Flash Flood Warning 15, NWS Flagstaff, AZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF
945 PM MST FRI FEB 18 2005

.SYNOPSIS...A LOW PRESSURE SYSTEM OFF THE COAST OF CALIFORNIA WILL
BRING PERIODS OF RAIN AND SNOW TO THE AREA THROUGH THE WEEKEND AND
INTO NEXT WEEK. SNOW LEVELS WILL LOWER TO NEAR 6000 FEET BY SATURDAY
WITH ACCUMULATING SNOW EXPECTED OVER THE HIGHER TERRAIN TONIGHT AND
TOMORROW.

&&

.DISCUSSION...NORTHERN AND CENTRAL ARIZONA IN SOMEWHAT OF A LULL AT
THE CURRENT TIME...BUT THIS WILL CHANGE. A STRONG S/WV MOVING UP THE
GULF OF CALIFORNIA WILL BRING A ROUND OF MODERATE TO HEAVY PRECIP TO
THE AREA BY MIDNIGHT...LASTING FOR ABOUT 4 HOURS. A SECOND S/WV
ROUNDING THE SOUTHERN END OF THE OFFSHORE LOW WILL ARRIVE AROUND
SUNRISE SATURDAY...WITH MORE MODERATE TO HEAVY PRECIPITATION LASTING
THROUGH EARLY SATURDAY AFTERNOON. THE GFS HAS BEEN HITTING THESE
PLUMES HARD...WITH SOME POSSIBILITY OF CONVECTIVE FEEDBACK. THE ETA
HAS NOT BEEN HITTING THESE PLUMES HARD ENOUGH...AND PROBABLY DID NOT
INITIALIZE WELL. THE FLASH FLOOD WATCH WILL REMAIN IN EFFECT AND IS
ENCOMPASSING THE PROBLEM AREAS WELL. THE SNOW ADVISORIES TONIGHT
LOOK A BIT MORE IFFY...AS SNOW LEVELS ARE STILL ABOVE 7000 FEET. THE
SECOND WAVE SATURDAY MORNING WILL BRING LEVELS DOWN TO AROUND 6500
FEET...SO WE WILL LEAVE THE WSW OUT FOR NOW. MOIST AND UNSTABLE AIR
WILL CONTINUE TO STREAM THROUGH CENTRAL ARIZONA THROUGH SUNDAY WITH
NEARLY CONTINUOUS SHOWERS OF RAIN AND SNOW. ANOTHER STRONG LOW WILL
APPROACH MONDAY NIGHT THROUGH WEDNESDAY. THIS SYSTEM WILL LIKELY
BRING MORE PROBLEMS FOR MUCH OF THE AREA. WE WILL MAKE UPDATES FOR
LATEST TIMING TRENDS...BUT OVERALL...THE ZONES AND HEADLINE PRODUCTS
ARE IN GOOD SHAPE. PETERSON.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...FFA UNTIL SATURDAY EVENING FOR
ARIZONA ZONES 006/007/008/018/037/038.

SNOW ADVISORY FROM 10 PM MST TONIGHT UNTIL 12 PM MST SATURDAY FOR
ARIZONA ZONES 004/006/007/015/016.

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
700 AM MST FRI FEB 18 2005

AZZ004>018-037>040-191400-
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 FRI FEB 18 2005

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

.DAY ONE...TODAY

A LOW PRESSURE SYSTEM NEAR THE SOUTHWEST UNITED STATES WILL BRING
SIGNIFICANT PRECIPITATION TO NORTHERN ARIZONA TODAY. RAINFALL
AMOUNTS OF ONE TO TWO INCHES CAN BE EXPECTED WITH LOCALLY HIGHER
AMOUNTS POSSIBLE. THIS RAINFALL COULD RESULT IN FLOODING ACROSS
PORTIONS OF ARIZONA TODAY. A FLASH FLOOD WATCH HAS BEEN ISSUED. SEE
PHXFFAFGZ FOR DETAILS.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

LOW PRESSURE WILL CONTINUE TO BRING SIGNIFICANT PRECIPITATION TO
NORTHERN ARIZONA ON SATURDAY AND A FLASH FLOOD WATCH WILL REMAIN IN
EFFECT THROUGH SATURDAY EVENING.

SNOW LEVELS WILL FALL TO AROUND 6500 FEET EARLY SATURDAY MORNING.
MODERATE SNOWFALL ACCUMULATIONS ARE LIKELY AT THE HIGHER ELEVATIONS
AND A SNOW ADVISORY MAY BE NECESSARY.

.SPOTTER INFORMATION STATEMENT...

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