149
FXUS65 KPSR 142352
AFDPSR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
452 PM MST WED MAY 14 2025
UPDATE
UPDATED AVIATION DISCUSSION.
DISCUSSION
KEY MESSAGES:
1) NEAR TO BELOW NORMAL TEMPERATURES THROUGH THE BEGINNING OF NEXT
WEEK
2) GUSTY WINDS OVER THE WEEKEND RESULTING IN A LOCALLY ELEVATED
FIRE DANGER
3) POTENTIAL FOR VERY WARM WEATHER RETURNING TOWARDS THE LATTER
HALF OF NEXT WEEK
WEATHER PATTERN OVERVIEW:
EARLY AFTERNOON WV IMAGERY DEPICTS ONE VORTICITY CENTER LIFTING
THROUGH THE CENTRAL ROCKIES WHILE LINGERING WEAKNESS IN THE MIDLEVEL
HEIGHT FIELDS AND SOME MEASURE OF LONGWAVE TROUGHING HOVERS OVER THE
SW CONUS. H5 HEIGHTS WILL REACH A MINIMUM NEAR 570DM TODAY THOUGH
ONLY MODEST HEIGHT RISES WILL COMMENCE OVER THE NEXT 48 HOURS WITH
READINGS APPROACHING 576DM UNDER A BROADLY CYCLONIC/ZONAL-FLOW TYPE
PATTERN. CORRESPONDING MIDDLE AND LOWER TROPOSPHERIC TEMPERATURES
SHOULD RESPOND ACCORDINGLY RESULTING IN READINGS RETURNING TO A NEAR
NORMAL LEVEL THOUGH THE END OF THE WEEK.
ENSEMBLES STILL EXHIBIT MODEST FORECAST SPREAD WITH RESPECT TO
STRONG PACIFIC JET ENERGY BUCKLING OVER THE WESTERN CONUS AS
NORTHERN STREAM PV FILLS INTO THE VOID LEFT IN THE SOUTHWEST BY THE
SYSTEM CURRENTLY EJECTING EASTWARD. TRENDS AMONG THE ENTIRE ENSEMBLE
SUITE FAVORS A CONCEPTUAL MODEL MENTIONED IN EARLIER DISCUSSIONS
WITH A PREFERENCE TOWARDS A DEEPER AND SLOWER SOLUTION, THOUGH THERE
IS STILL A MINORITY OF EVIDENCE SHOWING A SINGULAR, FAST MOVING
SHORTWAVE SWEEPING THROUGH THE REGION. IN ALL LIKELIHOOD, A SERIES
OF VORTICITY CENTERS WILL PIVOT AND DIG THROUGH THE TROUGH BASE
DURING THE WEEKEND AND EARLY NEXT WEEK WITH H5 HEIGHTS PLUMMETING
CLOSE TO 560DM OVER MUCH OF THE CWA. WHILE THIS WILL CERTAINLY BRING
ANOTHER BRIEF RESPITE OF BELOW NORMAL TEMPERATURE EARLY NEXT WEEK,
THE PATTERN CHARACTERIZED BY THE JUXTAPOSITION OF ROBUST HEIGHT
FALLS AND STRONG BASAL JET CORE SHOULD YIELD A ROUND OF VERY GUSTY
WINDS, LOCALLY REACHING NEAR CRITICAL FIRE WEATHER THRESHOLDS AND
NECESSITATING SOME WIND ADVISORIES.
FOLLOWING THE PASSAGE OF THIS TROUGH TOWARDS THE MIDDLE OF NEXT
WEEK, THE PREPONDERANCE OF ENSEMBLE MEMBERSHIP SUGGESTS RIDGING MORE
AGGRESSIVELY BUILDING INTO THE REGION. THERE IS A NOTABLE SUBSET OF
MODELS SUGGESTING SOME AMOUNT OF LINGERING TROUGHING PRECLUDING
RAPID HEIGHT RISES, HOWEVER THE PATTERN EVOLUTION WOULD TEND TO
FAVOR A QUICKER RETURN TO ANOMALOUSLY HIGH MIDLEVEL HEIGHTS. IN THE
END, IT WOULD NOT BE OUT OF THE QUESTION FOR H5 HEIGHTS TO ECLIPSE
588DM AND TEMPERATURES TO INCREASE CLOSER TO 10F ABOVE THE DAILY
NORMALS DURING THE LATTER HALF OF THE WEEK.
