000
FXUS65 KPSR 200428
AFDPSR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
925 PM MST FRI MAR 19 2010
.SYNOPSIS...
HIGH PRESSURE WILL BUILD OVER THE REGION AND BRING WARM TEMPERATURES
AND DRY CONDITIONS THROUGH THE WEEKEND INTO EARLY NEXT WEEK.
TEMPERATURES WILL WARM ONCE AGAIN TO ABOVE NORMAL STARTING SUNDAY
AND MONDAY BEFORE COOLING AS ANOTHER LOW PRESSURE SYSTEM SKIRTS
EASTERN ARIZONA ON WEDNESDAY.
&&
.DISCUSSION...
GENERALLY CLEAR SKIES THIS EVENING OVER MOST OF ARIZONA...JUST A
SMALL AREA OF THUNDERSTORM ACTIVITY LINGERING OVER EAST-CENTRAL
PORTIONS OF THE STATE AT THIS HOUR. THE UPPER LEVEL LOW THAT SWEPT
ACROSS SOUTHEAST CALIFORNIA AND ARIZONA TODAY CAN BE SEEN IN WV/IR
SAT IMAGERY SWINGING EAST THROUGH NEW MEXICO...AND THE TROF WILL
CONTINUE AN EASTWARD PROGRESSION INTO THE SOUTHERN GREAT PLAINS AND
TEXAS SATURDAY. A DRIER AIRMASS IS OVERSPREADING OUR CWA BEHIND THE
DEPARTING TROF...WITH DEW POINTS FALLING INTO THE TEENS AND LOW 20S
AT MANY LOCATIONS. THE DRIER CONDITIONS WILL ALLOW NIGHTTIME LOWS TO
COOL OFF NICELY...MAYBE 4-6 DEGREES COOLER IN SOME OUTLYING DESERT
LOCATIONS.
THE GFS AND ECMWF IN GOOD AGREEMENT AS TO THE ESTABLISHMENT OF THE
RIDGE OVER THE DESERT SOUTHWEST FOR THE NEXT 24-36 HOURS. UNDER
MOSTLY SUNNY SKIES...DAYTIME HIGHS EXPECTED TO WARM NICELY BACK INTO
THE LOW TO MID 80S BY MONDAY...AND MINIMUM RH LEVELS WILL REMAIN LOW
THROUGH THE PERIOD. AS THE HIGH RE-ESTABLISHES...SFC/LOW LEVEL WINDS
WILL FAVOR NORTH AND EAST DIRECTIONS...BECOMING LOCALLY GUSTY AT
TIMES...ESPECIALLY LATE SATURDAY MORNING...AND TO A LESSER EXTEND
SUNDAY.
OTHER THAN SOME MINOR ADJUSTMENTS TO THE INHERITED SHORT TERM
DIGITAL GRIDS...THE FORECAST IS IN GOOD SHAPE AND NO CHANGES MADE AT
THIS TIME.
PREVIOUS DISCUSSION...
THE NEXT STORM SYSTEM...THIS ONE COMING OFF THE PACIFIC ACROSS
SOUTHERN CALIFORNIA...WILL BEGIN TO MOVE INTO OUR CWA. NOT MUCH
PRECIP IS INDICATED WITH THIS SYSTEM AND IS FORECAST TO MERGE IN
WITH A ROCKY MOUNTAIN LOW PRESSURE SYSTEM DROPPING DOWN ACROSS THE
GREAT BASIN ON TUESDAY. THIS SECOND SYSTEM WILL SKIRT THE
NORTHEASTERN QUADRANT OF ARIZONA. ATTM NOT MUCH WEATHER IS EXPECTED
FROM EITHER OF THESE TWO LOWS. MAIN IMPACT MAY BE SOME ENHANCED
GRADIENT WIND TUESDAY AND ESPECIALLY WEDNESDAY. GIVEN THAT...HAVE
CUT BACK THE POPS FOR THAT SYSTEM. NOT ANTICIPATING ANY HAZARDOUS
WEATHER ANYMORE FOR THE NEXT SEVEN DAYS...AND SO DECIDED TO
TERMINATE THE HWO AT THE SAME TIME AS THE WIND ADVY WAS CANCELLED.
TEMPERATURES SHOULD REMAIN A LITTLE ABOVE NORMAL FOR THE NEXT FEW
DAYS BEFORE FALLING BACK TO THE 70S WHEN THE WEDNESDAY SYSTEM PASSES
BY. LITTLE OR NO RAIN IS EXPECTED FOR MOST OF THE REGION FOR THE
SEVEN DAYS WITH ONLY A SLIGHT CHANCE FOR WEDNESDAY ACROSS HIGHER
TERRAIN NORTH AND EAST OF PHOENIX.
&&
.AVIATION...
KIPL...KBLH...AND SURROUNDING AIRFIELDS...
NORTHERLY WINDS AROUND 10-15 KTS WILL CONTINUE OVERNIGHT ALONG THE
LENGTH OF THE LOWER COLORADO RIVER VALLEY FORM PARKER SOUTH TO YUMA.
OTHERWISE...MOSTLY CLEAR SKIES AND LIGHT WINDS AT OTHER LOCATIONS IN
THE SE CA DESERTS SUCH AS KIPL/KNJK.
KPHX...KIWA...AND SURROUNDING AIRFIELDS...
MOSTLY CLEAR SKIES OVERNIGHT. WINDS WILL BE GENERALLY LESS THAN
10KTS AT KIWA/KPHX...FAVORING NORTHWEST TO NORTHEAST DIRECTIONS
AFTER 08Z. SFC GRADIENT REMAINS ENHANCED...AND LOW LEVEL WINDS
EXPECTED TO INCREASE AFTER 15Z SATURDAY...MAINLY OVER SOUTH-CENTRAL
ARIZONA...GENERATING GUSTY NORTHEASTERLY WINDS UP TO 25 KTS. WINDS
EXPECTED TO WEAKEN AFTER 20Z...BECOMING LIGHT BY SUNSET.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...
LIGHTER WINDS AND A WARMING TREND ARE ANTICIPATED SUNDAY INTO
MONDAY...BEFORE ANOTHER LOW PRESSURE SYSTEM TRACKS ACROSS THE REGION
TUESDAY INTO WEDNESDAY PROVIDING THE AREA WITH COOLER MAXIMUM
TEMPERATURES AND A SLIGHT CHANCE OF PRECIPITATION. HIGH PRESSURE
RETURNS THURSDAY...ALONG WITH WARMER AND DRIER CONDITIONS.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT
WEATHER.GOV/PHOENIX
DISCUSSION...MEYERS/WATERS
AVIATION...MEYERS
FIRE WEATHER...LEINS
