Flash Flood Warning 25, NWS Flagstaff, AZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
230 AM MST TUE AUG 18 2008

.SYNOPSIS...DRIER AIR WILL FILTER INTO THE REGION FOR THE REMAINDER
OF THE WEEK. ISOLATED SHOWERS AND THUNDERSTORMS WILL CONTINUE FROM
FLAGSTAFF SOUTHEASTWARD...WITH CLEAR TO PARTLY CLOUDY SKIES ELSEWHERE.
NEAR NORMAL TEMPERATURES ARE EXPECTED TO CONTINUE.

&&

.DISCUSSION...HIGH PRESSURE IN THE MID TO UPPER LEVELS WAS CENTERED
ALONG THE CENTRAL BAJA CALIFORNIA COAST THIS MORNING. OVER THE NEXT
SEVERAL DAYS THIS HIGH PRESSURE SYSTEM WILL MOVE TO THE WEST. AT
THE SAME TIME...A SERIES OF SHORT-WAVE DISTURBANCES WILL BRUSH
NORTHERN ARIZONA. THE MAIN IMPACT OF THIS WEATHER SETTING WILL BE TO
BRING DRIER AND WARMER AIR FROM THE EASTERN PACIFIC ACROSS ARIZONA.
FOR TODAY...ENOUGH COOL AIR AND MOISTURE WILL REMAIN FOR ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS FROM ABOUT FLAGSTAFF EASTWARD.
HOWEVER...FOR WEDNESDAY INTO FRIDAY...FLOW FROM OVER THE EASTERN
PACIFIC WILL CONTINUE TO BRING A WARMER MID LEVEL CAPPING LAYER
ALONG WITH A DRIER AIR MASS. AS A RESULT...ONLY ISOLATED AFTERNOON
THUNDERSTORMS ARE ANTICIPATED...MAINLY ALONG THE EASTERN MOGOLLON
RIM AND WHITE MOUNTAINS. WEATHER CONDITIONS ACROSS THE REST OF
NORTHERN ARIZONA WILL BE CLEAR TO PARTLY CLOUDY.

FOR SATURDAY INTO EARLY NEXT WEEK...MODELS SHOW HIGH PRESSURE
WOBBLING ACROSS THE SOUTHWEST UNITED STATES IN RESPONSE TO PASSING
WEATHER DISTURBANCES TO THE NORTH. AT THIS TIME...IT LOOKS LIKE A
BIT OF AN INCREASE IN SHOWER AND THUNDERSTORM ACTIVITY BY SUNDAY AND
MONDAY AS HIGH PRESSURE MOVES OVER NEW MEXICO. HOWEVER...GIVEN THE
UNCERTAINTY OF THE POSITION OF THE HIGH PRESSURE CENTER BY EARLY
NEXT WEEK...HAVE OPTED FOR A LOW GRADE MONSOON FORECAST.

&&

.AVIATION......FOR THE 12Z PACKAGE...UNTIL 18Z...VFR CONDITIONS ARE
EXPECTED. AFT 18Z WIDELY SCATTERED STORMS ARE EXPECTED ACROSS THE
MOGOLLON RIM...WITH CLOUD BASES 130-150 MSL AND LCL MVFR CIGS IN THE
STRONGEST STORMS. AFT 02Z WEDS...VFR CONDITIONS ARE EXPECTED.
AVIATION DISCUSSION NOT UPDATED FOR AMENDMENTS.

&&

.FIRE WEATHER...SEE FIRE WEATHER FORECAST (FWFFGZ) FOR DISCUSSION OF
DAYS 1 AND 2.

THURSDAY THROUGH SATURDAY...EXPECT WIDELY SCATTERED AFTERNOON
SHOWERS AND THUNDERSTORMS ALONG THE MOGOLLON RIM AND WHITE
MOUNTAINS. LITTLE ACTIVITY IS EXPECTED ELSEWHERE. MINIMUM RH
VALUES ARE FORECAST TO BE ABOVE 15 PERCENT IN ALL LOCATIONS
EXCEPT ALONG THE UTAH/ARIZONA BORDER.

&&

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

PUBLIC...............MCCOLLUM
AVIATION/FIRE WX.....41

VISIT WEATHER.GOV/FLAGSTAFF FOR NORTHERN ARIZONA WEATHER INFORMATION.

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
955 PM MST SUN AUG 17 2008

AZZ004>018-037>040-180600-
KAIBAB PLATEAU-MARBLE AND GLEN CANYONS-GRAND CANYON COUNTRY-
COCONINO PLATEAU-YAVAPAI COUNTY MOUNTAINS-
NORTHEAST PLATEAUS AND MESAS HWY 264 NORTHWARD-CHINLE VALLEY-
CHUSKA MOUNTAINS AND DEFIANCE PLATEAU-
LITTLE COLORADO RIVER VALLEY IN COCONINO COUNTY-
LITTLE COLORADO RIVER VALLEY IN NAVAJO COUNTY-
LITTLE COLORADO RIVER VALLEY IN APACHE COUNTY-
WESTERN MOGOLLON RIM-EASTERN MOGOLLON RIM-WHITE MOUNTAINS-
NORTHERN GILA COUNTY-YAVAPAI COUNTY VALLEYS AND BASINS-
OAK CREEK AND SYCAMORE CANYONS-BLACK MESA AREA-
NORTHEAST PLATEAUS AND MESAS SOUTH OF HWY 264-
955 PM MST SUN AUG 17 2008

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EAST CENTRAL
ARIZONA...NORTH CENTRAL ARIZONA...NORTHEAST ARIZONA AND WEST
CENTRAL ARIZONA.

.DAY ONE...TONIGHT

ONLY ISOLATED SHOWERS OR THUNDERSTORMS ARE EXPECTED FOR THE REST
OF TONIGHT...PRODUCING LIGHT AMOUNTS OF RAIN.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

FOR MONDAY AND BEYOND...A SLOW DRYING TREND IS POSSIBLE AS HIGH
PRESSURE BUILDS IN FROM THE WEST...WITH A SLIGHT CHANCE FOR
SHOWERS AND THUNDERSTORMS THROUGH THE FORECAST PERIOD.

.SPOTTER INFORMATION STATEMENT...

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