Flash Flooding in Arizona, July 15, 2014

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
930 AM MST TUE JUL 15 2014

.SYNOPSIS...ONE MORE ACTIVE THUNDERSTORM DAY ACROSS SOUTHEAST
ARIZONA BEFORE MOISTURE VALUES START TO LOWER WEDNESDAY THROUGH
FRIDAY. WET STORMS TODAY WITH LOCALIZED FLOODING A CONCERN. DRIER
AIR WILL LIMIT THUNDERSTORM ACTIVITY THURSDAY AND FRIDAY TO THE
HIGHER TERRAIN EAST OF TUCSON. MOISTURE STARTS TO RETURN TO THE AREA
OVER THE WEEKEND INTO EARLY NEXT WEEK FOR AN INCREASE IN
THUNDERSTORMS AGAIN. DAYTIME TEMPERATURES WILL SLOWLY WARM TO A
LITTLE ABOVE AVERAGE AS THE WEEK PROGRESSES.

&&

.DISCUSSION...VERY WET ATMOSPHERE WITH WEAK REMNANT MCC CIRCULATION
SHIFTING FROM COCHISE INTO EASTERN PIMA COUNTY. MID LEVEL FLOW IS
PROBABLY A LITTLE BETTER AT THIS POINT THAN WHAT WAS SHOWING ON THE
12Z SOUNDING. BOTTOM LOADED HEAVY RAIN TYPE STORMS. NOT AS MUCH A
THREAT FOR SEVERE...BUT A LOT OF MOMENTUM WITH WET MICROBURST
POSSIBLE.

SOME CLEARING ALREADY IN EASTERN AREAS INCLUDING MUCH OF COCHISE
COUNTY. THEY WILL REFIRE THIS AFTERNOON. WE WILL NEED TO WATCH FOR
OUTFLOW ACTIVITY LATER IN THE DAY AND THIS EVENING BACK INTO THE
CURRENTLY ACTIVE AREAS. FLASH FLOOD WATCH A CONSIDERATION.

&&

.PREV DISCUSSION...WEDNESDAY IS A TRANSITION DAY AS PW VALUES START
TO FALL ACROSS THE AREA. HOWEVER STILL LOOKING AT SCATTERED STORMS
MAINLY FROM TUCSON EAST. FOR THURSDAY AND FRIDAY...MODELS INDICATING
THAT PW VALUES WILL BE LESS THAN ONE INCH AREA WIDE. THAT WOULD
LIMIT ANY THUNDERSTORM THREAT TO THE HIGHER TERRAIN EAST OF TUCSON.
WHILE THE AREA DRYS OUT A BIT...HIGH TEMPERATURES WILL SLOWLY WARM
TO SEVERAL DEGREES ABOVE NORMAL. ITS BEEN OVER A 10 DAYS WEEK SINCE
TUCSON HAS RECORDED AN ABOVE NORMAL HIGH.

MOISTURE STARTS TO RETURN TO THE AREA OVER THE UPCOMING WEEKEND INTO
EARLY NEXT WEEK AS FLOW ALOFT BECOMES SELY. THUS EXPECT AN INCREASE
IN THUNDERSTORMS CHANCES.

THE MIDDLE PART OF NEXT WEEK...WHICH IS OUTSIDE OF THIS FORECAST
CYCLE PACKAGE...LOOKS DOWN RIGHT HOT WITH BOTH GFS ON TUE AND ECMWF
ON WED...BASED ON 850-700 MB THICKNESS...HINTING AT 110 IN TUCSON.
STAY TUNED.

&&

.AVIATION...SCT SHOWER/TSTM ACTIVITY TODAY INTO THIS EVENING. STORMS
BECOMING NUMEROUS LATE THIS AFTERNOON INTO THE EARLY EVENING
HOURS. LOCAL MVFR/IFR CIGS/VSBYS/MT OBSCURATIONS WITH GUSTS TO 35-45
KTS IN THE VICINITY OF TSRA. AFT 16/05Z STORMS BECMG ISOLD.
OTHERWISE...SFC WIND GENERALLY 15 KTS OR LESS. AVIATION DISCUSSION
NOT UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...ANOTHER ACTIVE THUNDERSTORM DAY IS FORECASTED
TODAY...WITH THE POTENTIAL FOR HEAVY RAIN AND STRONG WINDS. EXPECT
STRONG...GUSTY AND ERRATIC WINDS WITH ANY OF THE THUNDERSTORMS. A
SIGNIFICANT DROP IN THUNDERSTORM CHANCES ARE EXPECTED DURING THE
LATTER PART OF THE WEEK WITH WARMER TEMPERATURES AND LOWER RELATIVE
HUMIDITY VALUES AS THE UPPER LEVEL HIGH MOVES OVER THE AREA.
THUNDERSTORM CHANCES SHOULD PICK BACK UP AGAIN DURING THE WEEKEND
AND EARLY NEXT WEEK.

&&

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

&&

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