Special Weather Statement, NWS Phoenix, AZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
912 PM MST SUN JUL 27 2014

.SYNOPSIS...
A RELATIVELY ACTIVE MONSOON PATTERN WILL LAST THROUGH MONDAY AS A
SERIES OF DISTURBANCES MOVE NORTHWARD THROUGH SOUTHERN ARIZONA AND
SOUTHEAST CA...INCREASING THE THREAT FOR THUNDERSTORMS ACROSS THE
REGION. MONSOON MOISTURE WILL LIKELY REMAIN ACROSS THE REGION
THROUGH THE EARLY PART OF THIS WEEK...WITH A CHANCE FOR AFTERNOON
AND EVENING SHOWERS AND THUNDERSTORMS EACH DAY. SOME REDUCTION IN
MONSOON ACTIVITY IS POSSIBLE BY THE MIDDLE OF THE WEEK AS WESTERLY
FLOW ALOFT BRINGS SOMEWHAT DRIER AIR INTO THE REGION.

&&

.DISCUSSION...
A RATHER COMPLEX WEATHER PICTURE EXISTS ACROSS THE REGION THIS
EVENING WITH TWO STRONG MID-LEVEL CIRCULATIONS AFFECTING MONSOON
ACTIVITY. WATER VAPOR IMAGERY HAS SHOWN ONE CIRCULATION MOVING
NORTHWARD ACROSS THE BAJA PENINSULA WITH LITTLE TO NO ACTIVE STORMS
ASSOCIATED WITH THE FEATURE. THE OTHER MORE COMPACT CIRCULATION
MOVED THROUGH SOUTHEAST ARIZONA AND SOUTHWEST NEW MEXICO THIS
AFTERNOON AND CONTINUES TO PROGRESS TO THE NORTH NORTHWEST ALONG THE
ARIZONA/NEW MEXICO STATE LINE. THIS FEATURE PROMPTED SEVERAL
CLUSTERS OF THUNDERSTORMS...BUT MOST HAVE JUST CLIPPED OUR FAR
EASTERN ZONES. IN BETWEEN THESE FEATURES...AN AREA OF SUBSIDENCE HAS
SUPPRESSED ANY STORM DEVELOPMENT ACROSS FROM THE LOWER COLORADO
RIVER VALLEY THROUGH MUCH OF SOUTH-CENTRAL ARIZONA. CURRENT RADAR
IMAGERY SHOWS ANOTHER CLUSTER OF SHOWERS AND THUNDERSTORMS TRACKING
NORTH NORTHWEST ACROSS SOUTHEAST ARIZONA.

00Z PHOENIX RAOB WAS NOT TOO PROMISING TO ALLOW FOR STORMS TO
PROPAGATE THROUGH MUCH OF THE LOWER DESERTS...BUT THE TUCSON RAOB
SHOWED MUCH MORE  INSTABILITY...ESPECIALLY IN THE MID LEVELS. THE
WAY THE CLUSTER OF STORMS HAS BEEN PROPAGATING OVER THE PAST COUPLE
HOURS...THE COLD POOL DOESN/T SEEM TO BE IMPRESSIVELY STRONG...SO
OUTFLOWS ARE NOT OVERLY ROBUST AND FURTHER STORM DEVELOPMENT ALONG
OUTFLOWS HAS BEEN LIMITED. EXPECT THESE SHOWERS AND STORMS TO
CONTINUE NORTHWESTWARD INTO THE EASTERN PHOENIX AREA LATE THIS
EVENING WITH THE POSSIBILITY OF SOME STRONG GUSTY WINDS. HAVE
DRAMATICALLY TRIMMED POPS FOR LATE THIS EVENING AND THE OVERNIGHT
PERIOD FROM PHOENIX WESTWARD...BUT HAVE KEPT AT LEAST SLIGHT CHANCE
POPS AREAWIDE.

