800
FXUS65 KTWC 021925
AFDTWC
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
1225 PM MST SAT MAY 2 2026
SYNOPSIS
A PACIFIC STORM SYSTEM WILL APPROACH THE REGION THROUGH
EARLY NEXT WEEK, CROSSING THE REGION BY MID-WEEK. BREEZY WINDS ARE
EXPECTED MONDAY AND TUESDAY WITH THIS SYSTEM, AS WELL AS A CHANCE OF
SHOWERS AND THUNDERSTORMS LATE MONDAY AFTERNOON THROUGH TUESDAY
NIGHT. HIGH TEMPERATURES WILL BE SEVERAL DEGREES ABOVE NORMAL
SUNDAY, AROUND NORMAL ON MONDAY, FALLING BELOW NORMAL TUESDAY AND
WEDNESDAY AND THEN RISING BACK ABOVE NORMAL THE LATTER HALF OF NEXT
WEEK.
DISCUSSION
EAST-SOUTHEAST WINDS HAVE SLACKENED FROM EARLIER
SPEEDS, WITH WINDS SPEEDS OF 10-15 MPH AND GUSTS TO 20-25 MPH
EXPECTED THROUGH THE MID MORNING HOURS ON SUNDAY. A WEAK DISTURBANCE
LOCATED ALONG THE NORTHERN ARIZONA/NEW MEXICO STATE LINE WILL
CONTINUE TO PUSH SOUTH TODAY BEFORE SHIFTING EASTWARD TONIGHT. THIS
FEATURE WILL BRING A CHANCE OF SHOWERS AND THE POTENTIAL FOR A FEW
THUNDERSTORMS TO THE WHITE MOUNTAINS THROUGH THE EVENING HOURS
TONIGHT. OTHERWISE, HIGH TEMPERATURES TODAY WILL TOP OUT A DEGREE OR
TWO ABOVE NORMAL.
AN UPPER LOW CURRENTLY CENTERED OFF THE NORTHERN CALIFORNIA/SOUTHERN
OREGON COAST WILL CONTINUE TO MOVE SOUTH ALONG THE CALIFORNIA COAST
ON SUNDAY. THE CLOSED LOW WILL MOVE INLAND INTO CENTRAL CALIFORNIA
MONDAY AND THEN SAG SOUTHWARD INTO SOUTHERN CALIFORNIA EARLY TUESDAY
BEFORE EJECTING NORTHEAST AS AN OPEN WAVE ACROSS NORTHERN ARIZONA
LATE TUESDAY INTO EARLY WEDNESDAY.
AS THE ABOVE MENTIONED SYSTEM SLIDES DOWN THE CALIFORNIA COAST ON
SUNDAY IT WILL RESULT IN A VERY SLIGHT CHANCE OF SHOWERS SUNDAY
AFTERNOON/EARLY EVENING TO THE EAST OF TUCSON AS UPPER DYNAMICS
START TO COME INTO PLAY AND PW VALUES IN THE 0-5"-0.75" RANGE STILL
RESIDE ACROSS EASTERN AREAS. AS THE UPPER LOW MOVES CLOSER TO THE
REGION MONDAY AND TUESDAY, IT WILL TAP INTO A SUBTROPICAL MOISTURE
PLUME WHICH THEN GETS PULLED NORTHEASTWARD OUT AHEAD OF THE LOW
ACROSS SOUTHEAST ARIZONA. POPS ARE GENERALLY IN THE 20-40 PERCENT
RANGE FROM LATE MONDAY AFTERNOON THROUGH EARLY TUESDAY WITH THIS
FEATURE. THE HIGHEST POPS (40-60 PERCENT) OCCUR TUESDAY AFTERNOON
AND EVENING AS THE LOW TRACKS ACROSS NORTHERN ARIZONA. RAINFALL
TOTALS WITH THIS SYSTEM WILL GENERALLY BE LIGHT, AND MAINLY FROM
TUCSON EASTWARD, WITH AMOUNTS FROM A COUPLE OF HUNDREDTHS TO A TENTH
OF AN INCH IN THE VALLEYS AND A TENTH TO A QUARTER OF AN INCH IN THE
NORTHERN SKY ISLANDS/WHITE MOUNTAINS. ISOLATED AMOUNTS UP TO ONE
HALF INCH WILL BE POSSIBLE WITH ANY THUNDERSTORMS THAT DEVELOP.
