870
FXUS65 KTWC 041802
AFDTWC
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
1102 AM MST SAT APR 4 2026
SYNOPSIS
SOUTHEAST ARIZONA WILL BE WARM WITH PASSING HIGH
CLOUDS TODAY. A BACKDOOR SURFACE FRONT WILL BEGIN TO NUDGE INTO
THE REGION FROM THE EAST TONIGHT, RESULTING IN BREEZY EAST TO
SOUTHEAST WINDS BOTH SUNDAY AND MONDAY. THESE WINDS WILL BE
CAPABLE OF KICKING UP SOME LOCALIZED BLOWING DUST, ESPECIALLY
ACROSS THE UPPER GILA RIVER AND SAN SIMON VALLEYS NEAR THE
ARIZONA AND NEW MEXICO STATE LINE. A MINOR MOISTURE INCREASE
ALONG THIS FRONT AND A PASSING WEATHER DISTURBANCE ALOFT WILL
RESULT IN A SLIGHT CHANCE OF MAINLY MOUNTAIN SHOWERS MONDAY.
DISCUSSION
THE UPPER PATTERN TODAY IS DEFINED BY AN
AMPLIFIED RIDGE OF HIGH PRESSURE ACROSS CALIFORNIA, A TROUGH
WEST OF THIS FEATURE WITH AN UPPER-LOW CENTERED NEAR 34N/135W,
AND A LARGE SCALE TROUGH TO OUR EAST WITH AN UPPER LOW CENTERED
OVER THE UPPER MIDWEST. GENERALLY ZONAL UPPER FLOW IMPACTING
SOUTHEAST ARIZONA TODAY WITH A DIRTY FLOW OF MAINLY HIGH CLOUDS
PASSING THROUGH THE REGION FROM WEST TO EAST. THE WESTERN
PERIPHERY OF A SURFACE HIGH PRESSURE SYSTEM MOVING SE OUT OF THE
ROCKIES TODAY WILL RESULT IN A BACKDOOR FRONT NUDGING INTO
SOUTHEAST ARIZONA FROM THE EAST BEGINNING LATE THIS AFTERNOON
AND PERSISTING INTO MONDAY. THIS FRONT ISN'T AS STRONG AS THE
ONE THAT IMPACTED OUR NECK OF THE WOODS LAST WEEK, BUT IT WILL
BE STRONG ENOUGH TO BRING BREEZY TO WINDY EAST TO SOUTHEAST
WINDS 15 TO 25 MPH WITH GUSTS TO 35-40 MPH BOTH SUNDAY AND
MONDAY. THESE WINDS WILL BE CAPABLE OF KICKING UP SOME LOCALIZED
BLOWING DUST, REDUCING VISIBILITIES...ESPECIALLY ACROSS THE
UPPER GILA RIVER AND SAN SIMON VALLEYS NEAR THE ARIZONA/NEW
MEXICO STATE LINE. AN AIR QUALITY ALERT REMAINS IN EFFECT FOR
COCHISE COUNTY SUNDAY BY THE ARIZONA DEPARTMENT OF ENVIRONMENT
QUALITY (ADEQ) DUE TO THE POTENTIAL FOR DUST.
ENSEMBLE MEMBERS OF THE NBM CONTINUE TO TRY TO ADVECT MOISTURE
INTO THE AREA FROM THE EAST/SOUTHEAST ALONG THE SURFACE FRONTAL
BOUNDARY, BUT I AM SKEPTICAL ON THE MAGNITUDE GIVEN THE CURRENT
GOES-18 PRECIPITABLE WATER IMAGERY INDICATING THE DEEPER
MOISTURE SOURCE RESIDING WAY OUT ACROSS EASTERN CHIHUAHUA
MEXICO THIS MORNING. AN IMPULSE TO THE SOUTH OF THE UPPER-LOW
CENTERED IN THE EASTERN PACIFIC THIS MORNING WILL TRACK EAST AND
UNDER-CUT THE UPPER RIDGE IN CALIFORNIA OVER THE NEXT 36 TO 48
HOURS. ALTHOUGH THERE IS SOME MID-LEVEL MOISTURE/WEAK DYNAMICS
ASSOCIATED WITH THIS OPEN FEATURE, I THINK THE PAUCITY OF LOWER
LEVEL MOISTURE MOVING IN FROM THE EAST/SOUTHEAST ALONG THE
FRONTAL BOUNDARY WILL LIMIT THE COVERAGE OF SHOWERS TO MAINLY
THE MOUNTAINS EAST OF TUCSON MONDAY AS IT TRACKS THROUGH. THERE
MAY BE JUST ENOUGH INSTABILITY TO RESULT IN AN EMBEDDED
THUNDERSTORM.
