT
WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL INTO THE 10 TO 15
PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY ABOVE 15
PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES REACHING
25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST WINDS WILL
RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...PERCHA
AVIATION...PERCHA
FIRE WEATHER...VASQUEZ/CB




000
FXUS65 KPSR 270530
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
1030 PM MST WED AUG 26 2015

.UPDATE...AVIATION DISCUSSION.

&&

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD THROUGH THURSDAY.
STARTING FRIDAY THE DRIER AIR WILL PUSH FURTHER EAST CONFINING RAIN
CHANCES TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH
THE WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION... ALTHOUGH THE OVERALL CONVECTIVE ACTIVITY TODAY/THIS
EVENING HAS BEEN LESS THEN YESTERDAY ACROSS OUR CWA...AS
SOUTHWESTERLY FLOW ALOFT BEGINS TO GRADUALLY REDUCE THE AVAILABLE
MOISTURE ACROSS THE REGION...A FEW AREAS DID STILL SEE THUNDERSTORM
ACTIVITY. THE STRONGEST STORMS WERE OVER JOSHUA TREE NATIONAL PARK
THIS AFTERNOON...AS A COMBINATION OF A RICH MOISTURE PLUME THAT
SURGED INTO THE REGION THIS MORNING AND A WEAK SHORTWAVE THAT MOVED
OVER THE REGION HELPED TO TRIGGER STORMS THAT PRODUCED SIGNIFICANT
FLASH FLOODING OVER THE REGION. THE OTHER AREAS THAT SAW STORMS WERE
OVER SOUTHERN GILA COUNTY...WITH THE PINAL PEAK GAUGE REPORTING 2.74
INCH AND A COUPLE OF LOCATIONS IN THE GLOBE AREA SEEING OVER ONE
INCH...AND OVER THE MORE REMOTE AREAS OF LA PAZ AND NORTHERN YUMA
COUNTIES. GIVEN THE LATEST RADAR TRENDS AND HIGH-RES MODELS...IT
APPEARS THAT REST OF THE EVENING WILL BE QUIET...OTHER THEN SOME
LOCALLY GUSTY SOUTHEASTERLY BREEZES OVER THE NEXT COUPLE OF HOURS AS
A OUTFLOW BOUNDARY FROM STORMS OVER PIMA COUNTY MOVE NORTHWESTWARD
ACROSS SOUTH-CENTRAL AZ. AS FAR AS THE SHORT-TERM FORECAST FOR THE
REMAINDER OF TONIGHT...HAVE REDUCED POPS AND MADE SOME MINOR
ADJUSTMENTS TO THE HOURLY GRIDS.

&&

.PREVIOUS DISCUSSION... THE LACK OF LATE MORNING AND EARLY AFTERNOON
CLOUD COVER HAS ALLOWED FOR GOOD SOLAR HEATING AND MUCH OF THE AREA
DESTABILIZING. MOIST BOUNDARY LAYER CONDITIONS REMAIN IN PLACE WITH
SURFACE DEW POINTS IN THE LOWER 60S...BUT SOUTHWESTERLY WINDS ALOFT
HAVE BROUGHT IN DRYING CONDITIONS. AN UPPER LEVEL SHORTWAVE TROUGH
THAT MOVED THROUGH THE LOWER COLORADO RIVER VALLEY EARLY THIS
MORNING HAS QUICKLY PUSHED NORTHEASTWARD INTO NORTHWEST ARIZONA AND
SOUTHERN UTAH. WEAK CONFLUENT FLOW BEHIND THE SHORTWAVE TROUGH WILL
ACROSS AREAS FROM PHOENIX WESTWARD TO THE COLORADO RIVER. STORM
ACTIVITY ACROSS OUR AREA SO FAR TODAY HAS BEEN SLOW TO START...BUT
WE ARE STARTING TO SEE A FEW ISOLATED CELLS OVER THE HIGHEST PEAKS.
THOUGH PLENTY OF MOISTURE IS PRESENT...FEEL ACTIVITY TODAY WILL
REMAIN FAIRLY ISOLATED AND MAINLY CONFINED TO HIGHER TERRAIN AREAS.
THE LACK OF ANY TRIGGER AND WEAK CONFLUENT ANTICYCLONIC FLOW ALOFT
WILL INHIBIT ANY WIDESPREAD STORM ACTIVITY TODAY.

THE UPPER HIGH CENTER WILL SHIFT EVEN FURTHER SOUTH INTO MEXICO ON
THURSDAY KEEPING OUR FLOW ALOFT OUT OF THE SOUTHWEST. GRADUAL DRYING
WILL CONTINUE UNDER THIS REGIME...ESPECIALLY WEST OF PHOENIX...BUT
MOISTURE LEVELS ACROSS THE EASTERN HALF OF ARIZONA WILL ONLY DIP
SLIGHTLY. FLOW ALOFT WILL BE LESS UNFAVORABLE DURING THE DAYTIME
HOURS THURSDAY...BUT ALSO WEAKER COMPARED TO TODAY. THIS MAY LEAD TO
A BIT MORE ACTIVITY OVER SOUTH-CENTRAL ARIZONA ON THURSDAY...BUT
WEAKER STEERING FLOW WILL LIKELY KEEP MUCH OF THE STORM ACTIVITY
OVER HIGHER TERRAIN AREAS AS STORMS SHOULD HAVE A DIFFICULT TIME
MIGRATING INTO THE LOWER ELEVATIONS. A BOOST IN TEMPERATURES IS
EXPECTED AS HEIGHTS ALOFT INCREASE SOMEWHAT AND SURFACE DEW POINTS
LOWER A FEW DEGREES. HIGHS ACROSS THE SOUTHEAST CALIFORNIA AND
SOUTHWEST ARIZONA DESERTS SHOULD REACH NEAR 110 DEGREES.

FRIDAY AND SATURDAY...
THE CENTER OF THE UPPER LEVEL ANTICYCLONE WILL POSITION TO OUR
SOUTH..AND ATMOSPHERIC MOISTURE WILL CONTINUE TO THIN OUT...WITH
FORECASTED PRECIPITABLE WATER POTENTIALLY DROPPING TO JUST ABOVE ONE
INCH. THE DRIER AIRMASS WILL SUPPORT WARMER TEMPERATURES FOR THE
LOWER DESERTS...WITH DAYTIME HIGHS FOR YUMA...EL CENTRO AND GILA
BEND AGAIN HITTING THE 110-112 DEGREE RANGE FRIDAY AND SATURDAY.
HOWEVER...THE UPPER LEVEL HIGH STARTS TO REBOUND OVER THE WEEKEND...
592DM 500MB HEIGHTS CENTERING ALONG THE AZ/NM BORDER...SO SOME
MOISTURE RETURN TO THE DESERT SOUTHWEST IS POSSIBLE. THIS MIGHT
OFFSET THE PROJECTED HOT TEMPERATURE FORECAST FOR THESE DAYS BY A
FEW DEGREES. OVER THE LAST NORMAL PERIOD 1981-2010...THE AVERAGE
LAST 110F DAY IN PHOENIX FALLS ON AUGUST 26TH...AND SEPTEMBER 6TH
FOR YUMA. WE COULD POTENTIALLY PUSH PAST THE AVERAGE LAST DAY IN THE
PHOENIX AREA BY THE END OF THE WEEKEND.

SUNDAY INTO TUESDAY...
A STRONG EASTERN PACIFIC UPPER LEVEL TROUGH APPROACHES THE PACIFIC
NORTHWEST AND NORTHERN CALIFORNIA COAST. STARTING LATE IN THE
WEEKEND...THE TROUGH BEGINS TO ENCROACH ON AND BREAK DOWN THE RIDGE
PATTERN OVER THE INTERMOUNTAIN WEST. WITH THE TREND FOR LOWER HEIGHTS
NOTED IN THE MODELS/ENSEMBLE SOLUTIONS... TEMPERATURES IN THE
EXTENDED WERE SUBTLY COOLED SUNDAY INTO EARLY NEXT WEEK WITH MOSTLY
BELOW NORMAL POPS ACROSS THE REGION.

&&

.AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND
KSDL...

CURRENT BREEZY SOUTHEASTERLY WINDS AT THE PHX AREA TERMINALS...THAT
ARE BEING GENERATED BY OUTFLOW FROM THUNDERSTORMS THAT DEVELOPED
OVER SE AZ EARLIER THIS EVENING TO GRADUALLY DIMINISH OVER THE NEXT
HOUR OR SO...BUT STILL REMAIN OUT OF AN SOUTHEASTERLY DIRECTION
THROUGH THE REST OF THE NIGHT AND INTO THURSDAY MORNING. WINDS WILL
THEN SHIFT TO TYPICAL WESTERLY DIRECTION ON THURSDAY AFTERNOON. SCT-
BKN MID-HIGH CLOUD LAYERS TO PREVAIL THROUGH THE TAF PERIOD...WITH
ANY THUNDERSTORM ACTIVITY ON THU AFTERNOON/EVENING TO REMAIN WELL
EAST OF THE TAF SITES.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

CURRENT SCT-BKN MID-HIGH LEVEL CIGS TO BECOME CLR-FEW BY THURSDAY
AFTERNOON AS DRIER AIR BEGINS TO FILTER INTO THE REGION FROM THE
WEST. WINDS TO REMAIN MAINLY ON THE LIGHT SIDE...8 KTS OR LESS...AND
FOLLOW TYPICAL DIURNAL TRENDS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER... SATURDAY THROUGH WEDNESDAY... DRIER AND WARMER
WEATHER WILL SPREAD INTO REGION FROM THE WEST...HOWEVER A SLIGHT
CHANCE OF AFTERNOON AND EVENING TSTMS IS STILL FORECAST FOR THE
MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY. HIGH TEMPERATURES
THROUGH SUNDAY WILL BE WELL ABOVE NORMAL WITH HOTTER DESERTS IN
EXCESS OF 110...WITH SOME COOLING BACK TOWARD NORMAL EARLY NEXT
WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL INTO THE 10 TO 15
PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY ABOVE 15
PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES REACHING
25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST WINDS WILL
RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...PERCHA
AVIATION...PERCHA
FIRE WEATHER...VASQUEZ/CB




000
FXUS65 KPSR 270410
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
910 PM MST WED AUG 26 2015

&&

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD THROUGH THURSDAY.
STARTING FRIDAY THE DRIER AIR WILL PUSH FURTHER EAST CONFINING RAIN
CHANCES TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH
THE WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION... ALTHOUGH THE OVERALL CONVECTIVE ACTIVITY TODAY/THIS
EVENING HAS BEEN LESS THEN YESTERDAY ACROSS OUR CWA...AS
SOUTHWESTERLY FLOW ALOFT BEGINS TO GRADUALLY REDUCE THE AVAILABLE
MOISTURE ACROSS THE REGION...A FEW AREAS DID STILL SEE THUNDERSTORM
ACTIVITY. THE STRONGEST STORMS WERE OVER JOSHUA TREE NATIONAL PARK
THIS AFTERNOON...AS A COMBINATION OF A RICH MOISTURE PLUME THAT
SURGED INTO THE REGION THIS MORNING AND A WEAK SHORTWAVE THAT MOVED
OVER THE REGION HELPED TO TRIGGER STORMS THAT PRODUCED SIGNIFICANT
FLASH FLOODING OVER THE REGION. THE OTHER AREAS THAT SAW STORMS WERE
OVER SOUTHERN GILA COUNTY...WITH THE PINAL PEAK GAUGE REPORTING 2.74
INCH AND A COUPLE OF LOCATIONS IN THE GLOBE AREA SEEING OVER ONE
INCH...AND OVER THE MORE REMOTE AREAS OF LA PAZ AND NORTHERN YUMA
COUNTIES. GIVEN THE LATEST RADAR TRENDS AND HIGH-RES MODELS...IT
APPEARS THAT REST OF THE EVENING WILL BE QUIET...OTHER THEN SOME
LOCALLY GUSTY SOUTHEASTERLY BREEZES OVER THE NEXT COUPLE OF HOURS AS
A OUTFLOW BOUNDARY FROM STORMS OVER PIMA COUNTY MOVE NORTHWESTWARD
ACROSS SOUTH-CENTRAL AZ. AS FAR AS THE SHORT-TERM FORECAST FOR THE
REMAINDER OF TONIGHT...HAVE REDUCED POPS AND MADE SOME MINOR
ADJUSTMENTS TO THE HOURLY GRIDS.

&&

.PREVIOUS DISCUSSION... THE LACK OF LATE MORNING AND EARLY AFTERNOON
CLOUD COVER HAS ALLOWED FOR GOOD SOLAR HEATING AND MUCH OF THE AREA
DESTABILIZING. MOIST BOUNDARY LAYER CONDITIONS REMAIN IN PLACE WITH
SURFACE DEW POINTS IN THE LOWER 60S...BUT SOUTHWESTERLY WINDS ALOFT
HAVE BROUGHT IN DRYING CONDITIONS. AN UPPER LEVEL SHORTWAVE TROUGH
THAT MOVED THROUGH THE LOWER COLORADO RIVER VALLEY EARLY THIS
MORNING HAS QUICKLY PUSHED NORTHEASTWARD INTO NORTHWEST ARIZONA AND
SOUTHERN UTAH. WEAK CONFLUENT FLOW BEHIND THE SHORTWAVE TROUGH WILL
ACROSS AREAS FROM PHOENIX WESTWARD TO THE COLORADO RIVER. STORM
ACTIVITY ACROSS OUR AREA SO FAR TODAY HAS BEEN SLOW TO START...BUT
WE ARE STARTING TO SEE A FEW ISOLATED CELLS OVER THE HIGHEST PEAKS.
THOUGH PLENTY OF MOISTURE IS PRESENT...FEEL ACTIVITY TODAY WILL
REMAIN FAIRLY ISOLATED AND MAINLY CONFINED TO HIGHER TERRAIN AREAS.
THE LACK OF ANY TRIGGER AND WEAK CONFLUENT ANTICYCLONIC FLOW ALOFT
WILL INHIBIT ANY WIDESPREAD STORM ACTIVITY TODAY.

THE UPPER HIGH CENTER WILL SHIFT EVEN FURTHER SOUTH INTO MEXICO ON
THURSDAY KEEPING OUR FLOW ALOFT OUT OF THE SOUTHWEST. GRADUAL DRYING
WILL CONTINUE UNDER THIS REGIME...ESPECIALLY WEST OF PHOENIX...BUT
MOISTURE LEVELS ACROSS THE EASTERN HALF OF ARIZONA WILL ONLY DIP
SLIGHTLY. FLOW ALOFT WILL BE LESS UNFAVORABLE DURING THE DAYTIME
HOURS THURSDAY...BUT ALSO WEAKER COMPARED TO TODAY. THIS MAY LEAD TO
A BIT MORE ACTIVITY OVER SOUTH-CENTRAL ARIZONA ON THURSDAY...BUT
WEAKER STEERING FLOW WILL LIKELY KEEP MUCH OF THE STORM ACTIVITY
OVER HIGHER TERRAIN AREAS AS STORMS SHOULD HAVE A DIFFICULT TIME
MIGRATING INTO THE LOWER ELEVATIONS. A BOOST IN TEMPERATURES IS
EXPECTED AS HEIGHTS ALOFT INCREASE SOMEWHAT AND SURFACE DEW POINTS
LOWER A FEW DEGREES. HIGHS ACROSS THE SOUTHEAST CALIFORNIA AND
SOUTHWEST ARIZONA DESERTS SHOULD REACH NEAR 110 DEGREES.

FRIDAY AND SATURDAY...
THE CENTER OF THE UPPER LEVEL ANTICYCLONE WILL POSITION TO OUR
SOUTH..AND ATMOSPHERIC MOISTURE WILL CONTINUE TO THIN OUT...WITH
FORECASTED PRECIPITABLE WATER POTENTIALLY DROPPING TO JUST ABOVE ONE
INCH. THE DRIER AIRMASS WILL SUPPORT WARMER TEMPERATURES FOR THE
LOWER DESERTS...WITH DAYTIME HIGHS FOR YUMA...EL CENTRO AND GILA
BEND AGAIN HITTING THE 110-112 DEGREE RANGE FRIDAY AND SATURDAY.
HOWEVER...THE UPPER LEVEL HIGH STARTS TO REBOUND OVER THE WEEKEND...
592DM 500MB HEIGHTS CENTERING ALONG THE AZ/NM BORDER...SO SOME
MOISTURE RETURN TO THE DESERT SOUTHWEST IS POSSIBLE. THIS MIGHT
OFFSET THE PROJECTED HOT TEMPERATURE FORECAST FOR THESE DAYS BY A
FEW DEGREES. OVER THE LAST NORMAL PERIOD 1981-2010...THE AVERAGE
LAST 110F DAY IN PHOENIX FALLS ON AUGUST 26TH...AND SEPTEMBER 6TH
FOR YUMA. WE COULD POTENTIALLY PUSH PAST THE AVERAGE LAST DAY IN THE
PHOENIX AREA BY THE END OF THE WEEKEND.

