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000
FXUS65 KGJT 202258
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
358 PM MST SAT DEC 20 2014

.SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT)
ISSUED AT 355 PM MST SAT DEC 20 2014

LATEST SATELLITE IMAGERY SHOWS PLENTY OF CLOUDS MOVING INTO THE
AREA FROM THE NW AS THE FIRST DISTURBANCE MOVES OVER THE
AREA...SETTING THE STAGE FOR TOMORROW. FOR THE REMAINDER OF THE
EVENING AND OVERNIGHT...MODELS PICKING UP ON SOME PRECIP FOR
AREAS MAINLY N OF THE SAN JUANS WITH A RAIN TO RAIN-SNOW MIX FOR
LOWER VALLEYS AND SOME ACCUMULATING SNOW FOR THE HIGHER
TERRAIN.  MAYBE 1 TO 3 INCHES...GENERALLY FOR THE NRN MTNS THOUGH
THE CENTRAL MTNS MIGHT SEE THAT MUCH TOO. HOWEVER...THESE AMTS
HAVE NOTHING ON WHAT WE CAN EXPECT STARTING TOMORROW.

THE JET STREAM THAT HAS STAYED TO OUR NORTH FOR QUITE SOME TIME
HAS FINALLY BEGUN TO DROP DOWN FROM THE NORTH AND ALSO BECOME A
BIT MORE MERIDIONAL THAN PREVIOUS RUNS. THIS PUTS WESTERN COLORADO
IN THE COLDER SECTOR WHILE ALSO KEEPING MUCH OF THE STATE IN THE
FAVORABLE LEFT EXIT REGION OF THE JET. THIS REGION WILL CAUSE
PLENTY OF UPLIFT FOR EFFICIENT SNOW. GUIDANCE ALSO SHOWS PLENTY OF
MOISTURE IN THE AREA WITH HIGH SPECIFIC HUMIDITIES IN PLACE. ALL
THE ABOVE MEANS WE ARE PRIMED FOR SOME ACCUMULATING SNOWFALL.

SPOTTY PRECIP WILL START SUNDAY MORNING BEFORE BECOMING MORE
STEADY NOON ONWARDS WITH THE HEAVIEST PRECIP EXPECTED FROM SUNDAY
AFTERNOON THROUGH MONDAY MORNING. SOME HIGHLIGHTS INCLUDE A FOOT
TO OVER 2 FEET OF SNOW FOR THE PARK/GORE AND ELKHEAD MTNS MAINLY
DUE TO A WRLY FLOW THAT WILL BECOME NRLY AS THE STORM EVOLVES ALLOWING
SNOW TO KEEP PILING UP. SIMILAR AMOUNTS ARE ALSO POSSIBLE FOR THE
CENTRAL MTNS. THE NRN PORTIONS OF THE WRN SAN JUANS WILL LIKELY
SEE OVER A FOOT BUT NOT SOLD ON SRN PORTIONS SO LEFT IN ADVISORY
FOR NOW...LATER SHIFTS MAY NEED TO UPGRADE. ISSUED A WARNING FOR
THE CRAIG/MEEKER/HAYDEN AREA WITH 6 TO 10 INCHES OF SNOW POSSIBLE
THOUGH AREAS IN THE EAST AND SOUTH PORTIONS OF THE ZONE WILL SEE
THE HIGHEST AMOUNTS. ALSO ANTICIPATE WARNING AMTS EAST OF RIFLE
ALONG I-70 INCREASING AS YOU TRAVEL TO VAIL PASS. FOR RIFLE AND
AREAS WEST ALONG I-70 THROUGH DEBEQUE CANYON MAY SEE 2 TO 4 INCHES
THOUGH TEMPS WILL BE HOVERING RIGHT AROUND FREEZING.

AS THE 140KT+ JET MOVES OVERHEAD...SOME OF THESE WINDS ARE
EXPECTED TO MIX DOWN CAUSING GUSTS ANYWHERE FROM 30 TO POSSIBLY 50
MPH (AT THE HIGHEST ELEVATIONS) CREATING WHITEOUT CONDITIONS FROM
TIME TO TIME. IMPORTANT TO MENTION THAT MOST OF THESE WINDS WILL
BE FELT AT HIGHER ELEVATIONS THOUGH WINDS ALONG THE CO/WY BORDER
COULD GET FAIRLY BREEZY FROM TIME TO TIME SUNDAY.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 355 PM MST SAT DEC 20 2014

SNOW CONTINUES MONDAY AS THE 140-150KT CORE OF THE 300 MB JET MOVES
FROM NORTHEASTERN UT INTO SOUTHWESTERN CO...AND A 700 MB COLD FRONT
PUSHES SOUTH ACROSS THE FORECAST AREA. SNOW WILL BE HEAVY AT TIMES
MONDAY...AND TRAVEL CONDITIONS OVER THE MOUNTAINS WILL BE POOR.
WITH 700 MB WINDS OF 40-50 KTS ACROSS THE NORTH...EXPECT STRONG
WINDS OVER THE MTNS CREATING AREAS OF BLOWING SNOW. A FEW AREAS MAY
EXPERIENCE NEAR BLIZZARD CONDITIONS WITH GUSTS EXCEEDING 45 MPH...
ESPECIALLY ABOVE TIMBERLINE ACROSS THE PARK AND GORE RANGES AND
POSSIBLY AS FAR SOUTH AS VAIL PASS ON MONDAY. FOR THE ERN UINTA
MTNS...CONCERN ABOUT SNOW AND BLOWING SNOW WITH THE FRONTAL PASSAGE
AND UPPER JET AND ITS IMPACT ON TRAVEL PROMPTED THE WINTER STORM
WATCH THERE DESPITE SNOW AMOUNTS ON THE LOW SIDE. LOWERED MAX TEMPS
ON MONDAY WITH ABUNDANT CLOUD COVER AND COLDER AIR MOVING IN.

THE NORTHWEST OROGRAPHIC FLOW BECOMES NORTHERLY MONDAY AFTERNOON...
WHICH THEN PERSISTS THROUGH MONDAY EVENING. THE VERY MOIST DENDRITIC
SNOW GROWTH ZONE LOWERS TO OR BELOW MTN TOP LEVEL IN COLD ADVECTION
BEHIND THE FRONT TO TAKE FULL ADVANTAGE OF THE OROGRAPHIC LIFT. A
BIT CONCERNED THAT THE 12Z Q-G DIAGNOSTICS FAVORED LARGE-SCALE
DOWNWARD MOTION MONDAY...THOUGH. NORTH FLOW AND LOW-LEVEL MOISTURE
BANKED UP AGAINST THE FLATTOPS/ROAN PLATEAU SHOULD KEEP SNOW IN THE
CRAIG AND MEEKER AREAS MONDAY EVENING...BUT WILL NOT BE AS FAVORABLE
FOR THE STEAMBOAT SPGS.

THE UPPER JET AND LOW LEVEL MOISTURE SEEM SLOWER TO PUSH EAST MONDAY
NIGHT AND TUESDAY THAN EARLIER MODEL RUNS. CHANCE OF SNOW PERSISTS
IN THE NRN AND CENTRAL CO MTNS TUE. A LULL IN THE PRECIPITATION
EXPECTED WEDNESDAY UNDER TEMPORARY RIDGING AS THE NEXT PACIFIC STORM
MOVES INTO WA/OR. GFS AND ECMWF CONTINUE TO PUSH IT ACROSS OUR AREA
CHRISTMAS DAY WHILE THE CANADIAN DIGS IT DOWN THE CA COAST WED
NIGHT AND NOT PREFERRED. BOTH GFS AND ECMWF CONTINUE THE TREND OF
THE WAVE BEING FLATTER AND A LITTLE FARTHER NORTH...THOUGH ECMWF
SEEMS TO VACILLATE WITH THE AMPLITUDE BETWEEN ITS EVENING AND
MORNING MODEL RUNS. WILL KEEP THE BETTER CHANCE OF PRECIPITATION
OVER THE NRN AND CENTRAL MTNS FOR NOW.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 355 PM MST SAT DEC 20 2014

MID LEVEL CEILINGS CONTINUE TO BE ON THE INCREASE WITH SOME LIGHT
SNOW BEING REPORTED AT KVEL AND A FEW MTN SITES. SOME MVFR
POSSIBLE OVERNIGHT FOR TAF SITES AS SOME -SN CONTINUES WITH A WEAK
DISTURBANCE MOVING OVERHEAD. BY 12Z EXPECT CONDITIONS TO
DETERIORATE SIGNIFICANTLY AS THE NEXT SYSTEM MOVES IN BRINGING
WIDESPREAD PRECIP WITH MVFR/IFR BEING COMMON THROUGH THE NEXT 24
HOURS. SRN AREAS INCLUDING KDRO...AND KCEZ WILL LIKELY SEE THE
BEST WEATHER WHILE THE REMAINING TAF SITES WILL SEE TIMES OF -SN
BRINGING CIGS AND VIS TO AIRFIELD MINS. MTN TOP WINDS WILL ALSO BE
GUSTY REACHING 30 TO 50 MPH AT TIMES. LOW LEVEL WIND SHEAR
CERTAINLY A POSSIBILITY AT KASE AND KEGE AS IS WIDESPREAD MTN
OBSCURATIONS. EXPECT THESE CONDITIONS TO CONTINUE FOR THE NEXT 24
HOURS.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...WINTER WEATHER ADVISORY FROM NOON SUNDAY TO MIDNIGHT MST MONDAY
     NIGHT FOR COZ014.

     WINTER STORM WARNING FROM 6 PM SUNDAY TO MIDNIGHT MST MONDAY
     NIGHT FOR COZ018.

     WINTER WEATHER ADVISORY FROM 6 PM SUNDAY TO 6 PM MST MONDAY FOR
     COZ017-019.

     WINTER STORM WARNING FROM 6 AM SUNDAY TO MIDNIGHT MST MONDAY
     NIGHT FOR COZ002-010-012.

     WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO MIDNIGHT MST
     MONDAY NIGHT FOR COZ004-013.

     WINTER WEATHER ADVISORY FROM NOON SUNDAY TO 6 PM MST MONDAY FOR
     COZ003.

     WINTER STORM WARNING FROM NOON SUNDAY TO 6 PM MST MONDAY FOR
     COZ007>009.

     WINTER STORM WARNING FROM 6 AM SUNDAY TO 6 PM MST MONDAY FOR
     COZ005.

UT...WINTER STORM WATCH FROM LATE SUNDAY NIGHT THROUGH MONDAY
     AFTERNOON FOR UTZ023.

&&

$$

SHORT TERM...TGR
LONG TERM...JAD
AVIATION...TGR





000
FXUS65 KGJT 202258
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
358 PM MST SAT DEC 20 2014

.SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT)
ISSUED AT 355 PM MST SAT DEC 20 2014

LATEST SATELLITE IMAGERY SHOWS PLENTY OF CLOUDS MOVING INTO THE
AREA FROM THE NW AS THE FIRST DISTURBANCE MOVES OVER THE
AREA...SETTING THE STAGE FOR TOMORROW. FOR THE REMAINDER OF THE
EVENING AND OVERNIGHT...MODELS PICKING UP ON SOME PRECIP FOR
AREAS MAINLY N OF THE SAN JUANS WITH A RAIN TO RAIN-SNOW MIX FOR
LOWER VALLEYS AND SOME ACCUMULATING SNOW FOR THE HIGHER
TERRAIN.  MAYBE 1 TO 3 INCHES...GENERALLY FOR THE NRN MTNS THOUGH
THE CENTRAL MTNS MIGHT SEE THAT MUCH TOO. HOWEVER...THESE AMTS
HAVE NOTHING ON WHAT WE CAN EXPECT STARTING TOMORROW.

THE JET STREAM THAT HAS STAYED TO OUR NORTH FOR QUITE SOME TIME
HAS FINALLY BEGUN TO DROP DOWN FROM THE NORTH AND ALSO BECOME A
BIT MORE MERIDIONAL THAN PREVIOUS RUNS. THIS PUTS WESTERN COLORADO
IN THE COLDER SECTOR WHILE ALSO KEEPING MUCH OF THE STATE IN THE
FAVORABLE LEFT EXIT REGION OF THE JET. THIS REGION WILL CAUSE
PLENTY OF UPLIFT FOR EFFICIENT SNOW. GUIDANCE ALSO SHOWS PLENTY OF
MOISTURE IN THE AREA WITH HIGH SPECIFIC HUMIDITIES IN PLACE. ALL
THE ABOVE MEANS WE ARE PRIMED FOR SOME ACCUMULATING SNOWFALL.

SPOTTY PRECIP WILL START SUNDAY MORNING BEFORE BECOMING MORE
STEADY NOON ONWARDS WITH THE HEAVIEST PRECIP EXPECTED FROM SUNDAY
AFTERNOON THROUGH MONDAY MORNING. SOME HIGHLIGHTS INCLUDE A FOOT
TO OVER 2 FEET OF SNOW FOR THE PARK/GORE AND ELKHEAD MTNS MAINLY
DUE TO A WRLY FLOW THAT WILL BECOME NRLY AS THE STORM EVOLVES ALLOWING
SNOW TO KEEP PILING UP. SIMILAR AMOUNTS ARE ALSO POSSIBLE FOR THE
CENTRAL MTNS. THE NRN PORTIONS OF THE WRN SAN JUANS WILL LIKELY
SEE OVER A FOOT BUT NOT SOLD ON SRN PORTIONS SO LEFT IN ADVISORY
FOR NOW...LATER SHIFTS MAY NEED TO UPGRADE. ISSUED A WARNING FOR
THE CRAIG/MEEKER/HAYDEN AREA WITH 6 TO 10 INCHES OF SNOW POSSIBLE
THOUGH AREAS IN THE EAST AND SOUTH PORTIONS OF THE ZONE WILL SEE
THE HIGHEST AMOUNTS. ALSO ANTICIPATE WARNING AMTS EAST OF RIFLE
ALONG I-70 INCREASING AS YOU TRAVEL TO VAIL PASS. FOR RIFLE AND
AREAS WEST ALONG I-70 THROUGH DEBEQUE CANYON MAY SEE 2 TO 4 INCHES
THOUGH TEMPS WILL BE HOVERING RIGHT AROUND FREEZING.

AS THE 140KT+ JET MOVES OVERHEAD...SOME OF THESE WINDS ARE
EXPECTED TO MIX DOWN CAUSING GUSTS ANYWHERE FROM 30 TO POSSIBLY 50
MPH (AT THE HIGHEST ELEVATIONS) CREATING WHITEOUT CONDITIONS FROM
TIME TO TIME. IMPORTANT TO MENTION THAT MOST OF THESE WINDS WILL
BE FELT AT HIGHER ELEVATIONS THOUGH WINDS ALONG THE CO/WY BORDER
COULD GET FAIRLY BREEZY FROM TIME TO TIME SUNDAY.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 355 PM MST SAT DEC 20 2014

SNOW CONTINUES MONDAY AS THE 140-150KT CORE OF THE 300 MB JET MOVES
FROM NORTHEASTERN UT INTO SOUTHWESTERN CO...AND A 700 MB COLD FRONT
PUSHES SOUTH ACROSS THE FORECAST AREA. SNOW WILL BE HEAVY AT TIMES
MONDAY...AND TRAVEL CONDITIONS OVER THE MOUNTAINS WILL BE POOR.
WITH 700 MB WINDS OF 40-50 KTS ACROSS THE NORTH...EXPECT STRONG
WINDS OVER THE MTNS CREATING AREAS OF BLOWING SNOW. A FEW AREAS MAY
EXPERIENCE NEAR BLIZZARD CONDITIONS WITH GUSTS EXCEEDING 45 MPH...
ESPECIALLY ABOVE TIMBERLINE ACROSS THE PARK AND GORE RANGES AND
POSSIBLY AS FAR SOUTH AS VAIL PASS ON MONDAY. FOR THE ERN UINTA
MTNS...CONCERN ABOUT SNOW AND BLOWING SNOW WITH THE FRONTAL PASSAGE
AND UPPER JET AND ITS IMPACT ON TRAVEL PROMPTED THE WINTER STORM
WATCH THERE DESPITE SNOW AMOUNTS ON THE LOW SIDE. LOWERED MAX TEMPS
ON MONDAY WITH ABUNDANT CLOUD COVER AND COLDER AIR MOVING IN.

THE NORTHWEST OROGRAPHIC FLOW BECOMES NORTHERLY MONDAY AFTERNOON...
WHICH THEN PERSISTS THROUGH MONDAY EVENING. THE VERY MOIST DENDRITIC
SNOW GROWTH ZONE LOWERS TO OR BELOW MTN TOP LEVEL IN COLD ADVECTION
BEHIND THE FRONT TO TAKE FULL ADVANTAGE OF THE OROGRAPHIC LIFT. A
BIT CONCERNED THAT THE 12Z Q-G DIAGNOSTICS FAVORED LARGE-SCALE
DOWNWARD MOTION MONDAY...THOUGH. NORTH FLOW AND LOW-LEVEL MOISTURE
BANKED UP AGAINST THE FLATTOPS/ROAN PLATEAU SHOULD KEEP SNOW IN THE
CRAIG AND MEEKER AREAS MONDAY EVENING...BUT WILL NOT BE AS FAVORABLE
FOR THE STEAMBOAT SPGS.

