874 FXUS65 KSLC 011131 AFDSLC AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SALT LAKE CITY UT 431 AM MST MON DEC 1 2008 .SYNOPSIS...A RIDGE OF HIGH PRESSURE WILL PREVAIL ACROSS THE REGION TODAY. THE NEXT STORM SYSTEM WILL DIVE SOUTHEAST FROM THE PACIFIC NORTHWEST AND MOVE ACROSS THE NORTHERN HALF OF THE AREA TUESDAY AND INTO COLORADO TUESDAY NIGHT. RIDGING WILL DEVELOP FOR THE END OF THE WORK WEEK. && .DISCUSSION...THE RIDGE OF HIGH PRESSURE WILL FINALLY MOVE OVERHEAD TODAY PUSHING THE LOW TO MID LEVEL MOISTURE THAT HAS BLANKETED A GOOD PORTION OF THE AREA THE PAST COUPLE OF DAYS EAST OF THE REGION. SOME MORNING PATCHY FOG AND STRATUS IN THE CACHE VALLEY...NORTHERN MOUNTAIN VALLEYS AND SOUTHWEST WYOMING WILL DISSIPATED RAPIDLY THIS MORNING AS WINDS MIX DOWN AND THIN HIGH CLOUDS MOVE IN. A STRONG INVERSION STILL REMAINS IN PLACE TODAY WITH TEMPERATURES IN THE MOUNTAINS EXPECTED TO REACH NEAR 50 DEGREES. MEANWHILE TEMPERATURES IN THE VALLEYS AND FOOTHILLS WILL BE QUITE VARIABLE DEPENDING ON ELEVATION RANGING FROM NEAR 50 IN SOME AREAS TO EVEN THE LOW 60S ELSEWHERE. NOT QUITE WHAT YOU WOULD EXPECT FOR THE FIRST DAY OF DECEMBER. HOWEVER...A STORM SYSTEM WILL MOVE INTO EXTREME NORTHERN UTAH TUESDAY MORNING AND OVER THE NORTHERN HALF OF THE CWA BY AFTERNOON. THIS IS A FAST MOVING SYSTEM BUT IT HAS GOOD POTENTIAL TO PRODUCE PRECIPITATION ACROSS THE NORTH DUE TO A COMBINATION OF 300-500MB DIV/Q...300-500MB DIFFERENTIAL VORTICITY ADVECTION...UNSTABLE UP TO NEAR 600MB AND PW VALUES OF 0.40 TO 0.45. THIS SYSTEM DID TAP SOME SUB TROPICAL MOISTURE ABOUT 36 HOURS AGO SO BASED ON THESE ATTRIBUTES HAVE BOOSTED POPS TO LIKELY FOR MOST NORTHERN VALLEYS AND CATEGORICAL FOR THE MOUNTAINS. HAVE NOT GONE WITH ANY HEADLINES AT THIS TIME AS AMOUNTS WILL LIKELY BE MORE IN THE ADVISORY LEVEL FOR THE MOUNTAINS AND TEMPERATURES AT 700 MB SUPPORT A RAIN SNOW MIXTURE IN THE VALLEYS. BENCH LOCATIONS COULD PICK UP A WET INCH OF SNOW ON GRASSY SURFACES. THE COMBINATION OF 30-40KT 700 MB NORTHWEST WINDS AND 7-8 MB SURFACE GRADIENT BETWEEN PRICE AND WENDOVER WILL RESULT IN BREEZY TO WINDY CONDITIONS ACROSS MOST NORTHERN AREAS TUESDAY AFTERNOON AND EVENING. SOUTHERN AREAS WILL NOT SEE ANY PRECIPITATION BUT BEHIND THE COLD FRONT AFTERNOON NORTHWEST WINDS SHOULD BECOME BREEZY. A WEAK TROUGH IN THE NORTHERLY FLOW IS EXPECTED TO MOVE ACROSS THE GREAT BASIN REGION THURSDAY. HAVE LEANED TOWARDS THE EC ONCE AGAIN ON THIS FEATURE WHICH IS QUITE A BIT WEAKER THAN THE GFS AND THEREFORE HAVE UNDERCUT POPS. A RIDGE WILL FORM AGAIN IN THE WAKE OF THIS TROUGH FOR THE END OF THE WEEK. TOWARDS THE END OF THE SEVEN DAY PERIOD A LOT OF UNCERTAINTY OCCURS OVER THE GULF OF ALASKA IN THE GFS MODEL WHERE THE STANDARD DEVIATION BETWEEN ENSEMBLE MEMBERS EXCEEDS 200 METERS. THEREFORE WITH LACK OF CONFIDENCE HAVE GONE WITH NEAR CLIMO POPS FOR MONDAY. && .AVIATION...VFR CONDITIONS WILL PREVAIL AT THE SLC TERMINAL THROUGH THE DAY WITH ONLY HIGH CLOUDS OVERSPREADING THE AREA. SOUTH WINDS ARE EXPECTED TO SHIFT TO THE NORTHWEST WITH THE LAKE BREEZE BETWEEN 21Z AND 23Z. HOWEVER...THERE IS A 20 PERCENT CHANCE THAT THE WINDS WILL REMAIN FROM THE SOUTH THROUGH THE ENTIRE DAY. && .SLC WATCHES/WARNINGS/ADVISORIES... UT...NONE. WY...NONE. && $$ PUBLIC...STRUTHWOLF AVIATION...GRAHAM FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT... HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)