Flash Flood Warning 47, NWS Tucson, AZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
915 PM MST MON AUG 18 2014

.SYNOPSIS...AMPLE MOISTURE WILL PROVIDE SCATTERED TO NUMEROUS
THUNDERSTORMS THROUGH MIDWEEK. SOME STORMS WILL PRODUCE GUSTY WINDS
AND HEAVY RAINFALL. A VERY MODEST DRYING TREND WILL THEN OCCUR
DURING THE LATTER PART OF THE WEEK AND INTO THIS WEEKEND. HOWEVER...
ENOUGH MOISTURE WILL EXIST FOR ISOLATED TO SCATTERED THUNDERSTORMS.
BELOW NORMAL DAYTIME TEMPERATURES WILL PREVAIL THROUGH WEDNESDAY
FOLLOWED BY A GRADUAL WARMING TREND LATER THIS WEEK.

&&

.DISCUSSION...ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS
CONTINUED LATE THIS EVENING. NEW DEVELOPMENT HAS BEEN FOCUSED OVER
THE FOOTHILLS OF THE CATALINA AND RINCON MOUNTAINS WERE VERY HEAVY
RAINFALL WILL BE A CONCERN THROUGH MIDNIGHT TONIGHT. RECENT RADAR
IMAGERY WAS ALSO SHOWING SOME DEVELOPMENT ACROSS EASTERN SECTIONS OF
THE TUCSON AREA GENERALLY ALONG HOUGHTON ROAD. NEEDLESS TO SAY...THE
THUNDERSTORM ACTIVITY WAS NOT OVER WITH FOR THE NIGHT. IN FACT...IT
APPEARED THAT IT WAS JUST GETTING STARTED FOR MUCH OF EASTERN PIMA
COUNTY. AT ANY RATE...CURRENT FORECAST KEEPS POP VALUES UP FOR
OVERNIGHT SO NO ADJUSTMENTS NECESSARY. PLEASE REFER TO THE
ADDITIONAL SECTIONS FOR MORE DETAILS.

&&

.AVIATION...VALID THRU 20/06Z.
EXPECT SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS THROUGH
TUESDAY AFTERNOON. MVFR VISIBILITIES AND BRIEF WIND GUSTS OF 45-50
KTS WILL OCCUR WITH THE STRONGER TSRA. OTHERWISE...CLOUD DECKS WILL
MAINLY BE AT 6-12K FT AGL AND SURFACE WIND WILL GENERALLY BE LESS
THAN 10 KTS THRU TUESDAY AFTERNOON. AVIATION DISCUSSION NOT UPDATED
FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...SCATTERED TO NUMEROUS THUNDERSTORMS WILL OCCUR
THROUGH WEDNESDAY AS AMPLE MOISTURE REMAINS ACROSS SOUTHEAST
ARIZONA. THE STRONGER THUNDERSTORMS WILL PRODUCE STRONG...GUSTY AND
ERRATIC WINDS. EXPECT SOMEWHAT LESS COVERAGE OF THUNDERSTORMS DURING
THE LATTER PART OF THE WEEK AND NEXT WEEK. HOWEVER...MOISTURE WILL
BE SUFFICIENT TO PROVIDE ISOLATED TO SCATTERED MAINLY AFTERNOON AND
EVENING THUNDERSTORMS. OTHERWISE...20-FOOT WINDS WILL EXHIBIT NORMAL
DIURNAL TRENDS AND BE MOSTLY LESS THAN 15 MPH.

&&

.PREV DISCUSSION...HIGH PRESSURE ALOFT CENTERED OVER NWRN NEW MEXICO
THIS AFTERNOON WILL BECOME POSITIONED OVER THE LOWER MISSISSIPPI
RIVER VALLEY REGION BY WED AS A CLOSED UPPER LOW DEVELOPS OVER SRN
CALIFORNIA. A STRONGLY DIFFLUENT FLOW ALOFT REGIME IN COMBINATION
WITH AMPLE MOISTURE SHOULD ENHANCE COVERAGE OF SHOWERS/TSTMS LATER
TONIGHT INTO TUE. POPS WERE INCREASED TO DEPICT SCATTERED TO
NUMEROUS COVERAGE OF SHOWERS/TSTMS BY TUE AFTERNOON.

