Red Flag Warning 1, NWS Salt Lake City, UT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
905 PM MDT SUN APR 6 2008

.SYNOPSIS...A WEAK WEATHER DISTURBANCE WILL MOVE EAST ACROSS
NORTHERN UTAH THIS EVENING. THE NEXT COLD PACIFIC STORM SYSTEM WILL
FOLLOW QUICKLY FOR MONDAY. ANOTHER PACIFIC WEATHER SYSTEM WILL
MOVE INTO THE GREAT BASIN MIDWEEK.

&&

.DISCUSSION...THE COLD CORE UPPER TROUGH JUST NOW MOVING INTO THE
PACIFIC NW STILL ON TRACK TO REACH THE NRN GREAT BASIN/NRN ROCKIES
FOR LATER TONIGHT THROUGH MONDAY. WEAK CONVECTION DID BREAK OUT
AHEAD OF THE TROUGH ACROSS NRN/ERN NV THROUGH NRN/CNTRL UTAH THIS
AFTERNOON/EVENING. MUCH OF THE CONVECTION APPEARS TO HAVE FORMED
ALONG THE OLD NEAR 700MB BAROCLINIC ZONE ACROSS CNTRL UTAH. A SECOND
AREA OF LOOSELY ORGANIZED SHOWER/ISOLATED THUNDERSTORMS HAVE
DEVELOPED ALONG A WEAK SHORTWAVE ACROSS NE NV/EXTREME NW UT. THIS
SHORTWAVE WILL MOVE QUICKLY EAST ACROSS FAR NRN UTAH THIS EVENING...
WITH A POSSIBLE BRIEF BREAK BEFORE PRECIP RETURNS WITH THE MAINLY
TROUGH.

THE FOCUS OF THE HEAVIEST PRECIP WITH THE MAIN TROUGH WILL BE ACROSS
THE NRN HALF OF THE FORECAST AREA MONDAY. LOW-LEVEL COLD ADVECTION
WILL START ACROSS NW UT AFTER MIDNIGHT. THE MID-LEVEL COLD AIR WILL
FOLLOW ON MONDAY...WITH RAPIDLY INCREASING INSTABILITY ACROSS THE
NRN THIRD OF UTAH AS THE COLDEST AIR ARRIVES MID-MORNING. SOLID
DYNAMIC LIFT WORKING ON THIS UNSTABLE AIR SHOULD LEAD TO WIDESPREAD
AND POTENTIAL HEAVY PRECIP MONDAY. OROGRAPHIC INFLUENCES WILL COME
INTO PLAY IN THIS PATTERN...SO THE HEAVY SNOW WARNING LOOKS GOOD
FOR PORTIONS OF THE NRN MOUNTAINS. SNOW LEVELS COULD BE A TOUGH CALL
ALONG THE URBAN CORRIDOR. SUSPECT THAT THE EARLY RAIN/SNOW MIX WILL
GO TO SNOW OVER ALL BUT THE LOWEST ELEVATIONS BY LATE MORNING.
ACCUMULATING SNOWS STILL LOOK TO BE ON THE LOW SIDE...OUTSIDE OF
POSSIBLY THE HIGHER BENCH AREAS.

SHOWERY PRECIP COULD LINGER WELL INTO MONDAY EVENING AS THE
MID-LEVEL AIRMASS IS SLOW TO WARM. WILL KEEP SHOWERY PRECIP GOING
OVER THE FAR NRN ZONES...THOUGH ACCUMULATING SNOWS SHOULD FOR THE
MOST PART BE OVER BY MID-EVENING.

