Heavy Snow in Utah, January 22, 2002

UTAH AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
900 PM MST MON JAN 21 2002

.SYNOPSIS...A COLD PACIFIC TROUGH WILL SETTLE OVER THE GREAT BASIN
LATE TONIGHT AND LINGER INTO WEDNESDAY. HIGH PRESSURE WILL RETURN FOR
THURSDAY AND FRIDAY.

.DISCUSSION...SYSTEM STILL ON TRACK FOR WHAT WILL PROBABLY END UP A
MODERATE SNOW EVENT FOR THE NORTHERN HALF OF OUR AREA.  COLD FRONT
HAS PUSHED INTO NORTHWEST UT AND PROBABLY EXTENDS FROM NEAR
SNOWVILLE...ON I-84 JUST SOUTH OF THE ID BORDER...TO NEAR EKO.
HOWEVER THE BETTER BAROCLINIC BOUNDARY APPEARS TO BE LAGGING ABOUT
50 MILES BEHIND THE SURFACE FRONT.  THE SOUTHWARD MOVEMENT OF BOTH
OF THESE HAS SLOWED OVER THE LAST SEVERAL HOURS WHICH ISNT A
SURPRISE AS THEY ARE BECOMING PRETTY MUCH PARALLEL TO THE UPPER
LEVEL FLOW.  SO WHILE WE MAY GET A BRIEF BURST OF WEATHER WITH THE
SURFACE COLD FRONT THERE COULD BE A SEVERAL HOUR DELAY AFTER THAT
BEFORE THE MORE SIGNIFICANT SNOW ARRIVES.  TEMPTATION IS TO TRY TO
TOUCH UP THE FORECASTS TO ADJUST TIMING TO BE A BIT SLOWER BUT
RELUCTANT TO DO THAT WITH A SHORTWAVE JUST ABOUT TO CROSS THE ID/OR
BORDER AND MOVING RAPIDLY EAST.  THAT SHOULD SERVE TO NUDGE THE
BOUNDARIES SOUTH A BIT AS IT MOVES PAST.  SO BELIEVE WE WILL LEAVE
THE FORECASTS AS THEY STAND AND KEEP THE SNOW ADVISORIES IN EFFECT.

BIGGEST CONCERN IS THAT THE UPPER LEVEL BAROCLINIC ZONE THAT IS
LAGGING THE FRONT WILL LIKELY STALL SOMEWHERE OVER CENTRAL UT EVEN
THOUGH THE SURFACE FRONT MAY CONTINUE SOUTHWARD.  WHERE IT STALL
WILL BE DETERMINED BY HOW MUCH MORE DIGGING THERE IS IN THE TROF.
IT MAY NOT DIG A LOT FARTHER FOR A WHILE.  THERE IS A SPEED MAX
ABOUT TO ROUND THE BOTTOM OF THE TROF AND TYPICALLY THAT WOULD HALT
THE DEEPENING UNTIL THE NEXT JET IMPULSE DIGS DOWN THE BACK.  THE
ETA SHOWS THIS SPEED MAX TO SOME EXTENT BUT SEEMS TO BE SEVERAL
HOURS TOO SLOW IN ITS POSITION.  SO IT MAY BE DIGGING THE TROF A
LITTLE TOO MUCH.  THAT COULD LEAVE THE BAROCLINIC BOUNDARY STUCK
SOMEWHERE OVER THE CENTRAL OR SOUTHERN WASATCH FRONT.  IF THAT
HAPPENS SOME OF THE URBAN AREA COULD GET WARNING LEVEL AMOUNTS OF
SNOW.  BUT WHERE THAT MIGHT END UP BEING WOULD BE LITTLE MORE THAN A
GUESS AT THIS POINT. IT WILL BE BEST TO LEAVE THAT TO SHORT TERM
FORECASTING AND STATEMENTS.  SO WILL LIVE WITH THE MESSAGE THAT THE
MORNING COMMUTE WILL BE A MESS BECAUSE OF SNOW AND BELIEVE THE
FORECASTS AMOUNTS WILL BE ABOUT RIGHT FOR THE MAJORITY OF THE AREA.

SLC +988  CDC 4544  WILENSKY

.SLC...SNOW ADVISORIES FOR MOST NORTHERN PORTIONS TONIGHT...AND
NRN MOUNTAINS THRU TUE NIGHT...SEE LATEST SLCWSWSLC.