THE UPPER JET AND LOW LEVEL MOISTURE SEEM SLOWER TO PUSH EAST MONDAY
NIGHT AND TUESDAY THAN EARLIER MODEL RUNS. CHANCE OF SNOW PERSISTS
IN THE NRN AND CENTRAL CO MTNS TUE. A LULL IN THE PRECIPITATION
EXPECTED WEDNESDAY UNDER TEMPORARY RIDGING AS THE NEXT PACIFIC STORM
MOVES INTO WA/OR. GFS AND ECMWF CONTINUE TO PUSH IT ACROSS OUR AREA
CHRISTMAS DAY WHILE THE CANADIAN DIGS IT DOWN THE CA COAST WED
NIGHT AND NOT PREFERRED. BOTH GFS AND ECMWF CONTINUE THE TREND OF
THE WAVE BEING FLATTER AND A LITTLE FARTHER NORTH...THOUGH ECMWF
SEEMS TO VACILLATE WITH THE AMPLITUDE BETWEEN ITS EVENING AND
MORNING MODEL RUNS. WILL KEEP THE BETTER CHANCE OF PRECIPITATION
OVER THE NRN AND CENTRAL MTNS FOR NOW.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 355 PM MST SAT DEC 20 2014

MID LEVEL CEILINGS CONTINUE TO BE ON THE INCREASE WITH SOME LIGHT
SNOW BEING REPORTED AT KVEL AND A FEW MTN SITES. SOME MVFR
POSSIBLE OVERNIGHT FOR TAF SITES AS SOME -SN CONTINUES WITH A WEAK
DISTURBANCE MOVING OVERHEAD. BY 12Z EXPECT CONDITIONS TO
DETERIORATE SIGNIFICANTLY AS THE NEXT SYSTEM MOVES IN BRINGING
WIDESPREAD PRECIP WITH MVFR/IFR BEING COMMON THROUGH THE NEXT 24
HOURS. SRN AREAS INCLUDING KDRO...AND KCEZ WILL LIKELY SEE THE
BEST WEATHER WHILE THE REMAINING TAF SITES WILL SEE TIMES OF -SN
BRINGING CIGS AND VIS TO AIRFIELD MINS. MTN TOP WINDS WILL ALSO BE
GUSTY REACHING 30 TO 50 MPH AT TIMES. LOW LEVEL WIND SHEAR
CERTAINLY A POSSIBILITY AT KASE AND KEGE AS IS WIDESPREAD MTN
OBSCURATIONS. EXPECT THESE CONDITIONS TO CONTINUE FOR THE NEXT 24
HOURS.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...WINTER WEATHER ADVISORY FROM NOON SUNDAY TO MIDNIGHT MST MONDAY
     NIGHT FOR COZ014.

     WINTER STORM WARNING FROM 6 PM SUNDAY TO MIDNIGHT MST MONDAY
     NIGHT FOR COZ018.

     WINTER WEATHER ADVISORY FROM 6 PM SUNDAY TO 6 PM MST MONDAY FOR
     COZ017-019.

     WINTER STORM WARNING FROM 6 AM SUNDAY TO MIDNIGHT MST MONDAY
     NIGHT FOR COZ002-010-012.

     WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO MIDNIGHT MST
     MONDAY NIGHT FOR COZ004-013.

     WINTER WEATHER ADVISORY FROM NOON SUNDAY TO 6 PM MST MONDAY FOR
     COZ003.

     WINTER STORM WARNING FROM NOON SUNDAY TO 6 PM MST MONDAY FOR
     COZ007>009.

     WINTER STORM WARNING FROM 6 AM SUNDAY TO 6 PM MST MONDAY FOR
     COZ005.

UT...WINTER STORM WATCH FROM LATE SUNDAY NIGHT THROUGH MONDAY
     AFTERNOON FOR UTZ023.

&&

$$

SHORT TERM...TGR
LONG TERM...JAD
AVIATION...TGR




000
FXUS65 KGJT 201746
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1046 AM MST SAT DEC 20 2014

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 410 AM MST SAT DEC 20 2014

HAND ANALYSIS TONIGHT INDICATES RIDGE STILL OVER THE REGION...BUT
THE RIDGE IS BREAKING DOWN THIS MORNING AHEAD OF THE NEXT
SUBSTANTIAL WEATHER SYSTEM. A FEW RETURNS ARE SHOWING UP ON RADAR
THIS MORNING...BUT UNLIKE YESTERDAY MORNING...THIS IS JUST LIKELY
MID LEVEL CLOUDS SHOWING UP MIXED IN WITH A FEW ELEVATED SHOWERS.
THE SHORT TERM MODELS (RAP AND HRRR) INDICATE SOME SCATTERED
SHOWERS DEVELOPING ON THE ROAN/TAVAPUTS THIS MORNING AND ACROSS
NORTHWEST COLORADO SO ADDED THOSE INTO THE POP GRIDS
TODAY...ESPECIALLY CONSIDERING BAGGS WY AND HEBER CITY UT ARE
RECEIVING LIGHT SNOW THIS MORNING. ATMOSPHERIC MOISTURE IS
DEFINITELY AVAILABLE WITH SPEC HUMIDITIES BACK UP TO 3G/KG THIS
MORNING...THOUGH MOISTURE IS ELEVATED WITH DWPT DEPRESSIONS LARGER
THIS MORNING THAN THE LAST FEW DAYS WITHOUT THE LOW/SFC LEVEL
MOISTURE.

70KT UPPER LEVEL JET SUPPORT MAKES ITS WAY INTO THE FORECAST AREA
FROM THE WEST WHICH WILL SLOWLY INCREASE WINDS AT HIGHER TERRAIN
ACROSS ELEVATED PARTS OF NE UT AND NW CO AND AID IN UPPER LEVEL
DIVERGENCE TODAY. EVEN STRONGER (100KT) JET STREAK BLAZES THROUGH
ON SUNDAY AS THE FIRST HEAVIER PRECIPITATION IS EXPECTED TO BEGIN
IN NORTHWEST AND NORTH CENTRAL COLORADO. LOW LEVEL MOISTURE WILL
INCREASE ACROSS NE UT AND NW CO TODAY...THEN ACROSS THE REST OF
THE FORECAST AREA ON SUNDAY IN WARM AIR ADVECTION. NOT EXPECTING
HIGH SNOW AMTS ACROSS THE EASTERN UINTAS AS WE ARE EXPECTING THIS
AREA TO BE SHADOWED DUE TO THE STRONG UPPER LEVEL WESTERLY
WINDS...THOUGH WILL NEED TO CONSIDER THE NEED FOR AN ADVISORY IF
CONDITIONS CHANGE.

THIS UPCOMING WINTER STORM WILL REALLY TAKE HOLD ON SUNDAY WHICH
WILL BE QUITE NOTICEABLE WITH NORTHWEST WINDS RAPIDLY INCREASING
SUNDAY MORNING OVER NE UT AND NW CO. SNOW ACROSS THE NORTH CENTRAL
AND CENTRAL MOUNTAINS OF WESTERN CO WILL INCREASE IN COVERAGE AND
INTENSITY ON SUNDAY AS WELL. BLOWING SNOW WILL DEFINITELY BECOME
AN ISSUE AT HIGHER TERRAIN AND DO EXPECT IT TO BE DIFFICULT TO
MEASURE SNOWFALL AMOUNTS FOR THIS STORM. SEE LONG TERM SECTION FOR
MORE DETAILS ON THIS STORM DEVELOPMENT.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 410 AM MST SAT DEC 20 2014

...MAJOR WINTER STORM WILL CONTINUE TO BRING HEAVY SNOW AND
BLOWING SNOW TO THE MOUNTAINS OF WESTERN COLORADO THROUGH
MONDAY...

STRONG UPPER LEVEL JET WILL BE MOVING OVERHEAD SUNDAY NIGHT AND
MONDAY WITH H3 SPEEDS CLOCKING IN NEAR 140 KTS BY LATE MONDAY
AFTERNOON. THE FORECAST AREA WILL BE IN PRIME POSITION FOR
ENHANCED JET DYNAMICS FOR AT LEAST 18 HOURS BEGINNING SUNDAY
NIGHT AND THROUGH THE DAY ON MONDAY. PLENTY OF PACIFIC MOISTURE
WILL BE AVAILABLE AND WITH TEMPS IN FAVORABLE DENDRITIC GROWTH
ZONE OVERNIGHT SUNDAY THROUGH MONDAY...EXPECT HEAVY SNOWFALL WILL
NOT BE A PROBLEM WITH HIGH CONFIDENCE THAT MOST OF THE MOUNTAINS
IN WESTERN COLORADO WILL BE MEASURING SNOWFALL WITH A YARD STICK
BY THE TIME MONDAY EVENING ROLLS AROUND. WILL STILL BE CONTENDING
WITH A SHOT OF WAA ON SUNDAY WHICH MAY SLOW THINGS DOWN A
BIT...BUT COOLING ARRIVES SUNDAY NIGHT INTO THE DAY ON MONDAY AS
THE JET SHIFTS OVERHEAD.

A FEW AREAS MAY EXPERIENCE NEAR BLIZZARD CONDITIONS WITH GUSTS
EXCEEDING 45 MPH...ESPECIALLY ABOVE TIMBERLINE ACROSS THE PARK AND
GORE RANGES AND POSSIBLY AS FAR SOUTH AS VAIL PASS ON MONDAY.
SHARP GRADIENT TO THE HEAVY SNOW IS EXPECTED AND THE EXACT
POSITIONING OF THE JET WILL PLAY A BIG ROLE IN THE EVENTUAL
OUTCOME. OROGRAPHIC WIND FIELDS SHOWING SOME BEND TO A MORE
NORTHERLY COMPONENT ON MONDAY WHICH WOULD SLOW SNOW POTENTIAL
ACROSS THE NORTHERN MOUNTAINS...BUT SHIFT THINGS INTO THE CENTRAL
MOUNTAINS NEAR ASPEN...THUS THE EXPANSION OF HIGHLIGHTS TO
INCLUDE THE GRAND MESA AND ZONE 12 NEAR CRESTED BUTTE AND GOTHIC.

WITH CONFIDENCE HIGH AND HOLIDAY TRAVEL UNDERWAY...HAVE ISSUED
WARNINGS AND ADVISORIES FOR ALL OF THE MOUNTAINS IN WESTERN
COLORADO. HIGHER VALLEYS WILL ALSO BE GETTING INTO THE ACTION
SUNDAY AFTERNOON THROUGH MONDAY AND WILL EXPAND THE WATCH TO
INCLUDE CRAIG AND GUNNISON WHERE WE ARE GENERATING 6 PLUS INCHES
OF SNOW THROUGH THAT 24 HOUR PERIOD.

ADDITIONAL CONCERNS ACROSS NORTHEAST UTAH AND EXTREME NORTHWEST
COLORADO WILL BE WINDS WITH H7 SPEEDS CLOCKING IN AROUND 50-60KTS
BY LATE MONDAY AFTERNOON. FOOTPRINT OF THE STRONGEST WINDS ARE
CONFINED TO A NARROW REGION OF OUR FORECAST AREA...GENERALLY NORTH
OF THE EASTERN UINTA MOUNTAINS IN NORTHEAST UTAH INTO EXTREME
NORTHWEST COLORADO NORTH OF DINOSAUR NATIONAL MONUMENT. LATER
SHIFTS WILL NEED TO EVALUATE POTENTIAL FOR WIND OR WINTER
HIGHLIGHTS...BUT CONFIDENCE IN THE SNOW THROUGH THIS AREA WAS NOT
AS HIGH AND WE STILL HAVE TIME DO WORK OUT THE FINER DETAILS IN
THIS AREA.

THIS STORM WILL EXIT LATE MONDAY NIGHT AND TUESDAY WITH TRANSITORY
RIDGE SLIDING THROUGH TUESDAY NIGHT AND WEDNESDAY. THE POTENTIAL
STORM ON CHRISTMAS DAY IS ON SHAKEY GROUND AS THE LATEST GFS RUN
HAS BACKED OFF THE INTENSITY AND CONTINUES TO SHIFT BEST ENERGY
NORTH OF OUR FORECAST AREA. THE ECMWF HAS ALSO BACKED OFF
INTENSITY A BIT AND HAS STARTED TO SHIFT NORTH AS WELL. AFTER
COORDINATION WITH SURROUNDING OFFICES...WILL MAINTAIN HIGHER POPS
FOR NOW WITH FORECAST DIRECTED MORE TOWARD THE WETTER AND DEEPER
EC SOLUTION...WHICH HAS BEEN THE MOST CONSISTENT MODEL OVER THE
PAST FEW DAYS IN REGARDS TO THIS SYSTEM. BOTTOM LINE IS THAT
CONDITIONS WILL REMAIN UNSETTLED FOR MOST OF THE WEEK WITH
TEMPERATURES RUNNING CLOSE TO SEASONAL NORMS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1041 AM MST SAT DEC 20 2014

MID LEVEL CLOUDS WILL REMAIN OVER THE AREA FOR MUCH OF THE DAY
WITH SOME LIGHT SNOW SHOWERS ALSO POSSIBLE. ANY THAT FORM SHOULD
BE SHORT-LIVED AND NOT DROP VIS OR CIGS TOO LOW FOR AVN CONCERNS.
OFF TO THE WEST...THE NEXT WAVE IS TAKING AIM AT OUR CWA AND
EXPECT IT TO ENTER OUR CWA IN THE NEXT FEW HOURS AND MOVE ACROSS
EASTERN UT/WRN CO THIS EVENING INTO TONIGHT. EXPECT CLOUDS TO
DROP A LITTLE BIT MORE....NEAR 040 TO 060K FT FROM 21Z ONWARDS.
THE CHANCE DOES EXIST FOR SOME SNOW SHOWERS BUT CONFIDENCE NOT
HIGH ENOUGH FOR TAFS EXCEPT KASE AFTER 06Z. REMAINING SITES WILL
LIKELY SEE VCSH THOUGH THE CHANCE DOES EXIST FOR SOME FLAKES AT
AIRPORTS. THE MAIN AVN CONCERN WILL START MOVING IN JUST AFTER 18Z
TOMORROW WITH THE NEXT STORM SYSTEM.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...WINTER WEATHER ADVISORY FROM 6 PM SUNDAY TO 6 PM MST MONDAY FOR
     COZ017>019.

     WINTER STORM WARNING FROM 6 AM SUNDAY TO MIDNIGHT MST MONDAY
     NIGHT FOR COZ010-012.

     WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR COZ002-008-014.

     WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO MIDNIGHT MST
     MONDAY NIGHT FOR COZ004-013.

     WINTER WEATHER ADVISORY FROM NOON SUNDAY TO 6 PM MST MONDAY FOR
     COZ003.

     WINTER STORM WARNING FROM NOON SUNDAY TO 6 PM MST MONDAY FOR
     COZ009.

     WINTER STORM WARNING FROM 6 AM SUNDAY TO 6 PM MST MONDAY FOR
     COZ005.

UT...NONE.
&&

$$

SHORT TERM...JAM
LONG TERM...JDC
AVIATION...TGR





000
FXUS65 KGJT 201746
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1046 AM MST SAT DEC 20 2014

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 410 AM MST SAT DEC 20 2014

HAND ANALYSIS TONIGHT INDICATES RIDGE STILL OVER THE REGION...BUT
THE RIDGE IS BREAKING DOWN THIS MORNING AHEAD OF THE NEXT
SUBSTANTIAL WEATHER SYSTEM. A FEW RETURNS ARE SHOWING UP ON RADAR
THIS MORNING...BUT UNLIKE YESTERDAY MORNING...THIS IS JUST LIKELY
MID LEVEL CLOUDS SHOWING UP MIXED IN WITH A FEW ELEVATED SHOWERS.
THE SHORT TERM MODELS (RAP AND HRRR) INDICATE SOME SCATTERED
SHOWERS DEVELOPING ON THE ROAN/TAVAPUTS THIS MORNING AND ACROSS
NORTHWEST COLORADO SO ADDED THOSE INTO THE POP GRIDS
TODAY...ESPECIALLY CONSIDERING BAGGS WY AND HEBER CITY UT ARE
RECEIVING LIGHT SNOW THIS MORNING. ATMOSPHERIC MOISTURE IS
DEFINITELY AVAILABLE WITH SPEC HUMIDITIES BACK UP TO 3G/KG THIS
MORNING...THOUGH MOISTURE IS ELEVATED WITH DWPT DEPRESSIONS LARGER
THIS MORNING THAN THE LAST FEW DAYS WITHOUT THE LOW/SFC LEVEL
MOISTURE.