OTHERWISE, THIS DISTURBANCE WILL BE FOLLOWED BY A SHORTWAVE
RIDGE TUESDAY AND WEDNESDAY BEFORE A STRONGER MORE AMPLIFIED
TROUGH BEGINS TO ESTABLISH ITSELF ALONG THE WEST COAST THE
SECOND HALF OF THE WORK WEEK. GIVEN THE ORIENTATION OF THE
DEVELOPING UPPER PATTERN, IT HAS A LOOK OF A WEATHER SYSTEM THAT
WILL EJECT NE THROUGH THE GREAT BASIN...RESULTING IN BREEZY
CONDITIONS FOR SOUTHEAST ARIZONA LATE NEXT WEEK GOING INTO TO
NEXT WEEKEND.
AVIATION
VALID THROUGH 06/00Z. SCT TO BKN CLOUDS AOA 15-20K
FT AGL THROUGH 05/01Z BECOMING SCT THRU THE REMAINDER OF THE
FORECAST PERIOD. SFC WINDS ELY/SELY 8-12 KTS GUSTING 15-20 KTS
THROUGH THIS AFTERNOON, INCREASING TO 15-20 KTS WITH GUSTS TO
30-35 KTS OVERNIGHT AND PERSISTING INTO SUNDAY. THE STRONGEST
WINDS WILL IMPACT TERMINALS EAST OF KTUS...INCLUDING KSAD AND
KDUG DURING THE DAY SUNDAY. LOCALIZED 3-5SM VSBY IN -BLDU WILL
BE POSSIBLE ACROSS THE GILA RIVER AND SAN SIMON VALLEYS
(INCLUDING KSAD) NEAR THE ARIZONA/NEW MEXICO STATE LINE SUNDAY
WITH REDUCTIONS TO SLANT RANGE VISIBILITY POSSIBLE. AVIATION
DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
FIRE WEATHER
WARM AND DRY THIS WEEKEND. A BACKDOOR SURFACE
FRONT WILL BEGIN TO NUDGE INTO THE REGION FROM NEW MEXICO TONIGHT,
RESULTING IN 20-FOOT WINDS FROM THE EAST/SOUTHEAST 15 TO 25 MPH
WITH GUSTS TO 35-40 MPH. THESE WINDS WILL BE CAPABLE OF KICKING
UP SOME LOCALIZED BLOWING DUST, ESPECIALLY ACROSS THE UPPER GILA
RIVER AND SAN SIMON VALLEYS NEAR THE ARIZONA AND NEW MEXICO
STATE LINE. A MINOR MOISTURE INCREASE ALONG THIS FRONT AND A
PASSING WEATHER DISTURBANCE ALOFT WILL RESULT IN A A SLIGHT
(10-20% CHANCE) OF MAINLY MOUNTAIN SHOWERS, POSSIBLY WITH AN
EMBEDDED THUNDERSTORM (LESS THAN 10% CHANCE) MONDAY AND TUESDAY.
MINIMUM RH VALUES (PERCENT) IN THE SINGLE DIGITS TO TEENS
TODAY, INCREASING TO THE TEENS TO MID 20S VALLEYS AND MID 20S TO
MID 40S MOUNTAINS BOTH SUNDAY AND MONDAY. THE HIGHEST MINIMUM
RHS WILL BE EAST OF TUCSON.
TWC WATCHES/WARNINGS/ADVISORIES
NONE.
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