933
FXUS65 KPSR 070929
AFDPSR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
229 AM MST SAT MAR 7 2026
KEY MESSAGES
- LINGERING LOW PRESSURE WILL HELP KEEP BREEZY TO LOCALLY WINDY
CONDITIONS IN THE FORECAST FOR TODAY.
- A WEATHER SYSTEM CONTINUES TO MEANDER NEAR THE REGION THROUGH
THE START OF NEXT WEEK, ALLOWING FOR AN INCREASE IN RAIN
POTENTIAL FOR MONDAY.
- HIGH PRESSURE, ALONG WITH CONSISTENT ABOVE-NORMAL TEMPERATURES,
MAKE THEIR RETURN BY THE MIDDLE PORTION OF NEXT WEEK.
SHORT TERM /TODAY THROUGH SUNDAY/
CURRENT RAP40 ANALYSIS OF H5 HEIGHTS SHOWS THE CORE OF THE TROUGH
BEGINNING TO SPLIT, AND STARTING TO DEVELOP INTO THE CUT-OFF LOW
MODELS HAVE BEEN HINTING AT THE PAST FEW DAYS. THIS LOW WILL CONTINUE
TO BREAK OFF, TIGHTENING INTO A WELL DEVELOPED CUT-OFF LOW THROUGHOUT
TODAY. BY THIS AFTERNOON THE CENTER OF THE LOW WILL BE OVER THE
NORTHERN BAJA PENINSULA. THE NEGATIVE HEIGHT ANOMALIES ASSOCIATED
WITH THE CUT-OFF WILL MILDLY EFFECT TODAYS AFTERNOON HIGHS WITH
TEMPERATURES EXPECTED IN THE MID TO HIGH 70S ACROSS THE LOWER
DESERTS. BY TOMORROW THE CUT OFF LOW WILL BE JUST OFF THE NW COAST
THE BAJA PENINSULA, ALLOWING FOR H5 HEIGHTS OVER THE DESERT SW TO
CLIMB NEAR 570-573 DAM. HIGH TEMPERATURES FOR SUNDAY IN RESPONSE
WILL BE IN THE UPPER 80S, WITH SOME AREAS ACROSS THE LOWER DESERTS
HAVING 15-25% CHANCE OF REACHING 90 DEGREES.
A RELATIVELY ENHANCED PRESSURE GRADIENT WILL ALSO BE PRESENT THIS
AFTERNOON, BRINGING BREEZY TO LOCALLY WINDY CONDITIONS ESPECIALLY
AROUND THE LOWER COLORADO RIVER VALLEY AND WESTWARD. GUSTS 25- 35
MPH WILL BE COMMON ACROSS THESE AREAS, WITH LOCALLY HIGHER GUSTS
FOCUSED OVER ENHANCED TERRAIN FEATURES. GIVEN THE HIGH LIKELIHOOD OF
ACHIEVING GUSTS GREATER THAN 40 MPH, A WIND ADVISORY HAS BEEN POSTED
FOR PORTIONS OF SE CALIFORNIA FOR SATURDAY MORNING HOURS.
LONG TERM /MONDAY THROUGH FRIDAY/
THE CUT-OFF LOW WILL BE FAIRLY STATIONARY OVER THE WEEKEND BUT COME
MONDAY AFTERNOON WILL BEGIN ITS JOURNEY EASTWARDS OVER NORTHERN
MEXICO/SOUTHERN ARIZONA. MOISTURE ADVECTION INTO THE REGION ASSOCIATED
WITH THIS SYSTEM WILL BEGIN EARLY MONDAY MORNING AND WILL PEAK MONDAY
EVENING INTO TUESDAY MORNING, WITH PWAT ANOMALIES AROUND 180-200%
OF NORMAL. MONDAY EVENING INTO EARLY TUESDAY MORNING WILL ALSO BE
THE BEST CHANCES FOR PRECIPITATION ACROSS MAINLY SOUTH CENTRAL ARIZONA
(25-35%), AND EASTERN ARIZONA INTO THE HIGHER TERRAIN AREAS (45-55%).
QPF TOTALS OVER THE PAST 24 HOURS HAVE TRENDED UPWARDS WITH SC AZ
NOW BETWEEN 0.05-0.15" AND THE HIGHER TERRAIN AREAS BETWEEN 0.15-0.25".