SUNDAY INTO TUESDAY...
A STRONG EASTERN PACIFIC UPPER LEVEL TROUGH APPROACHES THE PACIFIC
NORTHWEST AND NORTHERN CALIFORNIA COAST. STARTING LATE IN THE
WEEKEND...THE TROUGH BEGINS TO ENCROACH ON AND BREAK DOWN THE RIDGE
PATTERN OVER THE INTERMOUNTAIN WEST. WITH THE TREND FOR LOWER HEIGHTS
NOTED IN THE MODELS/ENSEMBLE SOLUTIONS... TEMPERATURES IN THE
EXTENDED WERE SUBTLY COOLED SUNDAY INTO EARLY NEXT WEEK WITH MOSTLY
BELOW NORMAL POPS ACROSS THE REGION.

&&

.AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND
KSDL...

THROUGH 18Z THU...SCT CLDS NEAR 8 THSD AGL...WITH SCT CIRRUS ABOVE.
WEST WIND 5 TO 10 KNOTS THROUGH 04Z THU...BECOMING LIGHT AND
VARIABLE.


SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

THROUGH 03Z THU...SCT CLDS NEAR 10 THSD AGL...WITH SCT CIRRUS ABOVE.
ISOLATED THUNDERSTORMS OVER THE NEARBY COASTAL MOUNTAIN RANGE.
SOUTHWEST WIND 5 TO 10 KNOTS. FROM 03Z THU THROUGH 18Z THU...MOSTLY
CLEAR. SOUTH WIND 5 TO 10 KNOTS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER... SATURDAY THROUGH WEDNESDAY... DRIER AND WARMER
WEATHER WILL SPREAD INTO REGION FROM THE WEST...HOWEVER A SLIGHT
CHANCE OF AFTERNOON AND EVENING TSTMS IS STILL FORECAST FOR THE
MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY. HIGH TEMPERATURES
THROUGH SUNDAY WILL BE WELL ABOVE NORMAL WITH HOTTER DESERTS IN
EXCESS OF 110...WITH SOME COOLING BACK TOWARD NORMAL EARLY NEXT
WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL INTO THE 10 TO 15
PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY ABOVE 15
PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES REACHING
25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST WINDS WILL
RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...PERCHA
AVIATION...VASQUEZ
FIRE WEATHER...VASQUEZ/CB




000
FXUS65 KPSR 270410
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
910 PM MST WED AUG 26 2015

&&

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD THROUGH THURSDAY.
STARTING FRIDAY THE DRIER AIR WILL PUSH FURTHER EAST CONFINING RAIN
CHANCES TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH
THE WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION... ALTHOUGH THE OVERALL CONVECTIVE ACTIVITY TODAY/THIS
EVENING HAS BEEN LESS THEN YESTERDAY ACROSS OUR CWA...AS
SOUTHWESTERLY FLOW ALOFT BEGINS TO GRADUALLY REDUCE THE AVAILABLE
MOISTURE ACROSS THE REGION...A FEW AREAS DID STILL SEE THUNDERSTORM
ACTIVITY. THE STRONGEST STORMS WERE OVER JOSHUA TREE NATIONAL PARK
THIS AFTERNOON...AS A COMBINATION OF A RICH MOISTURE PLUME THAT
SURGED INTO THE REGION THIS MORNING AND A WEAK SHORTWAVE THAT MOVED
OVER THE REGION HELPED TO TRIGGER STORMS THAT PRODUCED SIGNIFICANT
FLASH FLOODING OVER THE REGION. THE OTHER AREAS THAT SAW STORMS WERE
OVER SOUTHERN GILA COUNTY...WITH THE PINAL PEAK GAUGE REPORTING 2.74
INCH AND A COUPLE OF LOCATIONS IN THE GLOBE AREA SEEING OVER ONE
INCH...AND OVER THE MORE REMOTE AREAS OF LA PAZ AND NORTHERN YUMA
COUNTIES. GIVEN THE LATEST RADAR TRENDS AND HIGH-RES MODELS...IT
APPEARS THAT REST OF THE EVENING WILL BE QUIET...OTHER THEN SOME
LOCALLY GUSTY SOUTHEASTERLY BREEZES OVER THE NEXT COUPLE OF HOURS AS
A OUTFLOW BOUNDARY FROM STORMS OVER PIMA COUNTY MOVE NORTHWESTWARD
ACROSS SOUTH-CENTRAL AZ. AS FAR AS THE SHORT-TERM FORECAST FOR THE
REMAINDER OF TONIGHT...HAVE REDUCED POPS AND MADE SOME MINOR
ADJUSTMENTS TO THE HOURLY GRIDS.

&&

.PREVIOUS DISCUSSION... THE LACK OF LATE MORNING AND EARLY AFTERNOON
CLOUD COVER HAS ALLOWED FOR GOOD SOLAR HEATING AND MUCH OF THE AREA
DESTABILIZING. MOIST BOUNDARY LAYER CONDITIONS REMAIN IN PLACE WITH
SURFACE DEW POINTS IN THE LOWER 60S...BUT SOUTHWESTERLY WINDS ALOFT
HAVE BROUGHT IN DRYING CONDITIONS. AN UPPER LEVEL SHORTWAVE TROUGH
THAT MOVED THROUGH THE LOWER COLORADO RIVER VALLEY EARLY THIS
MORNING HAS QUICKLY PUSHED NORTHEASTWARD INTO NORTHWEST ARIZONA AND
SOUTHERN UTAH. WEAK CONFLUENT FLOW BEHIND THE SHORTWAVE TROUGH WILL
ACROSS AREAS FROM PHOENIX WESTWARD TO THE COLORADO RIVER. STORM
ACTIVITY ACROSS OUR AREA SO FAR TODAY HAS BEEN SLOW TO START...BUT
WE ARE STARTING TO SEE A FEW ISOLATED CELLS OVER THE HIGHEST PEAKS.
THOUGH PLENTY OF MOISTURE IS PRESENT...FEEL ACTIVITY TODAY WILL
REMAIN FAIRLY ISOLATED AND MAINLY CONFINED TO HIGHER TERRAIN AREAS.
THE LACK OF ANY TRIGGER AND WEAK CONFLUENT ANTICYCLONIC FLOW ALOFT
WILL INHIBIT ANY WIDESPREAD STORM ACTIVITY TODAY.

THE UPPER HIGH CENTER WILL SHIFT EVEN FURTHER SOUTH INTO MEXICO ON
THURSDAY KEEPING OUR FLOW ALOFT OUT OF THE SOUTHWEST. GRADUAL DRYING
WILL CONTINUE UNDER THIS REGIME...ESPECIALLY WEST OF PHOENIX...BUT
MOISTURE LEVELS ACROSS THE EASTERN HALF OF ARIZONA WILL ONLY DIP
SLIGHTLY. FLOW ALOFT WILL BE LESS UNFAVORABLE DURING THE DAYTIME
HOURS THURSDAY...BUT ALSO WEAKER COMPARED TO TODAY. THIS MAY LEAD TO
A BIT MORE ACTIVITY OVER SOUTH-CENTRAL ARIZONA ON THURSDAY...BUT
WEAKER STEERING FLOW WILL LIKELY KEEP MUCH OF THE STORM ACTIVITY
OVER HIGHER TERRAIN AREAS AS STORMS SHOULD HAVE A DIFFICULT TIME
MIGRATING INTO THE LOWER ELEVATIONS. A BOOST IN TEMPERATURES IS
EXPECTED AS HEIGHTS ALOFT INCREASE SOMEWHAT AND SURFACE DEW POINTS
LOWER A FEW DEGREES. HIGHS ACROSS THE SOUTHEAST CALIFORNIA AND
SOUTHWEST ARIZONA DESERTS SHOULD REACH NEAR 110 DEGREES.

FRIDAY AND SATURDAY...
THE CENTER OF THE UPPER LEVEL ANTICYCLONE WILL POSITION TO OUR
SOUTH..AND ATMOSPHERIC MOISTURE WILL CONTINUE TO THIN OUT...WITH
FORECASTED PRECIPITABLE WATER POTENTIALLY DROPPING TO JUST ABOVE ONE
INCH. THE DRIER AIRMASS WILL SUPPORT WARMER TEMPERATURES FOR THE
LOWER DESERTS...WITH DAYTIME HIGHS FOR YUMA...EL CENTRO AND GILA
BEND AGAIN HITTING THE 110-112 DEGREE RANGE FRIDAY AND SATURDAY.
HOWEVER...THE UPPER LEVEL HIGH STARTS TO REBOUND OVER THE WEEKEND...
592DM 500MB HEIGHTS CENTERING ALONG THE AZ/NM BORDER...SO SOME
MOISTURE RETURN TO THE DESERT SOUTHWEST IS POSSIBLE. THIS MIGHT
OFFSET THE PROJECTED HOT TEMPERATURE FORECAST FOR THESE DAYS BY A
FEW DEGREES. OVER THE LAST NORMAL PERIOD 1981-2010...THE AVERAGE
LAST 110F DAY IN PHOENIX FALLS ON AUGUST 26TH...AND SEPTEMBER 6TH
FOR YUMA. WE COULD POTENTIALLY PUSH PAST THE AVERAGE LAST DAY IN THE
PHOENIX AREA BY THE END OF THE WEEKEND.

SUNDAY INTO TUESDAY...
A STRONG EASTERN PACIFIC UPPER LEVEL TROUGH APPROACHES THE PACIFIC
NORTHWEST AND NORTHERN CALIFORNIA COAST. STARTING LATE IN THE
WEEKEND...THE TROUGH BEGINS TO ENCROACH ON AND BREAK DOWN THE RIDGE
PATTERN OVER THE INTERMOUNTAIN WEST. WITH THE TREND FOR LOWER HEIGHTS
NOTED IN THE MODELS/ENSEMBLE SOLUTIONS... TEMPERATURES IN THE
EXTENDED WERE SUBTLY COOLED SUNDAY INTO EARLY NEXT WEEK WITH MOSTLY
BELOW NORMAL POPS ACROSS THE REGION.

&&

.AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND
KSDL...

THROUGH 18Z THU...SCT CLDS NEAR 8 THSD AGL...WITH SCT CIRRUS ABOVE.
WEST WIND 5 TO 10 KNOTS THROUGH 04Z THU...BECOMING LIGHT AND
VARIABLE.


SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

THROUGH 03Z THU...SCT CLDS NEAR 10 THSD AGL...WITH SCT CIRRUS ABOVE.
ISOLATED THUNDERSTORMS OVER THE NEARBY COASTAL MOUNTAIN RANGE.
SOUTHWEST WIND 5 TO 10 KNOTS. FROM 03Z THU THROUGH 18Z THU...MOSTLY
CLEAR. SOUTH WIND 5 TO 10 KNOTS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER... SATURDAY THROUGH WEDNESDAY... DRIER AND WARMER
WEATHER WILL SPREAD INTO REGION FROM THE WEST...HOWEVER A SLIGHT
CHANCE OF AFTERNOON AND EVENING TSTMS IS STILL FORECAST FOR THE
MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY. HIGH TEMPERATURES
THROUGH SUNDAY WILL BE WELL ABOVE NORMAL WITH HOTTER DESERTS IN
EXCESS OF 110...WITH SOME COOLING BACK TOWARD NORMAL EARLY NEXT
WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL INTO THE 10 TO 15
PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY ABOVE 15
PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES REACHING
25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST WINDS WILL
RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...PERCHA
AVIATION...VASQUEZ
FIRE WEATHER...VASQUEZ/CB





000
FXUS65 KPSR 262153
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
253 PM MST WED AUG 26 2015

.UPDATE...AVIATION AND FIRE WEATHER DISCUSSION.

&&

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD THROUGH THURSDAY.
STARTING FRIDAY THE DRIER AIR WILL PUSH FURTHER EAST CONFINING RAIN
CHANCES TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH
THE WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION...
THE LACK OF LATE MORNING AND EARLY AFTERNOON CLOUD COVER HAS ALLOWED
FOR GOOD SOLAR HEATING AND MUCH OF THE AREA DESTABILIZING. MOIST
BOUNDARY LAYER CONDITIONS REMAIN IN PLACE WITH SURFACE DEW POINTS IN
THE LOWER 60S...BUT SOUTHWESTERLY WINDS ALOFT HAVE BROUGHT IN DRYING
CONDITIONS. AN UPPER LEVEL SHORTWAVE TROUGH THAT MOVED THROUGH THE
LOWER COLORADO RIVER VALLEY EARLY THIS MORNING HAS QUICKLY PUSHED
NORTHEASTWARD INTO NORTHWEST ARIZONA AND SOUTHERN UTAH. WEAK
CONFLUENT FLOW BEHIND THE SHORTWAVE TROUGH WILL ACROSS AREAS FROM
PHOENIX WESTWARD TO THE COLORADO RIVER. STORM ACTIVITY ACROSS OUR
AREA SO FAR TODAY HAS BEEN SLOW TO START...BUT WE ARE STARTING TO SEE
A FEW ISOLATED CELLS OVER THE HIGHEST PEAKS. THOUGH PLENTY OF
MOISTURE IS PRESENT...FEEL ACTIVITY TODAY WILL REMAIN FAIRLY ISOLATED
AND MAINLY CONFINED TO HIGHER TERRAIN AREAS. THE LACK OF ANY TRIGGER
AND WEAK CONFLUENT ANTICYCLONIC FLOW ALOFT WILL INHIBIT ANY
WIDESPREAD STORM ACTIVITY TODAY.

THE UPPER HIGH CENTER WILL SHIFT EVEN FURTHER SOUTH INTO MEXICO ON
THURSDAY KEEPING OUR FLOW ALOFT OUT OF THE SOUTHWEST. GRADUAL DRYING
WILL CONTINUE UNDER THIS REGIME...ESPECIALLY WEST OF PHOENIX...BUT
MOISTURE LEVELS ACROSS THE EASTERN HALF OF ARIZONA WILL ONLY DIP
SLIGHTLY. FLOW ALOFT WILL BE LESS UNFAVORABLE DURING THE DAYTIME
HOURS THURSDAY...BUT ALSO WEAKER COMPARED TO TODAY. THIS MAY LEAD TO
A BIT MORE ACTIVITY OVER SOUTH-CENTRAL ARIZONA ON THURSDAY...BUT
WEAKER STEERING FLOW WILL LIKELY KEEP MUCH OF THE STORM ACTIVITY
OVER HIGHER TERRAIN AREAS AS STORMS SHOULD HAVE A DIFFICULT TIME
MIGRATING INTO THE LOWER ELEVATIONS. A BOOST IN TEMPERATURES IS
EXPECTED AS HEIGHTS ALOFT INCREASE SOMEWHAT AND SURFACE DEW POINTS
LOWER A FEW DEGREES. HIGHS ACROSS THE SOUTHEAST CALIFORNIA AND
SOUTHWEST ARIZONA DESERTS SHOULD REACH NEAR 110 DEGREES.

FRIDAY AND SATURDAY...
THE CENTER OF THE UPPER LEVEL ANTICYCLONE WILL POSITION TO OUR
SOUTH..AND ATMOSPHERIC MOISTURE WILL CONTINUE TO THIN OUT...WITH
FORECASTED PRECIPITABLE WATER POTENTIALLY DROPPING TO JUST ABOVE ONE
INCH. THE DRIER AIRMASS WILL SUPPORT WARMER TEMPERATURES FOR THE
LOWER DESERTS...WITH DAYTIME HIGHS FOR YUMA...EL CENTRO AND GILA
BEND AGAIN HITTING THE 110-112 DEGREE RANGE FRIDAY AND SATURDAY.
HOWEVER...THE UPPER LEVEL HIGH STARTS TO REBOUND OVER THE WEEKEND...
592DM 500MB HEIGHTS CENTERING ALONG THE AZ/NM BORDER...SO SOME
MOISTURE RETURN TO THE DESERT SOUTHWEST IS POSSIBLE. THIS MIGHT
OFFSET THE PROJECTED HOT TEMPERATURE FORECAST FOR THESE DAYS BY A
FEW DEGREES. OVER THE LAST NORMAL PERIOD 1981-2010...THE AVERAGE
LAST 110F DAY IN PHOENIX FALLS ON AUGUST 26TH...AND SEPTEMBER 6TH
FOR YUMA. WE COULD POTENTIALLY PUSH PAST THE AVERAGE LAST DAY IN THE
PHOENIX AREA BY THE END OF THE WEEKEND.

