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000
FXUS65 KTWC 281629
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
915 AM MST MON JUL 28 2014

.SYNOPSIS...WE STILL HAVE ENOUGH MOISTURE IN PLACE FOR A CHANCE OF
SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND EVENING. SOME STORMS
WILL GENERATE LOCALLY HEAVY RAINFALL. FEWER STORMS ARE EXPECTED
AROUND MID WEEK AS HIGH PRESSURE BUILDS OVERHEAD ACCOMPANIED BY
SEVERAL DEGREES OF HEATING BY TUESDAY OR WEDNESDAY. A STRONGER
CHANCE OF THUNDERSTORMS RETURNS ONCE AGAIN TO END THE WEEK AND TAKE
US INTO NEXT WEEKEND.

&&

.DISCUSSION...ANOTHER NIGHT OF WIDESPREAD SHOWER AND THUNDERSTORM
ACTIVITY WITH REMNANT MCV NOW JUST NORTH OF GRAHAM AND GREENLEE
COUNTIES DRIFTING OUT OF OUR AREA. THIS WILL TEND TO RETARD INITIAL
STORM DEVELOPMENT BEHIND THIS FEATURE FOR SEVERAL HOURS. ANOTHER
STRONG COMPLEX SOUTH OF DOUGLAS BUT THE MOST ACTIVE AREA TENDING TO
BE ON THE SOUTHWEST FLANK WITH THE MEAN FLOW. 12Z KTWC SOUNDING HAS
GREAT MOISTURE AT 1.57 INCHES PRECIPITABLE WATER...VERY CONSISTENT
WITH VALUES ON BLENDED SATELLITE ESTIMATES RANGING FROM 1.35 IN FAR
EASTERN AREAS TO 1.7 IN WESTERN AREAS. HOWEVER POOR MID LEVEL WIND
PROFILE FOR DEVELOPING GOOD STORM STRUCTURE AND LIMITED SHEAR. WE
WON`T BE SHUT DOWN BUT COVERAGE WILL PROBABLY BE LESS THAN WE HAD
BEEN ADVERTISING WITH AN EMPHASIS ON AREAS SOUTH AND EAST OF TUCSON.
STORMS WILL BE SLOW MOVERS...TENDING TO PROPAGATE ON OUTFLOWS AND
SLOW NEW DEVELOPMENT INTO MOST FAVORABLE NEAR STORM ENVIRONMENT
POCKETS. WHATEVER STORMS WE DO GET WILL BE VERY WET.

&&



.AVIATION...VALID THRU 29/16Z.
A FEW -TSRA/-SHRA WILL OCCUR MAINLY NEAR THE MOUNTAINS EAST OF KTUS
THIS MORNING...THEN SCATTERED TSRA/SHRA THIS AFTERNOON INTO THIS
EVENING. MVFR CONDITIONS WILL OCCUR WITH THE STRONGER TSRA ALONG
WITH WIND GUSTS TO AROUND 45 KTS. CLOUD DECKS WILL GENERALLY BE AT
7-12K FT AGL INTO TONIGHT. SOME CLEARING TUESDAY MORNING ESPECIALLY
FROM KTUS WESTWARD. AVIATION DISCUSSION NOT UPDATED FOR TAF
AMENDMENTS.

&&

.FIRE WEATHER...SCATTERED THUNDERSTORMS WILL OCCUR THIS AFTERNOON
AND EVENING. EXPECT STRONG...GUSTY AND ERRATIC WINDS ASSOCIATED WITH
THE STRONGER STORMS. DRIER CONDITIONS WILL THEN PROVIDE DECREASED
THUNDERSTORM ACTIVITY TUESDAY THROUGH THURSDAY.
THEREAFTER...SCATTERED MOSTLY AFTERNOON AND EVENING THUNDERSTORMS
WILL PREVAIL FRIDAY THROUGH SUNDAY AS DEEPER MOISTURE RETURNS TO THE
AREA. OTHERWISE...NORMAL DIURNAL WIND TRENDS WILL OCCUR WITH
OCCASIONAL GUSTS DURING THE AFTERNOON HOURS DUE TO DAYTIME HEATING.

&&

.PREV DISCUSSION...
TUE-THUR...
28/00Z GFS/ECMWF WERE SIMILAR WITH DEPICTING A DRYING TREND AS WLY/
NWLY MID-LEVEL IS PROGGED TO OCCUR. THE LEAST COVERAGE OF SHOWERS/
TSTMS SHOULD OCCUR WED ASSUMING THE GFS/ECMWF SOLUTIONS TO BE
REALITY.

FRI-SUN...
GFS/ECWMF WERE SIMILAR WITH DEPICTING INCREASING MOISTURE ACROSS SE
AZ AS THE UPPER HIGH BECOMES CENTERED NEAR THE FOUR CORNERS REGION.
HAVE NOTED THAT THESE SOLUTIONS HAVE DEPICTED REDUCED QPF/S...
PARTICULARLY THIS WEEKEND...VERSUS GFS/ECMWF SOLUTIONS FROM 24 HOURS
AGO. AT ANY RATE...FORECAST CONFIDENCE IS FAIRLY HIGH THAT DEEPER
MOISTURE WILL LEAD TO SCATTERED MAINLY AFTERNOON AND EVENING SHOWERS/
TSTMS.

HIGH TEMPS THIS AFTERNOON WILL GENERALLY BE SIMILAR TO TEMPS
ACHIEVED SUN AFTERNOON. A WARMING TREND WILL THEN OCCUR TUE-WED
FOLLOWED BY A MODERATION IN DAYTIME TEMPS BY THIS WEEKEND.

&&

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

&&

$$

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