70KT UPPER LEVEL JET SUPPORT MAKES ITS WAY INTO THE FORECAST AREA
FROM THE WEST WHICH WILL SLOWLY INCREASE WINDS AT HIGHER TERRAIN
ACROSS ELEVATED PARTS OF NE UT AND NW CO AND AID IN UPPER LEVEL
DIVERGENCE TODAY. EVEN STRONGER (100KT) JET STREAK BLAZES THROUGH
ON SUNDAY AS THE FIRST HEAVIER PRECIPITATION IS EXPECTED TO BEGIN
IN NORTHWEST AND NORTH CENTRAL COLORADO. LOW LEVEL MOISTURE WILL
INCREASE ACROSS NE UT AND NW CO TODAY...THEN ACROSS THE REST OF
THE FORECAST AREA ON SUNDAY IN WARM AIR ADVECTION. NOT EXPECTING
HIGH SNOW AMTS ACROSS THE EASTERN UINTAS AS WE ARE EXPECTING THIS
AREA TO BE SHADOWED DUE TO THE STRONG UPPER LEVEL WESTERLY
WINDS...THOUGH WILL NEED TO CONSIDER THE NEED FOR AN ADVISORY IF
CONDITIONS CHANGE.

THIS UPCOMING WINTER STORM WILL REALLY TAKE HOLD ON SUNDAY WHICH
WILL BE QUITE NOTICEABLE WITH NORTHWEST WINDS RAPIDLY INCREASING
SUNDAY MORNING OVER NE UT AND NW CO. SNOW ACROSS THE NORTH CENTRAL
AND CENTRAL MOUNTAINS OF WESTERN CO WILL INCREASE IN COVERAGE AND
INTENSITY ON SUNDAY AS WELL. BLOWING SNOW WILL DEFINITELY BECOME
AN ISSUE AT HIGHER TERRAIN AND DO EXPECT IT TO BE DIFFICULT TO
MEASURE SNOWFALL AMOUNTS FOR THIS STORM. SEE LONG TERM SECTION FOR
MORE DETAILS ON THIS STORM DEVELOPMENT.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 410 AM MST SAT DEC 20 2014

...MAJOR WINTER STORM WILL CONTINUE TO BRING HEAVY SNOW AND
BLOWING SNOW TO THE MOUNTAINS OF WESTERN COLORADO THROUGH
MONDAY...

STRONG UPPER LEVEL JET WILL BE MOVING OVERHEAD SUNDAY NIGHT AND
MONDAY WITH H3 SPEEDS CLOCKING IN NEAR 140 KTS BY LATE MONDAY
AFTERNOON. THE FORECAST AREA WILL BE IN PRIME POSITION FOR
ENHANCED JET DYNAMICS FOR AT LEAST 18 HOURS BEGINNING SUNDAY
NIGHT AND THROUGH THE DAY ON MONDAY. PLENTY OF PACIFIC MOISTURE
WILL BE AVAILABLE AND WITH TEMPS IN FAVORABLE DENDRITIC GROWTH
ZONE OVERNIGHT SUNDAY THROUGH MONDAY...EXPECT HEAVY SNOWFALL WILL
NOT BE A PROBLEM WITH HIGH CONFIDENCE THAT MOST OF THE MOUNTAINS
IN WESTERN COLORADO WILL BE MEASURING SNOWFALL WITH A YARD STICK
BY THE TIME MONDAY EVENING ROLLS AROUND. WILL STILL BE CONTENDING
WITH A SHOT OF WAA ON SUNDAY WHICH MAY SLOW THINGS DOWN A
BIT...BUT COOLING ARRIVES SUNDAY NIGHT INTO THE DAY ON MONDAY AS
THE JET SHIFTS OVERHEAD.

A FEW AREAS MAY EXPERIENCE NEAR BLIZZARD CONDITIONS WITH GUSTS
EXCEEDING 45 MPH...ESPECIALLY ABOVE TIMBERLINE ACROSS THE PARK AND
GORE RANGES AND POSSIBLY AS FAR SOUTH AS VAIL PASS ON MONDAY.
SHARP GRADIENT TO THE HEAVY SNOW IS EXPECTED AND THE EXACT
POSITIONING OF THE JET WILL PLAY A BIG ROLE IN THE EVENTUAL
OUTCOME. OROGRAPHIC WIND FIELDS SHOWING SOME BEND TO A MORE
NORTHERLY COMPONENT ON MONDAY WHICH WOULD SLOW SNOW POTENTIAL
ACROSS THE NORTHERN MOUNTAINS...BUT SHIFT THINGS INTO THE CENTRAL
MOUNTAINS NEAR ASPEN...THUS THE EXPANSION OF HIGHLIGHTS TO
INCLUDE THE GRAND MESA AND ZONE 12 NEAR CRESTED BUTTE AND GOTHIC.

WITH CONFIDENCE HIGH AND HOLIDAY TRAVEL UNDERWAY...HAVE ISSUED
WARNINGS AND ADVISORIES FOR ALL OF THE MOUNTAINS IN WESTERN
COLORADO. HIGHER VALLEYS WILL ALSO BE GETTING INTO THE ACTION
SUNDAY AFTERNOON THROUGH MONDAY AND WILL EXPAND THE WATCH TO
INCLUDE CRAIG AND GUNNISON WHERE WE ARE GENERATING 6 PLUS INCHES
OF SNOW THROUGH THAT 24 HOUR PERIOD.

ADDITIONAL CONCERNS ACROSS NORTHEAST UTAH AND EXTREME NORTHWEST
COLORADO WILL BE WINDS WITH H7 SPEEDS CLOCKING IN AROUND 50-60KTS
BY LATE MONDAY AFTERNOON. FOOTPRINT OF THE STRONGEST WINDS ARE
CONFINED TO A NARROW REGION OF OUR FORECAST AREA...GENERALLY NORTH
OF THE EASTERN UINTA MOUNTAINS IN NORTHEAST UTAH INTO EXTREME
NORTHWEST COLORADO NORTH OF DINOSAUR NATIONAL MONUMENT. LATER
SHIFTS WILL NEED TO EVALUATE POTENTIAL FOR WIND OR WINTER
HIGHLIGHTS...BUT CONFIDENCE IN THE SNOW THROUGH THIS AREA WAS NOT
AS HIGH AND WE STILL HAVE TIME DO WORK OUT THE FINER DETAILS IN
THIS AREA.

THIS STORM WILL EXIT LATE MONDAY NIGHT AND TUESDAY WITH TRANSITORY
RIDGE SLIDING THROUGH TUESDAY NIGHT AND WEDNESDAY. THE POTENTIAL
STORM ON CHRISTMAS DAY IS ON SHAKEY GROUND AS THE LATEST GFS RUN
HAS BACKED OFF THE INTENSITY AND CONTINUES TO SHIFT BEST ENERGY
NORTH OF OUR FORECAST AREA. THE ECMWF HAS ALSO BACKED OFF
INTENSITY A BIT AND HAS STARTED TO SHIFT NORTH AS WELL. AFTER
COORDINATION WITH SURROUNDING OFFICES...WILL MAINTAIN HIGHER POPS
FOR NOW WITH FORECAST DIRECTED MORE TOWARD THE WETTER AND DEEPER
EC SOLUTION...WHICH HAS BEEN THE MOST CONSISTENT MODEL OVER THE
PAST FEW DAYS IN REGARDS TO THIS SYSTEM. BOTTOM LINE IS THAT
CONDITIONS WILL REMAIN UNSETTLED FOR MOST OF THE WEEK WITH
TEMPERATURES RUNNING CLOSE TO SEASONAL NORMS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1041 AM MST SAT DEC 20 2014

MID LEVEL CLOUDS WILL REMAIN OVER THE AREA FOR MUCH OF THE DAY
WITH SOME LIGHT SNOW SHOWERS ALSO POSSIBLE. ANY THAT FORM SHOULD
BE SHORT-LIVED AND NOT DROP VIS OR CIGS TOO LOW FOR AVN CONCERNS.
OFF TO THE WEST...THE NEXT WAVE IS TAKING AIM AT OUR CWA AND
EXPECT IT TO ENTER OUR CWA IN THE NEXT FEW HOURS AND MOVE ACROSS
EASTERN UT/WRN CO THIS EVENING INTO TONIGHT. EXPECT CLOUDS TO
DROP A LITTLE BIT MORE....NEAR 040 TO 060K FT FROM 21Z ONWARDS.
THE CHANCE DOES EXIST FOR SOME SNOW SHOWERS BUT CONFIDENCE NOT
HIGH ENOUGH FOR TAFS EXCEPT KASE AFTER 06Z. REMAINING SITES WILL
LIKELY SEE VCSH THOUGH THE CHANCE DOES EXIST FOR SOME FLAKES AT
AIRPORTS. THE MAIN AVN CONCERN WILL START MOVING IN JUST AFTER 18Z
TOMORROW WITH THE NEXT STORM SYSTEM.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...WINTER WEATHER ADVISORY FROM 6 PM SUNDAY TO 6 PM MST MONDAY FOR
     COZ017>019.

     WINTER STORM WARNING FROM 6 AM SUNDAY TO MIDNIGHT MST MONDAY
     NIGHT FOR COZ010-012.

     WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR COZ002-008-014.

     WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO MIDNIGHT MST
     MONDAY NIGHT FOR COZ004-013.

     WINTER WEATHER ADVISORY FROM NOON SUNDAY TO 6 PM MST MONDAY FOR
     COZ003.

     WINTER STORM WARNING FROM NOON SUNDAY TO 6 PM MST MONDAY FOR
     COZ009.

     WINTER STORM WARNING FROM 6 AM SUNDAY TO 6 PM MST MONDAY FOR
     COZ005.

UT...NONE.
&&

$$

SHORT TERM...JAM
LONG TERM...JDC
AVIATION...TGR




000
FXUS65 KGJT 201119
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
419 AM MST SAT DEC 20 2014

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 410 AM MST SAT DEC 20 2014

HAND ANALYSIS TONIGHT INDICATES RIDGE STILL OVER THE REGION...BUT
THE RIDGE IS BREAKING DOWN THIS MORNING AHEAD OF THE NEXT
SUBSTANTIAL WEATHER SYSTEM. A FEW RETURNS ARE SHOWING UP ON RADAR
THIS MORNING...BUT UNLIKE YESTERDAY MORNING...THIS IS JUST LIKELY
MID LEVEL CLOUDS SHOWING UP MIXED IN WITH A FEW ELEVATED SHOWERS.
THE SHORT TERM MODELS (RAP AND HRRR) INDICATE SOME SCATTERED
SHOWERS DEVELOPING ON THE ROAN/TAVAPUTS THIS MORNING AND ACROSS
NORTHWEST COLORADO SO ADDED THOSE INTO THE POP GRIDS
TODAY...ESPECIALLY CONSIDERING BAGGS WY AND HEBER CITY UT ARE
RECEIVING LIGHT SNOW THIS MORNING. ATMOSPHERIC MOISTURE IS
DEFINITELY AVAILABLE WITH SPEC HUMIDITIES BACK UP TO 3G/KG THIS
MORNING...THOUGH MOISTURE IS ELEVATED WITH DWPT DEPRESSIONS LARGER
THIS MORNING THAN THE LAST FEW DAYS WITHOUT THE LOW/SFC LEVEL
MOISTURE.

70KT UPPER LEVEL JET SUPPORT MAKES ITS WAY INTO THE FORECAST AREA
FROM THE WEST WHICH WILL SLOWLY INCREASE WINDS AT HIGHER TERRAIN
ACROSS ELEVATED PARTS OF NE UT AND NW CO AND AID IN UPPER LEVEL
DIVERGENCE TODAY. EVEN STRONGER (100KT) JET STREAK BLAZES THROUGH
ON SUNDAY AS THE FIRST HEAVIER PRECIPITATION IS EXPECTED TO BEGIN
IN NORTHWEST AND NORTH CENTRAL COLORADO. LOW LEVEL MOISTURE WILL
INCREASE ACROSS NE UT AND NW CO TODAY...THEN ACROSS THE REST OF
THE FORECAST AREA ON SUNDAY IN WARM AIR ADVECTION. NOT EXPECTING
HIGH SNOW AMTS ACROSS THE EASTERN UINTAS AS WE ARE EXPECTING THIS
AREA TO BE SHADOWED DUE TO THE STRONG UPPER LEVEL WESTERLY
WINDS...THOUGH WILL NEED TO CONSIDER THE NEED FOR AN ADVISORY IF
CONDITIONS CHANGE.

THIS UPCOMING WINTER STORM WILL REALLY TAKE HOLD ON SUNDAY WHICH
WILL BE QUITE NOTICEABLE WITH NORTHWEST WINDS RAPIDLY INCREASING
SUNDAY MORNING OVER NE UT AND NW CO. SNOW ACROSS THE NORTH CENTRAL
AND CENTRAL MOUNTAINS OF WESTERN CO WILL INCREASE IN COVERAGE AND
INTENSITY ON SUNDAY AS WELL. BLOWING SNOW WILL DEFINITELY BECOME
AN ISSUE AT HIGHER TERRAIN AND DO EXPECT IT TO BE DIFFICULT TO
MEASURE SNOWFALL AMOUNTS FOR THIS STORM. SEE LONG TERM SECTION FOR
MORE DETAILS ON THIS STORM DEVELOPMENT.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 410 AM MST SAT DEC 20 2014

...MAJOR WINTER STORM WILL CONTINUE TO BRING HEAVY SNOW AND
BLOWING SNOW TO THE MOUNTAINS OF WESTERN COLORADO THROUGH
MONDAY...

STRONG UPPER LEVEL JET WILL BE MOVING OVERHEAD SUNDAY NIGHT AND
MONDAY WITH H3 SPEEDS CLOCKING IN NEAR 140 KTS BY LATE MONDAY
AFTERNOON. THE FORECAST AREA WILL BE IN PRIME POSITION FOR
ENHANCED JET DYNAMICS FOR AT LEAST 18 HOURS BEGINNING SUNDAY
NIGHT AND THROUGH THE DAY ON MONDAY. PLENTY OF PACIFIC MOISTURE
WILL BE AVAILABLE AND WITH TEMPS IN FAVORABLE DENDRITIC GROWTH
ZONE OVERNIGHT SUNDAY THROUGH MONDAY...EXPECT HEAVY SNOWFALL WILL
NOT BE A PROBLEM WITH HIGH CONFIDENCE THAT MOST OF THE MOUNTAINS
IN WESTERN COLORADO WILL BE MEASURING SNOWFALL WITH A YARD STICK
BY THE TIME MONDAY EVENING ROLLS AROUND. WILL STILL BE CONTENDING
WITH A SHOT OF WAA ON SUNDAY WHICH MAY SLOW THINGS DOWN A
BIT...BUT COOLING ARRIVES SUNDAY NIGHT INTO THE DAY ON MONDAY AS
THE JET SHIFTS OVERHEAD.

A FEW AREAS MAY EXPERIENCE NEAR BLIZZARD CONDITIONS WITH GUSTS
EXCEEDING 45 MPH...ESPECIALLY ABOVE TIMBERLINE ACROSS THE PARK AND
GORE RANGES AND POSSIBLY AS FAR SOUTH AS VAIL PASS ON MONDAY.
SHARP GRADIENT TO THE HEAVY SNOW IS EXPECTED AND THE EXACT
POSITIONING OF THE JET WILL PLAY A BIG ROLE IN THE EVENTUAL
OUTCOME. OROGRAPHIC WIND FIELDS SHOWING SOME BEND TO A MORE
NORTHERLY COMPONENT ON MONDAY WHICH WOULD SLOW SNOW POTENTIAL
ACROSS THE NORTHERN MOUNTAINS...BUT SHIFT THINGS INTO THE CENTRAL
MOUNTAINS NEAR ASPEN...THUS THE EXPANSION OF HIGHLIGHTS TO
INCLUDE THE GRAND MESA AND ZONE 12 NEAR CRESTED BUTTE AND GOTHIC.

WITH CONFIDENCE HIGH AND HOLIDAY TRAVEL UNDERWAY...HAVE ISSUED
WARNINGS AND ADVISORIES FOR ALL OF THE MOUNTAINS IN WESTERN
COLORADO. HIGHER VALLEYS WILL ALSO BE GETTING INTO THE ACTION
SUNDAY AFTERNOON THROUGH MONDAY AND WILL EXPAND THE WATCH TO
INCLUDE CRAIG AND GUNNISON WHERE WE ARE GENERATING 6 PLUS INCHES
OF SNOW THROUGH THAT 24 HOUR PERIOD.

ADDITIONAL CONCERNS ACROSS NORTHEAST UTAH AND EXTREME NORTHWEST
COLORADO WILL BE WINDS WITH H7 SPEEDS CLOCKING IN AROUND 50-60KTS
BY LATE MONDAY AFTERNOON. FOOTPRINT OF THE STRONGEST WINDS ARE
CONFINED TO A NARROW REGION OF OUR FORECAST AREA...GENERALLY NORTH
OF THE EASTERN UINTA MOUNTAINS IN NORTHEAST UTAH INTO EXTREME
NORTHWEST COLORADO NORTH OF DINOSAUR NATIONAL MONUMENT. LATER
SHIFTS WILL NEED TO EVALUATE POTENTIAL FOR WIND OR WINTER
HIGHLIGHTS...BUT CONFIDENCE IN THE SNOW THROUGH THIS AREA WAS NOT
AS HIGH AND WE STILL HAVE TIME DO WORK OUT THE FINER DETAILS IN
THIS AREA.

