Flash Flood Warning 7, NWS Flagstaff, AZ

NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
930 AM MST SAT AUG 04 2001

.SYNOPSIS...HIGH PRESSURE OVER THE CENTRAL PLAINS WILL BUILD
WESTWARD TOWARDS ARIZONA OVER THE NEXT FEW DAYS AND REMAIN IN PLACE
FOR MUCH OF THE UPCOMING WEEK. AS A RESULT...MONSOON MOISTURE WILL
REMAIN OVER THE STATE WITH A CHANCE OF SHOWERS AND THUNDERSTORMS
EACH DAY.

.DISCUSSION...MORNING KFGZ SOUNDING INDICATES SLIGHTLY DRIER AIR IN
THE LOWER LEVELS TODAY WITH PWAT VALUES BELOW CLIMATOLOGY. HIGH
PRESSURE IN LOWER LEVELS OVER NORTHERN GULF OF CA ALLOWING MORE
DRIER AIR TO INVADE WESTERN PORTIONS OF CWA UNDER SOUTHWEST FLOW.
HOWEVER...STRONG EASTERLY FLOW OVER NM IN THE UPPER LEVELS HAS
PUSHED DEEPEST MID AND UPPER LEVEL MOISTURE OVER CWA. THIS EASTERLY
FLOW WAS DEVOID OF DEEP CONVECTION OVER NM YESTERDAY WITH ALL
CONVECTION LOCATED ALONG LEADING EDGE WHICH IS NOW OVER CENTRAL AND
WESTERN AZ. A STRONG CIRCULATION CENTER WAS LOCATED NEAR THE TEXAS
BEND AREA AND IS MOVING TOWARD ARIZONA AS WELL. EXPECT THIS
CIRCULATION CENTER TO PRODUCE ORGANIZED COMPLEX SOMEWHERE OVER
SOUTHWEST NM AND NORTHWEST MEXICO AND PUSH SOUTH OF CWA THIS
EVENING. IF SUCH A COMPLEX DEVELOPS WOULD LIKELY THEN PUSH NORTHWARD
ONCE IT GETS NEAR PHX AND SPREAD OVER YAVAPAI COUNTY DURING THE LATE
EVENING AND OVERNIGHT HOURS.

IN THE SHORTER TERM...ADEQUATE MOISTURE AND HEATING IS IN PLACE FOR
THUNDERSTORM DEVELOPMENT OVER THE HIGHER TERRAIN MOVING NORTHWARD
INTO THE VALLEYS DURING THE AFTERNOON AND EVENING HOURS. IN THE
WEST...EXPECT DEWPOINTS TO DROP SOMEWHAT AS MIXING CONTINUES BUT
STILL SHOULD BE HIGH ENOUGH TO SUPPORT ISOLATED TO SCATTERED
COVERAGE...BUT PERHAPS MORE CHANCE OF GUSTY WINDS WITH THUNDERSTORMS
THERE. HEAVY RAINERS CENTRAL AND EASTERN PORTIONS. CURRENT FORECAST
HAS SITUATION COVERED FOR TODAY...BUT WILL LIKELY BUMP UP POPS IN
AFTERNOON PACKAGE ACROSS SOUTHERN ZONES FOR TONIGHT IF COMPLEX DOES
BEGIN TO DEVELOP.  STAUDENMAIER

.FGZ...NONE.

AZZ004>018-037>040-041930-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
830 AM MST SAT AUG 4 2001

...SCATTERED THUNDERSTORMS TODAY SOME PRODUCING HEAVY RAIN...

...SPOTTER CALLS OF RAINFALL AMOUNTS ARE ENCOURAGED...

DEEP MONSOONAL MOISTURE REMAINS OVER NORTHERN ARIZONA TODAY. MOSTLY
SUNNY SKIES THIS MORNING WILL RESULT IN RAPID HEATING AND QUICK
DEVELOPMENT OF THUNDERSTORMS OVER THE HIGHER TERRAIN. AS A
RESULT...SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP BEFORE NOON
OVER THE HIGHER TERRAIN AND SPREAD ACROSS MOST OF NORTHERN ARIZONA
BY EARLY EVENING. STORMS ARE EXPECTED TO BE MOST NUMEROUS OVER THE
WESTERN MOGOLLON RIM...WESTERN PORTIONS OF THE LITTLE COLORADO RIVER
VALLEY AS WELL AS YAVAPAI AND NORTHERN GILA COUNTIES. WITH THIS DEEP
MOISTURE IN PLACE...A FEW OF THESE STORMS MAY PRODUCE HEAVY RAINFALL
OF 1 TO 3 INCHES IN A SHORT PERIOD OF TIME. STORM MOVEMENT IS
EXPECTED TO BE TOWARD THE NORTH AT AROUND 5 TO 10 MPH.

STAUDENMAIER