SUNDAY INTO TUESDAY...
A STRONG EASTERN PACIFIC UPPER LEVEL TROUGH APPROACHES THE PACIFIC
NORTHWEST AND NORTHERN CALIFORNIA COAST. STARTING LATE IN THE
WEEKEND...THE TROUGH BEGINS TO ENCROACH ON AND BREAK DOWN THE RIDGE
PATTERN OVER THE INTERMOUNTAIN WEST. WITH THE TREND FOR LOWER HEIGHTS
NOTED IN THE MODELS/ENSEMBLE SOLUTIONS... TEMPERATURES IN THE
EXTENDED WERE SUBTLY COOLED SUNDAY INTO EARLY NEXT WEEK WITH MOSTLY
BELOW NORMAL POPS ACROSS THE REGION.

&&

.AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND
KSDL...

THROUGH 18Z THU...SCT CLDS NEAR 8 THSD AGL...WITH SCT CIRRUS ABOVE.
WEST WIND 5 TO 10 KNOTS THROUGH 04Z THU...BECOMING LIGHT AND
VARIABLE.


SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

THROUGH 03Z THU...SCT CLDS NEAR 10 THSD AGL...WITH SCT CIRRUS ABOVE.
ISOLATED THUNDERSTORMS OVER THE NEARBY COASTAL MOUNTAIN RANGE.
SOUTHWEST WIND 5 TO 10 KNOTS. FROM 03Z THU THROUGH 18Z THU...MOSTLY
CLEAR. SOUTH WIND 5 TO 10 KNOTS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER... SATURDAY THROUGH WEDNESDAY... DRIER AND WARMER
WEATHER WILL SPREAD INTO REGION FROM THE WEST...HOWEVER A SLIGHT
CHANCE OF AFTERNOON AND EVENING TSTMS IS STILL FORECAST FOR THE
MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY. HIGH TEMPERATURES
THROUGH SUNDAY WILL BE WELL ABOVE NORMAL WITH HOTTER DESERTS IN
EXCESS OF 110...WITH SOME COOLING BACK TOWARD NORMAL EARLY NEXT
WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL INTO THE 10 TO 15
PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY ABOVE 15
PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES REACHING
25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST WINDS WILL
RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...KUHLMAN/MEYERS
AVIATION...VASQUEZ
FIRE WEATHER...VASQUEZ/CB





000
FXUS65 KPSR 262153
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
253 PM MST WED AUG 26 2015

.UPDATE...AVIATION AND FIRE WEATHER DISCUSSION.

&&

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD THROUGH THURSDAY.
STARTING FRIDAY THE DRIER AIR WILL PUSH FURTHER EAST CONFINING RAIN
CHANCES TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH
THE WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION...
THE LACK OF LATE MORNING AND EARLY AFTERNOON CLOUD COVER HAS ALLOWED
FOR GOOD SOLAR HEATING AND MUCH OF THE AREA DESTABILIZING. MOIST
BOUNDARY LAYER CONDITIONS REMAIN IN PLACE WITH SURFACE DEW POINTS IN
THE LOWER 60S...BUT SOUTHWESTERLY WINDS ALOFT HAVE BROUGHT IN DRYING
CONDITIONS. AN UPPER LEVEL SHORTWAVE TROUGH THAT MOVED THROUGH THE
LOWER COLORADO RIVER VALLEY EARLY THIS MORNING HAS QUICKLY PUSHED
NORTHEASTWARD INTO NORTHWEST ARIZONA AND SOUTHERN UTAH. WEAK
CONFLUENT FLOW BEHIND THE SHORTWAVE TROUGH WILL ACROSS AREAS FROM
PHOENIX WESTWARD TO THE COLORADO RIVER. STORM ACTIVITY ACROSS OUR
AREA SO FAR TODAY HAS BEEN SLOW TO START...BUT WE ARE STARTING TO SEE
A FEW ISOLATED CELLS OVER THE HIGHEST PEAKS. THOUGH PLENTY OF
MOISTURE IS PRESENT...FEEL ACTIVITY TODAY WILL REMAIN FAIRLY ISOLATED
AND MAINLY CONFINED TO HIGHER TERRAIN AREAS. THE LACK OF ANY TRIGGER
AND WEAK CONFLUENT ANTICYCLONIC FLOW ALOFT WILL INHIBIT ANY
WIDESPREAD STORM ACTIVITY TODAY.

THE UPPER HIGH CENTER WILL SHIFT EVEN FURTHER SOUTH INTO MEXICO ON
THURSDAY KEEPING OUR FLOW ALOFT OUT OF THE SOUTHWEST. GRADUAL DRYING
WILL CONTINUE UNDER THIS REGIME...ESPECIALLY WEST OF PHOENIX...BUT
MOISTURE LEVELS ACROSS THE EASTERN HALF OF ARIZONA WILL ONLY DIP
SLIGHTLY. FLOW ALOFT WILL BE LESS UNFAVORABLE DURING THE DAYTIME
HOURS THURSDAY...BUT ALSO WEAKER COMPARED TO TODAY. THIS MAY LEAD TO
A BIT MORE ACTIVITY OVER SOUTH-CENTRAL ARIZONA ON THURSDAY...BUT
WEAKER STEERING FLOW WILL LIKELY KEEP MUCH OF THE STORM ACTIVITY
OVER HIGHER TERRAIN AREAS AS STORMS SHOULD HAVE A DIFFICULT TIME
MIGRATING INTO THE LOWER ELEVATIONS. A BOOST IN TEMPERATURES IS
EXPECTED AS HEIGHTS ALOFT INCREASE SOMEWHAT AND SURFACE DEW POINTS
LOWER A FEW DEGREES. HIGHS ACROSS THE SOUTHEAST CALIFORNIA AND
SOUTHWEST ARIZONA DESERTS SHOULD REACH NEAR 110 DEGREES.

FRIDAY AND SATURDAY...
THE CENTER OF THE UPPER LEVEL ANTICYCLONE WILL POSITION TO OUR
SOUTH..AND ATMOSPHERIC MOISTURE WILL CONTINUE TO THIN OUT...WITH
FORECASTED PRECIPITABLE WATER POTENTIALLY DROPPING TO JUST ABOVE ONE
INCH. THE DRIER AIRMASS WILL SUPPORT WARMER TEMPERATURES FOR THE
LOWER DESERTS...WITH DAYTIME HIGHS FOR YUMA...EL CENTRO AND GILA
BEND AGAIN HITTING THE 110-112 DEGREE RANGE FRIDAY AND SATURDAY.
HOWEVER...THE UPPER LEVEL HIGH STARTS TO REBOUND OVER THE WEEKEND...
592DM 500MB HEIGHTS CENTERING ALONG THE AZ/NM BORDER...SO SOME
MOISTURE RETURN TO THE DESERT SOUTHWEST IS POSSIBLE. THIS MIGHT
OFFSET THE PROJECTED HOT TEMPERATURE FORECAST FOR THESE DAYS BY A
FEW DEGREES. OVER THE LAST NORMAL PERIOD 1981-2010...THE AVERAGE
LAST 110F DAY IN PHOENIX FALLS ON AUGUST 26TH...AND SEPTEMBER 6TH
FOR YUMA. WE COULD POTENTIALLY PUSH PAST THE AVERAGE LAST DAY IN THE
PHOENIX AREA BY THE END OF THE WEEKEND.

SUNDAY INTO TUESDAY...
A STRONG EASTERN PACIFIC UPPER LEVEL TROUGH APPROACHES THE PACIFIC
NORTHWEST AND NORTHERN CALIFORNIA COAST. STARTING LATE IN THE
WEEKEND...THE TROUGH BEGINS TO ENCROACH ON AND BREAK DOWN THE RIDGE
PATTERN OVER THE INTERMOUNTAIN WEST. WITH THE TREND FOR LOWER HEIGHTS
NOTED IN THE MODELS/ENSEMBLE SOLUTIONS... TEMPERATURES IN THE
EXTENDED WERE SUBTLY COOLED SUNDAY INTO EARLY NEXT WEEK WITH MOSTLY
BELOW NORMAL POPS ACROSS THE REGION.

&&

.AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND
KSDL...

THROUGH 18Z THU...SCT CLDS NEAR 8 THSD AGL...WITH SCT CIRRUS ABOVE.
WEST WIND 5 TO 10 KNOTS THROUGH 04Z THU...BECOMING LIGHT AND
VARIABLE.


SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

THROUGH 03Z THU...SCT CLDS NEAR 10 THSD AGL...WITH SCT CIRRUS ABOVE.
ISOLATED THUNDERSTORMS OVER THE NEARBY COASTAL MOUNTAIN RANGE.
SOUTHWEST WIND 5 TO 10 KNOTS. FROM 03Z THU THROUGH 18Z THU...MOSTLY
CLEAR. SOUTH WIND 5 TO 10 KNOTS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER... SATURDAY THROUGH WEDNESDAY... DRIER AND WARMER
WEATHER WILL SPREAD INTO REGION FROM THE WEST...HOWEVER A SLIGHT
CHANCE OF AFTERNOON AND EVENING TSTMS IS STILL FORECAST FOR THE
MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY. HIGH TEMPERATURES
THROUGH SUNDAY WILL BE WELL ABOVE NORMAL WITH HOTTER DESERTS IN
EXCESS OF 110...WITH SOME COOLING BACK TOWARD NORMAL EARLY NEXT
WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL INTO THE 10 TO 15
PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY ABOVE 15
PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES REACHING
25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST WINDS WILL
RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS EXPECTED.


.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...KUHLMAN/MEYERS
AVIATION...VASQUEZ
FIRE WEATHER...VASQUEZ/CB




000
FXUS65 KPSR 262132
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
232 PM MST WED AUG 26 2015

.SYNOPSIS...
HIGH PRESSURE SHIFTING TO THE SOUTHEAST OF THE REGION IS BEGINNING TO
BRING IN SOME DRIER CONDITIONS FROM THE WEST...BUT MODEST MONSOON
MOISTURE WILL STILL PERSIST FROM PHOENIX EASTWARD THROUGH THURSDAY.
STARTING FRIDAY THE DRIER AIR WILL PUSH FURTHER EAST CONFINING RAIN
CHANCES TO HIGHER TERRAIN AREAS EAST OF PHOENIX. TEMPERATURES THROUGH
THE WEEKEND WILL REMAIN ABOVE NORMAL WITH LOWER DESERT TEMPERATURES
AROUND 110 DEGREES ACROSS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.

&&

.DISCUSSION...
THE LACK OF LATE MORNING AND EARLY AFTERNOON CLOUD COVER HAS ALLOWED
FOR GOOD SOLAR HEATING AND MUCH OF THE AREA DESTABILIZING. MOIST
BOUNDARY LAYER CONDITIONS REMAIN IN PLACE WITH SURFACE DEW POINTS IN
THE LOWER 60S...BUT SOUTHWESTERLY WINDS ALOFT HAVE BROUGHT IN DRYING
CONDITIONS. AN UPPER LEVEL SHORTWAVE TROUGH THAT MOVED THROUGH THE
LOWER COLORADO RIVER VALLEY EARLY THIS MORNING HAS QUICKLY PUSHED
NORTHEASTWARD INTO NORTHWEST ARIZONA AND SOUTHERN UTAH. WEAK
CONFLUENT FLOW BEHIND THE SHORTWAVE TROUGH WILL ACROSS AREAS FROM
PHOENIX WESTWARD TO THE COLORADO RIVER. STORM ACTIVITY ACROSS OUR
AREA SO FAR TODAY HAS BEEN SLOW TO START...BUT WE ARE STARTING TO SEE
A FEW ISOLATED CELLS OVER THE HIGHEST PEAKS. THOUGH PLENTY OF
MOISTURE IS PRESENT...FEEL ACTIVITY TODAY WILL REMAIN FAIRLY ISOLATED
AND MAINLY CONFINED TO HIGHER TERRAIN AREAS. THE LACK OF ANY TRIGGER
AND WEAK CONFLUENT ANTICYCLONIC FLOW ALOFT WILL INHIBIT ANY
WIDESPREAD STORM ACTIVITY TODAY.

THE UPPER HIGH CENTER WILL SHIFT EVEN FURTHER SOUTH INTO MEXICO ON
THURSDAY KEEPING OUR FLOW ALOFT OUT OF THE SOUTHWEST. GRADUAL DRYING
WILL CONTINUE UNDER THIS REGIME...ESPECIALLY WEST OF PHOENIX...BUT
MOISTURE LEVELS ACROSS THE EASTERN HALF OF ARIZONA WILL ONLY DIP
SLIGHTLY. FLOW ALOFT WILL BE LESS UNFAVORABLE DURING THE DAYTIME
HOURS THURSDAY...BUT ALSO WEAKER COMPARED TO TODAY. THIS MAY LEAD TO
A BIT MORE ACTIVITY OVER SOUTH-CENTRAL ARIZONA ON THURSDAY...BUT
WEAKER STEERING FLOW WILL LIKELY KEEP MUCH OF THE STORM ACTIVITY
OVER HIGHER TERRAIN AREAS AS STORMS SHOULD HAVE A DIFFICULT TIME
MIGRATING INTO THE LOWER ELEVATIONS. A BOOST IN TEMPERATURES IS
EXPECTED AS HEIGHTS ALOFT INCREASE SOMEWHAT AND SURFACE DEW POINTS
LOWER A FEW DEGREES. HIGHS ACROSS THE SOUTHEAST CALIFORNIA AND
SOUTHWEST ARIZONA DESERTS SHOULD REACH NEAR 110 DEGREES.

FRIDAY AND SATURDAY...
THE CENTER OF THE UPPER LEVEL ANTICYCLONE WILL POSITION TO OUR
SOUTH..AND ATMOSPHERIC MOISTURE WILL CONTINUE TO THIN OUT...WITH
FORECASTED PRECIPITABLE WATER POTENTIALLY DROPPING TO JUST ABOVE ONE
INCH. THE DRIER AIRMASS WILL SUPPORT WARMER TEMPERATURES FOR THE
LOWER DESERTS...WITH DAYTIME HIGHS FOR YUMA...EL CENTRO AND GILA
BEND AGAIN HITTING THE 110-112 DEGREE RANGE FRIDAY AND SATURDAY.
HOWEVER...THE UPPER LEVEL HIGH STARTS TO REBOUND OVER THE WEEKEND...
592DM 500MB HEIGHTS CENTERING ALONG THE AZ/NM BORDER...SO SOME
MOISTURE RETURN TO THE DESERT SOUTHWEST IS POSSIBLE. THIS MIGHT
OFFSET THE PROJECTED HOT TEMPERATURE FORECAST FOR THESE DAYS BY A
FEW DEGREES. OVER THE LAST NORMAL PERIOD 1981-2010...THE AVERAGE
LAST 110F DAY IN PHOENIX FALLS ON AUGUST 26TH...AND SEPTEMBER 6TH
FOR YUMA. WE COULD POTENTIALLY PUSH PAST THE AVERAGE LAST DAY IN THE
PHOENIX AREA BY THE END OF THE WEEKEND.

SUNDAY INTO TUESDAY...
A STRONG EASTERN PACIFIC UPPER LEVEL TROUGH APPROACHES THE PACIFIC
NORTHWEST AND NORTHERN CALIFORNIA COAST. STARTING LATE IN THE
WEEKEND...THE TROUGH BEGINS TO ENCROACH ON AND BREAK DOWN THE RIDGE
PATTERN OVER THE INTERMOUNTAIN WEST. WITH THE TREND FOR LOWER HEIGHTS
NOTED IN THE MODELS/ENSEMBLE SOLUTIONS... TEMPERATURES IN THE
EXTENDED WERE SUBTLY COOLED SUNDAY INTO EARLY NEXT WEEK WITH MOSTLY
BELOW NORMAL POPS ACROSS THE REGION.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...

