Winter Storm in Utah, December 29, 2002

UTAH AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
230 AM MST SUN DEC 29 2002

.SYNOPSIS...A COLD PACIFIC STORM SYSTEM WILL REACH THE UTAH AREA
EARLY THIS MORNING AND CONTINUE TO AFFECT THE REGION THROUGH MOST OF
TONIGHT. THE NEXT PACIFIC STORM WILL CROSS UTAH TUESDAY.

.DISCUSSION...STORM SYSTEM LOOKS SOMEWHAT FRACTURED AT THIS POINT.
COLD FRONT ALREADY THROUGH ELKO WITH SOME LIGHT SNOW BEHIND
FRONT. ELKO RADAR SHOWING ECHOES BUT MUST BE MOSTLY VIRGA AS HAVE NOT
SEEN MANY PRECIP REPORTS UNDER COVERAGE. THIS AREA LIKELY TO
INCREASE IN COVERAGE AS JET STREAK MOVING NORTHEAST ACROSS
SOUTHERN NEVADA SHOULD CAUSE DECENT LIFT AND ENHANCE PRECIP AS
SOMEWHAT OF A NEVADA CYCLOGENESIS DEVELOPS NEAR THE UTAH BORDER
EARLY THIS MORNING. HOWEVER, THIS BEGS THE QUESTION DOES MOST OF THAT
PRECIP SLIDE NORTHEAST INTO IDAHO AND WE ARE LEFT WITH MORE SHOWERY
TYPE CONDITIONS BEHIND THE FRONT WITH THE COMA CLOUD NORTH OF UTAH.
TEMPERATURES OF -10C AT 700 MB ALSO IS NOT ALL THAT COLD AND WE COULD
GET SOME BREAKS WHICH LEAVES US WITH TEMPERATURES NEAR 40 OR EVEN LOW
40S FOR HIGHS THIS AFTERNOON SO ACCUMULATING SNOW QUESTIONABLE. WILL
LEAN TOWARD BEST CHANCE OF SNOW ACCUMULATIONS TONIGHT.

MODELS KIND OF SHOW TWO PARTS TO THIS SYSTEM WITH THE SURFACE FRONT
COMING THROUGH NORTHERN UTAH THIS MORNING AND THE COLD POCKET AND 300
MB TROUGH MOVING THROUGH ABOUT 00Z MONDAY. THE 700 MB FLOW DOES NOT
BECOME FAVORABLE FOR TRUE UPSLOPE UNTIL LATER THIS AFTERNOON AND THEN
THROUGH MOST OF TONIGHT ALONG THE WASATCH FRONT. DESPITE THE 500 MB
TEMPERATURES WARMING RAPIDLY AFTER 00Z...THE OVERNIGHT PERIOD LOOKS
TO BE THE MOST FAVORABLE FOR ACCUMULATING SNOW WITH MOIST NORTHWEST
700 MB FLOW, GOOD OMEGA AND THETA-E.

IN THE NEAR TERM...WINDS AT 700 MB RELAX TO 20-25 KT BY 18Z...SO
EVEN THOUGH WINDY CONDITIONS ARE EXPECTED WITH THE SNOW THIS
MORNING WHICH IS NOT LIKELY TO BE VERY HEAVY, MOST OF THE STORM WILL
NOT HAVE STRONG WINDS. AMOUNTS ARE NOT EXPECTED TO REACH
WARNING CRITERIA EITHER AS MODELS ARE VERY STINGY WITH QPF. SO
THEREFORE WILL GO WITH A SNOW ADVISORY.

SOUTHERN UTAH NOT MUCH PRECIP EXPECTED SO NOT CONCERNED WITH ANY
NEED FOR STATEMENTS THERE.

BREAK EARLY MONDAY, BUT WARM ADVECTION LIKELY TO SPREAD SNOW OVER
NORTHERN WASATCH FRONT AND MOUNTAINS BY AFTERNOON WITH SOUTH WINDS
DEVELOPING ONCE AGAIN. AS RIDGE BUILDS ALONG WEST COAST TUESDAY
NIGHT, SYSTEM WILL STRENGTHEN AS IN COMES INTO UTAH SO LOOKS TO BE A
BETTER STORM WITH BETTER DEFINED COLD FRONT.

RIDGE BUILDS IN FOR LATER WEDNESDAY THROUGH SATURDAY.

SLC 762   CDC 421  STRUTHWOLF

.SLC...SNOW ADVISORIES NORTHERN UTAH AND SOUTHERN IDAHO TODAY INTO
       TONIGHT.

IDZ024-025-UTZ001>021-WYZ021-291400-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
700 AM MST SAT DEC 28 2002

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

.DAY ONE... TODAY

AN APPROACHING PACIFIC STORM...STILL OFF THE CALIFORNIA COAST THIS
MORNING...WILL LEAD TO VERY STRONG SOUTHERLY WINDS ACROSS THE
NORTHERN MOUNTAINS AND WESTERN VALLEYS TODAY.  A HIGH WIND WARNING
HAS BEEN ISSUED THROUGH TONIGHT FOR THESE AREAS.  SEE THE LATEST
SLCNPWSLC FOR THE DETAILS ON THIS HIGH WIND WARNING.

.DAYS TWO THROUGH SEVEN... SUNDAY THROUGH FRIDAY

THE TROUGH OFF THE CALIFORNIA COAST WILL MOVE THROUGH UTAH ON SUNDAY.
THE POTENTIAL FOR HEAVY SNOW EXISTS...PARTICULARLY FOR THE NORTHERN
MOUNTAINS AND THE ADJACENT VALLEYS.  A WINTER STORM WATCH HAS BEEN
ISSUED BEGINNING LATE TONIGHT FOR THE NORTHERN MOUNTAINS...AND
BEGINNING SUNDAY FOR THE VALLEYS.  BOTH WATCHES WILL EXTEND THROUGH
SUNDAY NIGHT.  SEE THE LATEST SLCWSWSLC FOR DETAILS ON THIS WINTER
STORM WATCH.

THE NEXT PACIFIC SYSTEM WILL MOVE THROUGH THE STATE TUESDAY.  THIS
SYSTEM DOES NOT LOOK AS STRONG AS THE SUNDAY STORM...BUT WILL STILL
PRODUCE SIGNIFICANT SNOW FOR AT LEAST THE NORTHERN MOUNTAIN
LOCATIONS.

.SPOTTER INFORMATION STATEMENT...

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

WCJIN-WYSW