DECENT MOISTURE WILL REMAIN IN THE AREA THROUGH MONDAY WITH
CONTINUED STORM CHANCES...BUT MODELS INDICATE A DRYING WESTERLY FLOW
WILL SET UP STARTING TUESDAY. TUESDAY MAY BE A BIT OF A TRANSITION
DAY WITH STORMS MAINLY FOCUSED ACROSS HIGHER TERRAIN AREAS...BUT
CAN/T RULE OUT A FEW STORMS ACROSS THE LOWER DESERTS. LATEST MODEL
RUNS HAVE DEFINITELY BEEN TRENDING TOWARD A SOMEWHAT DRIER MID WEEK
PERIOD WITH 1000-700MB MIXING RATIOS DROPPING INTO THE 6-8 G/KG
RANGE AND PWATS DROPPING TO BETWEEN 1.0 AND 1.5 INCHES. AT THIS
MOMENT...IT LOOKS LIKE ANY MONSOON ACTIVITY FOR WEDNESDAY AND
THURSDAY WILL LIKELY BE CONFINED TO FAR EASTERN ARIZONA. MODELS THEN
POINT TOWARD A BIT OF MOISTURE RESURGENCE FOR FRIDAY INTO NEXT
SATURDAY.

TEMPERATURES FOR THE PERIOD SHOULD FALL WITHIN A SMALL TEMPERATURE
RANGE OF RIGHT AROUND SEASONAL NORMALS. SOME AREAS MAY APPROACH THE
110 DEGREE MARK FOR HIGHS ON WEDNESDAY AND THURSDAY AS DRIER AIR
ALLOWS FOR A BUMP IN TEMPERATURES.

&&

.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
SHOWERS AND STORMS OVER THE HIGHER TERRAIN EAST AND SOUTHEAST OF
PHOENIX IS EXPECTED TO PROPAGATE TOWARDS KPHX-KIWA-KSDL THROUGH LATE
THIS EVENING. STORM OUTFLOWS SHOULD SWITCH WINDS TO AN EASTERLY
DIRECTION BETWEEN 05-07Z...WITH A MODEST GUSTY WIND POTENTIAL. SOME
ISOLATED TO SCATTERED SHOWERS AND STORMS SHOULD MAKE THEIR WAY INTO
THE PHOENIX AREA...BUT COVERAGE SHOULD BE LIMITED ENOUGH TO NOT
MENTION IN KPHX AND KSDL TAFS.

SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
MOSTLY CLEAR SKIES EXPECTED AT LEAST INTO THE EARLY OVERNIGHT WITH A
RELATIVELY LOW THUNDERSTORM CHANCE STARTING LATE TONIGHT INTO MONDAY
MORNING. BACKGROUND WINDS WILL REMAIN LIGHT THROUGH THE PERIOD...BUT
A SMALL CHANCE OF STORM OUTFLOWS AND GUSTY WINDS ARE POSSIBLE WITH
ANY STORMS THAT DEVELOP TONIGHT INTO MONDAY.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
NEAR NORMAL TEMPERATURES AND HIGHER RELATIVE HUMIDITY LEVELS ARE
EXPECTED. MINIMUM RELATIVE HUMIDITY LEVELS WILL RANGE FROM 15 TO 25
PERCENT AND RECOVER OVERNIGHT TO 35 TO 45 PERCENT. THERE WILL BE A
DAILY THREAT OF AFTERNOON AND EVENING THUNDERSTORMS...BUT THESE WILL
BE MAINLY CONFINED TO THE HIGHER TERRAIN OF SOUTH-CENTRAL ARIZONA.
WINDS WILL BE GENERALLY LESS THAN 15 MPH...EXCEPT IN THE VICINITY OF
THUNDERSTORMS.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...

AZ...NONE.

CA...NONE.