NO SIGNIFICANT DISTURBANCES MOVING AROUND THE UPPER HIGH AND THROUGH
THE FLOW ALOFT...FLOW ALOFT SHIFTING MORE TOWARDS THE SOUTHWEST AND
CONFLUENCE ALOFT ALL POINT TO A REDUCED CHANCE FOR CONVECTION TODAY
OVER THE CENTRAL DESERTS. MOISTURE VALUES REMAIN ELEVATED SO CHANCES
FOR STORMS TODAY ARE NOT ZERO...BUT THEY ARE ONLY SLIGHT CHANCES AND
AS SUCH CONFIDENCE IN STORM DEVELOPMENT OR TIMING IS TOO LOW TO
MERIT ANY MENTION IN THE TAFS DURING THE 12Z PACKAGE. THUS EXPECT
MAINLY SCATTERED MID/HI LEVEL DECKS THIS MORNING WITH SOME HIGH
BASED CUMULUS DEVELOPING THIS AFTERNOON. BROKEN MID/HIGH LEVEL
DEBRIS DECKS OVERNIGHT TONIGHT ARE A BETTER BET AT THE TERMINALS AS
COMPARED TO ANY STORM ACTIVITY. WINDS TO BE RELATIVELY DIURNAL NEXT
24 HOURS AND NOT OVERLY STRONG...BUT SHOULD STORMS FORM NEAR THE
TERMINALS WINDS WOULD CERTAINLY BECOME MUCH STRONGER AND SHIFTY.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

LOW LEVEL MOISTURE REMAINS ELEVATED BUT OVERALL CHANCES FOR STORMS
NEXT 24 HOURS ARE SLIGHT AT BEST SO CONFIDENCE TOO LOW TO MERIT ANY
MENTION IN THE TAFS. EXPECT FEW-SCT MID/HI DECKS NEXT 24 HOURS WITH
SOME AFTERNOON/EVE CUMULUS POSSIBLE. WINDS WILL STAY RATHER LIGHT
AND FAVOR THE SOUTH/SOUTHEAST AT BOTH KIPL AND KBLH THROUGH THE
AFTERNOON BECOMING MORE SOUTHWESTERLY BY THIS EVENING.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
FRIDAY THROUGH TUESDAY...
DRIER AND WARMER WEATHER WILL SPREAD INTO REGION FROM THE
WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND EVENING TSTMS IS
STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY.
HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE NORMAL WITH
HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK TOWARD
NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL INTO
THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY
ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES
REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST
WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS
EXPECTED.

&&

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...KUHLMAN/MEYERS
AVIATION...CB
FIRE WEATHER...VASQUEZ/CB





000
FXUS65 KPSR 261654
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
954 AM MST WED AUG 26 2015

.SYNOPSIS...
HIGH PRESSURE HAS BECOME REESTABLISHED TO THE EAST OF ARIZONA AND
MOIST MONSOONAL FLOW HAS SETTLED INTO THE REGION. THESE CONDITIONS
WILL STILL SUPPORT CONTINUED SLIGHT RAIN CHANCES TODAY ACROSS THE
LOWER DESERTS AND HIGHER CHANCES OVER HIGHER TERRAIN AREAS. DRIER
CONDITIONS WILL GRADUALLY RETURN THURSDAY THROUGH THE END OF THE WEEK
ALONG WITH MUCH WARMER ABOVE NORMAL TEMPERATURES.

&&

.DISCUSSION...
THE ATMOSPHERE IS STARTING TO RECOVER FROM YESTERDAY`S STORM
ACTIVITY...BUT LESS FAVORABLE DRYING CONFLUENT FLOW ALOFT OUT OF THE
SOUTHWEST SHOULD RESULT IN MUCH LESS STORM ACTIVITY TODAY. WATER
VAPOR IMAGERY SHOWS AN EXITING SHORTWAVE MOVING INTO NORTHERN ARIZONA
FROM THE LOWER COLORADO RIVER VALLEY AND WEAK SUBSIDENCE BEHIND THIS
FEATURE WILL LIKELY ALSO HINDER ANY WIDESPREAD DEVELOPMENT. THE
LOWERED POPS CHANCES FOR TODAY STILL LOOK REASONABLE AND FEEL MOST OF
THE ACTIVITY WILL BE OVER SOUTHEAST AND EAST-CENTRAL ARIZONA WHERE
THERE IS A LACK OF CONFLUENT FLOW ALOFT. STILL COULD GET A FEW STORMS
TO THE WEST AND SOUTHWEST OF THE PHOENIX AREA...BUT THEY WILL HAVE
TO FIGHT THROUGH AN INVERSION FOUND BETWEEN 400-500MB SHOWN ON THE
12Z KPSR AND YUMA RAOBS. PREVIOUS DISCUSSION STILL APPLIES.

&&

.PREVIOUS DISCUSSION...
TODAY AND THURSDAY...
REGIONAL UPPER AIR PLOTS/SATELLITE IMAGERY SHOW THE UPPER LEVEL
RIDGE CURRENTLY CENTERED OVER COLORADO/NEW MEXICO THIS MORNING...
THE BROAD ANTICYCLONIC FLOW ALLOWING A CONSIDERABLE AMOUNT OF DEBRIS
CLOUDINESS FROM YESTERDAYS CONVECTION TO STREAM NORTHWARD OVER THE
REGION. A WEAK UPPER LEVEL DISTURBANCE IS ALSO NOTED IN THE WATER
VAPOR IMAGERY CENTERED OVER THE LOWER COLORADO RIVER NORTH OF
BLYTHE. THE GFS/ECMWF/NAM12 ALL INDICATE THAT THIS WEAK LOW WILL GET
PICKED UP IN THE ANTICYCLONIC FLOW AND RIDE OVER THE TOP OF THE
RIDGE INTO UTAH AND WYOMING LATER TODAY. BY THURSDAY MORNING...THE
LOW MOVES OFF TO THE LEE SIDE OF THE ROCKIES AND STRENGTHENS...
THEREBY SUPPRESSING THE RIDGE TO THE SOUTH WHERE IT WILL FINALLY
SETTLES A 595DM 500MB CENTER OVER SOUTHEAST AZ/SOUTHWEST NM THURSDAY
AFTERNOON.

THIS RATHER HASTY MODIFICATION AND REPOSITIONING OF THE UPPER LEVEL
RIDGE AXIS WILL QUICKLY RESULT IN A TRANSITION TO A DRIER
SOUTHWESTERLY FLOW ALOFT...EFFECTIVELY DRYING OUT THE ATMOSPHERE.
THIS GRADUAL DOWNWARD TREND OF MOISTURE AND MIXING RATIOS TO LESS
THAN 10G/KG WILL EFFECTIVELY KNOCK DOWN PRECIPITATION CHANCES...
ESPECIALLY OVER THE LOWER DESERTS. EVEN THOUGH PLENTIFUL MOISTURE
WILL LINGER FOR A DAY OR TWO...THE FLOW ALOFT ALSO BECOMES MORE
CONFLUENT AND SOMEWHAT SUBSIDENT IN NATURE...THWARTING DEEP MOIST
CONVECTION...SO STORMS ARE GOING TO STRUGGLE TO FORM AND PERSIST. AS
SUCH...TAILORED POPS DOWN INTO THE SLIGHT CHANCE CATEGORY FOR MOST
OF OUR CWA THIS AFTERNOON AND EVENING...KEEPING HIGHER CHANCES OVER
THE HIGHER TERRAIN OF THE WEST CENTRAL DESERTS IN LA PAZ
COUNTY...AND SOUTH-CENTRAL ARIZONA NORTH AND EAST OF PHOENIX. BY
THURSDAY AFTERNOON...POP CHANCES WILL EVEN BE LESS...WITH STORMS
AGAIN CONFINED TO THE MOUNTAINS NORTH AND EAST OF PHOENIX.

FRIDAY AND SATURDAY...
THE CENTER OF THE UPPER LEVEL ANTICYCLONE WILL POSITION TO OUR
SOUTH..AND ATMOSPHERIC MOISTURE WILL CONTINUE TO THIN OUT...WITH
FORECASTED PRECIPITABLE WATER POTENTIALLY DROPPING TO JUST ABOVE ONE
INCH. THE DRIER AIRMASS WILL SUPPORT WARMER TEMPERATURES FOR THE
LOWER DESERTS...WITH DAYTIME HIGHS FOR YUMA...EL CENTRO AND GILA
BEND AGAIN HITTING THE 110-112 DEGREE RANGE FRIDAY AND SATURDAY.
HOWEVER...THE UPPER LEVEL HIGH STARTS TO REBOUND OVER THE WEEKEND...
592DM 500MB HEIGHTS CENTERING ALONG THE AZ/NM BORDER...SO SOME
MOISTURE RETURN TO THE DESERT SOUTHWEST IS POSSIBLE. THIS MIGHT
OFFSET THE PROJECTED HOT TEMPERATURE FORECAST FOR THESE DAYS BY A
FEW DEGREES. OVER THE LAST NORMAL PERIOD 1981-2010...THE AVERAGE
LAST 110F DAY IN PHOENIX FALLS ON AUGUST 26TH...AND SEPTEMBER 6TH
FOR YUMA. WE COULD CERTAINLY PUSH PAST THE AVERAGE LAST DAY IN THE
PHOENIX AREA BY THE WEEKEND...AND WORK TO CINCH THE TOP SPOT FOR THE
WARMEST AUGUST ON RECORD AT BOTH LOCALES TO CLOSE OUT THE MONTH.

SUNDAY INTO TUESDAY...
A STRONG EASTERN PACIFIC UPPER LEVEL TROUGH APPROACHES THE PACIFIC
NORTHWEST AND NORTHERN CALIFORNIA COAST.  STARTING LATE IN THE
WEEKEND...THE TROUGH BEGINS TO ENCROACH ON AND BREAK DOWN THE RIDGE
PATTERN OVER THE INTERMOUNTAIN WEST. WITH THE TREND FOR LOWER
HEIGHTS NOTED IN THE MODELS/ENSEMBLE SOLUTIONS... TEMPERATURES IN
THE EXTENDED WERE SUBTLY COOLED SUNDAY INTO EARLY NEXT WEEK WITH
MOSTLY BELOW NORMAL POPS ACROSS THE REGION.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...

NO SIGNIFICANT DISTURBANCES MOVING AROUND THE UPPER HIGH AND THROUGH
THE FLOW ALOFT...FLOW ALOFT SHIFTING MORE TOWARDS THE SOUTHWEST AND
CONFLUENCE ALOFT ALL POINT TO A REDUCED CHANCE FOR CONVECTION TODAY
OVER THE CENTRAL DESERTS. MOISTURE VALUES REMAIN ELEVATED SO CHANCES
FOR STORMS TODAY ARE NOT ZERO...BUT THEY ARE ONLY SLIGHT CHANCES AND
AS SUCH CONFIDENCE IN STORM DEVELOPMENT OR TIMING IS TOO LOW TO
MERIT ANY MENTION IN THE TAFS DURING THE 12Z PACKAGE. THUS EXPECT
MAINLY SCATTERED MID/HI LEVEL DECKS THIS MORNING WITH SOME HIGH
BASED CUMULUS DEVELOPING THIS AFTERNOON. BROKEN MID/HIGH LEVEL
DEBRIS DECKS OVERNIGHT TONIGHT ARE A BETTER BET AT THE TERMINALS AS
COMPARED TO ANY STORM ACTIVITY. WINDS TO BE RELATIVELY DIURNAL NEXT
24 HOURS AND NOT OVERLY STRONG...BUT SHOULD STORMS FORM NEAR THE
TERMINALS WINDS WOULD CERTAINLY BECOME MUCH STRONGER AND SHIFTY.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

LOW LEVEL MOISTURE REMAINS ELEVATED BUT OVERALL CHANCES FOR STORMS
NEXT 24 HOURS ARE SLIGHT AT BEST SO CONFIDENCE TOO LOW TO MERIT ANY
MENTION IN THE TAFS. EXPECT FEW-SCT MID/HI DECKS NEXT 24 HOURS WITH
SOME AFTERNOON/EVE CUMULUS POSSIBLE. WINDS WILL STAY RATHER LIGHT
AND FAVOR THE SOUTH/SOUTHEAST AT BOTH KIPL AND KBLH THROUGH THE
AFTERNOON BECOMING MORE SOUTHWESTERLY BY THIS EVENING.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
FRIDAY THROUGH TUESDAY...
DRIER AND WARMER WEATHER WILL SPREAD INTO REGION FROM THE
WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND EVENING TSTMS IS
STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY.
HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE NORMAL WITH
HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK TOWARD
NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL INTO
THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY
ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES
REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST
WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS
EXPECTED.

&&

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...KUHLMAN
PREVIOUS DISCUSSION...MEYERS
AVIATION...CB
FIRE WEATHER...VASQUEZ/CB




000
FXUS65 KPSR 261654
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
954 AM MST WED AUG 26 2015

.SYNOPSIS...
HIGH PRESSURE HAS BECOME REESTABLISHED TO THE EAST OF ARIZONA AND
MOIST MONSOONAL FLOW HAS SETTLED INTO THE REGION. THESE CONDITIONS
WILL STILL SUPPORT CONTINUED SLIGHT RAIN CHANCES TODAY ACROSS THE
LOWER DESERTS AND HIGHER CHANCES OVER HIGHER TERRAIN AREAS. DRIER
CONDITIONS WILL GRADUALLY RETURN THURSDAY THROUGH THE END OF THE WEEK
ALONG WITH MUCH WARMER ABOVE NORMAL TEMPERATURES.

&&

.DISCUSSION...
THE ATMOSPHERE IS STARTING TO RECOVER FROM YESTERDAY`S STORM
ACTIVITY...BUT LESS FAVORABLE DRYING CONFLUENT FLOW ALOFT OUT OF THE
SOUTHWEST SHOULD RESULT IN MUCH LESS STORM ACTIVITY TODAY. WATER
VAPOR IMAGERY SHOWS AN EXITING SHORTWAVE MOVING INTO NORTHERN ARIZONA
FROM THE LOWER COLORADO RIVER VALLEY AND WEAK SUBSIDENCE BEHIND THIS
FEATURE WILL LIKELY ALSO HINDER ANY WIDESPREAD DEVELOPMENT. THE
LOWERED POPS CHANCES FOR TODAY STILL LOOK REASONABLE AND FEEL MOST OF
THE ACTIVITY WILL BE OVER SOUTHEAST AND EAST-CENTRAL ARIZONA WHERE
THERE IS A LACK OF CONFLUENT FLOW ALOFT. STILL COULD GET A FEW STORMS
TO THE WEST AND SOUTHWEST OF THE PHOENIX AREA...BUT THEY WILL HAVE
TO FIGHT THROUGH AN INVERSION FOUND BETWEEN 400-500MB SHOWN ON THE
12Z KPSR AND YUMA RAOBS. PREVIOUS DISCUSSION STILL APPLIES.

&&

.PREVIOUS DISCUSSION...
TODAY AND THURSDAY...
REGIONAL UPPER AIR PLOTS/SATELLITE IMAGERY SHOW THE UPPER LEVEL
RIDGE CURRENTLY CENTERED OVER COLORADO/NEW MEXICO THIS MORNING...
THE BROAD ANTICYCLONIC FLOW ALLOWING A CONSIDERABLE AMOUNT OF DEBRIS
CLOUDINESS FROM YESTERDAYS CONVECTION TO STREAM NORTHWARD OVER THE
REGION. A WEAK UPPER LEVEL DISTURBANCE IS ALSO NOTED IN THE WATER
VAPOR IMAGERY CENTERED OVER THE LOWER COLORADO RIVER NORTH OF
BLYTHE. THE GFS/ECMWF/NAM12 ALL INDICATE THAT THIS WEAK LOW WILL GET
PICKED UP IN THE ANTICYCLONIC FLOW AND RIDE OVER THE TOP OF THE
RIDGE INTO UTAH AND WYOMING LATER TODAY. BY THURSDAY MORNING...THE
LOW MOVES OFF TO THE LEE SIDE OF THE ROCKIES AND STRENGTHENS...
THEREBY SUPPRESSING THE RIDGE TO THE SOUTH WHERE IT WILL FINALLY
SETTLES A 595DM 500MB CENTER OVER SOUTHEAST AZ/SOUTHWEST NM THURSDAY
AFTERNOON.

THIS RATHER HASTY MODIFICATION AND REPOSITIONING OF THE UPPER LEVEL
RIDGE AXIS WILL QUICKLY RESULT IN A TRANSITION TO A DRIER
SOUTHWESTERLY FLOW ALOFT...EFFECTIVELY DRYING OUT THE ATMOSPHERE.
THIS GRADUAL DOWNWARD TREND OF MOISTURE AND MIXING RATIOS TO LESS
THAN 10G/KG WILL EFFECTIVELY KNOCK DOWN PRECIPITATION CHANCES...
ESPECIALLY OVER THE LOWER DESERTS. EVEN THOUGH PLENTIFUL MOISTURE
WILL LINGER FOR A DAY OR TWO...THE FLOW ALOFT ALSO BECOMES MORE
CONFLUENT AND SOMEWHAT SUBSIDENT IN NATURE...THWARTING DEEP MOIST
CONVECTION...SO STORMS ARE GOING TO STRUGGLE TO FORM AND PERSIST. AS
SUCH...TAILORED POPS DOWN INTO THE SLIGHT CHANCE CATEGORY FOR MOST
OF OUR CWA THIS AFTERNOON AND EVENING...KEEPING HIGHER CHANCES OVER
THE HIGHER TERRAIN OF THE WEST CENTRAL DESERTS IN LA PAZ
COUNTY...AND SOUTH-CENTRAL ARIZONA NORTH AND EAST OF PHOENIX. BY
THURSDAY AFTERNOON...POP CHANCES WILL EVEN BE LESS...WITH STORMS
AGAIN CONFINED TO THE MOUNTAINS NORTH AND EAST OF PHOENIX.

