Severe Thunderstorm Warning 138, NWS Flagstaff, AZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
230 PM MST SUN JUL 09 2006

.SYNOPSIS...A MOIST AND UNSTABLE AIRMASS WILL REMAIN OVER NORTHERN
ARIZONA THIS WEEK WITH A CHANCE FOR SHOWERS AND THUNDERSTORMS EACH
DAY.

&&

.DISCUSSION...THE MID TO UPPER RIDGE SHIFTED SOUTHWARD TO OVER
NORTHERN MEXICO AND CENTRAL TEXAS OVER THE PAST 24 HOURS. DRY
WESTERLY FLOW ALOFT AND SUNNY SKIES THIS MORNING COMBINED WITH A
MOIST AIR MASS BELOW 500 MB FOR ANOTHER ROUND OF ISOLATED TO
SCATTERED THUNDERSTORMS. A FEW STORMS HAVE BEEN SEVERE WITH AN
OBSERVER IN EAST FLAGSTAFF REPORTING NICKEL SIZE HAIL. TEMPERATURES
ALOFT COOL HEADING INTO THIS EVENING AS A WEAK DISTURBANCE MOVES
ACROSS NORTHERN ARIZONA FROM THE WEST. WILL HAVE TO REMAIN ON THE
LOOKOUT FOR SOME OVERNIGHT THUNDERSTORM ACTIVITY AS REMNANT OUTFLOW
BOUNDARIES AND MOIST BOUNDARY LAYER INTERACT WITH THE COOLING ALOFT.
IN ANY EVENT...ISOLATED SEVERE THUNDERSTORMS ARE EXPECTED TO
CONTINUE UNTIL AROUND SUNSET. WE WILL JUST HAVE TO WAIT AND SEE IF
ANY NIGHTTIME ACTIVITY TRANSPIRES.

FOR MONDAY AND TUESDAY THE MID TO UPPER RIDGE WILL REMAIN OVER
NORTHERN MEXICO AND CENTRAL TEXAS. THIS WILL RESULT DRY CONDITIONS
ABOVE 500 MB BUT MOIST CONDITIONS BELOW. MODELS CONTINUE TO SHOW
SOME DRYING IN THE BOUNDARY LAYER BUT THIS IS A COMMON WEAKNESS OF
THE MODELS. THINK THERE WILL BE ENOUGH MOISTURE FLOW FROM MEXICO TO
KEEP THE BOUNDARY LAYER MOIST. THE SOUTHWEST TO WEST FLOW WILL BRING
IN A SLIGHT WARM CAP WHICH WILL REDUCE THE CHANCES OF MEASURABLE
PRECIPITATION. HOWEVER...WESTERLY FLOW NORMALLY RESULTS IN BETTER
VERTICAL SHEAR PROFILES FOR ORGANIZED CONVECTION AND THE MID LEVEL
WARM CAP CAN HELP THE AIR MASS ACHIEVE HIGHER CAPE VALUES. SO FOR
MONDAY AND TUESDAY EXPECT FEWER STORMS BUT THE STORMS THAT DO FORM ARE
LIKELY TO BE STRONGER WITH A HIGHER POTENTIAL TO PRODUCE SEVERE
WEATHER AND FLOODING.

FROM WEDNESDAY INTO SATURDAY MODELS CONTINUE TO SHOW THE MID TO
UPPER RIDGE SHIFTING NORTHWARD. THIS WOULD BE ACCOMPANIED BY A PUSH
OF DEEP MONSOON MOISTURE NORTHWARD AND A RETURN TO WIDESPREAD
THUNDERSTORM ACTIVITY.

&&

.AVIATION...FOR THE 00Z PACKAGE...SHOWERS AND THUNDERSTORMS WILL
CONTINUE FOR THE REST OF THE AFTERNOON...DIMINISHING THROUGH 03Z
TONIGHT. SKIES WILL SLOWLY BECOME PARTLY CLOUDY THROUGH THE NIGHT
TIME HOURS. EXPECT SHOWERS AND THUNDERSTORMS TO REDEVELOP AFTER 18Z
MONDAY ACROSS THE HIGH TERRAIN AREAS. AVIATION DISCUSSION NOT
UPDATED FOR AMENDMENTS.

&&

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

&&

PHXWRKHWO DDHHMM

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
1000 AM MST SUN JUL 9 2006

AZZ004>018-037>040-100700-
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 SUN JUL 9 2006

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

.DAY ONE...TODAY

A MOIST AND UNSTABLE AIR MASS WILL REMAIN OVER NORTHERN ARIZONA
TODAY. EXPECT ANOTHER ROUND OF SCATTERED THUNDERSTORMS THIS AFTERNOON
AND EVENING. THE VERTICAL WIND PROFILE WILL SUPPORT AN ISOLATED
SEVERE THUNDERSTORM OR TWO WITH HAIL UP TO AN INCH IN DIAMETER
THE MAIN THREAT. FOR THE MOST PART THUNDERSTORMS WILL BE LOCATED FROM
FLAGSTAFF...HEBER AND SHOW LOW NORTHWARD.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

THE CHANCE FOR THUNDERSTORMS WILL CONTINUE ACROSS NORTHERN ARIZONA
EACH DAY. GUSTY WINDS...LOCALLY HEAVY RAIN AND HAIL WILL BE POSSIBLE
WITH THE STRONGER STORMS.

.SPOTTER INFORMATION STATEMENT...

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