A SHORTWAVE RIDGE ACROSS THE AREA TUESDAY WILL BE FOLLOWED BY THE
NEXT PACIFIC TROUGH WEDNESDAY. THE GFS MODEL THE PAST SEVERAL DAYS
HAS BEEN ALL OVER THE LOT AS TO WHERE TO TRACK THIS SYSTEM. THE
ECMWF IN CONTRAST HAS BEEN FAR MORE CONSISTENT IN THAT IT SPLITS
THIS TROUGH HARD AND TAKES THE BULK OF THE ENERGY WELL SOUTH INTO AZ.
THE COOL/GENERALLY UNSTABLE AIRMASS THAT WILL SETTLE OVER UTAH
MIDWEEK WILL PROBABLY PRODUCE PLENTY OF CONVECTIVE SHOWERY...WITH
LITTLE ORGANIZED PRECIP AS THE BEST DYNAMIC LIFT REMAINS TOO FAR
REMOVED TO THE SOUTH.

&&

.AVIATION...VFR CONDITIONS WILL PREVAIL AT THE SLC TERMINAL THROUGH
AT LEAST 12Z MON WITH CEILINGS GENERALLY ABOVE 7000 FT AGL. LIGHT
NORTHWEST WINDS SHOULD SWITCH TO SOUTHEASTERLY BY 04Z. A COLD FRONT
WILL CROSS THE AIRFIELD 13-14Z MONDAY WITH RAIN AND SNOW LIKELY
ALONG AND BEHIND THE FRONT AND WINDS SHIFTING BACK TO NORTHWEST.
MVFR CIGS AND VSBYS ARE LIKELY IN THE PRECIPITATION AND IFR OR EVEN
LIFR CONDITIONS ARE POSSIBLE IN SNOW AFTER 14Z THRU 18Z.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...HEAVY SNOW WARNING FROM 4 AM MONDAY TO 8 PM MONDAY FOR UTZ007-
     UTZ008.

     SNOW ADVISORY FROM 9 PM SUNDAY TO 8 PM MONDAY FOR UTZ010-UTZ517.

     SNOW ADVISORY FROM 4 AM MONDAY TO 8 PM MONDAY FOR UTZ006-UTZ009.

WY...NONE.

&&

CONGER/WILENSKY

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
607 AM MDT SUN APR 6 2008

UTZ001>016-019>021-517-518-WYZ021-071100-
CACHE VALLEY/UTAH PORTION-NORTHERN WASATCH FRONT-
SALT LAKE AND TOOELE VALLEYS-SOUTHERN WASATCH FRONT-
GREAT SALT LAKE DESERT AND MOUNTAINS-WASATCH MOUNTAIN VALLEYS-
WASATCH MOUNTAINS I-80 NORTH-WASATCH MOUNTAINS SOUTH OF I-80-
WESTERN UINTA MOUNTAINS-WASATCH PLATEAU/BOOK CLIFFS-
WESTERN UINTA BASIN-CASTLE COUNTRY-SAN RAFAEL SWELL-
SANPETE/SEVIER VALLEYS-WEST CENTRAL UTAH-SOUTHWEST UTAH-
UTAHS DIXIE AND ZION NATIONAL PARK-SOUTH CENTRAL UTAH-
GLEN CANYON RECREATION AREA/LAKE POWELL-CENTRAL MOUNTAINS-
SOUTHERN MOUNTAINS-SOUTHWEST WYOMING-
607 AM MDT SUN APR 6 2008

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE WESTERN TWO THIRDS OF
UTAH AND SOUTHWEST WYOMING.

.DAY ONE...TODAY AND TONIGHT

A MOIST WESTERLY FLOW ALOFT WILL BE OVER NORTHERN UTAH AND
SOUTHWEST WYOMING THROUGH TONIGHT. LIGHT SHOWERS OF RAIN AND SNOW
WILL RESULT. SOUTHERN UTAH WILL BE DRY AND PARTLY CLOUDY.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

A PACIFIC STORM WILL CROSS THE OUTLOOK AREA MONDAY WITH ANOTHER
STORM FOR WEDNESDAY. WARMER HIGH PRESSURE IS EXPECTED TO BUILD
OVER THE REGION FOR NEXT WEEKEND.

.SPOTTER INFORMATION STATEMENT...

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

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)