WINDS WILL BE ON THE INCREASE MONDAY AS THE UPPER LOW APPROACHES THE
REGION, WITH SOUTH-SOUTHWEST WINDS OF 15-20 MPH AND GUSTS TO 30-35
MPH AND THEN SOUTHWEST-WEST WINDS OF 20-25 MPH AND GUSTS TO 35-40
MPH TUESDAY AS THE SYSTEM MOVES TO OUR NORTH. AT THIS TIME, RELATIVE
HUMIDITY LEVELS REMAIN ABOVE ANY CRITICAL FIRE WEATHER THRESHOLDS.
HIGH TEMPERATURES WILL WARM TO 3-5 DEGREES ABOVE NORMAL SUNDAY, TOP
OUT AROUND NORMAL ON MONDAY AND THEN LOWER TO AROUND 10 DEGREES
BELOW NORMAL TUESDAY AND 4-6 DEGREES BELOW NORMAL WEDNESDAY.
DRY CONDITIONS RETURN TO SOUTHEAST ARIZONA BEHIND THE SYSTEM LATE
NEXT WEEK INTO THE FOLLOWING WEEKEND, ALONG WITH HIGH TEMPERATURES
RISING BACK ABOVE NORMAL LEVELS.
AVIATION
VALID THROUGH 04/00Z.
FEW-SCT CLOUDS (LOCALLY BKN IN THE HIGHER TERRAIN) AT 9K-12K FT AGL
MAINLY EAST OF A KCGZ TO KOLS LINE, WITH A SLIGHT CHANCE OF -SHRA IN
THE WHITE MOUNTAINS TO THE NE OF KSAD THRU 03/06Z. INCREASING HIGH
LEVEL CIRRUS CLOUDS THIS AFTERNOON, WITH BKN-OVC CLOUDS AOA 20K FT
AGL AREAWIDE AFT 03/03Z THRU THE REST OF THE VALID PERIOD. SFC WIND
ELY/SELY AT 8-14 KTS THRU 03/18Z. AFT 03/18Z, SFC WIND BECOMING
SLY/SWLY AT 7-14 KTS THRU THE REMAINDER OF THE FORECAST PERIOD.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
FIRE WEATHER
A WEAK DISTURBANCE WILL BRING A SLIGHT CHANCE OF
SHOWERS AND THUNDERSTORMS TO THE WHITE MOUNTAINS THIS EVENING. A
PACIFIC STORM SYSTEM WILL THEN RESULT IN INCREASING SOUTH-SOUTHWEST
WINDS MONDAY AND TUESDAY, ALONG WITH A CHANCE OF SHOWERS AND
THUNDERSTORMS LATE MONDAY AFTERNOON THROUGH TUESDAY NIGHT. 20-FOOT
SOUTH TO SOUTHWEST WINDS OF 15-20 MPH AND GUSTS TO 30-35 MPH ARE
EXPECTED MONDAY, WITH SOUTHWEST TO WEST WINDS OF 20-25 MPH AND GUSTS
TO 35-40 MPH ON TUESDAY. MIN RELATIVE HUMIDITY VALUES WILL BE IN THE
18-23 PERCENT RANGE IN THE LOWER ELEVATIONS TO THE EAST OF TUCSON ON
SUNDAY, WITH VALUES IN THE 10-15 PERCENT RANGE FROM TUCSON WESTWARD.
MIN RH VALUES THEN INCREASE INTO THE 17-27 PERCENT RANGE ACROSS THE
LOWER ELEVATIONS MONDAY, WITH VALUES ABOVE 20 PERCENT ON TUESDAY
(AND EVEN HIGHER VALUES IN THE MOUNTAINS). RELATIVE HUMIDITY LEVELS
DROP BACK INTO THE SINGLE DIGITS THE SECOND HALF OF NEXT WEEK. HIGH
TEMPERATURES WILL BE 3-5 DEGREES ABOVE NORMAL ON SUNDAY, AROUND
NORMAL MONDAY, FALLING BELOW NORMAL TUESDAY AND WEDNESDAY AND THEN
RISING BACK ABOVE NORMAL THE LATTER HALF OF NEXT WEEK.
TWC WATCHES/WARNINGS/ADVISORIES
NONE.
ZELL
VISIT US ON FACEBOOK, X, YOUTUBE, AND AT WEATHER.GOV/TUCSON
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page