Severe Thunderstorm Warning 77, NWS Flagstaff, AZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
945 AM MST TUE AUG 23 2005

.SYNOPSIS...INCREASED MOISTURE WILL BRING SHOWERS AND THUNDERSTORMS
TO MOST OF THE AREA TODAY AND INTO THIS EVENING. MOISTURE WILL
DECREASE AFTER TODAY...WITH A DECREASING CHANCE FOR SHOWERS AND
THUNDERSTORMS FOR THE REMAINDER OF THE WEEK. EXPECT COOLER HIGH
TEMPERATURES TODAY COMPARED WITH THE LAST SEVERAL DAYS...AND
GRADUALLY INCREASING DAYTIME TEMPERATURES THROUGH THE WEEKEND.

&&

.DISCUSSION...A SIGNIFICANT SURGE OF MOISTURE HAS ENTERED THE AREA
OVERNIGHT. KFGZ SOUNDING SHOWING 0.76 INCHES PW AND NEAR 800 J/KG
CAPE AND THESE VALUES ARE LIKELY INCREASED BASED ON ADVECTION FROM
KPSR SOUNDING TO THE SOUTH. OTHER FEATURES OF NOTE ARE A TROUGH AXIS
ALONG THE AZ/CA BORDER WITH A SHORTWAVE IMPULSE FORECAST BY GFS AND
NAM TO EJECT NORTHEASTWARD DURING THE DAY TO PROVIDE DYNAMIC LIFT
AND A POSSIBLE FOCUS FOR CONVECTION. 12Z GFS ADVERTISING 20-30 KT
500 MB SOUTHWEST FLOW ACROSS THE CWA WHICH SHOULD PROVIDE FOR
ADEQUATE SHEAR FOR ORGANIZED CONVECTION. BEST MOISTURE WILL BE OVER
MOGOLLON RIM AND SOUTHWARD...HOWEVER SEEMS LIKELY THAT BEST SHEAR
MAY DEVELOP IN NORTHERN PORTIONS OF THE STATE DUE TO SHORTWAVE
FEATURE. STORM MOTION WILL GENERALLY BE NORTHEASTWARD. BEST THREAT
FOR HEAVY PRECIP WILL LIKELY BE NEAR THE MOGOLLON RIM AND WHITE
MOUNTAINS...WHILE MORE ISOLATED CONVECTION IS EXPECTED NEAR THE UT
BORDER ALTHOUGH SOME OF THE STRONGEST STORMS MAY BE IN THIS AREA.
POPS HAVE BEEN RAISED TO LIKELY CATEGORY ACROSS MOST OF THE CWA AND
THIS LOOKS GOOD...SO NO SHORT TERM UPDATES PLANNED. FOR
TOMORROW...WILL CONSIDER INCREASING POPS AS MOISTURE LIKELY TO
LINGER ACROSS THE AREA FROM TODAY.

&&

.AVIATION...FOR THE 18Z PACKAGE...EXPECT SCT TSRA/SHRA BY LATE
MORNING AS A WEAK UPPER LEVEL DISTURBANCE MOVES ACROSS THE AREA. THE
CONVECTION IS EXPECTED TO DIMINISH THIS EVENING. AVIATION DISCUSSION
NOT UPDATED FOR AMENDMENTS.

&&

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

&&

DJO/DF

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
1000 AM MST TUE AUG 23 2005

AZZ004>018-037>040-240700-
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 TUE AUG 23 2005

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

.DAY ONE...TODAY

NUMEROUS THUNDERSTORMS AREA EXPECTED TO DEVELOP BY MIDDAY NEAR THE
MOGOLLON RIM AND WHITE MOUNTAINS...WHILE MORE ISOLATED CONVECTION
IS EXPECTED NEAR THE UTAH BORDER ALTHOUGH SOME OF THE STRONGEST
STORMS MAY BE IN THIS AREA. HEAVY PRECIPITATION IS THE GREATEST
THREAT TODAY OVER AND NORTHEAST OF THE MOGOLLON RIM AND WHITE
MOUNTAINS...WHILE HAIL UP TO 1 INCH DIAMETER IS POSSIBLE FROM
ISOLATED STORMS ACROSS THE REGION.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

DRY WESTERLY FLOW WILL BRING A DECREASING CHANCE OF THUNDERSTORMS
ACROSS THE AREA THROUGH THE LATTER HALF OF THE WEEK...WITH NEARLY
DRY CONDITIONS EXPECTED BY THURSDAY THROUGH MONDAY.

.SPOTTER INFORMATION STATEMENT...

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