Flash Flood Warning 44, NWS Flagstaff, AZ

000 
WGUS75 KFGZ 162324
FFSFGZ

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
422 PM MST THU AUG 16 2007

AZC005-162332-
COCONINO AZ-
422 PM MST THU AUG 16 2007

...THE FLASH FLOOD WARNING WILL EXPIRE AT 430 PM MST FOR NORTH
CENTRAL COCONINO COUNTY...

AT 420 PM MST...FLAGSTAFF DOPPLER RADAR INDICATED THAT RAINFALL HAS 
ENDED ACROSS THE ANTELOPE CREEK DRAINAGE. RADAR INDICATED THAT AS 
MUCH AS AN INCH TO AN INCH AND A HALF OF RAIN MAY HAVE FALLEN IN THE 
DRAINAGE...BUT NO REPORTS OF FLOODING HAVE BEEN RECEIVED. PORTIONS 
OF ANTELOPE CREEK...INCLUDING ANTELOPE CANYON...MAY STILL HAVE 
HIGHER THAN NORMAL FLOW THROUGH THE EARLY EVENING...HOWEVER...THE 
THREAT FOR SIGNIFICANT FLASH FLOODING HAS ENDED.

LAT...LON 3671 11146 3670 11126 3690 11132 3690 11143

$$

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
950 AM MST THU AUG 16 2007

.SYNOPSIS...AFTERNOON AND EVENING THUNDERSTORMS WILL CONTINUE
THROUGH THE UPCOMING WEEKEND AS MONSOON MOISTURE REMAINS ACROSS THE
AREA. FOR SUNDAY AND EARLY NEXT WEEK...A DRIER SOUTHWEST FLOW WILL
LEAD TO A DECREASING CHANCE FOR THUNDERSTORMS ACROSS NORTHERN
ARIZONA.

&&

.DISCUSSION...HIGH PRESSURE REMAINS IN PLACE OVER THE SOUTHWEST WITH
THE RIDGE AXIS ORIENTED EAST TO WEST ACROSS AZ. THIS WILL MAINTAIN A
MOIST AND UNSTABLE AIRMASS ACROSS ARIZONA AND WILL RESULT IN ANOTHER
ROUND OF AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS.

OVERALL...THE AIRMASS TODAY OVER NORTHERN ARIZONA IS VERY SIMILAR TO
YESTERDAY...AS SEEN IN PRECIPITABLE WATER SATELLITE IMAGERY...THE
12Z SOUNDING...AND GPS BASED PRECIPITABLE WATER ESTIMATES OVER
BELLEMONT. A FEW SUBTLE NUANCES OF DIFFERENCES INCLUDING AN INCREASE
IN PRECIPITABLE WATER BY ABOUT 25 PERCENT NEAR THE UTAH
BORDER...WHICH HAS BEEN SPREAD NORTHWARD BY THE SOUTH-SOUTHEAST FLOW
OVER THE AREA. THEREFORE...MOISTURE AND INSTABILITY PROFILES SUPPORT
ANOTHER ROUND OF SCATTERED CONVECTION DEVELOPING LATE THIS
MORNING...POSSIBLY BECOMING MORE WIDESPREAD ACROSS THE FAR NORTH.
SOME STORMS WILL BE STRONG ENOUGH TO PRODUCE LARGE HAIL UP TO AN
INCH DIAMETER...ALTHOUGH STORMS OF THIS STRENGTH WILL LIKELY BE
EXTREMELY ISOLATED.

FOR FRIDAY...THE POSSIBILITY FOR ADDITIONAL MOISTURE PUSHING
NORTHWARD FROM THE GULF OF CA EXISTS AS THE CIRCULATION OFF THE
COAST OF BAJA CA AND THE COUNTERCLOCKWISE CIRCULATION DUE TO THE
SOUTHWEST HIGH COMBINE TO PRODUCE A MORE FAVORABLE SOUTHERLY FLOW
ALONG THE LOWER COLORADO VALLEY. THE QUESTION WILL BE HOW FAR NORTH
THE MOISTURE CAN TRANSPORT WITH A DRY TROUGH LINGERING OFF THE CA
COAST.

