Severe Thunderstorm Warning 4, NWS Salt Lake City, UT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
410 PM MDT SAT APR 17 2004

.SYNOPSIS...A COLD FRONT AND THE ASSOCIATED UPPER LEVEL TROUGH WILL
MOVE ACROSS UTAH TONIGHT THROUGH EARLY SUNDAY.  COOL AND UNSETTLED
WEATHER WILL REMAIN OVER THE AREA THROUGH NEXT WEEK.

&&

.DISCUSSION...VORTICITY MAX IN THE BASE OF THE TROUGH OVER CA
BEGINNING TO LIFT NE TOWARD UTAH LATE THIS AFTERNOON.  THIS
VORTICITY MAX WILL TRACK ACROSS SRN UTAH LATE TONIGHT/SUNDAY
MORNING...DRAGGING THE REST OF THE NOW WEAKENING TROUGH ACROSS THE
REMAINDER OF UTAH/ERN ID.

CONVECTION HAS BEEN ON THE INCREASE PAST COUPLE OF HOURS ACROSS WRN
UT/ERN NV.  THIS ACTIVITY HAS FOCUSED ON THE SURFACE TROUGH NEAR
THE UT/NV UNDERNEATH A RATHER STRONG JET SW-NE ACROSS UTAH.
CONVECTION SHOULD CONTINUE TO INCREASE THIS EVENING AS THE SRN CA
VORTICITY MAX APPROACHES.  BEST THREAT FOR PRECIP LIKELY BETWEEN
MIDNIGHT THROUGH EARLY AFTERNOON SUNDAY.  DYNAMICS ASSOCIATED WITH
THE TROUGH ALONG WITH COLDER AIR ALOFT WILL BRING WIDESPREAD PRECIP
TO THE MOUNTAINS AND PRIMARILY THE WRN/NRN VALLEYS DURING THAT
PERIOD.  OROGRAPHIC ENHANCEMENT COULD LEAD TO HEAVY SNOWFALL IN THE
NRN MOUNTAINS.  HAVE ISSUED A LATE-SEASON HEAVY SNOW WARNING FOR
THOSE ZONES FOR LATE TONIGHT THROUGH THE DAY SUNDAY.

A SECONDARY SHORTWAVE WILL RIPPLE THROUGH THE NRN GREAT BASIN LATE
MONDAY/MONDAY NIGHT.  THIS FEATURE DOESNT APPEAR PARTICULARLY
STRONG...BUT SHOULD BE ABLE TO GENERATE A LITTLE PRECIP FOR THE NRN
ZONES ON ITS WAY EAST.  A BETTER LOOKING SYSTEM HITS THE AREA
MIDWEEK.  THIS NEXT SYSTEM INITIALLY WEAKENS AS IT MOVES INTO THE
PACIFIC NW.  AMPLIFICATION OF THE PATTERN OVER THE ERN PACIFIC
ALLOWS THIS TROUGH TO DIG THROUGH THE BASIN...THEN CLOSE OFF NEAR
THE FOUR-CORNERS THURSDAY.  WILL LIKELY SEE A GOOD SHOT OF PRECIP
AS THIS FEATURES DIGS TO THE SE...BUT QUESTION WHETHER WE ARE
LOOKING AT A LONGER PRECIP EVENT THROUGH THURSDAY.  STILL CONCERNED
THAT THE LOW WILL CLOSE OFF A BIT FURTHER TO THE SE OVER THE SRN
ROCKIES OF NEW MEXICO.  IF THIS WERE TO HAPPEN...THEN ANY WRAP
AROUND PRECIP WOULD REMAIN OVER FAR ERN UT/COLORADO.  FOR NOW
PLAYED WITH UNCERTAINTY AND LEFT A THREAT OF PRECIP IN THE MIDWEEK
PERIOD.  RIDGING LATE IN THE WEEK SHOULD DRY/WARM THINGS A BIT
HEADING INTO THE WEEKEND.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...