FRIDAY AND SATURDAY...
THE CENTER OF THE UPPER LEVEL ANTICYCLONE WILL POSITION TO OUR
SOUTH..AND ATMOSPHERIC MOISTURE WILL CONTINUE TO THIN OUT...WITH
FORECASTED PRECIPITABLE WATER POTENTIALLY DROPPING TO JUST ABOVE ONE
INCH. THE DRIER AIRMASS WILL SUPPORT WARMER TEMPERATURES FOR THE
LOWER DESERTS...WITH DAYTIME HIGHS FOR YUMA...EL CENTRO AND GILA
BEND AGAIN HITTING THE 110-112 DEGREE RANGE FRIDAY AND SATURDAY.
HOWEVER...THE UPPER LEVEL HIGH STARTS TO REBOUND OVER THE WEEKEND...
592DM 500MB HEIGHTS CENTERING ALONG THE AZ/NM BORDER...SO SOME
MOISTURE RETURN TO THE DESERT SOUTHWEST IS POSSIBLE. THIS MIGHT
OFFSET THE PROJECTED HOT TEMPERATURE FORECAST FOR THESE DAYS BY A
FEW DEGREES. OVER THE LAST NORMAL PERIOD 1981-2010...THE AVERAGE
LAST 110F DAY IN PHOENIX FALLS ON AUGUST 26TH...AND SEPTEMBER 6TH
FOR YUMA. WE COULD CERTAINLY PUSH PAST THE AVERAGE LAST DAY IN THE
PHOENIX AREA BY THE WEEKEND...AND WORK TO CINCH THE TOP SPOT FOR THE
WARMEST AUGUST ON RECORD AT BOTH LOCALES TO CLOSE OUT THE MONTH.

SUNDAY INTO TUESDAY...
A STRONG EASTERN PACIFIC UPPER LEVEL TROUGH APPROACHES THE PACIFIC
NORTHWEST AND NORTHERN CALIFORNIA COAST.  STARTING LATE IN THE
WEEKEND...THE TROUGH BEGINS TO ENCROACH ON AND BREAK DOWN THE RIDGE
PATTERN OVER THE INTERMOUNTAIN WEST. WITH THE TREND FOR LOWER
HEIGHTS NOTED IN THE MODELS/ENSEMBLE SOLUTIONS... TEMPERATURES IN
THE EXTENDED WERE SUBTLY COOLED SUNDAY INTO EARLY NEXT WEEK WITH
MOSTLY BELOW NORMAL POPS ACROSS THE REGION.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...

NO SIGNIFICANT DISTURBANCES MOVING AROUND THE UPPER HIGH AND THROUGH
THE FLOW ALOFT...FLOW ALOFT SHIFTING MORE TOWARDS THE SOUTHWEST AND
CONFLUENCE ALOFT ALL POINT TO A REDUCED CHANCE FOR CONVECTION TODAY
OVER THE CENTRAL DESERTS. MOISTURE VALUES REMAIN ELEVATED SO CHANCES
FOR STORMS TODAY ARE NOT ZERO...BUT THEY ARE ONLY SLIGHT CHANCES AND
AS SUCH CONFIDENCE IN STORM DEVELOPMENT OR TIMING IS TOO LOW TO
MERIT ANY MENTION IN THE TAFS DURING THE 12Z PACKAGE. THUS EXPECT
MAINLY SCATTERED MID/HI LEVEL DECKS THIS MORNING WITH SOME HIGH
BASED CUMULUS DEVELOPING THIS AFTERNOON. BROKEN MID/HIGH LEVEL
DEBRIS DECKS OVERNIGHT TONIGHT ARE A BETTER BET AT THE TERMINALS AS
COMPARED TO ANY STORM ACTIVITY. WINDS TO BE RELATIVELY DIURNAL NEXT
24 HOURS AND NOT OVERLY STRONG...BUT SHOULD STORMS FORM NEAR THE
TERMINALS WINDS WOULD CERTAINLY BECOME MUCH STRONGER AND SHIFTY.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

LOW LEVEL MOISTURE REMAINS ELEVATED BUT OVERALL CHANCES FOR STORMS
NEXT 24 HOURS ARE SLIGHT AT BEST SO CONFIDENCE TOO LOW TO MERIT ANY
MENTION IN THE TAFS. EXPECT FEW-SCT MID/HI DECKS NEXT 24 HOURS WITH
SOME AFTERNOON/EVE CUMULUS POSSIBLE. WINDS WILL STAY RATHER LIGHT
AND FAVOR THE SOUTH/SOUTHEAST AT BOTH KIPL AND KBLH THROUGH THE
AFTERNOON BECOMING MORE SOUTHWESTERLY BY THIS EVENING.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
FRIDAY THROUGH TUESDAY...
DRIER AND WARMER WEATHER WILL SPREAD INTO REGION FROM THE
WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND EVENING TSTMS IS
STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY.
HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE NORMAL WITH
HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK TOWARD
NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL INTO
THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY
ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES
REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST
WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS
EXPECTED.

&&

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...KUHLMAN
PREVIOUS DISCUSSION...MEYERS
AVIATION...CB
FIRE WEATHER...VASQUEZ/CB





000
FXUS65 KPSR 261211 AAA
AFDPSR

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PHOENIX AZ
510 AM MST WED AUG 26 2015

.UPDATE...UPDATED AVIATION AND FIRE WEATHER DISCUSSIONS.

&&

.SYNOPSIS...

HIGH PRESSURE HAS BECOME REESTABLISHED TO THE EAST OF ARIZONA AND
MOIST MONSOONAL FLOW HAS SETTLED INTO THE REGION. THESE CONDITIONS
WILL STILL SUPPORT CONTINUED SLIGHT RAIN CHANCES TODAY ACROSS THE
LOWER DESERTS. DRIER CONDITIONS WILL GRADUALLY RETURN THURSDAY
THROUGH THE END OF THE WEEK ALONG WITH MUCH WARMER ABOVE NORMAL
TEMPERATURES.

&&

.DISCUSSION...
TODAY AND THURSDAY...
REGIONAL UPPER AIR PLOTS/SATELLITE IMAGERY SHOW THE UPPER LEVEL
RIDGE CURRENTLY CENTERED OVER COLORADO/NEW MEXICO THIS MORNING...
THE BROAD ANTICYCLONIC FLOW ALLOWING A CONSIDERABLE AMOUNT OF DEBRIS
CLOUDINESS FROM YESTERDAYS CONVECTION TO STREAM NORTHWARD OVER THE
REGION. A WEAK UPPER LEVEL DISTURBANCE IS ALSO NOTED IN THE WATER
VAPOR IMAGERY CENTERED OVER THE LOWER COLORADO RIVER NORTH OF
BLYTHE. THE GFS/ECMWF/NAM12 ALL INDICATE THAT THIS WEAK LOW WILL GET
PICKED UP IN THE ANTICYCLONIC FLOW AND RIDE OVER THE TOP OF THE
RIDGE INTO UTAH AND WYOMING LATER TODAY. BY THURSDAY MORNING...THE
LOW MOVES OFF TO THE LEE SIDE OF THE ROCKIES AND STRENGTHENS...
THEREBY SUPPRESSING THE RIDGE TO THE SOUTH WHERE IT WILL FINALLY
SETTLES A 595DM 500MB CENTER OVER SOUTHEAST AZ/SOUTHWEST NM THURSDAY
AFTERNOON.

THIS RATHER HASTY MODIFICATION AND REPOSITIONING OF THE UPPER LEVEL
RIDGE AXIS WILL QUICKLY RESULT IN A TRANSITION TO A DRIER
SOUTHWESTERLY FLOW ALOFT...EFFECTIVELY DRYING OUT THE ATMOSPHERE.
THIS GRADUAL DOWNWARD TREND OF MOISTURE AND MIXING RATIOS TO LESS
THAN 10G/KG WILL EFFECTIVELY KNOCK DOWN PRECIPITATION CHANCES...
ESPECIALLY OVER THE LOWER DESERTS. EVEN THOUGH PLENTIFUL MOISTURE
WILL LINGER FOR A DAY OR TWO...THE FLOW ALOFT ALSO BECOMES MORE
CONFLUENT AND SOMEWHAT SUBSIDENT IN NATURE...THWARTING DEEP MOIST
CONVECTION...SO STORMS ARE GOING TO STRUGGLE TO FORM AND PERSIST. AS
SUCH...TAILORED POPS DOWN INTO THE SLIGHT CHANCE CATEGORY FOR MOST
OF OUR CWA THIS AFTERNOON AND EVENING...KEEPING HIGHER CHANCES OVER
THE HIGHER TERRAIN OF THE WEST CENTRAL DESERTS IN LA PAZ
COUNTY...AND SOUTH-CENTRAL ARIZONA NORTH AND EAST OF PHOENIX. BY
THURSDAY AFTERNOON...POP CHANCES WILL EVEN BE LESS...WITH STORMS
AGAIN CONFINED TO THE MOUNTAINS NORTH AND EAST OF PHOENIX.

FRIDAY AND SATURDAY...
THE CENTER OF THE UPPER LEVEL ANTICYCLONE WILL POSITION TO OUR
SOUTH..AND ATMOSPHERIC MOISTURE WILL CONTINUE TO THIN OUT...WITH
FORECASTED PRECIPITABLE WATER POTENTIALLY DROPPING TO JUST ABOVE ONE
INCH. THE DRIER AIRMASS WILL SUPPORT WARMER TEMPERATURES FOR THE
LOWER DESERTS...WITH DAYTIME HIGHS FOR YUMA...EL CENTRO AND GILA
BEND AGAIN HITTING THE 110-112 DEGREE RANGE FRIDAY AND SATURDAY.
HOWEVER...THE UPPER LEVEL HIGH STARTS TO REBOUND OVER THE WEEKEND...
592DM 500MB HEIGHTS CENTERING ALONG THE AZ/NM BORDER...SO SOME
MOISTURE RETURN TO THE DESERT SOUTHWEST IS POSSIBLE. THIS MIGHT
OFFSET THE PROJECTED HOT TEMPERATURE FORECAST FOR THESE DAYS BY A
FEW DEGREES. OVER THE LAST NORMAL PERIOD 1981-2010...THE AVERAGE
LAST 110F DAY IN PHOENIX FALLS ON AUGUST 26TH...AND SEPTEMBER 6TH
FOR YUMA. WE COULD CERTAINLY PUSH PAST THE AVERAGE LAST DAY IN THE
PHOENIX AREA BY THE WEEKEND...AND WORK TO CINCH THE TOP SPOT FOR THE
WARMEST AUGUST ON RECORD AT BOTH LOCALES TO CLOSE OUT THE MONTH.

SUNDAY INTO TUESDAY...
A STRONG EASTERN PACIFIC UPPER LEVEL TROUGH APPROACHES THE PACIFIC
NORTHWEST AND NORTHERN CALIFORNIA COAST.  STARTING LATE IN THE
WEEKEND...THE TROUGH BEGINS TO ENCROACH ON AND BREAK DOWN THE RIDGE
PATTERN OVER THE INTERMOUNTAIN WEST. WITH THE TREND FOR LOWER
HEIGHTS NOTED IN THE MODELS/ENSEMBLE SOLUTIONS... TEMPERATURES IN
THE EXTENDED WERE SUBTLY COOLED SUNDAY INTO EARLY NEXT WEEK WITH
MOSTLY BELOW NORMAL POPS ACROSS THE REGION.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...

NO SIGNIFICANT DISTURBANCES MOVING AROUND THE UPPER HIGH AND THROUGH
THE FOW ALOFT...FLOW ALOFT SHIFTING MORE TOWARDS THE SOUTHWEST AND
CONFLUENCE ALOFT ALL POINT TO A REDUCED CHANCE FOR CONVECTION TODAY
OVER THE CENTRAL DESERTS. MOISTURE VALUES REMAIN ELEVATED SO CHANCES
FOR STORMS TODAY ARE NOT ZERO...BUT THEY ARE ONLY SLIGHT CHANCES AND
AS SUCH CONFIDENCE IN STORM DEVELOPMENT OR TIMING IS TOO LOW TO
MERIT ANY MENTION IN THE TAFS DURING THE 12Z PACKAGE. THUS EXPECT
MAINLY SCATTERED MID/HI LEVEL DECKS THIS MORNING WITH SOME HIGH
BASED CUMULUS DEVELOPING THIS AFTERNOON. BROKEN MID/HIGH LEVEL
DEBRIS DECKS OVERNIGHT TONIGHT ARE A BETTER BET AT THE TERMINALS AS
COMPARED TO ANY STORM ACTIVITY. WINDS TO BE RELATIVELY DIURNAL NEXT
24 HOURS AND NOT OVERLY STRONG...BUT SHOULD STORMS FORM NEAR THE
TERMINALS WINDS WOULD CERTAINLY BECOME MUCH STRONGER AND SHIFTY.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

LOW LEVEL MOISTURE REMAINS ELEVATED BUT OVERALL CHANCES FOR STORMS
NEXT 24 HOURS ARE SLIGHT AT BEST SO CONFIDENCE TOO LOW TO MERIT ANY
MENTION IN THE TAFS. EXPECT FEW-SCT MID/HI DECKS NEXT 24 HOURS WITH
SOME AFTERNOON/EVE CUMULUS POSSIBLE. WINDS WILL STAY RATHER LIGHT
AND FAVOR THE SOUTH/SOUTHEAST AT BOTH KIPL AND KBLH THROUGH THE
AFTERNOON BECOMING MORE SOUTHWESTERLY BY THIS EVENING.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
FRIDAY THROUGH TUESDAY...
DRIER AND WARMER WEATHER WILL SPREAD INTO REGION FROM THE
WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND EVENING TSTMS IS
STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY.
HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE NORMAL WITH
HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK TOWARD
NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL INTO
THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY
ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES
REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST
WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS
EXPECTED.

&&

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.WINDS BECOMING VRB 25-35 KTS
IN VCNTY TSTMS. OTHERWISE

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...MEYERS
AVIATION...CB
FIRE WEATHER...VASQUEZ/CB





000
FXUS65 KPSR 261211 AAA
AFDPSR

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PHOENIX AZ
510 AM MST WED AUG 26 2015

.UPDATE...UPDATED AVIATION AND FIRE WEATHER DISCUSSIONS.

&&

.SYNOPSIS...

HIGH PRESSURE HAS BECOME REESTABLISHED TO THE EAST OF ARIZONA AND
MOIST MONSOONAL FLOW HAS SETTLED INTO THE REGION. THESE CONDITIONS
WILL STILL SUPPORT CONTINUED SLIGHT RAIN CHANCES TODAY ACROSS THE
LOWER DESERTS. DRIER CONDITIONS WILL GRADUALLY RETURN THURSDAY
THROUGH THE END OF THE WEEK ALONG WITH MUCH WARMER ABOVE NORMAL
TEMPERATURES.

&&

.DISCUSSION...
TODAY AND THURSDAY...
REGIONAL UPPER AIR PLOTS/SATELLITE IMAGERY SHOW THE UPPER LEVEL
RIDGE CURRENTLY CENTERED OVER COLORADO/NEW MEXICO THIS MORNING...
THE BROAD ANTICYCLONIC FLOW ALLOWING A CONSIDERABLE AMOUNT OF DEBRIS
CLOUDINESS FROM YESTERDAYS CONVECTION TO STREAM NORTHWARD OVER THE
REGION. A WEAK UPPER LEVEL DISTURBANCE IS ALSO NOTED IN THE WATER
VAPOR IMAGERY CENTERED OVER THE LOWER COLORADO RIVER NORTH OF
BLYTHE. THE GFS/ECMWF/NAM12 ALL INDICATE THAT THIS WEAK LOW WILL GET
PICKED UP IN THE ANTICYCLONIC FLOW AND RIDE OVER THE TOP OF THE
RIDGE INTO UTAH AND WYOMING LATER TODAY. BY THURSDAY MORNING...THE
LOW MOVES OFF TO THE LEE SIDE OF THE ROCKIES AND STRENGTHENS...
THEREBY SUPPRESSING THE RIDGE TO THE SOUTH WHERE IT WILL FINALLY
SETTLES A 595DM 500MB CENTER OVER SOUTHEAST AZ/SOUTHWEST NM THURSDAY
AFTERNOON.