THERE IS STILL SOME UNCERTAINTY REGARDING THE EXACT PERIOD FOR THE
HEAVIEST RAINFALL TO OCCUR. ALTHOUGH STORM MOTIONS MAY BE RELATIVELY
FAST...THE PROGGED PATTERN SUGGESTS THAT TRAINING STORMS THAT WOULD
ENHANCE HEAVY RAINFALL MAY OCCUR. AT ANY RATE...HAVE DEFERRED A
POTENTIAL FLASH FLOOD WATCH ISSUANCE TO SUBSEQUENT SHIFTS. SOMEWHAT
LESS COVERAGE OF SHOWERS/TSTMS SHOULD OCCUR WED VERSUS TUE.
HOWEVER...CONTINUED AMPLE MOISTURE IN COMBINATION WITH A SOMEWHAT
DIFFLUENT FLOW ALOFT REGIME AHEAD OF THE SRN CALIFORNIA UPPER LOW
WILL PROVIDE SCATTERED SHOWERS/TSTMS ACROSS MUCH OF SE AZ.

18/12Z GFS/ECMWF WERE SIMILAR WITH SHUNTING THE DEEPER MOISTURE EWD
INTO WRN NEW MEXICO THUR AS THE SRN CALIFORNIA UPPER LOW BEGINS TO
MERGE WITH THE NRN STREAM TROUGH. A VERY GRADUAL DRYING TREND IS
PROGGED TO OCCUR FRI-SAT UNDER LIGHT GENERALLY WLY FLOW ALOFT.
GFS/ECMWF WERE SIMILAR WITH DEPICTING INCREASED MOISTURE SUN AS THE
MID-LEVEL FLOW BECOMES ELY AND A WEAK UPPER LOW APPROACHES FROM THE
SOUTH. THE UPSHOT FOR THUR-SUN...ENOUGH MOISTURE WILL EXIST FOR
ISOLATED TO SCATTERED MAINLY AFTERNOON AND EVENING SHOWERS/TSTMS.

HIGH TEMPS TUE-WED ARE FORECAST TO AVERAGE ABOUT 5-8 DEGS F OR SO
BELOW NORMAL. A WARMING TREND IS ON TAP DURING THE LATTER PART OF
THE WEEK...WITH DAYTIME TEMPS RETURNING CLOSE TO NORMAL THIS
UPCOMING WEEKEND.

&&

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

&&

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

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TUCSON AZ
534 PM MST MON AUG 18 2014

AZZ507-513-190115-
DRAGOON/MULE/HUACHUCA AND SANTA RITA MOUNTAINS INCLUDING
BISBEE/CANELO HILLS/MADERA CANYON AZ-UPPER SAN PEDRO RIVER VALLEY
INCLUDING SIERRA VISTA/BENSON AZ-
534 PM MST MON AUG 18 2014

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN COCHISE COUNTY UNTIL
615 PM MST...

AT 525 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM IN SIERRA VISTA.  THIS STORM WAS NEARLY
STATIONARY.

HAIL UP TO ONE-HALF INCH IN DIAMETER AND WIND GUSTS UP TO 40 MPH ARE
EXPECTED WITH THIS STORM...ALONG WITH HEAVY RAIN.

AREAS AFFECTED BY THIS STORM INCLUDE...HUACHUCA CITY...CHARLESTON AND
FORT HUACHUCA.

LAT...LON 3175 11023 3157 11004 3144 11026 3158 11040
TIME...MOT...LOC 0034Z 180DEG 0KT 3159 11021