THIS STORM WILL EXIT LATE MONDAY NIGHT AND TUESDAY WITH TRANSITORY
RIDGE SLIDING THROUGH TUESDAY NIGHT AND WEDNESDAY. THE POTENTIAL
STORM ON CHRISTMAS DAY IS ON SHAKEY GROUND AS THE LATEST GFS RUN
HAS BACKED OFF THE INTENSITY AND CONTINUES TO SHIFT BEST ENERGY
NORTH OF OUR FORECAST AREA. THE ECMWF HAS ALSO BACKED OFF
INTENSITY A BIT AND HAS STARTED TO SHIFT NORTH AS WELL. AFTER
COORDINATION WITH SURROUNDING OFFICES...WILL MAINTAIN HIGHER POPS
FOR NOW WITH FORECAST DIRECTED MORE TOWARD THE WETTER AND DEEPER
EC SOLUTION...WHICH HAS BEEN THE MOST CONSISTENT MODEL OVER THE
PAST FEW DAYS IN REGARDS TO THIS SYSTEM. BOTTOM LINE IS THAT
CONDITIONS WILL REMAIN UNSETTLED FOR MOST OF THE WEEK WITH
TEMPERATURES RUNNING CLOSE TO SEASONAL NORMS.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 410 AM MST SAT DEC 20 2014

VFR CONDITIONS EXPECTED AT ALL SITES THROUGH 02Z THIS EVENING WITH
MID AND HIGH LEVEL CLOUDS STREAMING THROUGH THE REGION AHEAD OF A
DEEPER SURGE OF MOISTURE THAT WILL BE MOVING IN TONIGHT. AFTER
02Z...SCATTERED SHOWERS WILL BE DEVELOPING OVER THE HIGHER
MOUNTAINS ALONG AND NORTH OF INTERSTATE 70 WITH CIGS GRADUALLY
DROPPING THROUGHOUT THE NIGHT.

BY EARLY SUNDAY MORNING...WIDESPREAD MVFR CIGS WITH AREAS OF IFR
CIGS CAN BE EXPECTED ACROSS NORTHEAST UTAH AND MUCH OF NORTHWEST
COLORADO AND INTO THE CENTRAL MOUNTAINS IN WESTERN COLORADO.
KASE...KEGE...KHDN AND KSBS WILL ALL BE IMPACTED BY THE DROPPING
CIGS BY EARLY SUNDAY MORNING.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY FROM 6 PM SUNDAY TO 6 PM MST MONDAY FOR
     COZ017>019.

     WINTER STORM WARNING FROM 6 AM SUNDAY TO MIDNIGHT MST MONDAY
     NIGHT FOR COZ010-012.

     WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR COZ002-008-014.

     WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO MIDNIGHT MST
     MONDAY NIGHT FOR COZ004-013.

     WINTER WEATHER ADVISORY FROM NOON SUNDAY TO 6 PM MST MONDAY FOR
     COZ003.

     WINTER STORM WARNING FROM NOON SUNDAY TO 6 PM MST MONDAY FOR
     COZ009.

     WINTER STORM WARNING FROM 6 AM SUNDAY TO 6 PM MST MONDAY FOR
     COZ005.

UT...NONE.
&&

$$

SHORT TERM...JAM
LONG TERM...JDC
AVIATION...JDC




000
FXUS65 KGJT 201119
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
419 AM MST SAT DEC 20 2014

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 410 AM MST SAT DEC 20 2014

HAND ANALYSIS TONIGHT INDICATES RIDGE STILL OVER THE REGION...BUT
THE RIDGE IS BREAKING DOWN THIS MORNING AHEAD OF THE NEXT
SUBSTANTIAL WEATHER SYSTEM. A FEW RETURNS ARE SHOWING UP ON RADAR
THIS MORNING...BUT UNLIKE YESTERDAY MORNING...THIS IS JUST LIKELY
MID LEVEL CLOUDS SHOWING UP MIXED IN WITH A FEW ELEVATED SHOWERS.
THE SHORT TERM MODELS (RAP AND HRRR) INDICATE SOME SCATTERED
SHOWERS DEVELOPING ON THE ROAN/TAVAPUTS THIS MORNING AND ACROSS
NORTHWEST COLORADO SO ADDED THOSE INTO THE POP GRIDS
TODAY...ESPECIALLY CONSIDERING BAGGS WY AND HEBER CITY UT ARE
RECEIVING LIGHT SNOW THIS MORNING. ATMOSPHERIC MOISTURE IS
DEFINITELY AVAILABLE WITH SPEC HUMIDITIES BACK UP TO 3G/KG THIS
MORNING...THOUGH MOISTURE IS ELEVATED WITH DWPT DEPRESSIONS LARGER
THIS MORNING THAN THE LAST FEW DAYS WITHOUT THE LOW/SFC LEVEL
MOISTURE.

70KT UPPER LEVEL JET SUPPORT MAKES ITS WAY INTO THE FORECAST AREA
FROM THE WEST WHICH WILL SLOWLY INCREASE WINDS AT HIGHER TERRAIN
ACROSS ELEVATED PARTS OF NE UT AND NW CO AND AID IN UPPER LEVEL
DIVERGENCE TODAY. EVEN STRONGER (100KT) JET STREAK BLAZES THROUGH
ON SUNDAY AS THE FIRST HEAVIER PRECIPITATION IS EXPECTED TO BEGIN
IN NORTHWEST AND NORTH CENTRAL COLORADO. LOW LEVEL MOISTURE WILL
INCREASE ACROSS NE UT AND NW CO TODAY...THEN ACROSS THE REST OF
THE FORECAST AREA ON SUNDAY IN WARM AIR ADVECTION. NOT EXPECTING
HIGH SNOW AMTS ACROSS THE EASTERN UINTAS AS WE ARE EXPECTING THIS
AREA TO BE SHADOWED DUE TO THE STRONG UPPER LEVEL WESTERLY
WINDS...THOUGH WILL NEED TO CONSIDER THE NEED FOR AN ADVISORY IF
CONDITIONS CHANGE.

THIS UPCOMING WINTER STORM WILL REALLY TAKE HOLD ON SUNDAY WHICH
WILL BE QUITE NOTICEABLE WITH NORTHWEST WINDS RAPIDLY INCREASING
SUNDAY MORNING OVER NE UT AND NW CO. SNOW ACROSS THE NORTH CENTRAL
AND CENTRAL MOUNTAINS OF WESTERN CO WILL INCREASE IN COVERAGE AND
INTENSITY ON SUNDAY AS WELL. BLOWING SNOW WILL DEFINITELY BECOME
AN ISSUE AT HIGHER TERRAIN AND DO EXPECT IT TO BE DIFFICULT TO
MEASURE SNOWFALL AMOUNTS FOR THIS STORM. SEE LONG TERM SECTION FOR
MORE DETAILS ON THIS STORM DEVELOPMENT.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 410 AM MST SAT DEC 20 2014

...MAJOR WINTER STORM WILL CONTINUE TO BRING HEAVY SNOW AND
BLOWING SNOW TO THE MOUNTAINS OF WESTERN COLORADO THROUGH
MONDAY...

STRONG UPPER LEVEL JET WILL BE MOVING OVERHEAD SUNDAY NIGHT AND
MONDAY WITH H3 SPEEDS CLOCKING IN NEAR 140 KTS BY LATE MONDAY
AFTERNOON. THE FORECAST AREA WILL BE IN PRIME POSITION FOR
ENHANCED JET DYNAMICS FOR AT LEAST 18 HOURS BEGINNING SUNDAY
NIGHT AND THROUGH THE DAY ON MONDAY. PLENTY OF PACIFIC MOISTURE
WILL BE AVAILABLE AND WITH TEMPS IN FAVORABLE DENDRITIC GROWTH
ZONE OVERNIGHT SUNDAY THROUGH MONDAY...EXPECT HEAVY SNOWFALL WILL
NOT BE A PROBLEM WITH HIGH CONFIDENCE THAT MOST OF THE MOUNTAINS
IN WESTERN COLORADO WILL BE MEASURING SNOWFALL WITH A YARD STICK
BY THE TIME MONDAY EVENING ROLLS AROUND. WILL STILL BE CONTENDING
WITH A SHOT OF WAA ON SUNDAY WHICH MAY SLOW THINGS DOWN A
BIT...BUT COOLING ARRIVES SUNDAY NIGHT INTO THE DAY ON MONDAY AS
THE JET SHIFTS OVERHEAD.

A FEW AREAS MAY EXPERIENCE NEAR BLIZZARD CONDITIONS WITH GUSTS
EXCEEDING 45 MPH...ESPECIALLY ABOVE TIMBERLINE ACROSS THE PARK AND
GORE RANGES AND POSSIBLY AS FAR SOUTH AS VAIL PASS ON MONDAY.
SHARP GRADIENT TO THE HEAVY SNOW IS EXPECTED AND THE EXACT
POSITIONING OF THE JET WILL PLAY A BIG ROLE IN THE EVENTUAL
OUTCOME. OROGRAPHIC WIND FIELDS SHOWING SOME BEND TO A MORE
NORTHERLY COMPONENT ON MONDAY WHICH WOULD SLOW SNOW POTENTIAL
ACROSS THE NORTHERN MOUNTAINS...BUT SHIFT THINGS INTO THE CENTRAL
MOUNTAINS NEAR ASPEN...THUS THE EXPANSION OF HIGHLIGHTS TO
INCLUDE THE GRAND MESA AND ZONE 12 NEAR CRESTED BUTTE AND GOTHIC.

WITH CONFIDENCE HIGH AND HOLIDAY TRAVEL UNDERWAY...HAVE ISSUED
WARNINGS AND ADVISORIES FOR ALL OF THE MOUNTAINS IN WESTERN
COLORADO. HIGHER VALLEYS WILL ALSO BE GETTING INTO THE ACTION
SUNDAY AFTERNOON THROUGH MONDAY AND WILL EXPAND THE WATCH TO
INCLUDE CRAIG AND GUNNISON WHERE WE ARE GENERATING 6 PLUS INCHES
OF SNOW THROUGH THAT 24 HOUR PERIOD.

ADDITIONAL CONCERNS ACROSS NORTHEAST UTAH AND EXTREME NORTHWEST
COLORADO WILL BE WINDS WITH H7 SPEEDS CLOCKING IN AROUND 50-60KTS
BY LATE MONDAY AFTERNOON. FOOTPRINT OF THE STRONGEST WINDS ARE
CONFINED TO A NARROW REGION OF OUR FORECAST AREA...GENERALLY NORTH
OF THE EASTERN UINTA MOUNTAINS IN NORTHEAST UTAH INTO EXTREME
NORTHWEST COLORADO NORTH OF DINOSAUR NATIONAL MONUMENT. LATER
SHIFTS WILL NEED TO EVALUATE POTENTIAL FOR WIND OR WINTER
HIGHLIGHTS...BUT CONFIDENCE IN THE SNOW THROUGH THIS AREA WAS NOT
AS HIGH AND WE STILL HAVE TIME DO WORK OUT THE FINER DETAILS IN
THIS AREA.

THIS STORM WILL EXIT LATE MONDAY NIGHT AND TUESDAY WITH TRANSITORY
RIDGE SLIDING THROUGH TUESDAY NIGHT AND WEDNESDAY. THE POTENTIAL
STORM ON CHRISTMAS DAY IS ON SHAKEY GROUND AS THE LATEST GFS RUN
HAS BACKED OFF THE INTENSITY AND CONTINUES TO SHIFT BEST ENERGY
NORTH OF OUR FORECAST AREA. THE ECMWF HAS ALSO BACKED OFF
INTENSITY A BIT AND HAS STARTED TO SHIFT NORTH AS WELL. AFTER
COORDINATION WITH SURROUNDING OFFICES...WILL MAINTAIN HIGHER POPS
FOR NOW WITH FORECAST DIRECTED MORE TOWARD THE WETTER AND DEEPER
EC SOLUTION...WHICH HAS BEEN THE MOST CONSISTENT MODEL OVER THE
PAST FEW DAYS IN REGARDS TO THIS SYSTEM. BOTTOM LINE IS THAT
CONDITIONS WILL REMAIN UNSETTLED FOR MOST OF THE WEEK WITH
TEMPERATURES RUNNING CLOSE TO SEASONAL NORMS.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 410 AM MST SAT DEC 20 2014

VFR CONDITIONS EXPECTED AT ALL SITES THROUGH 02Z THIS EVENING WITH
MID AND HIGH LEVEL CLOUDS STREAMING THROUGH THE REGION AHEAD OF A
DEEPER SURGE OF MOISTURE THAT WILL BE MOVING IN TONIGHT. AFTER
02Z...SCATTERED SHOWERS WILL BE DEVELOPING OVER THE HIGHER
MOUNTAINS ALONG AND NORTH OF INTERSTATE 70 WITH CIGS GRADUALLY
DROPPING THROUGHOUT THE NIGHT.

BY EARLY SUNDAY MORNING...WIDESPREAD MVFR CIGS WITH AREAS OF IFR
CIGS CAN BE EXPECTED ACROSS NORTHEAST UTAH AND MUCH OF NORTHWEST
COLORADO AND INTO THE CENTRAL MOUNTAINS IN WESTERN COLORADO.
KASE...KEGE...KHDN AND KSBS WILL ALL BE IMPACTED BY THE DROPPING
CIGS BY EARLY SUNDAY MORNING.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY FROM 6 PM SUNDAY TO 6 PM MST MONDAY FOR
     COZ017>019.

     WINTER STORM WARNING FROM 6 AM SUNDAY TO MIDNIGHT MST MONDAY
     NIGHT FOR COZ010-012.

     WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR COZ002-008-014.

     WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO MIDNIGHT MST
     MONDAY NIGHT FOR COZ004-013.

     WINTER WEATHER ADVISORY FROM NOON SUNDAY TO 6 PM MST MONDAY FOR
     COZ003.

     WINTER STORM WARNING FROM NOON SUNDAY TO 6 PM MST MONDAY FOR
     COZ009.

     WINTER STORM WARNING FROM 6 AM SUNDAY TO 6 PM MST MONDAY FOR
     COZ005.

UT...NONE.
&&

$$

SHORT TERM...JAM
LONG TERM...JDC
AVIATION...JDC





000
FXUS65 KGJT 200555
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1055 PM MST FRI DEC 19 2014

.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)
ISSUED AT 229 PM MST FRI DEC 19 2014

A WEAK DISTURBANCE AND LOW-LEVEL INSTABILITY GENERATED AREAS OF
LIGHT SNOW THIS MORNING ACROSS WEST-CENTRAL AND NORTHWEST COLORADO.
WE RECEIVED 0.5 INCH OF SNOW HERE AT THE GJT WEATHER OFFICE...THE
FIRST MEASURABLE SNOW AT THE OFFICE SO FAR THIS SEASON.

MOST OF THE AREA WILL REMAIN DRY TONIGHT THROUGH SATURDAY AFTERNOON.
WARM ADVECTIVE HIGH CLOUDS WERE MOVING IN THIS AFTERNOON AHEAD OF A
WEAK WAVE THAT WILL CROSS TONIGHT. ANOTHER PACIFIC TROUGH AND ITS
ASSOCIATED SURFACE COLD FRONT WAS PUSHING ACROSS THROUGH THE PAC NW
AND WESTERN GREAT BASIN THIS AFTERNOON. Q-G DIAGNOSTICS SHOWED THIS
WAVE WEAKENING CONSIDERABLY BY THE TIME IT CROSSES WRN CO SAT
MORNING FOR SCATTERED LIGHT SNOW ACROSS THE NRN MOUNTAINS SAT. MAY
SEE A FEW FLAKES AROUND MEEKER...CRAIG TO STEAMBOAT SPGS AS THE
WESTERLY FLOW ENCOUNTERS THE HIGHER TERRAIN. THESE WAVES WILL NOT BE
STRONG ENOUGH TO FLUSH OUT THE EASTERN UINTA BASIN WHERE LOW CLOUDS
WILL HANG ON.

A STRONG AND MOIST PACIFIC JET PUNCHES INTO WA/OR WITH 310K AND 315K
ISENTROPIC FIELDS SHOWING THE INITIAL MOISTURE PUSH REACHING NE
UT/NW CO SAT NIGHT IN WARM ADVECTION/ISENTROPIC UPGLIDE. MADE ONLY
MINOR CHANGES TO THE CURRENT POP GRIDS WHICH HAVE SNOW BECOMING
WIDESPREAD ACROSS THE NRN MOUNTAINS AFTER MIDNIGHT SAT NIGHT AND
SPREADING INTO THE CENTRAL MTNS BY 12Z SUNDAY. LIKELY TO SEE SOME
LIGHT SNOW IN THE CRAIG/MEEKER/STEAMBOAT AREAS BY 12Z SUNDAY AS
WELL. IN CONTRAST...ONLY A CHANCE OF LIGHT SNOW FOR THE EASTERN
UINTA MTNS SAT NIGHT IN THE SHADOW OF THE HIGHER MTNS TO THEIR
WEST.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 229 PM MST FRI DEC 19 2014

TWO STORMS ARE STILL TIMED TO IMPACT THE REGION SUNDAY THOUGH
MONDAY AND THEN AGAIN CHRISTMAS DAY. DETAILS FOR THE WEEKEND
STORM ARE BETTER RESOLVED FAVORING THE NORTH...ESPECIALLY THE NW
CO MTNS...WITH SIGNIFICANT SNOWFALL. CURRENT HIGHLIGHTS ARE IN
GOOD SHAPE THOUGH SURROUNDING MTN ZONES LOOK LIKE THEY MAY REACH
ADVISORY SNOW AMOUNTS.

