193
FXUS65 KPSR 101009
AFDPSR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
309 AM MST SAT MAY 10 2025
SYNOPSIS
THE TEMPERATURES THIS WEEKEND ARE FORECASTED TO BE THE HOTTEST
TEMPERATURES OF THE YEAR, SO FAR. WITH HIGH PRESSURE FIRMLY OVERHEAD
IT WILL ALLOW TEMPERATURES TO WARM INTO THE 100-108 DEGREE RANGE
ACROSS THE LOWER DESERTS. THESE SEASONABLY HOT TEMPERATURES WILL
RESULT IN WIDESPREAD MODERATE TO LOCALIZED MAJOR HEATRISK ACROSS THE
LOWER DESERTS. DAILY BREEZY CONDITIONS WILL DEVELOP LATER THIS
MORNING AND CONTINUE INTO NEXT WEEK AS THE NEXT WEATHER SYSTEM MOVES
INTO THE REGION BY THE BEGINNING OF NEXT WEEK. THIS WEATHER SYSTEM
WILL BE DRY, BUT IT WILL BRING COOLER TEMPERATURE BACK TO THE
REGION.
DISCUSSION
EARLY THIS MORNING UPPER-LEVEL WATER VAPOR IMAGERY DEPICTS HIGH
PRESSURE OVER SOUTHWESTERN CONUS, A LOW OVER LOUISIANA, A LOW OVER
NEW ENGLAND, AND A LOW IN THE GULF OF ALASKA. H5 HEIGHTS OVERHEAD
ARE CURRENTLY AROUND 582DM AND ARE EXPECTED TO STRENGTHEN TO 583-
585DM THIS AFTERNOON AS THE CENTER OF THE HIGH PRESSURE SYSTEM MOVES
OVERHEAD. THE HIGH PRESSURE SYSTEM WON'T MOVE MUCH TOMORROW AS H5
HEIGHTS ARE EXPECTED TO BE SIMILAR TO TODAY. AS A RESULT FORECASTED
HIGH TEMPERATURES FOR THIS AFTERNOON AND TOMORROW AFTERNOON ARE VERY
SIMILAR. LOWER DESERT COMMUNITIES ARE FORECASTED TO SEE HIGHS IN
THE 100-108 DEGREE RANGE WITH HIGHER ELEVATION AREAS FORECASTED TO
SEE HIGHS RANGING FROM THE UPPER 80S TO THE UPPER 90S. THESE HOT
TEMPERATURES WILL RESULT IN LOCALIZED AREAS OF MAJOR HEATRISK,
WITH WIDESPREAD MODERATE HEATRISK ACROSS THE LOWER DESERTS FOR
TODAY AND TOMORROW. THE HIGH TEMPERATURES THIS WEEKEND ARE
FORECASTED TO BE THE HOTTEST OF THE YEAR, SO FAR. SO MAKE SURE TO
PRACTICE SMART HEAT SAFETY BY LIMITING YOUR TIME OUTDOORS, WEARING
SUNSCREEN, WEARING LIGHT LOOSE FITTING CLOTHES, AND STAYING
HYDRATED. ONE CAVEAT TO THE CURRENT FORECAST IS THAT TOMORROW
AFTERNOON WE WILL SEE INCREASING HIGHER LEVEL CLOUDS MOVE INTO THE
REGION WHICH COULD KEEP SOME LOCATIONS FROM REACHING THE CURRENT
NBM FORECAST HIGHS.
AS THE PRESSURE GRADIENT TIGHTENS BETWEEN THE LOW PRESSURE OVER
LOUISIANA AND THE HIGH PRESSURE AS THE CENTER MOVES OVERHEAD TODAY
BREEZY CONDITIONS WILL DEVELOP OUT OF THE EAST/SOUTHEAST. THESE
BREEZY CONDITIONS ARE EXPECTED TO DEVELOP ACROSS MUCH OF SOUTHERN
AND CENTRAL ARIZONA BEGINNING AROUND SUNRISE THIS MORNING. WIND
GUSTS OF 25-35 MPH ARE EXPECTED THIS MORNING WITH A SLIGHT DECREASE
HEADING INTO THE AFTERNOON HOURS. WINDS WILL SET UP VERY SIMILAR
TOMORROW, BUT SPEEDS WILL BE AROUND 5 MPH LOWER.