THIS RATHER HASTY MODIFICATION AND REPOSITIONING OF THE UPPER LEVEL
RIDGE AXIS WILL QUICKLY RESULT IN A TRANSITION TO A DRIER
SOUTHWESTERLY FLOW ALOFT...EFFECTIVELY DRYING OUT THE ATMOSPHERE.
THIS GRADUAL DOWNWARD TREND OF MOISTURE AND MIXING RATIOS TO LESS
THAN 10G/KG WILL EFFECTIVELY KNOCK DOWN PRECIPITATION CHANCES...
ESPECIALLY OVER THE LOWER DESERTS. EVEN THOUGH PLENTIFUL MOISTURE
WILL LINGER FOR A DAY OR TWO...THE FLOW ALOFT ALSO BECOMES MORE
CONFLUENT AND SOMEWHAT SUBSIDENT IN NATURE...THWARTING DEEP MOIST
CONVECTION...SO STORMS ARE GOING TO STRUGGLE TO FORM AND PERSIST. AS
SUCH...TAILORED POPS DOWN INTO THE SLIGHT CHANCE CATEGORY FOR MOST
OF OUR CWA THIS AFTERNOON AND EVENING...KEEPING HIGHER CHANCES OVER
THE HIGHER TERRAIN OF THE WEST CENTRAL DESERTS IN LA PAZ
COUNTY...AND SOUTH-CENTRAL ARIZONA NORTH AND EAST OF PHOENIX. BY
THURSDAY AFTERNOON...POP CHANCES WILL EVEN BE LESS...WITH STORMS
AGAIN CONFINED TO THE MOUNTAINS NORTH AND EAST OF PHOENIX.

FRIDAY AND SATURDAY...
THE CENTER OF THE UPPER LEVEL ANTICYCLONE WILL POSITION TO OUR
SOUTH..AND ATMOSPHERIC MOISTURE WILL CONTINUE TO THIN OUT...WITH
FORECASTED PRECIPITABLE WATER POTENTIALLY DROPPING TO JUST ABOVE ONE
INCH. THE DRIER AIRMASS WILL SUPPORT WARMER TEMPERATURES FOR THE
LOWER DESERTS...WITH DAYTIME HIGHS FOR YUMA...EL CENTRO AND GILA
BEND AGAIN HITTING THE 110-112 DEGREE RANGE FRIDAY AND SATURDAY.
HOWEVER...THE UPPER LEVEL HIGH STARTS TO REBOUND OVER THE WEEKEND...
592DM 500MB HEIGHTS CENTERING ALONG THE AZ/NM BORDER...SO SOME
MOISTURE RETURN TO THE DESERT SOUTHWEST IS POSSIBLE. THIS MIGHT
OFFSET THE PROJECTED HOT TEMPERATURE FORECAST FOR THESE DAYS BY A
FEW DEGREES. OVER THE LAST NORMAL PERIOD 1981-2010...THE AVERAGE
LAST 110F DAY IN PHOENIX FALLS ON AUGUST 26TH...AND SEPTEMBER 6TH
FOR YUMA. WE COULD CERTAINLY PUSH PAST THE AVERAGE LAST DAY IN THE
PHOENIX AREA BY THE WEEKEND...AND WORK TO CINCH THE TOP SPOT FOR THE
WARMEST AUGUST ON RECORD AT BOTH LOCALES TO CLOSE OUT THE MONTH.

SUNDAY INTO TUESDAY...
A STRONG EASTERN PACIFIC UPPER LEVEL TROUGH APPROACHES THE PACIFIC
NORTHWEST AND NORTHERN CALIFORNIA COAST.  STARTING LATE IN THE
WEEKEND...THE TROUGH BEGINS TO ENCROACH ON AND BREAK DOWN THE RIDGE
PATTERN OVER THE INTERMOUNTAIN WEST. WITH THE TREND FOR LOWER
HEIGHTS NOTED IN THE MODELS/ENSEMBLE SOLUTIONS... TEMPERATURES IN
THE EXTENDED WERE SUBTLY COOLED SUNDAY INTO EARLY NEXT WEEK WITH
MOSTLY BELOW NORMAL POPS ACROSS THE REGION.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...

NO SIGNIFICANT DISTURBANCES MOVING AROUND THE UPPER HIGH AND THROUGH
THE FOW ALOFT...FLOW ALOFT SHIFTING MORE TOWARDS THE SOUTHWEST AND
CONFLUENCE ALOFT ALL POINT TO A REDUCED CHANCE FOR CONVECTION TODAY
OVER THE CENTRAL DESERTS. MOISTURE VALUES REMAIN ELEVATED SO CHANCES
FOR STORMS TODAY ARE NOT ZERO...BUT THEY ARE ONLY SLIGHT CHANCES AND
AS SUCH CONFIDENCE IN STORM DEVELOPMENT OR TIMING IS TOO LOW TO
MERIT ANY MENTION IN THE TAFS DURING THE 12Z PACKAGE. THUS EXPECT
MAINLY SCATTERED MID/HI LEVEL DECKS THIS MORNING WITH SOME HIGH
BASED CUMULUS DEVELOPING THIS AFTERNOON. BROKEN MID/HIGH LEVEL
DEBRIS DECKS OVERNIGHT TONIGHT ARE A BETTER BET AT THE TERMINALS AS
COMPARED TO ANY STORM ACTIVITY. WINDS TO BE RELATIVELY DIURNAL NEXT
24 HOURS AND NOT OVERLY STRONG...BUT SHOULD STORMS FORM NEAR THE
TERMINALS WINDS WOULD CERTAINLY BECOME MUCH STRONGER AND SHIFTY.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

LOW LEVEL MOISTURE REMAINS ELEVATED BUT OVERALL CHANCES FOR STORMS
NEXT 24 HOURS ARE SLIGHT AT BEST SO CONFIDENCE TOO LOW TO MERIT ANY
MENTION IN THE TAFS. EXPECT FEW-SCT MID/HI DECKS NEXT 24 HOURS WITH
SOME AFTERNOON/EVE CUMULUS POSSIBLE. WINDS WILL STAY RATHER LIGHT
AND FAVOR THE SOUTH/SOUTHEAST AT BOTH KIPL AND KBLH THROUGH THE
AFTERNOON BECOMING MORE SOUTHWESTERLY BY THIS EVENING.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
FRIDAY THROUGH TUESDAY...
DRIER AND WARMER WEATHER WILL SPREAD INTO REGION FROM THE
WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND EVENING TSTMS IS
STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY.
HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE NORMAL WITH
HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK TOWARD
NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL INTO
THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY
ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES
REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST
WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS
EXPECTED.

&&

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.WINDS BECOMING VRB 25-35 KTS
IN VCNTY TSTMS. OTHERWISE

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...MEYERS
AVIATION...CB
FIRE WEATHER...VASQUEZ/CB




000
FXUS65 KPSR 261211 AAA
AFDPSR

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PHOENIX AZ
510 AM MST WED AUG 26 2015

.UPDATE...UPDATED AVIATION AND FIRE WEATHER DISCUSSIONS.

&&

.SYNOPSIS...

HIGH PRESSURE HAS BECOME REESTABLISHED TO THE EAST OF ARIZONA AND
MOIST MONSOONAL FLOW HAS SETTLED INTO THE REGION. THESE CONDITIONS
WILL STILL SUPPORT CONTINUED SLIGHT RAIN CHANCES TODAY ACROSS THE
LOWER DESERTS. DRIER CONDITIONS WILL GRADUALLY RETURN THURSDAY
THROUGH THE END OF THE WEEK ALONG WITH MUCH WARMER ABOVE NORMAL
TEMPERATURES.

&&

.DISCUSSION...
TODAY AND THURSDAY...
REGIONAL UPPER AIR PLOTS/SATELLITE IMAGERY SHOW THE UPPER LEVEL
RIDGE CURRENTLY CENTERED OVER COLORADO/NEW MEXICO THIS MORNING...
THE BROAD ANTICYCLONIC FLOW ALLOWING A CONSIDERABLE AMOUNT OF DEBRIS
CLOUDINESS FROM YESTERDAYS CONVECTION TO STREAM NORTHWARD OVER THE
REGION. A WEAK UPPER LEVEL DISTURBANCE IS ALSO NOTED IN THE WATER
VAPOR IMAGERY CENTERED OVER THE LOWER COLORADO RIVER NORTH OF
BLYTHE. THE GFS/ECMWF/NAM12 ALL INDICATE THAT THIS WEAK LOW WILL GET
PICKED UP IN THE ANTICYCLONIC FLOW AND RIDE OVER THE TOP OF THE
RIDGE INTO UTAH AND WYOMING LATER TODAY. BY THURSDAY MORNING...THE
LOW MOVES OFF TO THE LEE SIDE OF THE ROCKIES AND STRENGTHENS...
THEREBY SUPPRESSING THE RIDGE TO THE SOUTH WHERE IT WILL FINALLY
SETTLES A 595DM 500MB CENTER OVER SOUTHEAST AZ/SOUTHWEST NM THURSDAY
AFTERNOON.

THIS RATHER HASTY MODIFICATION AND REPOSITIONING OF THE UPPER LEVEL
RIDGE AXIS WILL QUICKLY RESULT IN A TRANSITION TO A DRIER
SOUTHWESTERLY FLOW ALOFT...EFFECTIVELY DRYING OUT THE ATMOSPHERE.
THIS GRADUAL DOWNWARD TREND OF MOISTURE AND MIXING RATIOS TO LESS
THAN 10G/KG WILL EFFECTIVELY KNOCK DOWN PRECIPITATION CHANCES...
ESPECIALLY OVER THE LOWER DESERTS. EVEN THOUGH PLENTIFUL MOISTURE
WILL LINGER FOR A DAY OR TWO...THE FLOW ALOFT ALSO BECOMES MORE
CONFLUENT AND SOMEWHAT SUBSIDENT IN NATURE...THWARTING DEEP MOIST
CONVECTION...SO STORMS ARE GOING TO STRUGGLE TO FORM AND PERSIST. AS
SUCH...TAILORED POPS DOWN INTO THE SLIGHT CHANCE CATEGORY FOR MOST
OF OUR CWA THIS AFTERNOON AND EVENING...KEEPING HIGHER CHANCES OVER
THE HIGHER TERRAIN OF THE WEST CENTRAL DESERTS IN LA PAZ
COUNTY...AND SOUTH-CENTRAL ARIZONA NORTH AND EAST OF PHOENIX. BY
THURSDAY AFTERNOON...POP CHANCES WILL EVEN BE LESS...WITH STORMS
AGAIN CONFINED TO THE MOUNTAINS NORTH AND EAST OF PHOENIX.

FRIDAY AND SATURDAY...
THE CENTER OF THE UPPER LEVEL ANTICYCLONE WILL POSITION TO OUR
SOUTH..AND ATMOSPHERIC MOISTURE WILL CONTINUE TO THIN OUT...WITH
FORECASTED PRECIPITABLE WATER POTENTIALLY DROPPING TO JUST ABOVE ONE
INCH. THE DRIER AIRMASS WILL SUPPORT WARMER TEMPERATURES FOR THE
LOWER DESERTS...WITH DAYTIME HIGHS FOR YUMA...EL CENTRO AND GILA
BEND AGAIN HITTING THE 110-112 DEGREE RANGE FRIDAY AND SATURDAY.
HOWEVER...THE UPPER LEVEL HIGH STARTS TO REBOUND OVER THE WEEKEND...
592DM 500MB HEIGHTS CENTERING ALONG THE AZ/NM BORDER...SO SOME
MOISTURE RETURN TO THE DESERT SOUTHWEST IS POSSIBLE. THIS MIGHT
OFFSET THE PROJECTED HOT TEMPERATURE FORECAST FOR THESE DAYS BY A
FEW DEGREES. OVER THE LAST NORMAL PERIOD 1981-2010...THE AVERAGE
LAST 110F DAY IN PHOENIX FALLS ON AUGUST 26TH...AND SEPTEMBER 6TH
FOR YUMA. WE COULD CERTAINLY PUSH PAST THE AVERAGE LAST DAY IN THE
PHOENIX AREA BY THE WEEKEND...AND WORK TO CINCH THE TOP SPOT FOR THE
WARMEST AUGUST ON RECORD AT BOTH LOCALES TO CLOSE OUT THE MONTH.

SUNDAY INTO TUESDAY...
A STRONG EASTERN PACIFIC UPPER LEVEL TROUGH APPROACHES THE PACIFIC
NORTHWEST AND NORTHERN CALIFORNIA COAST.  STARTING LATE IN THE
WEEKEND...THE TROUGH BEGINS TO ENCROACH ON AND BREAK DOWN THE RIDGE
PATTERN OVER THE INTERMOUNTAIN WEST. WITH THE TREND FOR LOWER
HEIGHTS NOTED IN THE MODELS/ENSEMBLE SOLUTIONS... TEMPERATURES IN
THE EXTENDED WERE SUBTLY COOLED SUNDAY INTO EARLY NEXT WEEK WITH
MOSTLY BELOW NORMAL POPS ACROSS THE REGION.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...

NO SIGNIFICANT DISTURBANCES MOVING AROUND THE UPPER HIGH AND THROUGH
THE FOW ALOFT...FLOW ALOFT SHIFTING MORE TOWARDS THE SOUTHWEST AND
CONFLUENCE ALOFT ALL POINT TO A REDUCED CHANCE FOR CONVECTION TODAY
OVER THE CENTRAL DESERTS. MOISTURE VALUES REMAIN ELEVATED SO CHANCES
FOR STORMS TODAY ARE NOT ZERO...BUT THEY ARE ONLY SLIGHT CHANCES AND
AS SUCH CONFIDENCE IN STORM DEVELOPMENT OR TIMING IS TOO LOW TO
MERIT ANY MENTION IN THE TAFS DURING THE 12Z PACKAGE. THUS EXPECT
MAINLY SCATTERED MID/HI LEVEL DECKS THIS MORNING WITH SOME HIGH
BASED CUMULUS DEVELOPING THIS AFTERNOON. BROKEN MID/HIGH LEVEL
DEBRIS DECKS OVERNIGHT TONIGHT ARE A BETTER BET AT THE TERMINALS AS
COMPARED TO ANY STORM ACTIVITY. WINDS TO BE RELATIVELY DIURNAL NEXT
24 HOURS AND NOT OVERLY STRONG...BUT SHOULD STORMS FORM NEAR THE
TERMINALS WINDS WOULD CERTAINLY BECOME MUCH STRONGER AND SHIFTY.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

LOW LEVEL MOISTURE REMAINS ELEVATED BUT OVERALL CHANCES FOR STORMS
NEXT 24 HOURS ARE SLIGHT AT BEST SO CONFIDENCE TOO LOW TO MERIT ANY
MENTION IN THE TAFS. EXPECT FEW-SCT MID/HI DECKS NEXT 24 HOURS WITH
SOME AFTERNOON/EVE CUMULUS POSSIBLE. WINDS WILL STAY RATHER LIGHT
AND FAVOR THE SOUTH/SOUTHEAST AT BOTH KIPL AND KBLH THROUGH THE
AFTERNOON BECOMING MORE SOUTHWESTERLY BY THIS EVENING.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
FRIDAY THROUGH TUESDAY...
DRIER AND WARMER WEATHER WILL SPREAD INTO REGION FROM THE
WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND EVENING TSTMS IS
STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY.
HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE NORMAL WITH
HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK TOWARD
NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL INTO
THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY
ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES
REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST
WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS
EXPECTED.

&&

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.WINDS BECOMING VRB 25-35 KTS
IN VCNTY TSTMS. OTHERWISE

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...MEYERS
AVIATION...CB
FIRE WEATHER...VASQUEZ/CB




000
FXUS65 KPSR 261211 AAA
AFDPSR

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PHOENIX AZ
510 AM MST WED AUG 26 2015

.UPDATE...UPDATED AVIATION AND FIRE WEATHER DISCUSSIONS.

&&

.SYNOPSIS...

HIGH PRESSURE HAS BECOME REESTABLISHED TO THE EAST OF ARIZONA AND
MOIST MONSOONAL FLOW HAS SETTLED INTO THE REGION. THESE CONDITIONS
WILL STILL SUPPORT CONTINUED SLIGHT RAIN CHANCES TODAY ACROSS THE
LOWER DESERTS. DRIER CONDITIONS WILL GRADUALLY RETURN THURSDAY
THROUGH THE END OF THE WEEK ALONG WITH MUCH WARMER ABOVE NORMAL
TEMPERATURES.