SUNDAY IN MILD NW FLOW...MOISTURE DEEPENS OVER THE FORECAST AREA.
700MB SPECIFIC HUMIDITIES CLIMB TO 4 G/KG OVER THE NORTH. SNOW
LEVELS WILL BE A CHALLENGE EXPECTED TO RISE TO AROUND 7KFT IN THE
AFTERNOON. OROGRAPHICS IS THE MAIN FORCING MECHANISM. DENDRITIC
CRYSTAL GROWTH REGION IS NEAR SATURATION BUT IS HIGH AT AROUND
15-17KFT MSL. SO HAVE KEPT THE HIGH POPS FOR SUNDAY BUT LOWERED
SNOW ACCUMULATIONS SOMEWHAT.

SUNDAY NIGHT-MONDAY JET SUPPORT NOSES IN FROM THE NW WITH COLD
ADVECTION LOWERING 700MB TEMPS FROM -6 TO -10. DENDRITIC LAYER
LOWERS TO AROUND 11KFT MSL. THE GFS IS PRODUCING OVER A FOOT OF
SNOW OVER THE PARK GORE FLAT TOP RANGES THROUGH THESE PERIODS.
MONDAY NIGHT...NW COLORADO SNOWFALL IS EXPECTED TO DIMINISH BUT
NOT NECESSARILY END. WINTER HIGHLIGHTS COULD BE POTENTIALLY BE
EXTENDED INTO THIS PERIOD FOR THE NW CO MTNS.

HIGHLY AMPLIFIED WEST COAST RIDGE AMPLIFIES INLAND TUESDAY INTO
WEDNESDAY.

BY THURSDAY THE NEXT NORTHERN PACIFIC WAVE WORKS INTO THE GREAT
BASIN. THE EC IS DEEPER AND COLDER WITH THIS SYSTEM WHILE THE GFS
KEEPS MOST OF ITS ENERGY IN THE NORTHERN ROCKIES. CONFIDENCE IS
HIGH FOR THE NORTHERN ZONES TO RECEIVE SOME SNOWFALL INTO
FRIDAY...WHILE CONFIDENCE LOWERS SOMEWHAT INTO THE CENTRAL AND
SOUTHERN ZONES. SNOW LEVELS START OUT HIGH ON CHRISTMAS DAY THEN
LOWER OVERNIGHT. HIGHLIGHTS ARE EXPECTED.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1055 PM MST FRI DEC 19 2014

A FEW LOCATIONS REMAIN WITH 3KFT CIGS INCLUDING KVEL AND KEEO BUT
OTHERWISE CLOUD COVER IS EXPECTED TO REMAIN ELEVATED TONIGHT. HIGH
CLOUDS ARE PUSHING IN FROM THE WEST AND BY 02Z SUNDAY THE ENTIRE
FORECAST AREA WILL BE BKN TO OVC AGAIN. ISO -RA AND -SN WILL BEGIN
TO MOVE INTO NE UT AND NW CO SATURDAY NIGHT.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR COZ008.

     WINTER STORM WATCH FROM LATE SATURDAY NIGHT THROUGH MONDAY
     AFTERNOON FOR COZ004-013.

     WINTER STORM WATCH FROM SUNDAY MORNING THROUGH MONDAY AFTERNOON
     FOR COZ005-010.

UT...NONE.
&&

$$

SHORT TERM...JAD
LONG TERM...JOE
AVIATION...JAM





000
FXUS65 KGJT 200555
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1055 PM MST FRI DEC 19 2014

.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)
ISSUED AT 229 PM MST FRI DEC 19 2014

A WEAK DISTURBANCE AND LOW-LEVEL INSTABILITY GENERATED AREAS OF
LIGHT SNOW THIS MORNING ACROSS WEST-CENTRAL AND NORTHWEST COLORADO.
WE RECEIVED 0.5 INCH OF SNOW HERE AT THE GJT WEATHER OFFICE...THE
FIRST MEASURABLE SNOW AT THE OFFICE SO FAR THIS SEASON.

MOST OF THE AREA WILL REMAIN DRY TONIGHT THROUGH SATURDAY AFTERNOON.
WARM ADVECTIVE HIGH CLOUDS WERE MOVING IN THIS AFTERNOON AHEAD OF A
WEAK WAVE THAT WILL CROSS TONIGHT. ANOTHER PACIFIC TROUGH AND ITS
ASSOCIATED SURFACE COLD FRONT WAS PUSHING ACROSS THROUGH THE PAC NW
AND WESTERN GREAT BASIN THIS AFTERNOON. Q-G DIAGNOSTICS SHOWED THIS
WAVE WEAKENING CONSIDERABLY BY THE TIME IT CROSSES WRN CO SAT
MORNING FOR SCATTERED LIGHT SNOW ACROSS THE NRN MOUNTAINS SAT. MAY
SEE A FEW FLAKES AROUND MEEKER...CRAIG TO STEAMBOAT SPGS AS THE
WESTERLY FLOW ENCOUNTERS THE HIGHER TERRAIN. THESE WAVES WILL NOT BE
STRONG ENOUGH TO FLUSH OUT THE EASTERN UINTA BASIN WHERE LOW CLOUDS
WILL HANG ON.

A STRONG AND MOIST PACIFIC JET PUNCHES INTO WA/OR WITH 310K AND 315K
ISENTROPIC FIELDS SHOWING THE INITIAL MOISTURE PUSH REACHING NE
UT/NW CO SAT NIGHT IN WARM ADVECTION/ISENTROPIC UPGLIDE. MADE ONLY
MINOR CHANGES TO THE CURRENT POP GRIDS WHICH HAVE SNOW BECOMING
WIDESPREAD ACROSS THE NRN MOUNTAINS AFTER MIDNIGHT SAT NIGHT AND
SPREADING INTO THE CENTRAL MTNS BY 12Z SUNDAY. LIKELY TO SEE SOME
LIGHT SNOW IN THE CRAIG/MEEKER/STEAMBOAT AREAS BY 12Z SUNDAY AS
WELL. IN CONTRAST...ONLY A CHANCE OF LIGHT SNOW FOR THE EASTERN
UINTA MTNS SAT NIGHT IN THE SHADOW OF THE HIGHER MTNS TO THEIR
WEST.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 229 PM MST FRI DEC 19 2014

TWO STORMS ARE STILL TIMED TO IMPACT THE REGION SUNDAY THOUGH
MONDAY AND THEN AGAIN CHRISTMAS DAY. DETAILS FOR THE WEEKEND
STORM ARE BETTER RESOLVED FAVORING THE NORTH...ESPECIALLY THE NW
CO MTNS...WITH SIGNIFICANT SNOWFALL. CURRENT HIGHLIGHTS ARE IN
GOOD SHAPE THOUGH SURROUNDING MTN ZONES LOOK LIKE THEY MAY REACH
ADVISORY SNOW AMOUNTS.

SUNDAY IN MILD NW FLOW...MOISTURE DEEPENS OVER THE FORECAST AREA.
700MB SPECIFIC HUMIDITIES CLIMB TO 4 G/KG OVER THE NORTH. SNOW
LEVELS WILL BE A CHALLENGE EXPECTED TO RISE TO AROUND 7KFT IN THE
AFTERNOON. OROGRAPHICS IS THE MAIN FORCING MECHANISM. DENDRITIC
CRYSTAL GROWTH REGION IS NEAR SATURATION BUT IS HIGH AT AROUND
15-17KFT MSL. SO HAVE KEPT THE HIGH POPS FOR SUNDAY BUT LOWERED
SNOW ACCUMULATIONS SOMEWHAT.

SUNDAY NIGHT-MONDAY JET SUPPORT NOSES IN FROM THE NW WITH COLD
ADVECTION LOWERING 700MB TEMPS FROM -6 TO -10. DENDRITIC LAYER
LOWERS TO AROUND 11KFT MSL. THE GFS IS PRODUCING OVER A FOOT OF
SNOW OVER THE PARK GORE FLAT TOP RANGES THROUGH THESE PERIODS.
MONDAY NIGHT...NW COLORADO SNOWFALL IS EXPECTED TO DIMINISH BUT
NOT NECESSARILY END. WINTER HIGHLIGHTS COULD BE POTENTIALLY BE
EXTENDED INTO THIS PERIOD FOR THE NW CO MTNS.

HIGHLY AMPLIFIED WEST COAST RIDGE AMPLIFIES INLAND TUESDAY INTO
WEDNESDAY.

BY THURSDAY THE NEXT NORTHERN PACIFIC WAVE WORKS INTO THE GREAT
BASIN. THE EC IS DEEPER AND COLDER WITH THIS SYSTEM WHILE THE GFS
KEEPS MOST OF ITS ENERGY IN THE NORTHERN ROCKIES. CONFIDENCE IS
HIGH FOR THE NORTHERN ZONES TO RECEIVE SOME SNOWFALL INTO
FRIDAY...WHILE CONFIDENCE LOWERS SOMEWHAT INTO THE CENTRAL AND
SOUTHERN ZONES. SNOW LEVELS START OUT HIGH ON CHRISTMAS DAY THEN
LOWER OVERNIGHT. HIGHLIGHTS ARE EXPECTED.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1055 PM MST FRI DEC 19 2014

A FEW LOCATIONS REMAIN WITH 3KFT CIGS INCLUDING KVEL AND KEEO BUT
OTHERWISE CLOUD COVER IS EXPECTED TO REMAIN ELEVATED TONIGHT. HIGH
CLOUDS ARE PUSHING IN FROM THE WEST AND BY 02Z SUNDAY THE ENTIRE
FORECAST AREA WILL BE BKN TO OVC AGAIN. ISO -RA AND -SN WILL BEGIN
TO MOVE INTO NE UT AND NW CO SATURDAY NIGHT.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR COZ008.

     WINTER STORM WATCH FROM LATE SATURDAY NIGHT THROUGH MONDAY
     AFTERNOON FOR COZ004-013.

     WINTER STORM WATCH FROM SUNDAY MORNING THROUGH MONDAY AFTERNOON
     FOR COZ005-010.

UT...NONE.
&&

$$

SHORT TERM...JAD
LONG TERM...JOE
AVIATION...JAM




000
FXUS65 KGJT 192247
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
347 PM MST FRI DEC 19 2014

.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)
ISSUED AT 229 PM MST FRI DEC 19 2014

A WEAK DISTURBANCE AND LOW-LEVEL INSTABILITY GENERATED AREAS OF
LIGHT SNOW THIS MORNING ACROSS WEST-CENTRAL AND NORTHWEST COLORADO.
WE RECEIVED 0.5 INCH OF SNOW HERE AT THE GJT WEATHER OFFICE...THE
FIRST MEASURABLE SNOW AT THE OFFICE SO FAR THIS SEASON.

MOST OF THE AREA WILL REMAIN DRY TONIGHT THROUGH SATURDAY AFTERNOON.
WARM ADVECTIVE HIGH CLOUDS WERE MOVING IN THIS AFTERNOON AHEAD OF A
WEAK WAVE THAT WILL CROSS TONIGHT. ANOTHER PACIFIC TROUGH AND ITS
ASSOCIATED SURFACE COLD FRONT WAS PUSHING ACROSS THROUGH THE PAC NW
AND WESTERN GREAT BASIN THIS AFTERNOON. Q-G DIAGNOSTICS SHOWED THIS
WAVE WEAKENING CONSIDERABLY BY THE TIME IT CROSSES WRN CO SAT
MORNING FOR SCATTERED LIGHT SNOW ACROSS THE NRN MOUNTAINS SAT. MAY
SEE A FEW FLAKES AROUND MEEKER...CRAIG TO STEAMBOAT SPGS AS THE
WESTERLY FLOW ENCOUNTERS THE HIGHER TERRAIN. THESE WAVES WILL NOT BE
STRONG ENOUGH TO FLUSH OUT THE EASTERN UINTA BASIN WHERE LOW CLOUDS
WILL HANG ON.

A STRONG AND MOIST PACIFIC JET PUNCHES INTO WA/OR WITH 310K AND 315K
ISENTROPIC FIELDS SHOWING THE INITIAL MOISTURE PUSH REACHING NE
UT/NW CO SAT NIGHT IN WARM ADVECTION/ISENTROPIC UPGLIDE. MADE ONLY
MINOR CHANGES TO THE CURRENT POP GRIDS WHICH HAVE SNOW BECOMING
WIDESPREAD ACROSS THE NRN MOUNTAINS AFTER MIDNIGHT SAT NIGHT AND
SPREADING INTO THE CENTRAL MTNS BY 12Z SUNDAY. LIKELY TO SEE SOME
LIGHT SNOW IN THE CRAIG/MEEKER/STEAMBOAT AREAS BY 12Z SUNDAY AS
WELL. IN CONTRAST...ONLY A CHANCE OF LIGHT SNOW FOR THE EASTERN
UINTA MTNS SAT NIGHT IN THE SHADOW OF THE HIGHER MTNS TO THEIR
WEST.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 229 PM MST FRI DEC 19 2014

TWO STORMS ARE STILL TIMED TO IMPACT THE REGION SUNDAY THOUGH
MONDAY AND THEN AGAIN CHRISTMAS DAY. DETAILS FOR THE WEEKEND
STORM ARE BETTER RESOLVED FAVORING THE NORTH...ESPECIALLY THE NW
CO MTNS...WITH SIGNIFICANT SNOWFALL. CURRENT HIGHLIGHTS ARE IN
GOOD SHAPE THOUGH SURROUNDING MTN ZONES LOOK LIKE THEY MAY REACH
ADVISORY SNOW AMOUNTS.

SUNDAY IN MILD NW FLOW...MOISTURE DEEPENS OVER THE FORECAST AREA.
700MB SPECIFIC HUMIDITIES CLIMB TO 4 G/KG OVER THE NORTH. SNOW
LEVELS WILL BE A CHALLENGE EXPECTED TO RISE TO AROUND 7KFT IN THE
AFTERNOON. OROGRAPHICS IS THE MAIN FORCING MECHANISM. DENDRITIC
CRYSTAL GROWTH REGION IS NEAR SATURATION BUT IS HIGH AT AROUND
15-17KFT MSL. SO HAVE KEPT THE HIGH POPS FOR SUNDAY BUT LOWERED
SNOW ACCUMULATIONS SOMEWHAT.

SUNDAY NIGHT-MONDAY JET SUPPORT NOSES IN FROM THE NW WITH COLD
ADVECTION LOWERING 700MB TEMPS FROM -6 TO -10. DENDRITIC LAYER
LOWERS TO AROUND 11KFT MSL. THE GFS IS PRODUCING OVER A FOOT OF
SNOW OVER THE PARK GORE FLAT TOP RANGES THROUGH THESE PERIODS.
MONDAY NIGHT...NW COLORADO SNOWFALL IS EXPECTED TO DIMINISH BUT
NOT NECESSARILY END. WINTER HIGHLIGHTS COULD BE POTENTIALLY BE
EXTENDED INTO THIS PERIOD FOR THE NW CO MTNS.

HIGHLY AMPLIFIED WEST COAST RIDGE AMPLIFIES INLAND TUESDAY INTO
WEDNESDAY.

BY THURSDAY THE NEXT NORTHERN PACIFIC WAVE WORKS INTO THE GREAT
BASIN. THE EC IS DEEPER AND COLDER WITH THIS SYSTEM WHILE THE GFS
KEEPS MOST OF ITS ENERGY IN THE NORTHERN ROCKIES. CONFIDENCE IS
HIGH FOR THE NORTHERN ZONES TO RECEIVE SOME SNOWFALL INTO
FRIDAY...WHILE CONFIDENCE LOWERS SOMEWHAT INTO THE CENTRAL AND
SOUTHERN ZONES. SNOW LEVELS START OUT HIGH ON CHRISTMAS DAY THEN
LOWER OVERNIGHT. HIGHLIGHTS ARE EXPECTED.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 347 PM MST FRI DEC 19 2014

LOW LEVEL MOISTURE CONTINUES TO HANG OUT ACROSS EASTERN UTAH AND
WESTERN COLORADO THIS AFTERNOON. HOWEVER ENOUGH MIXING WITH
INSTABILITY ALOFT IS IN PLACE THAT KVEL IS THE ONLY LOCATION LEFT
WITH MVFR CIGS. WITH THIS MOISTURE ROOTED IN THE BASIN EXPECT
THESE CONDITIONS TO HOLD THROUGH THE NIGHT INTO TOMORROW MORNING.
HIGH CLOUDINESS WILL BE DRIFTING THROUGH IN WAVES WITH A BREAK
LATE THIS EVENING THROUGH EARLY MORNING. NOT ENTIRELY CONFIDENT ON
WHAT WILL HAPPEN IN THE BREAK AS FAR AS FOG OR CLOUD FORMATION.
FOR NOW WILL KEEP OPTIMISTIC FORECAST GOING.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR COZ008.

