Flash Flood Warning 18, NWS Flagstaff, AZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF
245 PM MST SAT FEB 19 2005

.SYNOPSIS...A LOW PRESSURE SYSTEM OFF THE COAST OF CALIFORNIA WILL
KEEP THE ATMOSPHERE UNSTABLE OVER THE STATE THROUGH THE WEEKEND.
LIGHT SHOWERS WILL CONTINUE TONIGHT AND DECREASE ON SUNDAY. ANOTHER
STORM SYSTEM WILL APPROACH THE STATE LATE MONDAY. THIS WILL BRING
LOWER ELEVATION RAIN AND ACCUMULATING SNOW TO THE HIGHER TERRAIN
THROUGH MID WEEK.

&&

.DISCUSSION...CWA WILL REMAIN UNDER CYCLONIC FLOW OVERNIGHT. WEAK
S/WV SEEN ON WV IMAGERY MOVING TOWARD S CA WILL ROTATE ACROSS THE
DESERT SW TONIGHT. SOME LIFT ASSOCIATED WITH THIS FEATURE PER DIV-Q
PROG ALONG WITH UPPER LEVEL DIVERGENCE. QPF AMOUNTS LOW WITH ONLY AN
INCH OR TWO OF NEW SNOW ACCUMULATION EXPECTED OVER THE HIGHER TERRAIN
AREAS. NOTED SOME CONVECTION THIS AFTERNOON JUST WEST OF THE CWA
WHERE AIR MASS IS THE MOST UNSTABLE...LIS OF ZERO TO -2. EVENING
THUNDER POSSIBLE IN EXTREME WESTERN ZONES.

AIR MASS STABILIZES TOMORROW AS WEAK UPPER RIDGE BUILDS OVER THE
STATE IN RESPONSE TO DEEPENING LOW OFF THE WEST COAST. WHILE UPPER
LEVELS DRY LINGERING LOWER LEVEL MOISTURE AND WEAK LIFT MAKE SCT
SHOWERS POSSIBLE. THE NEXT TROF APPROACHES THE STATE LATE MONDAY INTO
TUESDAY. EXPECT AN UPSWING IN PRECIP AS DEEP LAYERED MOISTURE INVADES
THE STATE. THIS SYSTEM IS COLDER THAN THE LAST. H7 TEMPS AS LOW AS -7
DEGREES C PROGGED WITH SNOW LEVELS DROPPING TO NEAR 5500 FT.
SIGNIFICANT SNOW ACCUMULATION AGAIN POSSIBLE OVER THE HIGHER TERRAIN.
PRECIP CHANCES DROP OFF ON THURSDAY AS TROF WEAKENS. MEDIUM RANGE
MODELS DIFFERENT FROM YESTERDAYS RUN IN KEEPING BAGGY TROF OVER
THE REGION INTO THE WEEKEND...THEREFORE WILL INDICATE A SLIGHT CHANCE
OF PRECIP THRU SAT.

STREAM LEVELS GENERALLY DROPPING AND SEE NO HYDRO ISSUES FOR THE REST
OF THE WEEKEND. HAVE CANCELED THE FLASH FLOOD WATCH. DF

&&

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

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
700 AM MST SAT FEB 19 2005

AZZ004>018-037>040-201400-
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-
700 AM MST SAT FEB 19 2005

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

.DAY ONE...TODAY

LOW PRESSURE WILL CONTINUE TO BRING SIGNIFICANT PRECIPITATION TO
NORTHERN ARIZONA TODAY AND A FLASH FLOOD WATCH WILL REMAIN IN
EFFECT FOR PORTIONS OF THE AREA THROUGH THIS EVENING.
SEE PHXFFAFGZ FOR DETAILS.

SNOW LEVELS WILL FALL TO AROUND 6000 FEET BY MIDDAY. MODERATE
SNOWFALL ACCUMULATIONS ARE LIKELY AT THE HIGHER ELEVATIONS
AND A SNOW ADVISORY IS IN EFFECT UNTIL NOON.
SEE PHXWSWFGZ FOR DETAILS.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

LOOKS LIKE THE NEXT THREAT FOR SIGNIFICANT HIGHER ELEVATION SNOW AND LOW
ELEVATION RAIN WILL COME MONDAY NIGHT AND TUESDAY WITH A ANOTHER
STRONG PACIFIC STORM SYSTEM.

.SPOTTER INFORMATION STATEMENT...

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