&&

.DISCUSSION...
TODAY AND THURSDAY...
REGIONAL UPPER AIR PLOTS/SATELLITE IMAGERY SHOW THE UPPER LEVEL
RIDGE CURRENTLY CENTERED OVER COLORADO/NEW MEXICO THIS MORNING...
THE BROAD ANTICYCLONIC FLOW ALLOWING A CONSIDERABLE AMOUNT OF DEBRIS
CLOUDINESS FROM YESTERDAYS CONVECTION TO STREAM NORTHWARD OVER THE
REGION. A WEAK UPPER LEVEL DISTURBANCE IS ALSO NOTED IN THE WATER
VAPOR IMAGERY CENTERED OVER THE LOWER COLORADO RIVER NORTH OF
BLYTHE. THE GFS/ECMWF/NAM12 ALL INDICATE THAT THIS WEAK LOW WILL GET
PICKED UP IN THE ANTICYCLONIC FLOW AND RIDE OVER THE TOP OF THE
RIDGE INTO UTAH AND WYOMING LATER TODAY. BY THURSDAY MORNING...THE
LOW MOVES OFF TO THE LEE SIDE OF THE ROCKIES AND STRENGTHENS...
THEREBY SUPPRESSING THE RIDGE TO THE SOUTH WHERE IT WILL FINALLY
SETTLES A 595DM 500MB CENTER OVER SOUTHEAST AZ/SOUTHWEST NM THURSDAY
AFTERNOON.

THIS RATHER HASTY MODIFICATION AND REPOSITIONING OF THE UPPER LEVEL
RIDGE AXIS WILL QUICKLY RESULT IN A TRANSITION TO A DRIER
SOUTHWESTERLY FLOW ALOFT...EFFECTIVELY DRYING OUT THE ATMOSPHERE.
THIS GRADUAL DOWNWARD TREND OF MOISTURE AND MIXING RATIOS TO LESS
THAN 10G/KG WILL EFFECTIVELY KNOCK DOWN PRECIPITATION CHANCES...
ESPECIALLY OVER THE LOWER DESERTS. EVEN THOUGH PLENTIFUL MOISTURE
WILL LINGER FOR A DAY OR TWO...THE FLOW ALOFT ALSO BECOMES MORE
CONFLUENT AND SOMEWHAT SUBSIDENT IN NATURE...THWARTING DEEP MOIST
CONVECTION...SO STORMS ARE GOING TO STRUGGLE TO FORM AND PERSIST. AS
SUCH...TAILORED POPS DOWN INTO THE SLIGHT CHANCE CATEGORY FOR MOST
OF OUR CWA THIS AFTERNOON AND EVENING...KEEPING HIGHER CHANCES OVER
THE HIGHER TERRAIN OF THE WEST CENTRAL DESERTS IN LA PAZ
COUNTY...AND SOUTH-CENTRAL ARIZONA NORTH AND EAST OF PHOENIX. BY
THURSDAY AFTERNOON...POP CHANCES WILL EVEN BE LESS...WITH STORMS
AGAIN CONFINED TO THE MOUNTAINS NORTH AND EAST OF PHOENIX.

FRIDAY AND SATURDAY...
THE CENTER OF THE UPPER LEVEL ANTICYCLONE WILL POSITION TO OUR
SOUTH..AND ATMOSPHERIC MOISTURE WILL CONTINUE TO THIN OUT...WITH
FORECASTED PRECIPITABLE WATER POTENTIALLY DROPPING TO JUST ABOVE ONE
INCH. THE DRIER AIRMASS WILL SUPPORT WARMER TEMPERATURES FOR THE
LOWER DESERTS...WITH DAYTIME HIGHS FOR YUMA...EL CENTRO AND GILA
BEND AGAIN HITTING THE 110-112 DEGREE RANGE FRIDAY AND SATURDAY.
HOWEVER...THE UPPER LEVEL HIGH STARTS TO REBOUND OVER THE WEEKEND...
592DM 500MB HEIGHTS CENTERING ALONG THE AZ/NM BORDER...SO SOME
MOISTURE RETURN TO THE DESERT SOUTHWEST IS POSSIBLE. THIS MIGHT
OFFSET THE PROJECTED HOT TEMPERATURE FORECAST FOR THESE DAYS BY A
FEW DEGREES. OVER THE LAST NORMAL PERIOD 1981-2010...THE AVERAGE
LAST 110F DAY IN PHOENIX FALLS ON AUGUST 26TH...AND SEPTEMBER 6TH
FOR YUMA. WE COULD CERTAINLY PUSH PAST THE AVERAGE LAST DAY IN THE
PHOENIX AREA BY THE WEEKEND...AND WORK TO CINCH THE TOP SPOT FOR THE
WARMEST AUGUST ON RECORD AT BOTH LOCALES TO CLOSE OUT THE MONTH.

SUNDAY INTO TUESDAY...
A STRONG EASTERN PACIFIC UPPER LEVEL TROUGH APPROACHES THE PACIFIC
NORTHWEST AND NORTHERN CALIFORNIA COAST.  STARTING LATE IN THE
WEEKEND...THE TROUGH BEGINS TO ENCROACH ON AND BREAK DOWN THE RIDGE
PATTERN OVER THE INTERMOUNTAIN WEST. WITH THE TREND FOR LOWER
HEIGHTS NOTED IN THE MODELS/ENSEMBLE SOLUTIONS... TEMPERATURES IN
THE EXTENDED WERE SUBTLY COOLED SUNDAY INTO EARLY NEXT WEEK WITH
MOSTLY BELOW NORMAL POPS ACROSS THE REGION.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...

NO SIGNIFICANT DISTURBANCES MOVING AROUND THE UPPER HIGH AND THROUGH
THE FOW ALOFT...FLOW ALOFT SHIFTING MORE TOWARDS THE SOUTHWEST AND
CONFLUENCE ALOFT ALL POINT TO A REDUCED CHANCE FOR CONVECTION TODAY
OVER THE CENTRAL DESERTS. MOISTURE VALUES REMAIN ELEVATED SO CHANCES
FOR STORMS TODAY ARE NOT ZERO...BUT THEY ARE ONLY SLIGHT CHANCES AND
AS SUCH CONFIDENCE IN STORM DEVELOPMENT OR TIMING IS TOO LOW TO
MERIT ANY MENTION IN THE TAFS DURING THE 12Z PACKAGE. THUS EXPECT
MAINLY SCATTERED MID/HI LEVEL DECKS THIS MORNING WITH SOME HIGH
BASED CUMULUS DEVELOPING THIS AFTERNOON. BROKEN MID/HIGH LEVEL
DEBRIS DECKS OVERNIGHT TONIGHT ARE A BETTER BET AT THE TERMINALS AS
COMPARED TO ANY STORM ACTIVITY. WINDS TO BE RELATIVELY DIURNAL NEXT
24 HOURS AND NOT OVERLY STRONG...BUT SHOULD STORMS FORM NEAR THE
TERMINALS WINDS WOULD CERTAINLY BECOME MUCH STRONGER AND SHIFTY.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...

LOW LEVEL MOISTURE REMAINS ELEVATED BUT OVERALL CHANCES FOR STORMS
NEXT 24 HOURS ARE SLIGHT AT BEST SO CONFIDENCE TOO LOW TO MERIT ANY
MENTION IN THE TAFS. EXPECT FEW-SCT MID/HI DECKS NEXT 24 HOURS WITH
SOME AFTERNOON/EVE CUMULUS POSSIBLE. WINDS WILL STAY RATHER LIGHT
AND FAVOR THE SOUTH/SOUTHEAST AT BOTH KIPL AND KBLH THROUGH THE
AFTERNOON BECOMING MORE SOUTHWESTERLY BY THIS EVENING.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
FRIDAY THROUGH TUESDAY...
DRIER AND WARMER WEATHER WILL SPREAD INTO REGION FROM THE
WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND EVENING TSTMS IS
STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY.
HIGH TEMPERATURES THROUGH SUNDAY WILL BE WELL ABOVE NORMAL WITH
HOTTER DESERTS IN EXCESS OF 110...WITH SOME COOLING BACK TOWARD
NORMAL EARLY NEXT WEEK. MINIMUM RELATIVE HUMIDITIES WILL FALL INTO
THE 10 TO 15 PERCENT RANGE OVER THE WESTERN DESERTS BUT STAY MOSTLY
ABOVE 15 PERCENT ACROSS SOUTH CENTRAL ARIZONA EACH DAY WITH VALUES
REACHING 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST
WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT RECOVERY IS
EXPECTED.

&&

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.WINDS BECOMING VRB 25-35 KTS
IN VCNTY TSTMS. OTHERWISE

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...MEYERS
AVIATION...CB
FIRE WEATHER...VASQUEZ/CB





000
FXUS65 KPSR 261043
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
338 AM MST WED AUG 26 2015

.SYNOPSIS...

HIGH PRESSURE HAS BECOME REESTABLISHED TO THE EAST OF ARIZONA AND
MOIST MONSOONAL FLOW HAS SETTLED INTO THE REGION. THESE CONDITIONS
WILL STILL SUPPORT CONTINUED SLIGHT RAIN CHANCES TODAY ACROSS THE
LOWER DESERTS. DRIER CONDITIONS WILL GRADUALLY RETURN THURSDAY
THROUGH THE END OF THE WEEK ALONG WITH MUCH WARMER ABOVE NORMAL
TEMPERATURES.

&&

.DISCUSSION...
TODAY AND THURSDAY...
REGIONAL UPPER AIR PLOTS/SATELLITE IMAGERY SHOW THE UPPER LEVEL
RIDGE CURRENTLY CENTERED OVER COLORADO/NEW MEXICO THIS MORNING...
THE BROAD ANTICYCLONIC FLOW ALLOWING A CONSIDERABLE AMOUNT OF DEBRIS
CLOUDINESS FROM YESTERDAYS CONVECTION TO STREAM NORTHWARD OVER THE
REGION. A WEAK UPPER LEVEL DISTURBANCE IS ALSO NOTED IN THE WATER
VAPOR IMAGERY CENTERED OVER THE LOWER COLORADO RIVER NORTH OF
BLYTHE. THE GFS/ECMWF/NAM12 ALL INDICATE THAT THIS WEAK LOW WILL GET
PICKED UP IN THE ANTICYCLONIC FLOW AND RIDE OVER THE TOP OF THE
RIDGE INTO UTAH AND WYOMING LATER TODAY. BY THURSDAY MORNING...THE
LOW MOVES OFF TO THE LEE SIDE OF THE ROCKIES AND STRENGTHENS...
THEREBY SUPPRESSING THE RIDGE TO THE SOUTH WHERE IT WILL FINALLY
SETTLES A 595DM 500MB CENTER OVER SOUTHEAST AZ/SOUTHWEST NM THURSDAY
AFTERNOON.

THIS RATHER HASTY MODIFICATION AND REPOSITIONING OF THE UPPER LEVEL
RIDGE AXIS WILL QUICKLY RESULT IN A TRANSITION TO A DRIER
SOUTHWESTERLY FLOW ALOFT...EFFECTIVELY DRYING OUT THE ATMOSPHERE.
THIS GRADUAL DOWNWARD TREND OF MOISTURE AND MIXING RATIOS TO LESS
THAN 10G/KG WILL EFFECTIVELY KNOCK DOWN PRECIPITATION CHANCES...
ESPECIALLY OVER THE LOWER DESERTS. EVEN THOUGH PLENTIFUL MOISTURE
WILL LINGER FOR A DAY OR TWO...THE FLOW ALOFT ALSO BECOMES MORE
CONFLUENT AND SOMEWHAT SUBSIDENT IN NATURE...THWARTING DEEP MOIST
CONVECTION...SO STORMS ARE GOING TO STRUGGLE TO FORM AND PERSIST. AS
SUCH...TAILORED POPS DOWN INTO THE SLIGHT CHANCE CATEGORY FOR MOST
OF OUR CWA THIS AFTERNOON AND EVENING...KEEPING HIGHER CHANCES OVER
THE HIGHER TERRAIN OF THE WEST CENTRAL DESERTS IN LA PAZ
COUNTY...AND SOUTH-CENTRAL ARIZONA NORTH AND EAST OF PHOENIX. BY
THURSDAY AFTERNOON...POP CHANCES WILL EVEN BE LESS...WITH STORMS
AGAIN CONFINED TO THE MOUNTAINS NORTH AND EAST OF PHOENIX.

FRIDAY AND SATURDAY...
THE CENTER OF THE UPPER LEVEL ANTICYCLONE WILL POSITION TO OUR
SOUTH..AND ATMOSPHERIC MOISTURE WILL CONTINUE TO THIN OUT...WITH
FORECASTED PRECIPITABLE WATER POTENTIALLY DROPPING TO JUST ABOVE ONE
INCH. THE DRIER AIRMASS WILL SUPPORT WARMER TEMPERATURES FOR THE
LOWER DESERTS...WITH DAYTIME HIGHS FOR YUMA...EL CENTRO AND GILA
BEND AGAIN HITTING THE 110-112 DEGREE RANGE FRIDAY AND SATURDAY.
HOWEVER...THE UPPER LEVEL HIGH STARTS TO REBOUND OVER THE WEEKEND...
592DM 500MB HEIGHTS CENTERING ALONG THE AZ/NM BORDER...SO SOME
MOISTURE RETURN TO THE DESERT SOUTHWEST IS POSSIBLE. THIS MIGHT
OFFSET THE PROJECTED HOT TEMPERATURE FORECAST FOR THESE DAYS BY A
FEW DEGREES. OVER THE LAST NORMAL PERIOD 1981-2010...THE AVERAGE
LAST 110F DAY IN PHOENIX FALLS ON AUGUST 26TH...AND SEPTEMBER 6TH
FOR YUMA. WE COULD CERTAINLY PUSH PAST THE AVERAGE LAST DAY IN THE
PHOENIX AREA BY THE WEEKEND...AND WORK TO CINCH THE TOP SPOT FOR THE
WARMEST AUGUST ON RECORD AT BOTH LOCALES TO CLOSE OUT THE MONTH.

SUNDAY INTO TUESDAY...
A STRONG EASTERN PACIFIC UPPER LEVEL TROUGH APPROACHES THE PACIFIC
NORTHWEST AND NORTHERN CALIFORNIA COAST.  STARTING LATE IN THE
WEEKEND...THE TROUGH BEGINS TO ENCROACH ON AND BREAK DOWN THE RIDGE
PATTERN OVER THE INTERMOUNTAIN WEST. WITH THE TREND FOR LOWER
HEIGHTS NOTED IN THE MODELS/ENSEMBLE SOLUTIONS... TEMPERATURES IN
THE EXTENDED WERE SUBTLY COOLED SUNDAY INTO EARLY NEXT WEEK WITH
MOSTLY BELOW NORMAL POPS ACROSS THE REGION.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
BKN-OVC MID-HIGH LEVEL CLOUD LAYERS TO BECOME SCT-BKN BY WED MORNING
WITH CLOUD BASES MAINLY AOA 8K FEET. LIGHT SOUTHEASTERLY WINDS TO
CONTINUE THROUGH MIDDAY WEDNESDAY BEFORE BECOMING WESTERLY BY
WEDNESDAY AFTERNOON. ALTHOUGH THERE IS A REMOTE CHANCE THAT
THUNDERSTORM WILL ONCE AGAIN AFFECT ONE OR MORE OF THE PHX AREA
TERMINALS...THE CONFIDENCE LEVEL IS FAR TOO LOW TO INCLUDE TS IN THE
TAFS AT THIS TIME. HOWEVER...THERE IS MUCH BETTER CONFIDENCE THAT
OUTFLOWS FROM DISTANT THUNDERSTORMS WILL MOVE INTO THE PHX AREA WED
EVENING...WITH THIS SCENARIO BEING REFLECTED IN THE CURRENTS TAFS.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
SCT-BKN MID-HIGH LEVEL CLOUD LAYERS TO PREVAIL THROUGH THE TAF
PERIOD AT BOTH SE CA TERMINALS. WINDS TO REMAIN MAINLY ON THE LIGHT
SIDE...AOB 8 KTS...MAINLY FOLLOWING TYPICAL DIURNAL TRENDS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
FRIDAY THROUGH TUESDAY...
DRIER AND WARMER WEATHER WILL SPREAD INTO REGION FROM THE
WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND EVENING TSTMS IS
STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY.
MINIMUM RELATIVE HUMIDITIES WILL FALL INTO THE 14 TO 18 PERCENT
RANGE...BUT NEAR 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.

