TORNADO WARNING

TORNADO WARNING
ISSUED:   170043Z
VALID:     170043Z - 170130Z

A TORNADO WARNING (NOT OFFICIAL) IS IN EFFECT FOR SOUTHERN NAVAJO AND NORTHERN GILA COUNTRY UNTIL 6:30PM MST.

AT 5:45PM MST...RADAR INDICATED A SEVERE THUNDERSTORM SHOWING STRONG LOW-LEVEL ROTATION  JUST NORTH OF CIBECUE.

THE STORM IS MOVING WEST SOUTHWEST AT 15 MPH.

COMMUNITIES AFFECTED BY THIS DANGEROUS STORM OVER THE NEXT HOUR WILL BE:

...YOUNG
...CIBECUE

PERSONS IN THESE AREAS SEEK SHELTER IMMEDIATELY IN A BASEMENT OR LOW LYING AREA.

RS...

SEVERE WEATHER OUTLOOK

SEVERE WEATHER OUTLOOK
VALID:  170030Z - 171200Z

DEFINITIONS...
NOTICE LEVEL...THIS REPRESENTS A GREATER THAN 5 % CHANCE OF SEVERE WEATHER OCCURING WITHIN THE GREEN REGION ON THE MAP.
CAUTION LEVEL...THIS REPRESENTS A GREATER THAN 10% CHANCE OF SEVERE WEATHER OCCURING WITHIN THE YELLOW REGION ON THE MAP.

ALERT LEVEL...THIS REPRESENTS A GREATER THAN 30% CHANCE OF SEVERE WEATHER OCCURING WITHIN THE RED REGION ON THE MAP.

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THERE IS A SEVERE WEATHER NOTICE IN EFFECT FOR THE GREATER PHOENIX AREA FOR TONIGHT UNTIL 5AM MST.

A SEVERE WEATHER NOTICE MEANS THAT THERE IS A GREATER THAN 5% CHANCE THAT THERE MAY BE SEVERE WEATHER IN THE AREA FROM NOW UNTIL 5AM MST.

CONDITIONS INDICATE THERE IS A POTENTIAL FOR SEVERE WEATHER TO DEVELOP LATER ON THIS AFTERNOON AND EVENING WITHIN THE PHOENIX AREA.  A SEVERE WEATHER WATCH OR WARNING MAY BE EXPECTED LATER, AND PERSONS IN THE NOTICE AREA SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER CONDITIONS.

RISKS IN NOTICE AREA
...TORNADOES...<1 %
...DAMAGING WINDS...< 8 %
...DAMAGING HAIL...< 2 %


RS...

SPECIAL WEATHER STATEMENT

SPECIAL WEATHER STATEMENT
ISSUED:  170014Z

LARGE BROKEN AREA OF STRONG THUNDERSTORMS OVER NORTHERN ARIZONA CONTINUES TO MOVE MAINLY WESTWARD, BUT WITH SOME EXPANSION SOUTHWEST.

AT 5PM...RADAR INDICATE A CLUSTERS OF STRONG THUNDERSTOMRS THAT STRETCHED FROM NEAR WICKENBURG, TO NEW RIVER NORTH TO WILLIAMS. RADAR ESTIMATED RAINFALL RATES OF 1.00 INCH TO 2.00 PER HOUR WERE POSSIBLE WITH THESE STORMS.

ANOTHER CLUSTER OF STRONG STORMS EXTENDED FROM NEAR HEBER TO SHOWLOW TO PINETOP-LAKESIDE.   RADAR ALSO INDICATED THAT SMALL HAIL WAS POSSIBLE WITH THESE STORMS.  RAINFALL RATES OF 1.5 TO 2.0 PER HOUR WERE POSSIBLE WITH THESE STORMS.

ALL STORMS ARE MAINLY MOVING WEST SOUTHWEST AT 15 TO 20 MPH.

AREAS TO BE AFFECTED BY THESE STORM OVER THE NEXT HOUR WILL BE...
..WICKENBURG
..NEW RIVER
..BLACK CANYON CITY
..WILLIAMSON
..PRESCOTT
..CAMP VERDE
..PINE
..CAREFREE
..TONTO BASIN
..YOUNG
..PAYSON
..CIBECUE
..HEBER

PERSONS IN THE PATH OF THESE STORMS SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER CONDITIONS AND GO TO A PLACE OF SAFETY IF STORMS APPROACH YOUR AREA.

RS...