FORECAST CONFIDENCE & DEVIATIONS:
NARROW GUIDANCE SPREAD THE REMAINDER OF THE WEEK HAS YIELDED VERY
GOOD CONFIDENCE WITH RESPECT TO TEMPERATURE FORECASTS. THIS FORECAST
CONFIDENCE DIMINISHES EARLY NEXT WEEK AS THE UNCERTAINTY REGARDING
THE DEPTH AND SPEED OF THE UPPER TROUGH EXPANDS. HAD TO REMOVE THE
TYPICAL BOGUS NBM POP ARTIFACTS THROUGH PARTS OF THE FORECAST IN
ADDITION TO VARIOUS UNREALISTIC QPF GRIDS. STRANGELY, THE PORTION OF
THE FORECAST PERIOD WITH THE GREATEST SHOWER POTENTIAL (MONDAY
AFTERNOON) HAD VERY LITTLE REFLECTION IN THE MANDATED NBM
INITIALIZATION, AND WOULD EXPECT AN EVENTUAL INCREASE IN THESE
AUTOMATED FORECAST VALUES.
AVIATION
UPDATED AT 2352Z.
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, KDVT:
WINDS WILL FOLLOW THEIR TYPICAL DIURNAL TENDENCIES THROUGH THE TAF
PERIOD. CURRENT WESTERLY WINDS WILL HAVE THEIR TYPICAL SHIFT TO
EASTERLY DURING THE LATE EVENING/OVERNIGHT HOURS, WITH A SHIFT
BACK WESTERLY BY TOMORROW AFTERNOON. ELEVATED WIND SPEEDS, WITH
GUSTS TO AROUND 15-20 KTS, WILL GRADUALLY SUBSIDE OVER THE NEXT
COUPLE OF HOURS. SOME AFTERNOON GUSTS INTO THE TEENS ARE EXPECTED
TOMORROW AS WELL. OTHERWISE, WIND SPEEDS WILL GENERALLY BE AOB 8
KT. SKIES WILL BE MOSTLY CLEAR.
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:
WINDS, AT BOTH TAF SITES, WILL SHIFT WESTERLY THIS EVENING, WITH
WIND SPEEDS AT KIPL GENERALLY AOB 10 KT AND AT KBLH, WIND SPEEDS
MOSTLY AOB 8. SKIES WILL BE MOSTLY CLEAR, WITH ONLY A FEW PASSING
HIGH CIRRUS TONIGHT.
FIRE WEATHER
WEAKENING WIND SPEEDS AND COOLING TEMPERATURES WILL REDUCE THE FIRE
DANGER THE NEXT SEVERAL DAYS, HOWEVER ANOTHER WEATHER SYSTEM WILL
CREATE GUSTY WINDS OVER THE WEEKEND. UNDER TYPICAL SPRINGTIME
UPSLOPE GUSTINESS WITH GUSTS 15-25 MPH, MINIMUM HUMIDITY VALUES WILL
FALL INTO THE 10-15% RANGE THE NEXT SEVERAL DAYS FOLLOWING POOR TO
FAIR OVERNIGHT RECOVERY OF 25-50%. GUSTY WINDS WILL MATERIALIZE
AGAIN THIS WEEKEND WITH THE NEXT WEATHER DISTURBANCE, HOWEVER
COOLING TEMPERATURES AND INCREASED HUMIDITY LEVELS MAY PRECLUDE
WIDESPREAD OR PROLONGED CRITICAL CONDITIONS. AT THIS TIME, SATURDAY
AFTERNOON POSES THE GREATEST THREAT OF AN ELEVATED FIRE DANGER IN
EASTERN DISTRICTS.
PSR WATCHES/WARNINGS/ADVISORIES
AZ...NONE.
CA...NONE.
DISCUSSION...18/SMITH
AVIATION...BENEDICT/18
FIRE WEATHER...SMITH/18
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