Hail in Arizona, September 15, 2011

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
926 AM MST THU SEP 15 2011

.SYNOPSIS...A LOW PRESSURE SYSTEM OVER NORTHERN ARIZONA WILL
BRING A CHANCE OF SHOWERS AND THUNDERSTORMS TO THE AREA UNTIL LATE
THURSDAY AND FRIDAY. COOLER THAN NORMAL TEMPERATURES WILL ALSO
CONTINUE. EXPECT A DRYING TREND BY FRIDAY...WITH HIGH TEMPERATURES
WARMING BACK TO AROUND SEASONAL AVERAGES BY MONDAY.

&&

.DISCUSSION...THE UPPER LEVEL TROUGH CURRENTLY SITUATED OVER THE
AZ/UT BORDER IS HELPING TO SUSTAIN SOME LIGHT TO MODERATE SHOWERS
MOSTLY NORTH AND EAST OF THE RIM THIS MORNING WITH A FEW ISOLATED
SHOWERS ELSEWHERE. INCREASED CLOUD COVER FROM FLAGSTAFF NORTHWARD
MAY LIMIT MAX TEMPERATURES A BIT TODAY AND HAVE MADE MINOR TWEAKS TO
TODAY'S HIGHS. OTHERWISE PREVIOUS FORECAST IS IN GOOD SHAPE WITH
NORTH CENTRAL AND NORTHEAST AZ BEING FAVORED FOR CONVECTIVE ACTIVITY
THIS AFTERNOON AND EVENING.

&&

.PREVIOUS DISCUSSION (247 AM)...TODAY...THE TROUGH WILL SLOWLY LIFT
NORTHEAST INTO SOUTHERN UTAH WITH THE BEST SYNOPTIC LIFT...AND
INSTABILITY OVER NORTH CENTRAL AND NORTHEAST ARIZONA. EXPECT
SCATTERED SHOWERS AND THUNDERSTORMS WITH THE BEST COVERAGE AND
CHANCE FOR STRONGER STORMS TO BE NORTH AND EAST OF THE MOGOLLON RIM.
DRYING WILL WORK IN FROM THE SOUTHWEST THIS EVENING REDUCING
PRECIPITATION CHANCES.

FRIDAY...ANOTHER TROUGH APPROACHES FROM THE WEST...PROVIDING WEAK
LIFT AND INSTABILITY TO KEEP A CHANCE OF SHOWERS AND THUNDERSTORMS
GOING MAINLY NORTH OF I-40 AND ISOLATED ACTIVITY TO THE SOUTH.
COOLER THAN NORMAL TEMPERATURES WILL CONTINUE.

SATURDAY...STILL ENOUGH MOISTURE AND INSTABILITY LEFT FROM THE
DEPARTING TROUGH TO KEEP AN ISOLATED THREAT OF AFTERNOON SHOWERS AND
THUNDERSTORM ALONG THE ARIZONA UTAH BORDER. COOLER THAN NORMAL
TEMPERATURES CONTINUING.

SUNDAY THROUGH TUESDAY...A BUILDING HIGH PRESSURE RIDGE IN THE
SOUTHWEST WILL BRING DRY CONDITIONS AND HIGH TEMPERATURES THAT WILL
WARM BACK TO SEASONAL VALUES.

WEDNESDAY AND THURSDAY...A COLD FRONT WILL SLIDE SOUTH AND WEST
THROUGH NEW MEXICO...THIS FEATURE WILL ACT TO PUSH SOME MOISTURE AND
INSTABILITY NORTHWEST INTO THE WHITE MOUNTAIN AREA ON WEDNESDAY.
THEN BY THURSDAY...A SOUTHEASTERLY FLOW IS FORECAST TO DEVELOP AND
PUSH SOME SUBTROPICAL MOISTURE NORTHWEST POSSIBLY INTO GILA
COUNTY... THE EASTERN MOGOLLON RIM...AND INTO A PORTIONS OF THE
YAVAPAI COUNTY MOUNTAINS.

&&

.AVIATION...FOR THE 18Z PACKAGE...LOW PRESSURE WILL SLOWLY HEAD
EASTWARD ACROSS NORTHERN ARIZONA TODAY. AS A RESULT...MOISTURE WILL
COMBINE WITH COOL TEMPERATURES ALOFT FOR SCATTERED THUNDERSTORM
COVERAGE. MVFR/IFR CONDITIONS WILL ACCOMPANY STORMS...WITH HAIL UP
TO ONE INCH IN DIAMETER POSSIBLE WITH STRONGER STORMS. STORM
ACTIVITY WILL DIMINISH TO ISOLATED COVERAGE AFTER 02Z. AVIATION
DISCUSSION NOT UPDATED FOR AMENDMENTS.

&&

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

&&

PUBLIC..................MCS/TC
AVIATION................DJO

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

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
745 AM MST THU SEP 15 2011

AZZ004>018-037>040-160815-
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-
745 AM MST THU SEP 15 2011

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

.DAY ONE...TODAY AND TONIGHT

THE LOW PRESSURE TROUGH WILL SLOWLY LIFT NORTHEAST INTO SOUTHERN
UTAH WITH THE BEST LIFT...AND INSTABILITY OVER NORTH CENTRAL AND
NORTHEAST ARIZONA. EXPECT SCATTERED SHOWERS AND THUNDERSTORMS WITH
THE BEST COVERAGE AND CHANCE FOR STRONGER STORMS TO BE NORTH AND
EAST OF THE MOGOLLON RIM. A FEW STORMS MAY BE CAPABLE OF HAIL UP TO
AN INCH. DRIER AIR WILL WORK IN FROM THE SOUTHWEST THIS EVENING
REDUCING PRECIPITATION CHANCES.

LOCALIZED HEAVY RAIN PRODUCING STORMS...AS WELL AS STORMS CROSSING
THE SAME AREA REPEATEDLY...WILL ALSO BRING THE THREAT FLASH
FLOODING. THIS THREAT WILL BE MAXIMIZED OVER OUR BURN AREAS...SUCH
AS THE SCHULTZ...LOCUST...AND WALLOW FIRE BURN SCARS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

FRIDAY...ANOTHER TROUGH APPROACHES FROM THE WEST...PROVIDING WEAK
LIFT AND INSTABILITY TO KEEP A CHANCE OF SHOWERS AND THUNDERSTORMS
GOING MAINLY NORTH OF I-40 AND ISOLATED ACTIVITY TO THE SOUTH.

SATURDAY...STILL ENOUGH MOISTURE AND INSTABILITY LEFT FROM THE
DEPARTING TROUGH TO KEEP AN ISOLATED THREAT OF AFTERNOON SHOWERS AND
THUNDERSTORM ALONG THE ARIZONA UTAH BORDER.

SUNDAY THROUGH TUESDAY...A BUILDING HIGH PRESSURE RIDGE IN THE
SOUTHWEST WILL BRING DRY CONDITIONS.

.SPOTTER INFORMATION STATEMENT...

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