     WINTER STORM WATCH FROM LATE SATURDAY NIGHT THROUGH MONDAY
     AFTERNOON FOR COZ004-013.

     WINTER STORM WATCH FROM SUNDAY MORNING THROUGH MONDAY AFTERNOON
     FOR COZ005-010.

UT...NONE.
&&

$$

SHORT TERM...JAD
LONG TERM...JOE
AVIATION...TGJT




000
FXUS65 KGJT 192247
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
347 PM MST FRI DEC 19 2014

.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)
ISSUED AT 229 PM MST FRI DEC 19 2014

A WEAK DISTURBANCE AND LOW-LEVEL INSTABILITY GENERATED AREAS OF
LIGHT SNOW THIS MORNING ACROSS WEST-CENTRAL AND NORTHWEST COLORADO.
WE RECEIVED 0.5 INCH OF SNOW HERE AT THE GJT WEATHER OFFICE...THE
FIRST MEASURABLE SNOW AT THE OFFICE SO FAR THIS SEASON.

MOST OF THE AREA WILL REMAIN DRY TONIGHT THROUGH SATURDAY AFTERNOON.
WARM ADVECTIVE HIGH CLOUDS WERE MOVING IN THIS AFTERNOON AHEAD OF A
WEAK WAVE THAT WILL CROSS TONIGHT. ANOTHER PACIFIC TROUGH AND ITS
ASSOCIATED SURFACE COLD FRONT WAS PUSHING ACROSS THROUGH THE PAC NW
AND WESTERN GREAT BASIN THIS AFTERNOON. Q-G DIAGNOSTICS SHOWED THIS
WAVE WEAKENING CONSIDERABLY BY THE TIME IT CROSSES WRN CO SAT
MORNING FOR SCATTERED LIGHT SNOW ACROSS THE NRN MOUNTAINS SAT. MAY
SEE A FEW FLAKES AROUND MEEKER...CRAIG TO STEAMBOAT SPGS AS THE
WESTERLY FLOW ENCOUNTERS THE HIGHER TERRAIN. THESE WAVES WILL NOT BE
STRONG ENOUGH TO FLUSH OUT THE EASTERN UINTA BASIN WHERE LOW CLOUDS
WILL HANG ON.

A STRONG AND MOIST PACIFIC JET PUNCHES INTO WA/OR WITH 310K AND 315K
ISENTROPIC FIELDS SHOWING THE INITIAL MOISTURE PUSH REACHING NE
UT/NW CO SAT NIGHT IN WARM ADVECTION/ISENTROPIC UPGLIDE. MADE ONLY
MINOR CHANGES TO THE CURRENT POP GRIDS WHICH HAVE SNOW BECOMING
WIDESPREAD ACROSS THE NRN MOUNTAINS AFTER MIDNIGHT SAT NIGHT AND
SPREADING INTO THE CENTRAL MTNS BY 12Z SUNDAY. LIKELY TO SEE SOME
LIGHT SNOW IN THE CRAIG/MEEKER/STEAMBOAT AREAS BY 12Z SUNDAY AS
WELL. IN CONTRAST...ONLY A CHANCE OF LIGHT SNOW FOR THE EASTERN
UINTA MTNS SAT NIGHT IN THE SHADOW OF THE HIGHER MTNS TO THEIR
WEST.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 229 PM MST FRI DEC 19 2014

TWO STORMS ARE STILL TIMED TO IMPACT THE REGION SUNDAY THOUGH
MONDAY AND THEN AGAIN CHRISTMAS DAY. DETAILS FOR THE WEEKEND
STORM ARE BETTER RESOLVED FAVORING THE NORTH...ESPECIALLY THE NW
CO MTNS...WITH SIGNIFICANT SNOWFALL. CURRENT HIGHLIGHTS ARE IN
GOOD SHAPE THOUGH SURROUNDING MTN ZONES LOOK LIKE THEY MAY REACH
ADVISORY SNOW AMOUNTS.

SUNDAY IN MILD NW FLOW...MOISTURE DEEPENS OVER THE FORECAST AREA.
700MB SPECIFIC HUMIDITIES CLIMB TO 4 G/KG OVER THE NORTH. SNOW
LEVELS WILL BE A CHALLENGE EXPECTED TO RISE TO AROUND 7KFT IN THE
AFTERNOON. OROGRAPHICS IS THE MAIN FORCING MECHANISM. DENDRITIC
CRYSTAL GROWTH REGION IS NEAR SATURATION BUT IS HIGH AT AROUND
15-17KFT MSL. SO HAVE KEPT THE HIGH POPS FOR SUNDAY BUT LOWERED
SNOW ACCUMULATIONS SOMEWHAT.

SUNDAY NIGHT-MONDAY JET SUPPORT NOSES IN FROM THE NW WITH COLD
ADVECTION LOWERING 700MB TEMPS FROM -6 TO -10. DENDRITIC LAYER
LOWERS TO AROUND 11KFT MSL. THE GFS IS PRODUCING OVER A FOOT OF
SNOW OVER THE PARK GORE FLAT TOP RANGES THROUGH THESE PERIODS.
MONDAY NIGHT...NW COLORADO SNOWFALL IS EXPECTED TO DIMINISH BUT
NOT NECESSARILY END. WINTER HIGHLIGHTS COULD BE POTENTIALLY BE
EXTENDED INTO THIS PERIOD FOR THE NW CO MTNS.

HIGHLY AMPLIFIED WEST COAST RIDGE AMPLIFIES INLAND TUESDAY INTO
WEDNESDAY.

BY THURSDAY THE NEXT NORTHERN PACIFIC WAVE WORKS INTO THE GREAT
BASIN. THE EC IS DEEPER AND COLDER WITH THIS SYSTEM WHILE THE GFS
KEEPS MOST OF ITS ENERGY IN THE NORTHERN ROCKIES. CONFIDENCE IS
HIGH FOR THE NORTHERN ZONES TO RECEIVE SOME SNOWFALL INTO
FRIDAY...WHILE CONFIDENCE LOWERS SOMEWHAT INTO THE CENTRAL AND
SOUTHERN ZONES. SNOW LEVELS START OUT HIGH ON CHRISTMAS DAY THEN
LOWER OVERNIGHT. HIGHLIGHTS ARE EXPECTED.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 347 PM MST FRI DEC 19 2014

LOW LEVEL MOISTURE CONTINUES TO HANG OUT ACROSS EASTERN UTAH AND
WESTERN COLORADO THIS AFTERNOON. HOWEVER ENOUGH MIXING WITH
INSTABILITY ALOFT IS IN PLACE THAT KVEL IS THE ONLY LOCATION LEFT
WITH MVFR CIGS. WITH THIS MOISTURE ROOTED IN THE BASIN EXPECT
THESE CONDITIONS TO HOLD THROUGH THE NIGHT INTO TOMORROW MORNING.
HIGH CLOUDINESS WILL BE DRIFTING THROUGH IN WAVES WITH A BREAK
LATE THIS EVENING THROUGH EARLY MORNING. NOT ENTIRELY CONFIDENT ON
WHAT WILL HAPPEN IN THE BREAK AS FAR AS FOG OR CLOUD FORMATION.
FOR NOW WILL KEEP OPTIMISTIC FORECAST GOING.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR COZ008.

     WINTER STORM WATCH FROM LATE SATURDAY NIGHT THROUGH MONDAY
     AFTERNOON FOR COZ004-013.

     WINTER STORM WATCH FROM SUNDAY MORNING THROUGH MONDAY AFTERNOON
     FOR COZ005-010.

UT...NONE.
&&

$$

SHORT TERM...JAD
LONG TERM...JOE
AVIATION...TGJT





000
FXUS65 KGJT 192131
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
231 PM MST FRI DEC 19 2014

.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)
ISSUED AT 229 PM MST FRI DEC 19 2014

A WEAK DISTURBANCE AND LOW-LEVEL INSTABILITY GENERATED AREAS OF
LIGHT SNOW THIS MORNING ACROSS WEST-CENTRAL AND NORTHWEST COLORADO.
WE RECEIVED 0.5 INCH OF SNOW HERE AT THE GJT WEATHER OFFICE...THE
FIRST MEASURABLE SNOW AT THE OFFICE SO FAR THIS SEASON.

MOST OF THE AREA WILL REMAIN DRY TONIGHT THROUGH SATURDAY AFTERNOON.
WARM ADVECTIVE HIGH CLOUDS WERE MOVING IN THIS AFTERNOON AHEAD OF A
WEAK WAVE THAT WILL CROSS TONIGHT. ANOTHER PACIFIC TROUGH AND ITS
ASSOCIATED SURFACE COLD FRONT WAS PUSHING ACROSS THROUGH THE PAC NW
AND WESTERN GREAT BASIN THIS AFTERNOON. Q-G DIAGNOSTICS SHOWED THIS
WAVE WEAKENING CONSIDERABLY BY THE TIME IT CROSSES WRN CO SAT
MORNING FOR SCATTERED LIGHT SNOW ACROSS THE NRN MOUNTAINS SAT. MAY
SEE A FEW FLAKES AROUND MEEKER...CRAIG TO STEAMBOAT SPGS AS THE
WESTERLY FLOW ENCOUNTERS THE HIGHER TERRAIN. THESE WAVES WILL NOT BE
STRONG ENOUGH TO FLUSH OUT THE EASTERN UINTA BASIN WHERE LOW CLOUDS
WILL HANG ON.

A STRONG AND MOIST PACIFIC JET PUNCHES INTO WA/OR WITH 310K AND 315K
ISENTROPIC FIELDS SHOWING THE INITIAL MOISTURE PUSH REACHING NE
UT/NW CO SAT NIGHT IN WARM ADVECTION/ISENTROPIC UPGLIDE. MADE ONLY
MINOR CHANGES TO THE CURRENT POP GRIDS WHICH HAVE SNOW BECOMING
WIDESPREAD ACROSS THE NRN MOUNTAINS AFTER MIDNIGHT SAT NIGHT AND
SPREADING INTO THE CENTRAL MTNS BY 12Z SUNDAY. LIKELY TO SEE SOME
LIGHT SNOW IN THE CRAIG/MEEKER/STEAMBOAT AREAS BY 12Z SUNDAY AS
WELL. IN CONTRAST...ONLY A CHANCE OF LIGHT SNOW FOR THE EASTERN
UINTA MTNS SAT NIGHT IN THE SHADOW OF THE HIGHER MTNS TO THEIR
WEST.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 229 PM MST FRI DEC 19 2014

TWO STORMS ARE STILL TIMED TO IMPACT THE REGION SUNDAY THOUGH
MONDAY AND THEN AGAIN CHRISTMAS DAY. DETAILS FOR THE WEEKEND
STORM ARE BETTER RESOLVED FAVORING THE NORTH...ESPECIALLY THE NW
CO MTNS...WITH SIGNIFICANT SNOWFALL. CURRENT HIGHLIGHTS ARE IN
GOOD SHAPE THOUGH SURROUNDING MTN ZONES LOOK LIKE THEY MAY REACH
ADVISORY SNOW AMOUNTS.

SUNDAY IN MILD NW FLOW...MOISTURE DEEPENS OVER THE FORECAST AREA.
700MB SPECIFIC HUMIDITIES CLIMB TO 4 G/KG OVER THE NORTH. SNOW
LEVELS WILL BE A CHALLENGE EXPECTED TO RISE TO AROUND 7KFT IN THE
AFTERNOON. OROGRAPHICS IS THE MAIN FORCING MECHANISM. DENDRITIC
CRYSTAL GROWTH REGION IS NEAR SATURATION BUT IS HIGH AT AROUND
15-17KFT MSL. SO HAVE KEPT THE HIGH POPS FOR SUNDAY BUT LOWERED
SNOW ACCUMULATIONS SOMEWHAT.

SUNDAY NIGHT-MONDAY JET SUPPORT NOSES IN FROM THE NW WITH COLD
ADVECTION LOWERING 700MB TEMPS FROM -6 TO -10. DENDRITIC LAYER
LOWERS TO AROUND 11KFT MSL. THE GFS IS PRODUCING OVER A FOOT OF
SNOW OVER THE PARK GORE FLAT TOP RANGES THROUGH THESE PERIODS.
MONDAY NIGHT...NW COLORADO SNOWFALL IS EXPECTED TO DIMINISH BUT
NOT NECESSARILY END. WINTER HIGHLIGHTS COULD BE POTENTIALLY BE
EXTENDED INTO THIS PERIOD FOR THE NW CO MTNS.

HIGHLY AMPLIFIED WEST COAST RIDGE AMPLIFIES INLAND TUESDAY INTO
WEDNESDAY.

BY THURSDAY THE NEXT NORTHERN PACIFIC WAVE WORKS INTO THE GREAT
BASIN. THE EC IS DEEPER AND COLDER WITH THIS SYSTEM WHILE THE GFS
KEEPS MOST OF ITS ENERGY IN THE NORTHERN ROCKIES. CONFIDENCE IS
HIGH FOR THE NORTHERN ZONES TO RECEIVE SOME SNOWFALL INTO
FRIDAY...WHILE CONFIDENCE LOWERS SOMEWHAT INTO THE CENTRAL AND
SOUTHERN ZONES. SNOW LEVELS START OUT HIGH ON CHRISTMAS DAY THEN
LOWER OVERNIGHT. HIGHLIGHTS ARE EXPECTED.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 958 AM MST FRI DEC 19 2014

AREAS OF LIGHT SNOW WILL PERSIST OVER THE NRN CO MTNS INTO MID-
AFTERNOON BUT DIMINISH ELSEWHERE AS A WEAK DISTURBANCE EXITS TO THE
EAST. LOW CLOUDS CURRENTLY ENTRENCHED IN MANY VALLEYS MAY BE
STUBBORN TO LEAVE...THOUGH DO EXPECT VFR CONDITIONS TO DEVELOP AT
THE TAF SITES...AND MOST AIRFIELDS... BY 21Z IF NOT SOONER THIS
AFTERNOON. A COUPLE OF WEAKENING UPPER DISTURBANCES WILL IMPACT
THE AREA...ONE TONIGHT AND ANOTHER ON SATURDAY FOR THE POTENTIAL
OF MVFR CIGS AT TIMES OVER AT LEAST THE NORTHERN MTNS.


&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR COZ008.

     WINTER STORM WATCH FROM LATE SATURDAY NIGHT THROUGH MONDAY
     AFTERNOON FOR COZ004-013.

     WINTER STORM WATCH FROM SUNDAY MORNING THROUGH MONDAY AFTERNOON
     FOR COZ005-010.

UT...NONE.
&&

$$

SHORT TERM...JAD
LONG TERM...JOE
AVIATION...JAD




000
FXUS65 KGJT 191701
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1001 AM MST FRI DEC 19 2014

AVIATION SECTION UPDATED

.UPDATE...
ISSUED AT 742 AM MST FRI DEC 19 2014

A WEAK DISTURBANCE SEEN IN SATELLITE WATER VAPOR WAS CROSSING WRN
CO EARLY THIS MORNING GENERATING AREAS OF LIGHT SNOW IN A NEUTRAL
TO WEAKLY UNSTABLE ENVIRONMENT ALOFT PER THIS MORNINGS SOUNDING.
SNOW WILL GENERALLY BE JUST A DUSTING BUT ENOUGH TO BRING SOME
WHITENESS AT LEAST TEMPORARILY. AREAS OF FOG ALSO PRESENT THIS
MORNING. EXPECT THE MAJORITY OF THIS LIGHT SNOW TO END BY MIDDAY.
HAVE UPDATED GRIDDED FORECAST TO REFLECT CURRENT AND EXPECTED
CONDITIONS THIS MORNING.

&&

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 420 AM MST FRI DEC 19 2014

STILL HANGING ONTO A FEW ISOLATED SNOW SHOWERS ACROSS THE
BOOKCLIFFS AT MEEKER...SUNLIGHT...AND ASPEN THIS MORNING. FOG HAS
INTERMITTENTLY BEEN REDUCED TO A HALF MILE AT TIMES AT CRAIG THIS
MORNING BUT MOST LOCATIONS ARE STAYING OUT OF THE SOUP. WEAK
TRANSITORY RIDGING WILL BUILD INTO THE REGION TODAY...BUT BY THIS
EVENING MID TO HIGH LEVEL CLOUDS WILL BEGIN MOVING IN FROM THE
WEST. A FEW ISOLATED SHOWERS ARE POSSIBLE ON SATURDAY MORNING AHEAD
OF THE MAIN MOISTURE OVER NE UTAH AND NW COLORADO MOUNTAINS...BUT
THE MORE INTERESTING WEATHER IS IN THE FOLLOWING LONG TERM
SECTION.

