Severe Thunderstorm Warning 26, NWS Phoenix, AZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
210 PM MST THU AUG 6 2015

.SYNOPSIS...INCREASED MONSOON MOISTURE WILL LEAD TO A THREAT OF
SHOWERS AND THUNDESTORMS THROUGH EARLY TONIGHT. A MORE STABLE AND
DRIER WESTERLY WIND PATTERN WILL SHIFT STORM CHANCES INTO NORTHERN
AND EASTERN ARIZONA FRIDAY...THEN INTO EASTERN ARIZONA THIS WEEKEND.
THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL SLOWLY RETURN
STATEWIDE EARLY NEXT WEEK.

&&

.DISCUSSION...

REMAINDER OF TODAY AND TONIGHT... THE ATMOSPHERE OVER OUR FORECAST
AREA IS A MESS AND WORTHY OF A BROAD BRUSH FORECAST OF A CHANCE OF
SHOWERS AND THUNDERSTORMS THE REMAINDER OF THE AFTERNOON THROUGH
EARLY TONIGHT. ACCELERATING UPPER LEVEL WINDS FROM A COL AREA OFF
THE BAJA COAST...INCREASING LOW LEVEL MONSOON MOISTURE FROM
MEXICO...AND LATE AFTERNOON WARM SIDE DIFFERENTIAL HEATING MAKE THE
ATMOSPHERE SORT OF MESSY WITH POTENTIAL INSTABILITY AT EVERY TURN.

HOWEVER...IF THUNDERSTORMS DO DEVELOP OVER PORTIONS OF SOUTHEAST CA
AND SOUTHWEST AZ...THERE IS A POSSIBILITY OF STRONG DOWNBURST WINDS
DUE TO HIGH AFTERNOON TEMPERATURES IN THESE LOCATIONS.

SATURDAY AND SUNDAY...A DRIER AND MORE STABLE AIRMASS WILL SPREAD
INTO OUR FORECAST AREA FROM THE WEST THIS WEEKEND...KEEPING THE
CHANCE OF STORMS CONFINED TO EASTERN ARIZONA...EXCEPT FOR A SLIGHT
CHANCE OVER THE HIGHER TERRAIN OF SOUTHERN GILA COUNTY/ZONE 24.

MONDAY THROUGH WEDNESDAY...MODELS CONTINUE TO VARY ON THE TIMING AND
INTENSITY OF INVERTED TROFS MOVING INTO SOUTHERN AZ FRM MEXICO THIS
PERIOD. ONE THING IS FOR CERTAIN...THERE WILL BE PATTERN CHANGE THIS
PERIOD WITH A CONTINUOUS SOUTHERLY FLOW OF MONSOON MOISTURE EVERY
TODAY. THEREFORE SINCE AREAL STORM COVERAGE AND POTENTIAL STORM
INTENSITIES WILL BE UNCERTAIN...THE BEST APPROACH IS TO CONTINUE A
LOW THREAT OF SHOWERS AND THUNDERSTORMS DAY DAY THIS PERIOD.

&&

.AVIATION...

SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
FAIRLY COMPLEX FORECAST SCENARIO SETTING UP FOR THE AREA AS MONSOON
MOISTURE SURGED BACK INTO THE REGION OVERNIGHT. MORNING DEBRIS CLOUD
SHIELD AND STRAY VCSH WILL HOLD OVER THE PHX AREA TERMINALS THROUGH
AT LEAST THE EARLY AFTERNOON. AM CLOUD COVER COULD PREVENT OR
AT LEAST DELAY STORM DEVELOPMENT DUE TO HEATING FROM THE SUN OVER THE
SOUTH-CENTRAL AZ THIS AFTN. MORE LIKELY SCENARIO FOR STORM
DEVELOPMENT COULD BE FROM LONG TRAVELING AND INTERSECTING OUTFLOWS
LATER INTO THE AFTN AND EVENING HOURS. DID INTRODUCE VCTS MENTION
FOR THE PHX AREA TERMINALS POST 07/02Z. WITH THE MOISTURE RETURN AND
FAVORABLE ENVIRONMENT FOR STORMS TODAY...COULD NOT RULE OUT SOME
MENTION. MIDDAY SE TO VRB WINDS WILL GRADUALLY TRANSITION TO SW-W
HEADINGS BY THE AFTERNOON.

SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
FAVORABLE MOISTURE RETURN AND STORM DYNAMIC SET-UP THIS AFTN AND
EVENING...WITH AT LEAST PLENTY OF CB COVERAGE ACROSS SE CA BY THE
AFTN. MAINTAINED VCTS IN FOR KBLH DURING THE AFTERNOON HOURS. LIGHT
AM WINDS FOR KIPL TO GIVE WAY TO SOUTHWESTERLY BREEZES BY THE AFTN
AND ELEVATED SOUTHERLY HEADINGS TO HOLD FOR KBLH. THE ONLY VARIANT
IN WINDS WILL BE FROM STORM AND OUTFLOW WINDS ONCE STORMS BEGIN TO
DEVELOP LATER INTO THE DAY.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY...
LIMITED MOISTURE WILL BE PRESENT ACROSS MOSTLY EASTERN PORTIONS OF
ARIZONA THROUGH THE WEEKEND ALLOWING FOR AFTERNOON/EVENING SLIGHT
CHANCES FOR SHOWERS AND THUNDERSTORMS MAINLY OVER HIGHER TERRAIN
LOCATIONS NORTH AND EAST OF PHOENIX. INCREASING MOISTURE INTO EARLY
NEXT WEEK WILL PUSH CHANCES OF SHOWERS AND THUNDERSTORMS INTO THE
SOUTHERN AND WESTERN ARIZONA DESERTS. MINIMUM RELATIVE HUMIDITIES OF
10 TO 20 PERCENT RANGE WILL BE COMMON ACROSS THE DESERTS THIS
WEEKEND WITH SOME IMPROVEMENT GOING INTO EARLY NEXT WEEK. DRIEST
LOCATION WILL BE SOUTHEAST CALIFORNIA THIS WEEKEND WITH MINIMUM RH
VALUES INTO THE SINGLE DIGITS. HIGH TEMPERATURES WILL BE AROUND OR
SLIGHTLY ABOVE NORMAL THROUGH THE PERIOD. WINDS WILL BE LIGHT
THROUGH MUCH OF THE PERIOD FOLLOWING TYPICAL DIURNAL DIRECTIONS
EXCEPT FOR AFTERNOON UPSLOPE BREEZES GUSTING AT TIMES UP TO 20 MPH.

&&

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

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PHOENIX AZ
1252 PM MST THU AUG 6 2015

AZZ020-021-026-062045-
LOWER COLORADO RIVER VALLEY AZ AZ-WEST CENTRAL DESERTS AZ-
SOUTHWEST DESERTS AZ-
1252 PM MST THU AUG 6 2015

...SIGNIFICANT WEATHER ADVISORY...

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

SIGNIFICANT WEATHER ADVISORY FOR...
  NORTHEASTERN YUMA AND CENTRAL LA PAZ COUNTIES

UNTIL 145 PM MST

AT 1248 PM MST...WEATHER RADAR DETECTED DEVELOPING THUNDERSTORMS
ALONG INTERSTATE 10...25 TO 30 MILES EAST OF QUARTZSITE.
THUNDERSTORMS ARE FORECAST TO DEVELOP AND SPREAD ACROSS YUMA AND LA
PAZ COUNTIES THE REMAINDER OF THE AFTERNOON...WITH THE MAIN WEATHER
HAZARD BEING STRONG WIND GUSTS TO 50 MPH.

LOCATIONS IMPACTED INCLUDE...
QUARTZSITE...BOUSE...VICKSBURG...WENDEN...YUMA PROVING GROUND...
BRENDA...SALOME...VICKSBURG JUNCTION...HARCUVAR...KOFA WILDLIFE
REFUGE AND PALM CANYON.

LAT...LON 3301 11352 3309 11445 3406 11427 3407 11342
TIME...MOT...LOC 1948Z 240DEG 49KT 3387 11359

HV

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PHOENIX AZ
151 PM MST THU AUG 06 2015

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

0142 PM     TSTM WND GST     1 S BOUSE               33.92N 114.00W
08/06/2015  M62 MPH          LA PAZ             AZ   TRAINED SPOTTER

            AND MEASURED 0.5 IN. OF RAIN FALLEN IN 30 MINUTES

&&

EVENT NUMBER PSR1500092

PSR

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PHOENIX AZ
202 PM MST THU AUG 06 2015

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

0141 PM     TSTM WND DMG     1 ESE QUARTZSITE        33.66N 114.20W
08/06/2015                   LA PAZ             AZ   FIRE DEPT/RESCUE

            3 SEMI TRUCKS BLOWN OVER ON I-10 BETWEEN MILPOSTS 20
            AND 23

&&

EVENT NUMBER PSR1500093

PSR