FXUS65 KSLC 071717
AFDSLC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1017 AM MST MON DEC 7 2009

.SYNOPSIS..A STORM SYSTEM WILL SLIDE EAST OUT OF CALIFORNIA AND 
ACROSS THE GREAT BASIN TODAY THROUGH TUESDAY. THIS STORM WILL 
INTENSIFY AS IT MOVES ACROSS SOUTHERN UTAH. A COOL AIRMASS WILL
THEN REMAIN IN PLACE THROUGH LATE WEEK.

&&

.DISCUSSION...THE UPPER TROUGH EXTENDING FROM THE NR ROCKIES THROUGH
NRN CA WILL TURN EAST BEGINNING THIS AFTERNOON...THEN ACROSS UTAH
TONIGHT THROUGH EARLY TUESDAY. THE VORTICITY LOBE MOVING THROUGH
THE SRN END OF THE TROUGH WILL BE THE FEATURE TO WATCH ACROSS SRN
UT LATER TODAY. GOOD BAROCLINIC STRUCTURE INDICATED IN THE BASE OF
THE TROUGH WITH SOLID DYNAMIC LIFT AND DEEP LAYER COLD AIR MOVING
INTO THE BASIN. LOOKING AT DEEP/STRONG UPWARD MOTION WITH THIS
SYSTEM LATER TODAY AS THE NOSE OF THE 140+ KT JET MOVES INTO WRN
AZ. RAPID LEE SIDE CYCLOGENESIS OFF OF THE CNTRL/SRN SIERRAS THIS
AFTERNOON...WITH FURTHER DEEPENING OF THE SURFACE LOW AS IT MOVES
EAST A REFLECTION OF THE STRONG UPWARD MOTIONS. SRN UTAH STILL
LOOKS TO GET HAMMERED BY THIS STORM...WITH CNTRL/ERN UTAH ALSO
GETTING A FAIR AMOUNT OF PRECIP. WILL MAINTAIN ALL WARNINGS
CURRENTLY IN EFFECT. UP NORTH LIGHT SNOW TODAY RESULTING WITH LOW-
LEVEL WARM ADVECTION WILL TURN HEAVIER TONIGHT AS THE NRN PORTION
OF THE TROUGH MOVES THROUGH THE REGION. WILL ALSO MAINTAIN
HIGHLIGHTS IN EFFECT FOR THE NORTH.

A LONG NORTHERLY FETCH WILL DEVELOP OUT OF THE ARCTIC MIDWEEK.
VERY COLD AIR WILL POUR SOUTH INTO THE NRN ROCKIES...WITH SOME OF
THIS COLD AIR SPILLING INTO THE RN UTAH VALLEYS. THIN SNOW COVER
COMBINED WITH THE COLDER AIR COULD LEAD TO THE COLDEST
TEMPERATURES OF THE SEASON TO DATE. HEAVIER SNOW COVER AND MINIMAL
CLOUD COVER WILL ALSO LEAD TO VERY COLD TEMPS DOWN SOUTH THROUGH
THE BALANCE OF THE WEEK. 

MOIST WESTERLIES WILL FINALLY PUNCH THROUGH THE REGION TOWARDS THE
WEEKEND. OVERRUNNING PRECIP THE THING TO WATCH THIS WEEKEND...WITH
ENHANCED PRECIP POSSIBLE AS EMBEDDED DISTURBANCES RIPPLE THROUGH
UTAH. TEMPS WILL MODERATE AT THE HIGHER ELEVATIONS...WITH VALLEYS
GENERALLY REMAINING COLD/CLOUDY WITH PERIODIC LIGHT SNOW.

&&

.AVIATION...CIGS ARE EXPECTED TO REMAIN BELOW 6000FT AGL THROUGH THE 
DAY TODAY AT KSLC...WITH SNOW SHOWERS FOCUSING OVER AND AROUND THE 
SURROUNDING TERRAIN. A 30 PERCENT CHANCE EXISTS THAT MVFR 
VISIBILITIES WILL OCCUR IN SNOW SHOWERS THIS AFTERNOON...BUT 
SNOW WILL NOT BE MUCH OF A CONCERN UNTIL THE OVERNIGHT HOURS
TONIGHT. CONCERN FOR IFR CONDITIONS IN LIGHT SNOW EXISTS LATE
TONIGHT AND THROUGHOUT THE DAY TUESDAY. TOTAL ACCUMULATIONS LOOK
TO FALL IN THE 1 TO 3" RANGE AT THE TERMINAL...BUT COLD RUNWAY
TEMPS WILL ALLOW ACCUMULATION TO ALL UNTREATED SURFACES.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...WINTER STORM WARNING UNTIL 4 PM TUESDAY FOR UTZ008-UTZ009-UTZ010-
     UTZ517-UTZ518.

     WINTER STORM WARNING UNTIL NOON TUESDAY FOR UTZ014-UTZ015-UTZ016.

     WINTER STORM WARNING UNTIL 6 AM TUESDAY FOR UTZ011-UTZ012-UTZ013-
     UTZ019-UTZ020-UTZ021.

     WINTER WEATHER ADVISORY UNTIL 4 PM TUESDAY FOR UTZ003-UTZ004-
     UTZ006.

WY...NONE.

&&

$$

PUBLIC...CONGER
AVIATION...MERRILL

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