AS THE CORE OF THE CUT-OFF LOW PROGRESSES EASTWARDS OVER NORTHERN
MEXICO/ SOUTHERN ARIZONA, TEMPERATURES WILL COOL INTO THE UPPER 70S
FOR MONDAY AFTERNOON. AFTERWARDS, BY TUESDAY EVENING THE CUT-OFF LOW
WILL BE EJECTING INTO WESTERN TEXAS AND INTO THE PLAINS. ONCE THE
LOW IS TO THE REGION'S EAST, UPPER LEVEL RIDGING WILL TAKE PLACE
OVER THE DESERT SW. WITH STRONG RIDGING MOVING IN, TEMPERATURES BY
MID TO LATE NEXT WEEK WILL CLIMB TO 10-15 DEGREES ABOVE NORMAL, WITH
H5 HEIGHTS ABOVE THE 90TH PERCENTILE OF CLIMATOLOGICAL NORMAL.
AVIATION
UPDATED AT 0540Z.
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:
ASIDE FROM A BRIEF PERIOD OF GUSTY WINDS DEVELOPING MID-MORNING
SATURDAY, AVIATION WEATHER CONCERNS WILL REMAIN MINIMAL THROUGH
THE TAF PERIOD. WINDS WILL SHIFT OUT OF THE EAST OVERNIGHT AND
BECOME MORE ELEVATED AFTER SUNRISE SATURDAY MORNING. GUSTS IN THE
TEENS TO AROUND 20 KTS WILL BECOME COMMON BY MID-MORNING, BUT ARE
EXPECTED TO SLACKEN BY THE LATE AFTERNOON. GUIDANCE DOES INDICATE
WINDS WILL ATTEMPT TO SWITCH OUT OF THE WEST SATURDAY EVENING.
FEW-SCT HIGH CLOUDS WILL PROGRESS THROUGH THE REGION OVERNIGHT.
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:
GUSTY N-NNE WINDS WILL BE THE PRIMARY AVIATION WEATHER CONCERN AT
BOTH TERMINALS SATURDAY MORNING THROUGH SATURDAY AFTERNOON. LIGHT
W-NW FLOW WILL CONTINUE OVERNIGHT WITH SPEEDS REMAINING AOB 8 KTS.
CONFIDENCE IS HIGH THAT GUSTS UP TO 20-25 KTS WILL MATERIALIZE AT
BOTH SITES SATURDAY MORNING AND PERSIST THROUGH MID AFTERNOON.
PERIODS OF FEW-SCT MID TO HIGH CLOUD DECKS WILL PASS OVER THE
REGION, BUT SKIES WILL BECOME MOSTLY CLEAR EARLY SATURDAY.
FIRE WEATHER
THE CURRENT PASSING SYSTEM CONTINUES TO BRING MOSTLY DIURNAL
WINDS ACROSS THE REGION, AND WILL BEGIN TO STRENGTHEN BRINGING
BREEZY TO WINDY CONDITIONS THIS AFTERNOON, MAINLY IN THE WESTERN
DISTRICTS. DRY CONDITIONS WILL PERSIST ACROSS THE REGION WITH
MINIMUM RELATIVE HUMIDITY VALUES STAYING ENTRENCHED BETWEEN 10-15%
THROUGH SUNDAY, WHILE OVERNIGHT RECOVERIES WILL ONLY REACH THE
30-45% RANGE. PEAK WIND GUSTS OF 25-35 MPH ACROSS SOUTHEAST
CALIFORNIA AND INTO THE HIGH ELEVATIONS WILL CONTINUE, LEADING TO
ELEVATED FIRE WEATHER CONCERNS BEFORE A POTENTIAL SLIGHT INCREASE
IN MOISTURE ARRIVES MONDAY. MONDAY'S WEATHER SYSTEM WILL HELP
SHORTLY INCREASE MINRHS TO BETWEEN 30-40% WITH GOOD OVERNIGHT
RECOVERIES BEFORE RETURNING TO DRIER CONDITIONS BY MID NEXT WEEK.
PSR WATCHES/WARNINGS/ADVISORIES
AZ...NONE.
CA...WIND ADVISORY UNTIL NOON PST SATURDAY FOR CAZ560-561-564-568>570.
SHORT TERM...RYAN/RW
LONG TERM...RYAN
AVIATION...SALERNO
FIRE WEATHER...RYAN
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