PHOENIX FORECAST

PHOENIX FORECAST
VALID:  170000Z - 171200Z


TONIGHT...
MOSTLY CLOUDY, CONTINUED VERY WARM AND HUMID.  A SLIGHT CHANCE FOR A EVENING THUNDERSTORM OR DUST STORM MAINLY NORTH OF THE VALLEY.  BREEZY IN THE EVENING.  LOWS IN THE LOW TO MID 90S.

SATURDAY...
MOSTLY CLOUDY IN THE MORNING, THEN TURNING PARTLY CLOUDY IN THE AFTERNOON.  CONTINUED VERY HOT AND HUMID.  A SLIGHT CHANCE FOR A DUST STORM OR THUNDERSTORM TOWARDS THE EVENING.  HIGHS FROM 108 TO 110.

SATURDAY NIGHT...
PARTLY CLOUDY AND CONTINUED WARM AND HUMID.  A SLIGHT CHANCE FOR A DUST STORM AND THUNDERSTORM IN THE EVENING.  LOWS IN THE LOW TO MID 90S.

EXTENDED FORECAST....SUNDAY, MONDAY, TUESDAY
PARTLY TO MOSTLY SUNNY, CONTINUED HOT AND HUMID.  HIGHS FROM 108 TO 110.  LOWS IN THE UPPER 80S TO LOW 90S.

FORECAST DISCUSSION

FORECAST DISCUSSION
VALID:  162048Z
ISSUED: 162000Z - 170000Z

SYNOPSIS...
VW SAT SHOWED SEVERAL WK VORT LOBS MOVING AROUND HIGH PRESS CENTER IN THE UPPER LVLS OVER NM.  TWO WK LOBS ARE NOT BEING FORCED NNE OVR CA WHICH MAY HAVE A EFFECT ON STORMS TODAY.  ANOTHER IS BEING SHEARED APART OVER WESTERN TX.

BECAUSE OF THE POTENTIAL BEING EXPRESSED BY NWS OF THE TSTORM OUTBREAK ACROSS AZ, I WILL FOCUS THIS DISCUSSION ON THAT POSSIBILITY.

INHIBITING FACTORS TO OUTBREAK...
UPR LEVEL SUPPORT IS THERE IN THE 300 / 250 MB WE HAVE A MOD SE FLOW OF 20 TO 25KTS WINDS AROUND HIGH PRESS LOCATED OVER NM.  THIS WILL HELP WITH VENTING STORMS, BUT MAY CAUSE LARGE ANVIL SHIELDS WHICH MAY REDUCE THE AMOUNT OF STORM DEVELOPMENT ESPECIALLY DOWN WIND IN THE DESERT LOCATIONS.

FLOW IN MID LEVELS IS STILL VERY WEAK AND THUS I BELIEVE STORMS WILL NOT MOVE MUCH.  THUS, THEY WILL BECOME MORE PULSE LIKE IN NATURE, BUT AS THEY ATTEMPT TO APPROACH THE DESERT THEY WILL QUICKLY DIE OUT.

ANOTHER FACTOR IS THE INVERTED TROUGH NOW MOVING NNE INTO CA.  THESE TEND TO BRING UP DRIER AIR FROM THE PACIFIC.  SO THIS MAY ALSO CAUSE A REDUCTION IN OUR LOW LEVEL MOISTURE.

FORECAST TODAY...
I BELIEVE STORMS THAT DO DEVELOP WILL HAVE THE POTENTIAL TO GET STRONG AND POSSIBLY SEVERE IN NATURE - MAINLY DAMAGING WINDS.  BUT I BELIEVE MOST OF THE STORMS WILL REMAIN IN THE MOUNTAIN REGIONS.  OUTFLOWS MAY SPARK A FEW SHORT LIVED STORMS ON THE EASTERN HIGH DESERTS, BUT AGAIN I BELIEVE THEY WILL BE SHORT LIVED.

I DO BELIEVE WE HAVE THE POTENTIAL FOR DUST STORMS ON THE DESERTS WITH STRONG POSSIBLY DAMAGING WINDS.

EXTENDED FORECAST...
LOOKS LIKE WE WILL KEEP THE ABOVE NORMAL TEMPS AND MOISTURE FOR NOW.  THERE MAY BE SOME ATTEMPT IN THE LONG RANGE TO DRY THINGS OUT, BUT THE MODELS ARE FLIP FLOPPING ON THAT POTENTIAL.

RS...