GLOBAL ENSEMBLES SHOW THE AFOREMENTIONED LOW PRESSURE, CURRENTLY IN
THE GULF OF ALASKA, MOVING ONSHORE IN THE PACIFIC NORTHWEST BY LATE
THIS WEEKEND/VERY EARLY NEXT WEEK. ENSEMBLES SHOW THE LOW
APPROACHING OUR AREA AROUND TUESDAY. AS THIS LOW PRESSURE MOVES
ONSHORE AND PUSHES INTO OUR REGION TEMPERATURES WILL START TO
DECREASE. AFTERNOON HIGH TEMPERATURES ON MONDAY ARE FORECASTED TO
BE IN THE UPPER 90S TO LOW 100S ACROSS THE LOWER DESERTS. FURTHER
COOLING WILL TAKE PLACE AS THE LOW PUSHES INTO OUR REGION ON
TUESDAY AND ON WEDNESDAY AS THE BASE OF THE TROUGH MOVES THROUGH
OUR AREA. ENSEMBLES AGREE THAT THE CENTER OF THE LOW WILL STAY
WELL TO OUR NORTH, SO WE WON'T SEE AS DRAMATIC OF A COOL DOWN AS
WE DID AT THE BEGINNING OF THIS WEEK. BUT, TEMPERATURES ARE
CURRENTLY FORECASTED TO FALL BELOW NORMAL ON WEDNESDAY, WITH
AFTERNOON HIGH TEMPERATURES CURRENTLY FORECASTED TO BE IN THE 80S
ACROSS THE LOWER DESERTS. GLOBAL ENSEMBLE MODELS START TO DIFFER
A LITTLE ON THE HOW LONG THE LOW WILL LINGER OVER WESTERN CONUS.
HOWEVER, MOST MEMBERS SHOW THE LOW WEAKENING, BUT LINGERING ACROSS
OUR REGION FOR THE LATTER HALF OF NEXT WEEK. THIS WOULD ALLOW
TEMPERATURES TO WARM TO NEAR NORMAL FOR THE END OF NEXT WEEK.
AVIATION
UPDATED AT 0020Z.
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, KDVT:
EASTERLY WINDS WILL PREVAIL THROUGH THE TAF PERIOD. AN ENHANCED
EASTERLY GRADIENT WIND WILL DEVELOP TONIGHT, SHORTLY AFTER
MIDNIGHT. WINDS ABOVE THE SURFACE AS HIGH AS 30-35 KTS MAY LEAD
LLWS MAGNITUDES UP TO 25-30 KTS BETWEEN 7-14Z, BUT MENTION WILL BE
LEFT OUT OF THE TAF. THE ELEVATED WINDS WILL LEAD TO SURFACE WIND
GUSTS TO AROUND 25-30 KTS SATURDAY, MAINLY BETWEEN 15-20Z. GUST
MAGNITUDES WILL SUBSIDE GRADUALLY THROUGH SATURDAY AFTERNOON.
SKIES WILL REMAIN MOSTLY CLEAR.
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:
LIGHT DIURNAL WINDS WILL PREVAIL AT BOTH TERMINALS THROUGH
TONIGHT, WITH PERIODS OF LIGHT VARIABILITY AS WELL. AN INCREASED
EASTERLY WIND GRADIENT WILL THEN TAKE HOLD BY LATE MORNING AT BOTH
TERMINALS, WITH SURFACE SPEEDS INCREASING TO AROUND 8-13 KTS WITH
GUSTS UP TO 15-25 KTS THAT WILL CONTINUE THROUGH EARLY AFTERNOON
SATURDAY. MOSTLY CLEAR SKIES WILL PREVAIL, WITH FEW TO SCT HIGH
CLOUDS MOVING IN LATE IN THE AFTERNOON AND EVENING SATURDAY.
FIRE WEATHER
WITH HIGH PRESSURE FIRMLY OVERHEAD THIS WEEKEND, TEMPERATURES WILL
CLIMB INTO THE 100-108 DEGREE RANGE ACROSS THE LOWER DESERTS AND
MOST HIGHER ELEVATIONS WILL SEE HIGH TEMPERATURES RANGING FROM
THE UPPER 80S TO UPPER 90S. MINRHS WILL BE IN THE 7-15% RANGE
THROUGH MONDAY. BREEZY CONDITIONS WILL DEVELOP AROUND SUNRISE
ACROSS SOUTHERN AND CENTRAL ARIZONA WITH GUSTS OF 25-35 MPH
EXPECTED OUT OF THE EAST/SOUTHEAST. SPEEDS WILL DECREASE A LITTLE
HEADING INTO THE AFTERNOON TODAY. A SIMILAR WIND PATTERN IS
EXPECTED TOMORROW WITH SPEEDS AROUND 5 MPH LOWER THAN TODAY. THE
BREEZY CONDITIONS WILL ALSO EXPAND INTO THE WESTERN DISTRICTS
TOMORROW. THESE BREEZY CONDITIONS AND LOW RHS COULD RESULT IN
SOME ELEVATED FIRE DANGER IN SOME AREAS THIS WEEKEND. A LOW
PRESSURE SYSTEM WILL MOVE INTO THE REGION EARLY NEXT WEEK. WHILE
THIS SYSTEM WILL BRING COOLER CONDITIONS IT WILL ALSO BRING MORE
BREEZY TO WINDY CONDITIONS LIKELY LEADING TO A CONTINUATION OF
ELEVATED FIRE DANGER.
PSR WATCHES/WARNINGS/ADVISORIES
AZ...NONE.
CA...NONE.
DISCUSSION...BERISLAVICH
AVIATION...BENEDICT
FIRE WEATHER...BERISLAVICH
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page