Flash Flood Warning 1, NWS Salt Lake City, UT

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1050 AM MST FRI FEB 11 2005

...UPDATED TO INCLUDE 18Z AVIATION DISCUSSION...

.SYNOPSIS...A WARM MOIST UPPER LOW NEAR NORTHERN BAJA WILL MOVE
SLOWLY NORTHEASTWARD TODAY AND CROSS SOUTHERN UTAH ON SATURDAY.

&&

.DISCUSSION...UPPER LOW CENTERED OFF NRN BAJA LIFTING NEWD TODAY
AND HAS SPREAD CONSIDERABLE SUBTROPICAL MOISTURE INTO THE
SOUTHWESTERN STATES. PRECIP HAS BEGUN OVER THE SOUTHERN ZONES AND
WILL BECOME WIDESPREAD THROUGH THIS AFTERNOON THEN SPREAD INTO THE
NORTH EITHER LATE THIS AFTERNOON OR EARLY THIS EVE. EASTERLY
SURFACE GRADIENT IS TOO WEAK TO STIR OUT LOW LEVEL INVERSIONS AND
THERE IS A CHANCE THAT PRECIP COULD BEGIN AS FREEZING RAIN IN THE
SOUTHWEST VALLEYS FROM ABOUT CEDAR CITY NORTH AND THE EASTERN
BASINS FROM HANKSVILLE TO GREEN RIVER. UP NORTH...VALLEYS EXCEPT THE
CACHE SHOULD WARM ABOVE FREEZING BEFORE PRECIP STARTS AND THE CACHE
PROBABLY HAS DEEP ENOUGH COLD AIR FOR SNOW.

HEAVIER RAINFALL HAS STARTED OVER THE FAR SOUTHERN VALLEYS AND WE
HAVE ALREADY RECEIVED REPORTS OF HEAVY RUNOFF IN THE UPPER SANTA
CLARA RIVER DRAINAGE SO WILL GO WITH LONG DURATION FLASH FLOOD
WARNING THAT WILL INCLUDE MAIN RIVERS FOR THE AREAS CURRENTLY UNDER
THE WATCH.

SNOW LEVELS HAVE BEEN LOCALLY DOWN TO BELOW 6000 FEET BUT SHOULD
RISE TO ABOVE 8000 FEET BY LATER THIS AFTERNOON. CURRENT SNOW
ADVISORY IN GOOD SHAPE AND WILL LEAVE AS IS.

THE LOW OPENS UP AND QUICKLY MOVES EAST OF THE AREA LATE TOMORROW.
PRECIP WILL TAPER OFF OVER MOST VALLEY AREAS BY TOMORROW NIGHT. BY
THIS TIME HOWEVER...THE BAROCLINIC ZONE ASSOCIATED WITH THE NEXT
PACIFIC TROF MOVING THRU THE NRN ROCKIES WILL BE SAGGING INTO FAR
NRN UT AND COULD KEEP SNOW GOING ALONG THE ID BORDER. THIS FEATURE
REMAINS IN ABOUT THAT AREA THROUGH MON THEN SAGS A LITTLE FURTHER
MON NIGHT.

FOR NOW...HAVE UPDATED ZONES TO INCLUDE FREEZING RAIN THREAT AND TO
BUMP UP POPS A LITTLE FOR THE CENTRAL UT ZONES. WILL BE UPDATING
AGAIN SHORTLY TO ADDRESS HYDRO SITUATION.

&&

.AVIATION...TIMING OF WIDESPREAD PRECIPITATION INTO SLC VICINITY
AROUND 00Z LOOKS TO BE ON TRACK...BUT A CHANCE EXITS FOR A PERIOD OF
LIGHT RAIN AS EARLY AS 22Z.  SOME UNCERTAINTY EXISTS WITH REGARD TO
PRECIPITATION TYPE FOR SATURDAY MORNING.  COULD SEE A MIXTURE
OF SNOW OR POSSIBLE CHANGE OVER TO SNOW BETWEEN 12Z AND 18Z...BUT
GIVEN LOW CONFIDENCE...SNOW WORDING NOT INCLUDED IN VALID TAF.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...

UT...FLASH FLOOD WARNING TODAY EXTREME SOUTH. SEE SLCFFWSLC.
SNOW ADVISORY SRN MTNS ABOVE 8000 FEET THROUGH TODAY. SEE SLCWSWSLC.
WY...NONE.
ID...NONE.

&&

WILENSKY/BARJENBRUCH

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
610 AM MST FRI FEB 11 2005

UTZ007>010-016>021-121400-
CENTRAL AND SOUTHWEST MOUNTAINS-
GLEN CANYON RECREATION AREA/LAKE POWELL-HENRY MOUNTAINS-
SOUTH CENTRAL UTAH-SOUTHWEST UTAH-
UTAHS DIXIE AND ZION NATIONAL PARK-WASATCH MOUNTAINS I-80 NORTH-
WASATCH MOUNTAINS SOUTH OF I-80-WASATCH PLATEAU/BOOK CLIFFS-
WESTERN UINTA MOUNTAINS-
610 AM MST FRI FEB 11 2005

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE SOUTHERN THIRD AND ALL OF
THE MOUNTAINS OF UTAH.

.DAY ONE...TODAY

SUBSTANTIAL RAINFALL IS EXPECTED OVER VALLEY AREAS OF SOUTHERN UTAH
TODAY AND TONIGHT WHICH COULD RESULT IN SIGNIFICANT RISES IN SMALL
RIVERS AND STREAMS. SNOW WILL ACCUMULATE OVER THE SOUTHERN MOUNTAINS
ABOVE 8000 FEET TODAY THEN SPREAD INTO THE NORTHERN MOUNTAINS
TONIGHT. SEE THE LATEST HYDROLOGIC STATEMENT (SLCFFASLC) AND WINTER
WEATHER STATEMENT (SLCWSWSLC) FOR MORE INFORMATION.

.DAYS TWO THROUGH SEVEN... FRIDAY THROUGH WEDNESDAY

RAIN WILL CONTINUE OVER SOUTHERN UTAH ON SATURDAY BEFORE TAPERING
OFF SATURDAY NIGHT. SIGNIFICANT RISES ARE EXPECTED IN MAIN STEM
RIVERS AND LARGE STREAMS BY MIDDAY SATURDAY. SEE SLCFFASLC FOR THE
LATEST HYDROLOGIC STATEMENT. IN ADDITION TO THE RAIN...SNOW WILL
CONTINUE TO ACCUMULATE ON THE MOUNTAINS ABOVE 7000 FEET IN NORTHERN
UTAH AND ABOVE 8000 FT IN SOUTHERN UTAH THROUGH SATURDAY NIGHT.

SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER TO
NATIONAL WEATHER SERVICE.