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 292121
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
220 PM MST FRI AUG 29 2014

.SYNOPSIS...MOSTLY CLEAR...HOT AND DRY CONDITIONS WILL CONTINUE
THROUGH THE HOLIDAY WEEKEND.  THEN...SOME MOISTURE WILL SNEAK INTO
AREAS NEAR THE INTERNATIONAL BORDER FOR A SLIGHT CHANCE OF
THUNDERSTORMS TUESDAY AND WEDNESDAY.  THE MOISTURE IS EXPECTED TO
BECOME MORE PRONOUNCED LATE IN THE WEEK WITH AN INCREASE IN SHOWER
AND THUNDERSTORM ACTIVITY.

&&

.DISCUSSION...HOT AND DRY THROUGH THE WEEKEND THANKS TO HIGH
HEIGHTS/THICKNESSES AND A DRY AIR MASS OVER THE REGION.  HIT 100 SO
FAR AT TUCSON WHICH IS THE FIRST TIME SINCE THE 16TH AND WITH
THICKNESSES INCREASING SATURDAY WOULD EXPECT 2-3 DEGREES WARMER YET
AREAWIDE AND THEN A DEGREE OR SO COOLER OVERALL SUNDAY AND MONDAY.

THE UPPER LEVEL HIGH CURRENTLY OF THE CALIFORNIA COAST WILL BUILD
EAST LATE THIS WEEKEND AND SET UP JUST TO OUR EAST MONDAY THEN
GRADUALLY CONTINUE EAST THROUGH THE WEEK.  THIS WILL BEGIN TO ALLOW
SOME MOISTURE TO ADVECT NEARBY MONDAY THEN OVER SOUTHEAST PORTIONS
OF THE FORECAST AREA TUESDAY AND WEDNESDAY RESULTING IN A THREAT OF
CONVECTION SOUTHEAST PART OF THE AREA THOSE TWO DAYS.  SHOULD ALSO
SEE AFTERNOON HIGH TEMPERATURES COOLING A DEGREE OR TWO AS WELL.

BEYOND THAT...THE QUESTION BECOMES HOW MUCH MOISTURE DO WE GET OVER
THE AREA.  WHILE DETAILS DIFFER WHICH IS USUAL...MID RANGE MODEL
FIELDS CONTINUE TO INDICATE A NICE FETCH OF MOISTURE MOVING INTO THE
REGION ON SOUTHEAST FLOW.  OVER THE LAST FEW DAYS THE EC HAS BEEN
THE MOST CONSISTENT WITH THIS SCENARIO AND WOULD RAMP UP THE
MOISTURE THURSDAY AND ESPECIALLY FRIDAY INTO SATURDAY RESULTING IN
AN UPTICK IN CONVECTION ACROSS THE AREA.  HAVE LEANED ON THAT IDEA
AND TWEAKED THE FORECAST BY ADJUSTING TO POPS UPWARD BY AT LEAST
BRINGING THEM UP CLIMATOLOGY FOR THE EARLY PART OF SEPTEMBER.  WITH
THE IDEA OF MORE CLOUDS AND POTENTIAL SHOWERS I ALSO TWEAKED
AFTERNOON TEMPS DOWN A BIT AS WELL.  WILL HAVE TO SEE HOW THIS ALL
PANS OUT.  CERNIGLIA

&&

.AVIATION...VALID THRU 31/00Z.
EXPECT A FEW CUMULUS CLOUDS WITH BASES AROUND 8-12K FT AGL INTO THE
EVENING HOURS AND AGAIN SATURDAY AFTERNOON AND EARLY
EVENING...OTHERWISE SKIES WILL BE CLEAR.  SURFACE WINDS WILL BE
MAINLY LESS THAN 10 KTS THRU SATURDAY...EXCEPT FOR OCCASIONAL GUSTS
TO AROUND 20 KTS DURING THE MID TO LATE AFTERNOON HOURS.  AVIATION
DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.  CERNIGLIA

&&

.FIRE WEATHER...DRY CONDITIONS WILL PREVAIL THROUGH MONDAY WITH
WARMER THAN NORMAL TEMPERATURES AND LOWER THAN NORMAL HUMIDITY
LEVELS.  THE UPPER LEVEL HIGH WILL REPOSITION ITSELF EAST EARLY NEXT
WEEK TO WHERE MOISTURE IS EXPECTED TO MOVE INTO SOUTHEAST PARTS OF
THE AREA FOR A SLIGHT CHANCE OF THUNDERSTORMS MAINLY NEAR THE
INTERNATIONAL BORDER SOUTH TO SOUTHEAST OF TUCSON TUESDAY.  THE
MOISTURE WILL LIKELY SPREAD A BIT WEDNESDAY AND MORE SO THURSDAY
THROUGH FRIDAY FOR INCREASING CHANCES OF CONVECTION.  EXPECT LIGHT
TERRAIN DRIVEN WINDS INTO EARLY NEXT WEEK.  GUSTY OUTFLOWS
ASSOCIATED WITH THUNDERSTORMS WILL THEN OCCUR DURING THE LATTER PART
OF NEXT WEEK.  CERNIGLIA

&&

.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.