000
FXUS65 KSLC 070341
AFDSLC
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
841 PM MST TUE JAN 6 2009
.SYNOPSIS...A MOIST NORTHWEST FLOW WILL REMAIN ACROSS THE AREA
TONIGHT. HIGH PRESSURE WILL MOVE INTO THE GREAT BASIN WEDNESDAY
THEN EAST THURSDAY AHEAD OF THE THE NEXT PACIFIC WEATHER SYSTEM.
THIS SYSTEM WILL PUSH A COLD FRONT THROUGH UTAH THURSDAY NIGHT AND
FRIDAY.
&&
.DISCUSSION...MOIST NORTHWEST FLOW WARM ADVECTION PERSISTS ACROSS
THE NORTHERN FORECAST AREA THIS EVENING. PRECIP HAS BEEN WAXING
AND WANING WITH SMALL WAVES IN THE FLOW OVER THE LAST SEVERAL
HOURS AND IS INCREASING AGAIN AT THIS TIME.
SURFACE TEMPS HAVE CONTINUED TO SLOWLY RISE ALONG THE WASATCH
FRONT ALTHO THERE ARE STILL COLD POCKETS BELOW FREEZING REMAINING.
THIS WILL LIMIT THE IMPACT OF ADDITIONAL SNOWFALL ON ROAD SURFACES
ALTHO HEAVIER EPISODES OF PRECIP OVER THE NEXT FEW HOURS COULD
STILL ACCUMULATE. WILL KEEP ADVISORIES GOING AT THIS TIME FOR THIS
CONTINUED THREAT.
NEW NAM DOES SHOW WARM ADVECTION LIFT WINDING DOWN AFTER 06Z AND
EXPECT MOST VALLEY PRECIP TO END DURING THE EARLY MORNING HOURS
WITH THE MTS DRIBBLING ON FOR A LITTLE LONGER. IF ANY CLEARING
OCCURS...FOG IS A DISTINCT POSSIBILITY AND WILL UPDATE TO ADD TO
THE NORTHWESTERN ZONES.
IT IS DIFFICULT TO DETERMINE JUST HOW MUCH MIXING WILL OCCUR IN
THE NORTHWESTERN BASINS TOMORROW AFTERNOON BUT WITH TEMPS
REMAINING MILD OVERNIGHT...IT SHOULD NOT BE HARD TO GET INTO THE
MID TO UPPER 30S EVEN IN THE MOST POORLY MIXED AREAS. THE BIGGEST
LIMITING FACTOR WILL BE THE EXISTING SNOW COVER AND LINGERING LOW
CLOUDS OR FOG MAY ALSO HOLD TEMPS DOWN.
THIS MAY NOT BE AS MUCH OF A ISSUE THU AS SOUTHERLY LOW LEVEL
FLOW PICKS UP AHEAD OF THE NEXT COLD FRONT FOR THU NIGHT AND THE
LOW LEVELS DRY OUT A BIT.
THE NEW NAM STILL INDICATES A FROPA THU EVE WITH A BAND OF SNOW
ACCOMPANYING THE FRONT WITH SNOW SHOWERS LINGERING INTO FRI.
WILL UPDATE TO ADD FOG AS DISCUSSED ABOVE BUT NO OTHER CHANGES
PLANNED AT THIS TIME.
&&
.AVIATION...SURFACE WINDS AT THE SLC TERMINAL ARE EXPECTED TO STAY
OUT OF THE SOUTHEAST THROUGH THE NIGHT. MORE VARIABLE WINDS COULD
OCCUR AT TIMES DUE TO SHOWER ACTIVITY. PERIODS OF MVFR CONDITIONS IN
SNOW SHOWERS WILL BE POSSIBLE THROUGHOUT THE NIGHT. A 20 PERCENT
CHANCE OF IFR CONDITIONS IS POSSIBLE WITH HEAVIER SNOW MOVING OFF
THE GREAT SALT LAKE. AS TEMPERATURES WARM ALOFT...PRECIPITATION
COULD BECOME RAIN OR A RAIN-SNOW MIX.
&&
.SLC WATCHES/WARNINGS/ADVISORIES...
UT...WINTER WEATHER ADVISORY UNTIL 4 AM WEDNESDAY FOR UTZ001-UTZ002-
UTZ003-UTZ004-UTZ006-UTZ007-UTZ008.
WY...NONE.
&&
$$
PUBLIC...WILENSKY
AVIATION...YOUNG
FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)