FOR SATURDAY AND INTO NEXT WEEK...MODELS HAVE BEEN SHOWING THE
DEVELOPMENT OF A DRIER SOUTHWESTERLY FLOW ACROSS ARIZONA. THIS
SHOULD RESULT IN A GENERAL DECREASE IN MOISTURE AND CONVECTIVE
ACTIVITY AS WELL AS WARMER DAYTIME TEMPERATURES. MODELS ARE FAIRLY
CONSISTENT WITH THIS GENERAL IDEA...BUT WITH THE RIDGE AXIS AND
MOISTURE LINGERING JUST OFF TO OUR SOUTH...IT WOULD ONLY TAKE SOME
SUBTLE DIFFERENCES TO KEEP THE MOISTURE BOUNDARY SOMEWHERE WITHIN
THE NORTHERN ARIZONA FORECAST AREA. GIVEN THE CLIMATOLOGICAL
CONDITIONS FOR THIS TIME OF YEAR...CURRENT FORECAST KEEPS AT LEAST
SLIGHT CHANCES OF THUNDERSTORMS THROUGH THE FORECAST PERIOD...AND
THIS LOOKS GOOD.

&&

.AVIATION...FOR THE 18Z PACKAGE...SCATTERED SHOWERS AND
THUNDERSTORMS ARE EXPECTED TO DEVELOP AFTER 18Z...FIRST OVER THE
MOUNTAIN AREAS...THEN DRIFTING WEST-NORTHWESTWARD TOWARD THE LOWER
ELEVATIONS. WINDS WILL BE ERRATIC AND GUSTY NEAR THUNDERSTORMS WITH
OCCASIONAL MVFR CONDITIONS...AND BRIEF IFR CONDITIONS NEAR THE
STRONGEST STORMS. SHOWERS AND THUNDERSTORMS WILL DECREASE IN
COVERAGE AFTER 03Z. AVIATION DISCUSSION NOT UPDATED FOR AMENDMENTS.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.

&&

ONTON/JJ

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
1000 AM MST THU AUG 16 2007

AZZ004>018-037>040-170700-
WESTERN MOGOLLON RIM-GRAND CANYON COUNTRY-YAVAPAI COUNTY MOUNTAINS-
YAVAPAI COUNTY VALLEYS AND BASINS-OAK CREEK AND SYCAMORE CANYONS-
MARBLE AND GLEN CANYONS-KAIBAB PLATEAU-COCONINO PLATEAU-
NORTHEAST PLATEAU AND MESAS HWY 264 NORTHWARD-
NORTHEAST PLATEAU AND MESAS SOUTH OF HWY 264-
CHINLE VALLEY-CHUSKA MOUNTAINS AND DEFIANCE PLATEAU-
BLACK MESA AREA-LITTLE COLORADO RIVER VALLEY IN COCONINO COUNTY-
LITTLE COLORADO RIVER VALLEY IN NAVAJO COUNTY-
LITTLE COLORADO RIVER VALLEY IN APACHE COUNTY-
EASTERN MOGOLLON RIM-WHITE MOUNTAINS-NORTHERN GILA COUNTY-
1000 AM MST THU AUG 16 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR APACHE...COCONINO...NORTHERN
GILA...NAVAJO...AND YAVAPAI COUNTIES IN NORTHERN ARIZONA.

.DAY ONE...TODAY

A MOIST UNSTABLE ATMOSPHERE WILL BE OVER NORTHERN ARIZONA ONCE AGAIN
TODAY. THUNDERSTORMS WILL LIKELY DEVELOP IN THE LATE MORNING OVER THE
HIGHER PEAKS FROM THE MOGOLLON RIM AND YAVAPAI COUNTY MOUNTAINS
NORTHWARD...SPREADING TO THE VALLEY AREAS LATER IN THE AFTERNOON.
THUNDERSTORM COVERAGE TODAY WILL BE SCATTERED TO NUMEROUS WITH SLIGHTLY
LOWER CHANCES FOR THUNDERSTORMS TAKING PLACE OVER THE FAR SOUTHWESTERN
YAVAPAI COUNTY VALLEYS. THE MAIN WEATHER THREAT TODAY WILL BE ISOLATED
STRONG THUNDERSTORMS PRODUCING LARGE HAIL UP TO AN INCH IN DIAMETER AND
VERY HEAVY RAIN. SOME LOCALIZED FLASH FLOODING IS POSSIBLE TODAY ACROSS
NORTHERN ARIZONA.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

A MOIST AND UNSTABLE AIR MASS WILL BRING DAILY SHOWERS AND
THUNDERSTORMS AND AN ISOLATED THREAT OF SEVERE WEATHER. THERE IS THE
POSSIBILITY OF A DRYING TREND BEGINNING ON SUNDAY AS DRIER
SOUTHWESTERLY FLOW PUSHES INTO THE GREAT BASIN. THERE IS STILL A
DEGREE OF UNCERTAINTY REGARDING HOW FAR SOUTH THE DRIER AIRSTREAM
WILL PUSH SO AFTERNOON AND EVENING THUNDERSTORMS CANNOT BE RULED
OUT AT THIS POINT...ESPECIALLY IN EAST CENTRAL ARIZONA.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.