953
FXUS65 KTWC 052131
AFDTWC
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
231 PM MST MON MAY 5 2025
SYNOPSIS
A STRONG PACIFIC WEATHER SYSTEM WILL BRING COOLER
TEMPERATURES OVER THE COMING DAYS WITH PERIODIC CHANCES FOR
SCATTERED SHOWERS...POSSIBLY WITH AN EMBEDDED THUNDERSTORM. LIGHTER
WINDS WITH AFTERNOON BREEZES TODAY AND TUESDAY. TEMPERATURES WILL
THEN REBOUND THE SECOND HALF OF NEXT WEEK, WITH THE POSSIBILITY FOR
THE CENTURY MARK RETURNING NEXT WEEKEND.
DISCUSSION
CLOUD COVERAGE HAS BEEN INCREASING, ESPECIALLY OVER
PIMA AND PINAL COUNTIES THANKS TO A STRONG PACIFIC STORM SYSTEM
MOVING OVERHEAD. THE CENTER OF THE LOW, NOW LOCATED OVER SOUTH
CENTRAL ARIZONA, HAS DRIFTED FURTHER SOUTH THAN PREVIOUS GUIDANCE
SUGGESTED AS THE TROUGH CONTINUES TO DIG INTO CENTRAL MEXICO. THIS
PLACES SOUTHEAST ARIZONA UNDER THE STRONGER SYNOPTIC LIFT ASSOCIATED
WITH A THE CENTER OF THE LOW IN ADDITION TO A SERIES OF DISTURBANCES
ROTATING AROUND THE SYSTEM.
MINIMAL INSTABILITY ACROSS THE AREA TODAY (UP TO 500 J/KG) COMBINED
WITH FAVORED DYNAMIC LIFT IN CONJUNCTION WITH THE UPPER LOW WILL
SUPPORT LOW CHANCES FOR EMBEDDED THUNDERSTORMS MAINLY ACROSS
PORTIONS OF PIMA, PINAL, GRAHAM, AND GREENLEE COUNTIES THIS
AFTERNOON. QUESTION WILL BE HOW MUCH RAIN COULD WE SQUEAK OUT FROM
THIS ACTIVITY IN ADDITION TO A SECOND ROUND OF PRECIPITATION LATE
TONIGHT INTO EARLY TOMORROW MORNING OVER PINAL, GRAHAM, AND GREENLEE
COUNTIES. HREF MEAN 24-HR QPF SUGGESTS BETWEEN 0.1" TO 0.3" WITH THE
HIGHER AMOUNTS EXPECTED OVER PINAL, GRAHAM, GREENLEE, CENTRAL PIMA
COUNTIES. MOISTURE CONTENT WILL KEEP THE SNOWFALL ACROSS THE HIGHEST
ELEVATIONS AT BAY, BUT STORM TOTAL SNOWFALL AMOUNTS BETWEEN 3-5
INCHES WILL BE POSSIBLE IN HANNAGAN MEADOW.
TOMORROW THE LOW WILL ADVANCE TO THE EAST INTO NEW MEXICO, BUT
LINGERING CHANCES FOR LIGHT SHOWERS WILL CONTINUE THROUGH LATE
WEDNESDAY AS ANOTHER UPPER LOW MOVES OUT OF THE GREAT BASIN AND
SWEEPS THROUGH THE AREA. HOWEVER, THE HEAVIEST PRECIPITATION
ASSOCIATED WITH THIS SYSTEM SHOULD TRACK OVER NORTHERN ARIZONA
BRINGING MEDIUM CHANCES FOR
MID-LEVEL RIDGING WILL LEAD TO A SHARP AND SUDDEN INCREASE IN
TEMPERATURES THURSDAY THROUGH SATURDAY WITH THE POTENTIAL TO SEE
HIGH TEMPERATURES SURPASS THE 100 DEGREE MARK.
AVIATION
VALID THROUGH 07/00Z.
WIDESPREAD CUMULUS AT 7K-10K FEET THIS AFTERNOON WITH LOWER CLOUD
DECKS OF 4K-7K FT WITH SCATTERED SHOWERS. MOUNTAIN OBSCURATIONS WITH
LOWER VISIBILITIES LIKELY WITH THESE LOWER CLOUDS AND SHOWERS AS
WELL. ISOLATED LIGHTNING THROUGH THE EARLY EVENING. SOUTHWESTERLY
WINDS 12-17 KTS WITH GUSTS TO 25 KTS THROUGH 06/02Z, WITH WINDS ON
THE STRONGER SIDE OF THAT IN THE FAR SE, NEAR KDUG. WINDS BECOME
LIGHT AND TERRAIN DRIVEN AFTER 06/02Z. ISOLATED TO SCATTERED SHOWERS
POSSIBLE THROUGH THE REMAINDER OF THE TAF PERIOD. AVIATION
DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
FIRE WEATHER
ISOLATED TO SCATTERED SHOWERS CONTINUE THROUGH
TUESDAY WITH UNSEASONABLY COOL TEMPERATURES AND MINIMUM RELATIVE
HUMIDITIES ABOVE 25 PERCENT. BREEZY WINDS TODAY IN FAR SE ARIZONA
DIMINISH WITH WINDS GENERALLY REMAINING LIGHT AND UNDER 15 MPH OVER
COMING SEVERAL DAYS. A WARMING AND DRYING TREND IS EXPECTED FOR THE
SECOND HALF OF THE WEEK.
TWC WATCHES/WARNINGS/ADVISORIES
NONE.
PUBLIC...DVS
AVIATION...EDWARDS
FIRE WEATHER....EDWARDS
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page