UT...WINTER STORM WATCH NORTHERN MOUNTAINS TONIGHT AND SUNDAY
MORNING.
ID...WINTER STORM WATCH EXTREME SOUTHEAST MOUNTAINS TONIGHT AND
SUNDAY MORNING.
WY...NONE.
&&

CONGER

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
550 AM MDT SAT APR 17 2004

IDZ025-UTZ007>010-181400-
WASATCH MOUNTAINS I-80 NORTH-WASATCH MOUNTAINS SOUTH OF I-80-
WASATCH MOUNTAINS/IDAHO PORTION-WASATCH PLATEAU/BOOK CLIFFS-
WESTERN UINTA MOUNTAINS-
550 AM MDT SAT APR 17 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE MOUNTAINS OF NORTHERN UTAH
AND EXTREME SOUTHEAST IDAHO

.DAY ONE... TODAY

A COLD FRONT WILL MOVE ACROSS THE AREA THIS EVENING BRINGING WINTER
LIKE CONDITIONS TO THE MOUNTAINS OF NORTHERN UTAH AND EXTREME
SOUTHEAST IDAHO. SEE SLCWSWSLC FOR DETAILS ON WINTER STORM
WATCHES...WARNINGS...OR ADVISORIES.

.DAYS TWO THROUGH SEVEN... SUNDAY THROUGH FRIDAY

SNOW WILL CONTINUE INTO SUNDAY MORNING THEN TAPER OFF TO SHOWERS BY
AFTERNOON. A SERIES OF STORM IMPULSES WILL MOVE ACROSS THE AREA
THROUGH THE MIDDLE OF NEXT WEEK.  SIGNIFICANT MOUNTAIN SNOW IS
POSSIBLE AGAIN WEDNESDAY.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
120 PM MDT SAT APR 17 2004

IDZ024-025-UTZ001>011-014>017-WYZ021-180000-
CACHE VALLEY/IDAHO PORTION-CACHE VALLEY/UTAH PORTION-
CENTRAL AND SOUTHWEST MOUNTAINS-GREAT SALT LAKE DESERT AND MOUNTAINS-
NORTHERN WASATCH FRONT-SALT LAKE AND TOOELE VALLEYS-
SANPETE/SEVIER VALLEYS-SOUTHERN WASATCH FRONT-SOUTHWEST UTAH-
SOUTHWEST WYOMING-WASATCH MOUNTAIN VALLEYS-WASATCH MOUNTAINS I-
80 NORTH-WASATCH MOUNTAINS SOUTH OF I-80-
WASATCH MOUNTAINS/IDAHO PORTION-WASATCH PLATEAU/BOOK CLIFFS-
WEST CENTRAL UTAH-WESTERN UINTA BASIN-WESTERN UINTA MOUNTAINS-
120 PM MDT SAT APR 17 2004

...THUNDERSTORMS WITH STRONG GUSTY WINDS POSSIBLE TODAY...

A STORM SYSTEM MOVING FROM INTO UTAH FROM SOUTHERN CALIFORNIA
WILL PRODUCE SHOWERS AND THUNDERSTORMS ACROSS MUCH OF THE STATE THIS
AFTERNOON AND EVENING.  THESE SHOWERS AND THUNDERSTORMS WILL INCREASE
IN COVERAGE AND INTENSITY THROUGH THE AFTERNOON.

THE STRONGEST OF THESE THUNDERSTORMS WILL MAINLY BE LOCATED OVER THE
WESTERN TWO THIRDS OF THE STATE.  THESE THUNDERSTORMS ARE CAPABLE OF
PRODUCING STRONG WIND GUSTS AND DANGEROUS CLOUD TO GROUND LIGHTNING.
BRIEF HEAVY RAINFALLS ARE ALSO POSSIBLE.

WIND GUSTS FROM THUNDERSTORMS COULD APPROACH 55 MPH TODAY.  THESE
WIND GUSTS MAY CREATE HAZARDS TO HIGH PROFILE AND LIGHT WEIGHT
VEHICLES. IN ADDITION...AREAS OF BLOWING DUST NEAR OPEN AGRICULTURAL
AND RANGE LANDS COULD TAKE VISIBILITIES DOWN BELOW ONE HALF
MILE.

IF A STORM APPROACHES YOUR AREA...SECURE LOOSE AND LIGHT WEIGHT
OBJECTS AROUND YOUR HOME...AND THEN SEEK SHELTER INDOORS UNTIL THE
STORM PASSES.  PLEASE STAY TUNED TO LOCAL MEDIA OR NOAA WEATHER RADIO
FOR UPDATES ON THESE STORMS AS THE AFTERNOON PROGRESSES.