&&

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.WINDS BECOMING VRB 25-35 KTS
IN VCNTY TSTMS. OTHERWISE

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...MEYERS
AVIATION...PERCHA
FIRE WEATHER...VASQUEZ




000
FXUS65 KPSR 261043
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
338 AM MST WED AUG 26 2015

.SYNOPSIS...

HIGH PRESSURE HAS BECOME REESTABLISHED TO THE EAST OF ARIZONA AND
MOIST MONSOONAL FLOW HAS SETTLED INTO THE REGION. THESE CONDITIONS
WILL STILL SUPPORT CONTINUED SLIGHT RAIN CHANCES TODAY ACROSS THE
LOWER DESERTS. DRIER CONDITIONS WILL GRADUALLY RETURN THURSDAY
THROUGH THE END OF THE WEEK ALONG WITH MUCH WARMER ABOVE NORMAL
TEMPERATURES.

&&

.DISCUSSION...
TODAY AND THURSDAY...
REGIONAL UPPER AIR PLOTS/SATELLITE IMAGERY SHOW THE UPPER LEVEL
RIDGE CURRENTLY CENTERED OVER COLORADO/NEW MEXICO THIS MORNING...
THE BROAD ANTICYCLONIC FLOW ALLOWING A CONSIDERABLE AMOUNT OF DEBRIS
CLOUDINESS FROM YESTERDAYS CONVECTION TO STREAM NORTHWARD OVER THE
REGION. A WEAK UPPER LEVEL DISTURBANCE IS ALSO NOTED IN THE WATER
VAPOR IMAGERY CENTERED OVER THE LOWER COLORADO RIVER NORTH OF
BLYTHE. THE GFS/ECMWF/NAM12 ALL INDICATE THAT THIS WEAK LOW WILL GET
PICKED UP IN THE ANTICYCLONIC FLOW AND RIDE OVER THE TOP OF THE
RIDGE INTO UTAH AND WYOMING LATER TODAY. BY THURSDAY MORNING...THE
LOW MOVES OFF TO THE LEE SIDE OF THE ROCKIES AND STRENGTHENS...
THEREBY SUPPRESSING THE RIDGE TO THE SOUTH WHERE IT WILL FINALLY
SETTLES A 595DM 500MB CENTER OVER SOUTHEAST AZ/SOUTHWEST NM THURSDAY
AFTERNOON.

THIS RATHER HASTY MODIFICATION AND REPOSITIONING OF THE UPPER LEVEL
RIDGE AXIS WILL QUICKLY RESULT IN A TRANSITION TO A DRIER
SOUTHWESTERLY FLOW ALOFT...EFFECTIVELY DRYING OUT THE ATMOSPHERE.
THIS GRADUAL DOWNWARD TREND OF MOISTURE AND MIXING RATIOS TO LESS
THAN 10G/KG WILL EFFECTIVELY KNOCK DOWN PRECIPITATION CHANCES...
ESPECIALLY OVER THE LOWER DESERTS. EVEN THOUGH PLENTIFUL MOISTURE
WILL LINGER FOR A DAY OR TWO...THE FLOW ALOFT ALSO BECOMES MORE
CONFLUENT AND SOMEWHAT SUBSIDENT IN NATURE...THWARTING DEEP MOIST
CONVECTION...SO STORMS ARE GOING TO STRUGGLE TO FORM AND PERSIST. AS
SUCH...TAILORED POPS DOWN INTO THE SLIGHT CHANCE CATEGORY FOR MOST
OF OUR CWA THIS AFTERNOON AND EVENING...KEEPING HIGHER CHANCES OVER
THE HIGHER TERRAIN OF THE WEST CENTRAL DESERTS IN LA PAZ
COUNTY...AND SOUTH-CENTRAL ARIZONA NORTH AND EAST OF PHOENIX. BY
THURSDAY AFTERNOON...POP CHANCES WILL EVEN BE LESS...WITH STORMS
AGAIN CONFINED TO THE MOUNTAINS NORTH AND EAST OF PHOENIX.

FRIDAY AND SATURDAY...
THE CENTER OF THE UPPER LEVEL ANTICYCLONE WILL POSITION TO OUR
SOUTH..AND ATMOSPHERIC MOISTURE WILL CONTINUE TO THIN OUT...WITH
FORECASTED PRECIPITABLE WATER POTENTIALLY DROPPING TO JUST ABOVE ONE
INCH. THE DRIER AIRMASS WILL SUPPORT WARMER TEMPERATURES FOR THE
LOWER DESERTS...WITH DAYTIME HIGHS FOR YUMA...EL CENTRO AND GILA
BEND AGAIN HITTING THE 110-112 DEGREE RANGE FRIDAY AND SATURDAY.
HOWEVER...THE UPPER LEVEL HIGH STARTS TO REBOUND OVER THE WEEKEND...
592DM 500MB HEIGHTS CENTERING ALONG THE AZ/NM BORDER...SO SOME
MOISTURE RETURN TO THE DESERT SOUTHWEST IS POSSIBLE. THIS MIGHT
OFFSET THE PROJECTED HOT TEMPERATURE FORECAST FOR THESE DAYS BY A
FEW DEGREES. OVER THE LAST NORMAL PERIOD 1981-2010...THE AVERAGE
LAST 110F DAY IN PHOENIX FALLS ON AUGUST 26TH...AND SEPTEMBER 6TH
FOR YUMA. WE COULD CERTAINLY PUSH PAST THE AVERAGE LAST DAY IN THE
PHOENIX AREA BY THE WEEKEND...AND WORK TO CINCH THE TOP SPOT FOR THE
WARMEST AUGUST ON RECORD AT BOTH LOCALES TO CLOSE OUT THE MONTH.

SUNDAY INTO TUESDAY...
A STRONG EASTERN PACIFIC UPPER LEVEL TROUGH APPROACHES THE PACIFIC
NORTHWEST AND NORTHERN CALIFORNIA COAST.  STARTING LATE IN THE
WEEKEND...THE TROUGH BEGINS TO ENCROACH ON AND BREAK DOWN THE RIDGE
PATTERN OVER THE INTERMOUNTAIN WEST. WITH THE TREND FOR LOWER
HEIGHTS NOTED IN THE MODELS/ENSEMBLE SOLUTIONS... TEMPERATURES IN
THE EXTENDED WERE SUBTLY COOLED SUNDAY INTO EARLY NEXT WEEK WITH
MOSTLY BELOW NORMAL POPS ACROSS THE REGION.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
BKN-OVC MID-HIGH LEVEL CLOUD LAYERS TO BECOME SCT-BKN BY WED MORNING
WITH CLOUD BASES MAINLY AOA 8K FEET. LIGHT SOUTHEASTERLY WINDS TO
CONTINUE THROUGH MIDDAY WEDNESDAY BEFORE BECOMING WESTERLY BY
WEDNESDAY AFTERNOON. ALTHOUGH THERE IS A REMOTE CHANCE THAT
THUNDERSTORM WILL ONCE AGAIN AFFECT ONE OR MORE OF THE PHX AREA
TERMINALS...THE CONFIDENCE LEVEL IS FAR TOO LOW TO INCLUDE TS IN THE
TAFS AT THIS TIME. HOWEVER...THERE IS MUCH BETTER CONFIDENCE THAT
OUTFLOWS FROM DISTANT THUNDERSTORMS WILL MOVE INTO THE PHX AREA WED
EVENING...WITH THIS SCENARIO BEING REFLECTED IN THE CURRENTS TAFS.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
SCT-BKN MID-HIGH LEVEL CLOUD LAYERS TO PREVAIL THROUGH THE TAF
PERIOD AT BOTH SE CA TERMINALS. WINDS TO REMAIN MAINLY ON THE LIGHT
SIDE...AOB 8 KTS...MAINLY FOLLOWING TYPICAL DIURNAL TRENDS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
FRIDAY THROUGH TUESDAY...
DRIER AND WARMER WEATHER WILL SPREAD INTO REGION FROM THE
WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND EVENING TSTMS IS
STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY.
MINIMUM RELATIVE HUMIDITIES WILL FALL INTO THE 14 TO 18 PERCENT
RANGE...BUT NEAR 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.

&&

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.WINDS BECOMING VRB 25-35 KTS
IN VCNTY TSTMS. OTHERWISE

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...MEYERS
AVIATION...PERCHA
FIRE WEATHER...VASQUEZ





000
FXUS65 KPSR 261043
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
338 AM MST WED AUG 26 2015

.SYNOPSIS...

HIGH PRESSURE HAS BECOME REESTABLISHED TO THE EAST OF ARIZONA AND
MOIST MONSOONAL FLOW HAS SETTLED INTO THE REGION. THESE CONDITIONS
WILL STILL SUPPORT CONTINUED SLIGHT RAIN CHANCES TODAY ACROSS THE
LOWER DESERTS. DRIER CONDITIONS WILL GRADUALLY RETURN THURSDAY
THROUGH THE END OF THE WEEK ALONG WITH MUCH WARMER ABOVE NORMAL
TEMPERATURES.

&&

.DISCUSSION...
TODAY AND THURSDAY...
REGIONAL UPPER AIR PLOTS/SATELLITE IMAGERY SHOW THE UPPER LEVEL
RIDGE CURRENTLY CENTERED OVER COLORADO/NEW MEXICO THIS MORNING...
THE BROAD ANTICYCLONIC FLOW ALLOWING A CONSIDERABLE AMOUNT OF DEBRIS
CLOUDINESS FROM YESTERDAYS CONVECTION TO STREAM NORTHWARD OVER THE
REGION. A WEAK UPPER LEVEL DISTURBANCE IS ALSO NOTED IN THE WATER
VAPOR IMAGERY CENTERED OVER THE LOWER COLORADO RIVER NORTH OF
BLYTHE. THE GFS/ECMWF/NAM12 ALL INDICATE THAT THIS WEAK LOW WILL GET
PICKED UP IN THE ANTICYCLONIC FLOW AND RIDE OVER THE TOP OF THE
RIDGE INTO UTAH AND WYOMING LATER TODAY. BY THURSDAY MORNING...THE
LOW MOVES OFF TO THE LEE SIDE OF THE ROCKIES AND STRENGTHENS...
THEREBY SUPPRESSING THE RIDGE TO THE SOUTH WHERE IT WILL FINALLY
SETTLES A 595DM 500MB CENTER OVER SOUTHEAST AZ/SOUTHWEST NM THURSDAY
AFTERNOON.

THIS RATHER HASTY MODIFICATION AND REPOSITIONING OF THE UPPER LEVEL
RIDGE AXIS WILL QUICKLY RESULT IN A TRANSITION TO A DRIER
SOUTHWESTERLY FLOW ALOFT...EFFECTIVELY DRYING OUT THE ATMOSPHERE.
THIS GRADUAL DOWNWARD TREND OF MOISTURE AND MIXING RATIOS TO LESS
THAN 10G/KG WILL EFFECTIVELY KNOCK DOWN PRECIPITATION CHANCES...
ESPECIALLY OVER THE LOWER DESERTS. EVEN THOUGH PLENTIFUL MOISTURE
WILL LINGER FOR A DAY OR TWO...THE FLOW ALOFT ALSO BECOMES MORE
CONFLUENT AND SOMEWHAT SUBSIDENT IN NATURE...THWARTING DEEP MOIST
CONVECTION...SO STORMS ARE GOING TO STRUGGLE TO FORM AND PERSIST. AS
SUCH...TAILORED POPS DOWN INTO THE SLIGHT CHANCE CATEGORY FOR MOST
OF OUR CWA THIS AFTERNOON AND EVENING...KEEPING HIGHER CHANCES OVER
THE HIGHER TERRAIN OF THE WEST CENTRAL DESERTS IN LA PAZ
COUNTY...AND SOUTH-CENTRAL ARIZONA NORTH AND EAST OF PHOENIX. BY
THURSDAY AFTERNOON...POP CHANCES WILL EVEN BE LESS...WITH STORMS
AGAIN CONFINED TO THE MOUNTAINS NORTH AND EAST OF PHOENIX.

FRIDAY AND SATURDAY...
THE CENTER OF THE UPPER LEVEL ANTICYCLONE WILL POSITION TO OUR
SOUTH..AND ATMOSPHERIC MOISTURE WILL CONTINUE TO THIN OUT...WITH
FORECASTED PRECIPITABLE WATER POTENTIALLY DROPPING TO JUST ABOVE ONE
INCH. THE DRIER AIRMASS WILL SUPPORT WARMER TEMPERATURES FOR THE
LOWER DESERTS...WITH DAYTIME HIGHS FOR YUMA...EL CENTRO AND GILA
BEND AGAIN HITTING THE 110-112 DEGREE RANGE FRIDAY AND SATURDAY.
HOWEVER...THE UPPER LEVEL HIGH STARTS TO REBOUND OVER THE WEEKEND...
592DM 500MB HEIGHTS CENTERING ALONG THE AZ/NM BORDER...SO SOME
MOISTURE RETURN TO THE DESERT SOUTHWEST IS POSSIBLE. THIS MIGHT
OFFSET THE PROJECTED HOT TEMPERATURE FORECAST FOR THESE DAYS BY A
FEW DEGREES. OVER THE LAST NORMAL PERIOD 1981-2010...THE AVERAGE
LAST 110F DAY IN PHOENIX FALLS ON AUGUST 26TH...AND SEPTEMBER 6TH
FOR YUMA. WE COULD CERTAINLY PUSH PAST THE AVERAGE LAST DAY IN THE
PHOENIX AREA BY THE WEEKEND...AND WORK TO CINCH THE TOP SPOT FOR THE
WARMEST AUGUST ON RECORD AT BOTH LOCALES TO CLOSE OUT THE MONTH.

SUNDAY INTO TUESDAY...
A STRONG EASTERN PACIFIC UPPER LEVEL TROUGH APPROACHES THE PACIFIC
NORTHWEST AND NORTHERN CALIFORNIA COAST.  STARTING LATE IN THE
WEEKEND...THE TROUGH BEGINS TO ENCROACH ON AND BREAK DOWN THE RIDGE
PATTERN OVER THE INTERMOUNTAIN WEST. WITH THE TREND FOR LOWER
HEIGHTS NOTED IN THE MODELS/ENSEMBLE SOLUTIONS... TEMPERATURES IN
THE EXTENDED WERE SUBTLY COOLED SUNDAY INTO EARLY NEXT WEEK WITH
MOSTLY BELOW NORMAL POPS ACROSS THE REGION.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
BKN-OVC MID-HIGH LEVEL CLOUD LAYERS TO BECOME SCT-BKN BY WED MORNING
WITH CLOUD BASES MAINLY AOA 8K FEET. LIGHT SOUTHEASTERLY WINDS TO
CONTINUE THROUGH MIDDAY WEDNESDAY BEFORE BECOMING WESTERLY BY
WEDNESDAY AFTERNOON. ALTHOUGH THERE IS A REMOTE CHANCE THAT
THUNDERSTORM WILL ONCE AGAIN AFFECT ONE OR MORE OF THE PHX AREA
TERMINALS...THE CONFIDENCE LEVEL IS FAR TOO LOW TO INCLUDE TS IN THE
TAFS AT THIS TIME. HOWEVER...THERE IS MUCH BETTER CONFIDENCE THAT
OUTFLOWS FROM DISTANT THUNDERSTORMS WILL MOVE INTO THE PHX AREA WED
EVENING...WITH THIS SCENARIO BEING REFLECTED IN THE CURRENTS TAFS.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
SCT-BKN MID-HIGH LEVEL CLOUD LAYERS TO PREVAIL THROUGH THE TAF
PERIOD AT BOTH SE CA TERMINALS. WINDS TO REMAIN MAINLY ON THE LIGHT
SIDE...AOB 8 KTS...MAINLY FOLLOWING TYPICAL DIURNAL TRENDS.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
FRIDAY THROUGH TUESDAY...
DRIER AND WARMER WEATHER WILL SPREAD INTO REGION FROM THE
WEST...HOWEVER A SLIGHT CHANCE OF AFTERNOON AND EVENING TSTMS IS
STILL FORECAST FOR THE MOUNTAINS OF SOUTHERN GILA COUNTY EACH DAY.
MINIMUM RELATIVE HUMIDITIES WILL FALL INTO THE 14 TO 18 PERCENT
RANGE...BUT NEAR 25 PERCENT IN SOUTHERN GILA COUNTY. AFTERNOON
SOUTHWEST WINDS WILL RANGE FROM 10 TO 20 MPH. GOOD OVERNIGHT
RECOVERY IS EXPECTED.

&&

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.WINDS BECOMING VRB 25-35 KTS
IN VCNTY TSTMS. OTHERWISE

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX

DISCUSSION...MEYERS
AVIATION...PERCHA
FIRE WEATHER...VASQUEZ




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