&&

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

DISCUSSION...KUHLMAN
AVIATION...KUHLMAN
FIRE WEATHER...HIRSCH/MCLANE

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE PHOENIX AZ
250 PM MST SUN JUL 27 2014

AZZ020>028-CAZ030>033-282200-
LOWER COLORADO RIVER VALLEY AZ-WEST CENTRAL DESERTS-
NORTHWEST MARICOPA COUNTY-GREATER PHOENIX AREA-
SOUTHERN GILA COUNTY/TONTO NATIONAL FOREST FOOTHILLS-
YUMA/MARTINEZ LAKE AND VICINITY-SOUTHWEST DESERTS-
SOUTHWEST MARICOPA COUNTY-NORTHWEST AND NORTH CENTRAL PINAL COUNTY-
JOSHUA TREE NATIONAL PARK-LOWER COLORADO RIVER VALLEY CA-
RIVERSIDE COUNTY/EASTERN DESERTS-IMPERIAL COUNTY-
250 PM MST SUN JUL 27 2014 /250 PM PDT SUN JUL 27 2014/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EAST-CENTRAL
ARIZONA...EXTREME SOUTHWEST ARIZONA...EXTREME WEST-CENTRAL
ARIZONA...SOUTH-CENTRAL ARIZONA...SOUTHWEST ARIZONA...WEST-CENTRAL
ARIZONA...EXTREME SOUTHEAST CALIFORNIA AND SOUTHEAST CALIFORNIA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

SCATTERED TO NUMEROUS THUNDERSTORM ARE FORECAST TO DEVELOP TODAY...
AS A WEAK WEATHER DISTURBANCE HELPS TO INCREASE CONVECTIVE ACTIVITY
OVER THE REGION. WHERE THUNDERSTORMS FORM...STRONG GUSTY OUTFLOW
WINDS COULD GENERATE AREAS OF BLOWING DUST CREATING DRIVING AND
HEALTH HAZARDS. SOME STORMS COULD PRODUCE HEAVY RAIN AND LOCALIZED
FLOODING OF ROADWAYS AND PONDING OF WATER IN LOW LYING AREAS.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.

ISOLATED TO SCATTERED THUNDERSTORM ARE FORECAST TO DEVELOP EACH DAY.
WHERE THUNDERSTORMS FORM...STRONG GUSTY OUTFLOW WINDS COULD GENERATE
AREAS OF BLOWING DUST CREATING DRIVING AND HEALTH HAZARDS. SOME
STORMS COULD PRODUCE HEAVY RAIN AND LOCALIZED FLOODING OF ROADWAYS
AND PONDING OF WATER IN LOW LYING AREAS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT

WEATHER.GOV/PHOENIX

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PHOENIX AZ
930 PM MST SUN JUL 27 2014

AZZ024-028-280500-
PINAL AZ-
930 PM MST SUN JUL 27 2014

...SIGNIFICANT WEATHER ADVISORY...

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

SIGNIFICANT WEATHER ADVISORY FOR...
  NORTH CENTRAL PINAL COUNTY IN SOUTH CENTRAL ARIZONA

UNTIL 1000 PM MST

AT 926 PM MST...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED
STRONG OUTFLOW WINDS AHEAD OF AN AREA OF SHOWERS LOCATED 9 MILES
SOUTH OF BOYCE THOMPSON ARBORETUM...MOVING WEST AT 25 MPH.

WIND GUSTS TO 40 MPH AND LOCALLY DENSE BLOWING DUST ARE
POSSIBLE...ESPECIALLY ALONG US 60 BETWEEN FLORENCE JUNCTIONS AND
SUPERIOR.

LOCATIONS IMPACTED INCLUDE...
   BOYCE THOMPSON ARBORETUM...
   QUEEN VALLEY AND  FLORENCE...
   FLORENCE JUNCTION...

LAT...LON 3321 11100 3302 11126 3301 11128 3300 11137
      3323 11142 3334 11132 3326 11098
TIME...MOT...LOC 0429Z 104DEG 21KT 3315 11117

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