.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 420 AM MST FRI DEC 19 2014

MOIST NORTHWEST FLOW WILL BE SETTLING IN OVER THE FORECAST AREA
SATURDAY NIGHT WITH A SLOW SOUTHWARD PROGRESSION INTO OUR CENTRAL
MOUNTAINS BY EARLY SUNDAY MORNING. STRONG UPPER LEVEL JET SLOPES
INTO THE AREA...PROVIDING DYNAMIC SUPPORT. MODELS REMAIN VERY
AGGRESSIVE WITH QPF VALUES WITH SNOWFALL ACCUMULATIONS EXCEEDING
A FOOT OVER A LARGE PORTION OF OUR NORTHERN AND CENTRAL MOUNTAINS
FROM VAIL NORTH TO THE WYOMING STATE LINE. FAVORED WEST AND
NORTHWEST SLOPES COULD EXCEED 2 FEET BY LATE MONDAY AS 30-40 KTS
H7 FLOW PROVIDES FAVORABLE OROGRAPHIC FLOW AND WORKS TO SQUEEZE
OUT ALL AVAILABLE MOISTURE ALONG AND WEST OF THE CONTINENTAL
DIVIDE. INITIAL SURGE FAVORS THE NORTHERN AND CENTRAL MOUNTAINS
BUT THE JET IS EXPECTED TO SAG SOUTH A BIT MORE THAN FORECAST AND
DRIVE MOISTURE SOUTHWARD INTO THE SAN JUANS BY SUNDAY
NIGHT...ALTHOUGH POTENTIAL SNOWFALL AMOUNTS WILL BE ABOUT HALF OF
WHAT WE CAN EXPECT OVER THE NORTH.

WITH HOLIDAY TRAVEL PICKING UP THIS WEEKEND...WE WENT AHEAD AND
ISSUED A WINTER STORM WATCH FOR THE NORTHERN AND CENTRAL MOUNTAINS
IN WESTERN COLORADO LATE IN THE 4TH AND 5TH PERIODS OF THE
FORECAST. WILL NEED TO WATCH SHOT OF WAA ON SUNDAY WHICH MAY SLOW
POTENTIAL SNOWFALL A BIT...BUT SERIES OF FAST MOVING PACIFIC WAVES
WILL EVENTUALLY SEND IN A LITTLE COOLER AIR ALOFT AND KEEP
SNOWFALL EFFICIENCY HIGH THROUGH EARLY MONDAY. NEW NAM IS A LITTLE
FAST...ADVERTISING A BREAK LATE MONDAY AND MONDAY NIGHT WITH THE
GFS A LITTLE SLOWER SHOWING SOME DRAG TO THE MOISTURE AND APPEARS
TO BE MORE REASONABLE BASED ON PREVIOUS EVENTS OF SIMILAR NATURE.

FLAT RIDGING SLIDES THROUGH TUESDAY AND WEDNESDAY AHEAD OF YET
ANOTHER POTENTIAL SYSTEM THAT IS EXPECTED TO ARRIVE BY CHRISTMAS
MORNING. THE GFS AND ECMWF CONTINUE TO JUMP AROUND FROM RUN TO RUN
WITH THE NEW ECMWF BACK TO SHOWING A CLOSED LOW MOVING OVER THE
FORECAST AREA ON CHRISTMAS. GFS HINTING AT MORE OF A SPLITTING
SYSTEM SENDING ENERGY NORTH AND SOUTH...WITH THE SOUTHERN SYSTEM
ROLLING ACROSS OUR FORECAST AREA. EITHER SCENARIO WOULD BRING
PRECIPITATION TO MUCH OF EASTERN UTAH AND WESTERN COLORADO...BUT
WITH SOME UNCERTAINTY STILL EVIDENT...WILL RUN WITH BLENDED POP
SOLUTIONS...WHICH OFFER SLIGHT CHANCE TO CHANCE POPS FOR NOW.
TEMPS COOL DOWN BEHIND THE CHRISTMAS SYSTEM.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 958 AM MST FRI DEC 19 2014

AREAS OF LIGHT SNOW WILL PERSIST OVER THE NRN CO MTNS INTO MID-
AFTERNOON BUT DIMINISH ELSEWHERE AS A WEAK DISTURBANCE EXITS TO THE
EAST. LOW CLOUDS CURRENTLY ENTRENCHED IN MANY VALLEYS MAY BE
STUBBORN TO LEAVE...THOUGH DO EXPECT VFR CONDITIONS TO DEVELOP AT
THE TAF SITES...AND MOST AIRFIELDS... BY 21Z IF NOT SOONER THIS
AFTERNOON. A COUPLE OF WEAKENING UPPER DISTURBANCES WILL IMPACT
THE AREA...ONE TONIGHT AND ANOTHER ON SATURDAY FOR THE POTENTIAL
OF MVFR CIGS AT TIMES OVER AT LEAST THE NORTHERN MTNS.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR COZ008.

     WINTER STORM WATCH FROM LATE SATURDAY NIGHT THROUGH MONDAY
     AFTERNOON FOR COZ004-013.

     WINTER STORM WATCH FROM SUNDAY MORNING THROUGH MONDAY AFTERNOON
     FOR COZ005-010.

UT...NONE.
&&

$$

UPDATE...JAD
SHORT TERM...JAM
LONG TERM...JDC
AVIATION...JAD





000
FXUS65 KGJT 191701
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1001 AM MST FRI DEC 19 2014

AVIATION SECTION UPDATED

.UPDATE...
ISSUED AT 742 AM MST FRI DEC 19 2014

A WEAK DISTURBANCE SEEN IN SATELLITE WATER VAPOR WAS CROSSING WRN
CO EARLY THIS MORNING GENERATING AREAS OF LIGHT SNOW IN A NEUTRAL
TO WEAKLY UNSTABLE ENVIRONMENT ALOFT PER THIS MORNINGS SOUNDING.
SNOW WILL GENERALLY BE JUST A DUSTING BUT ENOUGH TO BRING SOME
WHITENESS AT LEAST TEMPORARILY. AREAS OF FOG ALSO PRESENT THIS
MORNING. EXPECT THE MAJORITY OF THIS LIGHT SNOW TO END BY MIDDAY.
HAVE UPDATED GRIDDED FORECAST TO REFLECT CURRENT AND EXPECTED
CONDITIONS THIS MORNING.

&&

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 420 AM MST FRI DEC 19 2014

STILL HANGING ONTO A FEW ISOLATED SNOW SHOWERS ACROSS THE
BOOKCLIFFS AT MEEKER...SUNLIGHT...AND ASPEN THIS MORNING. FOG HAS
INTERMITTENTLY BEEN REDUCED TO A HALF MILE AT TIMES AT CRAIG THIS
MORNING BUT MOST LOCATIONS ARE STAYING OUT OF THE SOUP. WEAK
TRANSITORY RIDGING WILL BUILD INTO THE REGION TODAY...BUT BY THIS
EVENING MID TO HIGH LEVEL CLOUDS WILL BEGIN MOVING IN FROM THE
WEST. A FEW ISOLATED SHOWERS ARE POSSIBLE ON SATURDAY MORNING AHEAD
OF THE MAIN MOISTURE OVER NE UTAH AND NW COLORADO MOUNTAINS...BUT
THE MORE INTERESTING WEATHER IS IN THE FOLLOWING LONG TERM
SECTION.

.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 420 AM MST FRI DEC 19 2014

MOIST NORTHWEST FLOW WILL BE SETTLING IN OVER THE FORECAST AREA
SATURDAY NIGHT WITH A SLOW SOUTHWARD PROGRESSION INTO OUR CENTRAL
MOUNTAINS BY EARLY SUNDAY MORNING. STRONG UPPER LEVEL JET SLOPES
INTO THE AREA...PROVIDING DYNAMIC SUPPORT. MODELS REMAIN VERY
AGGRESSIVE WITH QPF VALUES WITH SNOWFALL ACCUMULATIONS EXCEEDING
A FOOT OVER A LARGE PORTION OF OUR NORTHERN AND CENTRAL MOUNTAINS
FROM VAIL NORTH TO THE WYOMING STATE LINE. FAVORED WEST AND
NORTHWEST SLOPES COULD EXCEED 2 FEET BY LATE MONDAY AS 30-40 KTS
H7 FLOW PROVIDES FAVORABLE OROGRAPHIC FLOW AND WORKS TO SQUEEZE
OUT ALL AVAILABLE MOISTURE ALONG AND WEST OF THE CONTINENTAL
DIVIDE. INITIAL SURGE FAVORS THE NORTHERN AND CENTRAL MOUNTAINS
BUT THE JET IS EXPECTED TO SAG SOUTH A BIT MORE THAN FORECAST AND
DRIVE MOISTURE SOUTHWARD INTO THE SAN JUANS BY SUNDAY
NIGHT...ALTHOUGH POTENTIAL SNOWFALL AMOUNTS WILL BE ABOUT HALF OF
WHAT WE CAN EXPECT OVER THE NORTH.

WITH HOLIDAY TRAVEL PICKING UP THIS WEEKEND...WE WENT AHEAD AND
ISSUED A WINTER STORM WATCH FOR THE NORTHERN AND CENTRAL MOUNTAINS
IN WESTERN COLORADO LATE IN THE 4TH AND 5TH PERIODS OF THE
FORECAST. WILL NEED TO WATCH SHOT OF WAA ON SUNDAY WHICH MAY SLOW
POTENTIAL SNOWFALL A BIT...BUT SERIES OF FAST MOVING PACIFIC WAVES
WILL EVENTUALLY SEND IN A LITTLE COOLER AIR ALOFT AND KEEP
SNOWFALL EFFICIENCY HIGH THROUGH EARLY MONDAY. NEW NAM IS A LITTLE
FAST...ADVERTISING A BREAK LATE MONDAY AND MONDAY NIGHT WITH THE
GFS A LITTLE SLOWER SHOWING SOME DRAG TO THE MOISTURE AND APPEARS
TO BE MORE REASONABLE BASED ON PREVIOUS EVENTS OF SIMILAR NATURE.

FLAT RIDGING SLIDES THROUGH TUESDAY AND WEDNESDAY AHEAD OF YET
ANOTHER POTENTIAL SYSTEM THAT IS EXPECTED TO ARRIVE BY CHRISTMAS
MORNING. THE GFS AND ECMWF CONTINUE TO JUMP AROUND FROM RUN TO RUN
WITH THE NEW ECMWF BACK TO SHOWING A CLOSED LOW MOVING OVER THE
FORECAST AREA ON CHRISTMAS. GFS HINTING AT MORE OF A SPLITTING
SYSTEM SENDING ENERGY NORTH AND SOUTH...WITH THE SOUTHERN SYSTEM
ROLLING ACROSS OUR FORECAST AREA. EITHER SCENARIO WOULD BRING
PRECIPITATION TO MUCH OF EASTERN UTAH AND WESTERN COLORADO...BUT
WITH SOME UNCERTAINTY STILL EVIDENT...WILL RUN WITH BLENDED POP
SOLUTIONS...WHICH OFFER SLIGHT CHANCE TO CHANCE POPS FOR NOW.
TEMPS COOL DOWN BEHIND THE CHRISTMAS SYSTEM.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 958 AM MST FRI DEC 19 2014

AREAS OF LIGHT SNOW WILL PERSIST OVER THE NRN CO MTNS INTO MID-
AFTERNOON BUT DIMINISH ELSEWHERE AS A WEAK DISTURBANCE EXITS TO THE
EAST. LOW CLOUDS CURRENTLY ENTRENCHED IN MANY VALLEYS MAY BE
STUBBORN TO LEAVE...THOUGH DO EXPECT VFR CONDITIONS TO DEVELOP AT
THE TAF SITES...AND MOST AIRFIELDS... BY 21Z IF NOT SOONER THIS
AFTERNOON. A COUPLE OF WEAKENING UPPER DISTURBANCES WILL IMPACT
THE AREA...ONE TONIGHT AND ANOTHER ON SATURDAY FOR THE POTENTIAL
OF MVFR CIGS AT TIMES OVER AT LEAST THE NORTHERN MTNS.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR COZ008.

     WINTER STORM WATCH FROM LATE SATURDAY NIGHT THROUGH MONDAY
     AFTERNOON FOR COZ004-013.

     WINTER STORM WATCH FROM SUNDAY MORNING THROUGH MONDAY AFTERNOON
     FOR COZ005-010.

UT...NONE.
&&

$$

UPDATE...JAD
SHORT TERM...JAM
LONG TERM...JDC
AVIATION...JAD




000
FXUS65 KGJT 191528 CCA
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
827 AM MST FRI DEC 19 2014

CORRECTED UPDATED AVIATION SECTION TO REMOVE STRAY WORDS

.UPDATE...
ISSUED AT 742 AM MST FRI DEC 19 2014

A WEAK DISTURBANCE SEEN IN SATELLITE WATER VAPOR WAS CROSSING WRN
CO EARLY THIS MORNING GENERATING AREAS OF LIGHT SNOW IN A NEUTRAL
TO WEAKLY UNSTABLE ENVIRONMENT ALOFT PER THIS MORNINGS SOUNDING.
SNOW WILL GENERALLY BE JUST A DUSTING BUT ENOUGH TO BRING SOME
WHITENESS AT LEAST TEMPORARILY. AREAS OF FOG ALSO PRESENT THIS
MORNING. EXPECT THE MAJORITY OF THIS LIGHT SNOW TO END BY MIDDAY.
HAVE UPDATED GRIDDED FORECAST TO REFLECT CURRENT AND EXPECTED
CONDITIONS THIS MORNING.

&&

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 420 AM MST FRI DEC 19 2014

STILL HANGING ONTO A FEW ISOLATED SNOW SHOWERS ACROSS THE
BOOKCLIFFS AT MEEKER...SUNLIGHT...AND ASPEN THIS MORNING. FOG HAS
INTERMITTENTLY BEEN REDUCED TO A HALF MILE AT TIMES AT CRAIG THIS
MORNING BUT MOST LOCATIONS ARE STAYING OUT OF THE SOUP. WEAK
TRANSITORY RIDGING WILL BUILD INTO THE REGION TODAY...BUT BY THIS
EVENING MID TO HIGH LEVEL CLOUDS WILL BEGIN MOVING IN FROM THE
WEST. A FEW ISOLATED SHOWERS ARE POSSIBLE ON SATURDAY MORNING AHEAD
OF THE MAIN MOISTURE OVER NE UTAH AND NW COLORADO MOUNTAINS...BUT
THE MORE INTERESTING WEATHER IS IN THE FOLLOWING LONG TERM
SECTION.

.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 420 AM MST FRI DEC 19 2014

MOIST NORTHWEST FLOW WILL BE SETTLING IN OVER THE FORECAST AREA
SATURDAY NIGHT WITH A SLOW SOUTHWARD PROGRESSION INTO OUR CENTRAL
MOUNTAINS BY EARLY SUNDAY MORNING. STRONG UPPER LEVEL JET SLOPES
INTO THE AREA...PROVIDING DYNAMIC SUPPORT. MODELS REMAIN VERY
AGGRESSIVE WITH QPF VALUES WITH SNOWFALL ACCUMULATIONS EXCEEDING
A FOOT OVER A LARGE PORTION OF OUR NORTHERN AND CENTRAL MOUNTAINS
FROM VAIL NORTH TO THE WYOMING STATE LINE. FAVORED WEST AND
NORTHWEST SLOPES COULD EXCEED 2 FEET BY LATE MONDAY AS 30-40 KTS
H7 FLOW PROVIDES FAVORABLE OROGRAPHIC FLOW AND WORKS TO SQUEEZE
OUT ALL AVAILABLE MOISTURE ALONG AND WEST OF THE CONTINENTAL
DIVIDE. INITIAL SURGE FAVORS THE NORTHERN AND CENTRAL MOUNTAINS
BUT THE JET IS EXPECTED TO SAG SOUTH A BIT MORE THAN FORECAST AND
DRIVE MOISTURE SOUTHWARD INTO THE SAN JUANS BY SUNDAY
NIGHT...ALTHOUGH POTENTIAL SNOWFALL AMOUNTS WILL BE ABOUT HALF OF
WHAT WE CAN EXPECT OVER THE NORTH.

WITH HOLIDAY TRAVEL PICKING UP THIS WEEKEND...WE WENT AHEAD AND
ISSUED A WINTER STORM WATCH FOR THE NORTHERN AND CENTRAL MOUNTAINS
IN WESTERN COLORADO LATE IN THE 4TH AND 5TH PERIODS OF THE
FORECAST. WILL NEED TO WATCH SHOT OF WAA ON SUNDAY WHICH MAY SLOW
POTENTIAL SNOWFALL A BIT...BUT SERIES OF FAST MOVING PACIFIC WAVES
WILL EVENTUALLY SEND IN A LITTLE COOLER AIR ALOFT AND KEEP
SNOWFALL EFFICIENCY HIGH THROUGH EARLY MONDAY. NEW NAM IS A LITTLE
FAST...ADVERTISING A BREAK LATE MONDAY AND MONDAY NIGHT WITH THE
GFS A LITTLE SLOWER SHOWING SOME DRAG TO THE MOISTURE AND APPEARS
TO BE MORE REASONABLE BASED ON PREVIOUS EVENTS OF SIMILAR NATURE.

