Area Forecast Discussion
Issued by NWS Tucson, AZ

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS65 KTWC 260919
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
218 AM MST FRI SEP 26 2014

.SYNOPSIS...THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL INCREASE
THROUGH SATURDAY AS A FRONT APPROACHES THE AREA FROM THE NORTHWEST.
THERE IS AN INCREASED RISK FOR STRONGER AND WETTER STORMS OVER THE
WEEKEND...ESPECIALLY SATURDAY. DRIER AND COOLER NEXT WEEK AS THE
MONSOON SEASON COMES TO A CLOSE.

&&

.DISCUSSION...THE MAIN FOCUS WILL BE ON A STORM SYSTEM FORECAST TO
ENTER THE GREAT BASIN REGION ON SATURDAY. MODELS CONTINUED TO SHOW
MOISTURE INCREASING IN ADVANCE OF THIS SYSTEM ACROSS MUCH OF
ARIZONA. ALREADY SAW A SLIGHT INCREASE IN MOISTURE YESTERDAY WHICH
WAS ENOUGH TO SUPPORT SOME THUNDERSTORMS IN THE AFTERNOON AND
EVENING. A LITTLE MORE MOISTURE TODAY FOR A SLIGHT INCREASE IN
THUNDERSTORM ACTIVITY COMPARED TO YESTERDAY. OTHERWISE...THE
SIGNIFICANT INCREASE IN SHOWERS AND THUNDERSTORMS WILL COME ON
SATURDAY AS THE STORM SYSTEM ENTERS THE GREAT BASIN AND INTERACTS
WITH MOISTURE ACROSS ARIZONA. RATHER COMMON PATTERN AND SCENARIO FOR
SEVERE THUNDERSTORMS ACROSS PORTIONS OF ARIZONA...ESPECIALLY CENTRAL
AND NORTHERN SECTIONS OF THE STATE. WILL LIKELY SEE SOME STRONG
THUNDERSTORMS ACROSS OUR CWA...BUT THE BEST UPPER LEVEL DYNAMICS
WILL BE NORTH OF THE AREA. AT ANY RATE...WILL INTRODUCE AREAS OF
BLOWING DUST IN PARTS OF PIMA AND PINAL COUNTIES FOR SATURDAY
AFTERNOON AND EARLY EVENING DUE TO GRADIENT AND THUNDERSTORM WINDS.
MODELS TRACK THE SYSTEM THROUGH THE CENTRAL ROCKIES BY MONDAY WITH
MUCH DRIER AIR SPREADING INTO THE REGION BEHIND THE STORM. THAT
SAID...EXPECTING A TIMELY ENDING TO THE MONSOON SEASON ALONG WITH
COOLER TEMPERATURES NEXT WEEK.

&&

.AVIATION...VALID THRU 27/12Z.
FEW-SCT CLOUDS AT 8-12K FT AGL THRU 26/19Z...MAINLY EAST OF A KFHU
TO KSAD LINE...OTHERWISE SKC CONDITIONS. SCT-BKN CLOUDS AT 6-10K FT
AGL DEVELOPING AFT 26/19Z AND PERSISTING TIL 27/05Z. DECREASING
CLOUDS EXPECTED AFT 27/05Z. ISOLATED TO SCATTERED SHRA/TSRA AFT
26/20Z...MAINLY IN THE HIGHER TERRAIN NORTHEAST OF KTUS...AND ALSO
SOUTH/SOUTHWEST OF KTUS. THE BULK OF THESE SHOWERS/THUNDERSTORMS
WILL END AROUND 27/04Z FOLLOWED BY ISOLATED -SHRA/-TSRA LATE
TONIGHT/SATURDAY MORNING. MORE NUMEROUS SHRA/TSRA COVERAGE IS THEN
EXPECTED SATURDAY AFTERNOON/EVENING. WIND GUSTS TO NEAR 45 KTS
POSSIBLE WITH THE STRONGER THUNDERSTORMS. OTHERWISE...SURFACE WIND
GENERALLY LESS THAN 10 KTS THRU 27/12Z. AVIATION DISCUSSION NOT
UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...THERE WILL BE INCREASING CHANCES OF SHOWERS AND
THUNDERSTORMS TODAY AND SATURDAY ACROSS ALL OF SOUTHEAST ARIZONA...
WITH LINGERING PRECIPITATION CHANCES OVER THE EASTERN HALF OF THE
FORECAST AREA ON SUNDAY. MUCH DRIER CONDITIONS ARE THEN EXPECTED
NEXT WEEK AS THE 2014 MONSOON SEASON COMES TO AN END. THE STRONGER
THUNDERSTORMS MAY PRODUCE SOME GUSTY OUTFLOW WINDS. OTHERWISE...
20-FOOT WINDS WILL BE LESS THAN 15 MPH TODAY...AND SOUTHWEST AT 10
TO 20 MPH SATURDAY AND SUNDAY AFTERNOON.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON






USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.