FLAT RIDGING SLIDES THROUGH TUESDAY AND WEDNESDAY AHEAD OF YET
ANOTHER POTENTIAL SYSTEM THAT IS EXPECTED TO ARRIVE BY CHRISTMAS
MORNING. THE GFS AND ECMWF CONTINUE TO JUMP AROUND FROM RUN TO RUN
WITH THE NEW ECMWF BACK TO SHOWING A CLOSED LOW MOVING OVER THE
FORECAST AREA ON CHRISTMAS. GFS HINTING AT MORE OF A SPLITTING
SYSTEM SENDING ENERGY NORTH AND SOUTH...WITH THE SOUTHERN SYSTEM
ROLLING ACROSS OUR FORECAST AREA. EITHER SCENARIO WOULD BRING
PRECIPITATION TO MUCH OF EASTERN UTAH AND WESTERN COLORADO...BUT
WITH SOME UNCERTAINTY STILL EVIDENT...WILL RUN WITH BLENDED POP
SOLUTIONS...WHICH OFFER SLIGHT CHANCE TO CHANCE POPS FOR NOW.
TEMPS COOL DOWN BEHIND THE CHRISTMAS SYSTEM.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 742 AM MST FRI DEC 19 2014

AREAS OF LIGHT SNOW WITH LOCAL FOG ARE EXPECTED MAINLY NORTH OF KCNY
TO KGUC LINE THIS MORNING RESULTING IN PERIODS OF MVFR CIGS AND
VSBYS AT KGJT...KRIL AND KEGE. MVFR CIGS WITH LOCAL IFR CIGS WERE
PREVALENT IN MANY VALLEYS ACROSS ERN UT AND WRN CO. VFR CONDITIONS
ARE EXPECTED AT TAF SITES THIS AFTERNOON WITH INCREASING MID AND
HIGH LEVEL MOISTURE BRINGING A GRADUALLY LOWERING OF CIGS AGAIN
TONIGHT.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR COZ008.

     WINTER STORM WATCH FROM LATE SATURDAY NIGHT THROUGH MONDAY
     AFTERNOON FOR COZ004-013.

     WINTER STORM WATCH FROM SUNDAY MORNING THROUGH MONDAY AFTERNOON
     FOR COZ005-010.

UT...NONE.
&&

$$

UPDATE...JAD
SHORT TERM...JAM
LONG TERM...JDC
AVIATION...JDC/JAD





000
FXUS65 KGJT 191528 CCA
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
827 AM MST FRI DEC 19 2014

CORRECTED UPDATED AVIATION SECTION TO REMOVE STRAY WORDS

.UPDATE...
ISSUED AT 742 AM MST FRI DEC 19 2014

A WEAK DISTURBANCE SEEN IN SATELLITE WATER VAPOR WAS CROSSING WRN
CO EARLY THIS MORNING GENERATING AREAS OF LIGHT SNOW IN A NEUTRAL
TO WEAKLY UNSTABLE ENVIRONMENT ALOFT PER THIS MORNINGS SOUNDING.
SNOW WILL GENERALLY BE JUST A DUSTING BUT ENOUGH TO BRING SOME
WHITENESS AT LEAST TEMPORARILY. AREAS OF FOG ALSO PRESENT THIS
MORNING. EXPECT THE MAJORITY OF THIS LIGHT SNOW TO END BY MIDDAY.
HAVE UPDATED GRIDDED FORECAST TO REFLECT CURRENT AND EXPECTED
CONDITIONS THIS MORNING.

&&

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 420 AM MST FRI DEC 19 2014

STILL HANGING ONTO A FEW ISOLATED SNOW SHOWERS ACROSS THE
BOOKCLIFFS AT MEEKER...SUNLIGHT...AND ASPEN THIS MORNING. FOG HAS
INTERMITTENTLY BEEN REDUCED TO A HALF MILE AT TIMES AT CRAIG THIS
MORNING BUT MOST LOCATIONS ARE STAYING OUT OF THE SOUP. WEAK
TRANSITORY RIDGING WILL BUILD INTO THE REGION TODAY...BUT BY THIS
EVENING MID TO HIGH LEVEL CLOUDS WILL BEGIN MOVING IN FROM THE
WEST. A FEW ISOLATED SHOWERS ARE POSSIBLE ON SATURDAY MORNING AHEAD
OF THE MAIN MOISTURE OVER NE UTAH AND NW COLORADO MOUNTAINS...BUT
THE MORE INTERESTING WEATHER IS IN THE FOLLOWING LONG TERM
SECTION.

.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 420 AM MST FRI DEC 19 2014

MOIST NORTHWEST FLOW WILL BE SETTLING IN OVER THE FORECAST AREA
SATURDAY NIGHT WITH A SLOW SOUTHWARD PROGRESSION INTO OUR CENTRAL
MOUNTAINS BY EARLY SUNDAY MORNING. STRONG UPPER LEVEL JET SLOPES
INTO THE AREA...PROVIDING DYNAMIC SUPPORT. MODELS REMAIN VERY
AGGRESSIVE WITH QPF VALUES WITH SNOWFALL ACCUMULATIONS EXCEEDING
A FOOT OVER A LARGE PORTION OF OUR NORTHERN AND CENTRAL MOUNTAINS
FROM VAIL NORTH TO THE WYOMING STATE LINE. FAVORED WEST AND
NORTHWEST SLOPES COULD EXCEED 2 FEET BY LATE MONDAY AS 30-40 KTS
H7 FLOW PROVIDES FAVORABLE OROGRAPHIC FLOW AND WORKS TO SQUEEZE
OUT ALL AVAILABLE MOISTURE ALONG AND WEST OF THE CONTINENTAL
DIVIDE. INITIAL SURGE FAVORS THE NORTHERN AND CENTRAL MOUNTAINS
BUT THE JET IS EXPECTED TO SAG SOUTH A BIT MORE THAN FORECAST AND
DRIVE MOISTURE SOUTHWARD INTO THE SAN JUANS BY SUNDAY
NIGHT...ALTHOUGH POTENTIAL SNOWFALL AMOUNTS WILL BE ABOUT HALF OF
WHAT WE CAN EXPECT OVER THE NORTH.

WITH HOLIDAY TRAVEL PICKING UP THIS WEEKEND...WE WENT AHEAD AND
ISSUED A WINTER STORM WATCH FOR THE NORTHERN AND CENTRAL MOUNTAINS
IN WESTERN COLORADO LATE IN THE 4TH AND 5TH PERIODS OF THE
FORECAST. WILL NEED TO WATCH SHOT OF WAA ON SUNDAY WHICH MAY SLOW
POTENTIAL SNOWFALL A BIT...BUT SERIES OF FAST MOVING PACIFIC WAVES
WILL EVENTUALLY SEND IN A LITTLE COOLER AIR ALOFT AND KEEP
SNOWFALL EFFICIENCY HIGH THROUGH EARLY MONDAY. NEW NAM IS A LITTLE
FAST...ADVERTISING A BREAK LATE MONDAY AND MONDAY NIGHT WITH THE
GFS A LITTLE SLOWER SHOWING SOME DRAG TO THE MOISTURE AND APPEARS
TO BE MORE REASONABLE BASED ON PREVIOUS EVENTS OF SIMILAR NATURE.

FLAT RIDGING SLIDES THROUGH TUESDAY AND WEDNESDAY AHEAD OF YET
ANOTHER POTENTIAL SYSTEM THAT IS EXPECTED TO ARRIVE BY CHRISTMAS
MORNING. THE GFS AND ECMWF CONTINUE TO JUMP AROUND FROM RUN TO RUN
WITH THE NEW ECMWF BACK TO SHOWING A CLOSED LOW MOVING OVER THE
FORECAST AREA ON CHRISTMAS. GFS HINTING AT MORE OF A SPLITTING
SYSTEM SENDING ENERGY NORTH AND SOUTH...WITH THE SOUTHERN SYSTEM
ROLLING ACROSS OUR FORECAST AREA. EITHER SCENARIO WOULD BRING
PRECIPITATION TO MUCH OF EASTERN UTAH AND WESTERN COLORADO...BUT
WITH SOME UNCERTAINTY STILL EVIDENT...WILL RUN WITH BLENDED POP
SOLUTIONS...WHICH OFFER SLIGHT CHANCE TO CHANCE POPS FOR NOW.
TEMPS COOL DOWN BEHIND THE CHRISTMAS SYSTEM.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 742 AM MST FRI DEC 19 2014

AREAS OF LIGHT SNOW WITH LOCAL FOG ARE EXPECTED MAINLY NORTH OF KCNY
TO KGUC LINE THIS MORNING RESULTING IN PERIODS OF MVFR CIGS AND
VSBYS AT KGJT...KRIL AND KEGE. MVFR CIGS WITH LOCAL IFR CIGS WERE
PREVALENT IN MANY VALLEYS ACROSS ERN UT AND WRN CO. VFR CONDITIONS
ARE EXPECTED AT TAF SITES THIS AFTERNOON WITH INCREASING MID AND
HIGH LEVEL MOISTURE BRINGING A GRADUALLY LOWERING OF CIGS AGAIN
TONIGHT.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR COZ008.

     WINTER STORM WATCH FROM LATE SATURDAY NIGHT THROUGH MONDAY
     AFTERNOON FOR COZ004-013.

     WINTER STORM WATCH FROM SUNDAY MORNING THROUGH MONDAY AFTERNOON
     FOR COZ005-010.

UT...NONE.
&&

$$

UPDATE...JAD
SHORT TERM...JAM
LONG TERM...JDC
AVIATION...JDC/JAD




000
FXUS65 KGJT 191458
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
758 AM MST FRI DEC 19 2014

.UPDATE...
ISSUED AT 742 AM MST FRI DEC 19 2014

A WEAK DISTURBANCE SEEN IN SATELLITE WATER VAPOR WAS CROSSING WRN
CO EARLY THIS MORNING GENERATING AREAS OF LIGHT SNOW IN A NEUTRAL
TO WEAKLY UNSTABLE ENVIRONMENT ALOFT PER THIS MORNINGS SOUNDING.
SNOW WILL GENERALLY BE JUST A DUSTING BUT ENOUGH TO BRING SOME
WHITENESS AT LEAST TEMPORARILY. AREAS OF FOG ALSO PRESENT THIS
MORNING. EXPECT THE MAJORITY OF THIS LIGHT SNOW TO END BY MIDDAY.
HAVE UPDATED GRIDDED FORECAST TO REFLECT CURRENT AND EXPECTED
CONDITIONS THIS MORNING.

&&

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 420 AM MST FRI DEC 19 2014

STILL HANGING ONTO A FEW ISOLATED SNOW SHOWERS ACROSS THE
BOOKCLIFFS AT MEEKER...SUNLIGHT...AND ASPEN THIS MORNING. FOG HAS
INTERMITTENTLY BEEN REDUCED TO A HALF MILE AT TIMES AT CRAIG THIS
MORNING BUT MOST LOCATIONS ARE STAYING OUT OF THE SOUP. WEAK
TRANSITORY RIDGING WILL BUILD INTO THE REGION TODAY...BUT BY THIS
EVENING MID TO HIGH LEVEL CLOUDS WILL BEGIN MOVING IN FROM THE
WEST. A FEW ISOLATED SHOWERS ARE POSSIBLE ON SATURDAY MORNING AHEAD
OF THE MAIN MOISTURE OVER NE UTAH AND NW COLORADO MOUNTAINS...BUT
THE MORE INTERESTING WEATHER IS IN THE FOLLOWING LONG TERM
SECTION.

.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 420 AM MST FRI DEC 19 2014

MOIST NORTHWEST FLOW WILL BE SETTLING IN OVER THE FORECAST AREA
SATURDAY NIGHT WITH A SLOW SOUTHWARD PROGRESSION INTO OUR CENTRAL
MOUNTAINS BY EARLY SUNDAY MORNING. STRONG UPPER LEVEL JET SLOPES
INTO THE AREA...PROVIDING DYNAMIC SUPPORT. MODELS REMAIN VERY
AGGRESSIVE WITH QPF VALUES WITH SNOWFALL ACCUMULATIONS EXCEEDING
A FOOT OVER A LARGE PORTION OF OUR NORTHERN AND CENTRAL MOUNTAINS
FROM VAIL NORTH TO THE WYOMING STATE LINE. FAVORED WEST AND
NORTHWEST SLOPES COULD EXCEED 2 FEET BY LATE MONDAY AS 30-40 KTS
H7 FLOW PROVIDES FAVORABLE OROGRAPHIC FLOW AND WORKS TO SQUEEZE
OUT ALL AVAILABLE MOISTURE ALONG AND WEST OF THE CONTINENTAL
DIVIDE. INITIAL SURGE FAVORS THE NORTHERN AND CENTRAL MOUNTAINS
BUT THE JET IS EXPECTED TO SAG SOUTH A BIT MORE THAN FORECAST AND
DRIVE MOISTURE SOUTHWARD INTO THE SAN JUANS BY SUNDAY
NIGHT...ALTHOUGH POTENTIAL SNOWFALL AMOUNTS WILL BE ABOUT HALF OF
WHAT WE CAN EXPECT OVER THE NORTH.

WITH HOLIDAY TRAVEL PICKING UP THIS WEEKEND...WE WENT AHEAD AND
ISSUED A WINTER STORM WATCH FOR THE NORTHERN AND CENTRAL MOUNTAINS
IN WESTERN COLORADO LATE IN THE 4TH AND 5TH PERIODS OF THE
FORECAST. WILL NEED TO WATCH SHOT OF WAA ON SUNDAY WHICH MAY SLOW
POTENTIAL SNOWFALL A BIT...BUT SERIES OF FAST MOVING PACIFIC WAVES
WILL EVENTUALLY SEND IN A LITTLE COOLER AIR ALOFT AND KEEP
SNOWFALL EFFICIENCY HIGH THROUGH EARLY MONDAY. NEW NAM IS A LITTLE
FAST...ADVERTISING A BREAK LATE MONDAY AND MONDAY NIGHT WITH THE
GFS A LITTLE SLOWER SHOWING SOME DRAG TO THE MOISTURE AND APPEARS
TO BE MORE REASONABLE BASED ON PREVIOUS EVENTS OF SIMILAR NATURE.

FLAT RIDGING SLIDES THROUGH TUESDAY AND WEDNESDAY AHEAD OF YET
ANOTHER POTENTIAL SYSTEM THAT IS EXPECTED TO ARRIVE BY CHRISTMAS
MORNING. THE GFS AND ECMWF CONTINUE TO JUMP AROUND FROM RUN TO RUN
WITH THE NEW ECMWF BACK TO SHOWING A CLOSED LOW MOVING OVER THE
FORECAST AREA ON CHRISTMAS. GFS HINTING AT MORE OF A SPLITTING
SYSTEM SENDING ENERGY NORTH AND SOUTH...WITH THE SOUTHERN SYSTEM
ROLLING ACROSS OUR FORECAST AREA. EITHER SCENARIO WOULD BRING
PRECIPITATION TO MUCH OF EASTERN UTAH AND WESTERN COLORADO...BUT
WITH SOME UNCERTAINTY STILL EVIDENT...WILL RUN WITH BLENDED POP
SOLUTIONS...WHICH OFFER SLIGHT CHANCE TO CHANCE POPS FOR NOW.
TEMPS COOL DOWN BEHIND THE CHRISTMAS SYSTEM.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 742 AM MST FRI DEC 19 2014

AREAS OF LIGHT SNOW ALONG THE INTERSTATE 70 CORRIDOR WILL PERSIST
THIS MORNING RESULTING IN KMVFR

AREAS OF LIGHT SNOW WITH LOCAL FOG ARE EXPECTED MAINLY NORTH OF
KCNY TO KGUC LINE THIS MORNING RESULTING IN PERIODS OF MVFR CIGS
AND VSBYS AT KGJT...KRIL AND KEGE. MVFR CIGS WITH LOCAL IFR CIGS WERE
PREVALENT MANY VALLEYS ACROSS ERN UT AND WRN CO. VFR CONDITIONS
ARE EXPECTED AT TAF SITES THIS AFTERNOON TO PREVAIL TODAY WITH
INCREASING MID AND HIGH LEVEL MOISTURE BRINGING A GRADUALLY
LOWERING OF CIGS AGAIN TONIGHT.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR COZ008.

     WINTER STORM WATCH FROM LATE SATURDAY NIGHT THROUGH MONDAY
     AFTERNOON FOR COZ004-013.

     WINTER STORM WATCH FROM SUNDAY MORNING THROUGH MONDAY AFTERNOON
     FOR COZ005-010.

UT...NONE.
&&

$$

UPDATE...JAD
SHORT TERM...JAM
LONG TERM...JDC
AVIATION...JDC/JAD




000
FXUS65 KGJT 191458
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
758 AM MST FRI DEC 19 2014

.UPDATE...
ISSUED AT 742 AM MST FRI DEC 19 2014

A WEAK DISTURBANCE SEEN IN SATELLITE WATER VAPOR WAS CROSSING WRN
CO EARLY THIS MORNING GENERATING AREAS OF LIGHT SNOW IN A NEUTRAL
TO WEAKLY UNSTABLE ENVIRONMENT ALOFT PER THIS MORNINGS SOUNDING.
SNOW WILL GENERALLY BE JUST A DUSTING BUT ENOUGH TO BRING SOME
WHITENESS AT LEAST TEMPORARILY. AREAS OF FOG ALSO PRESENT THIS
MORNING. EXPECT THE MAJORITY OF THIS LIGHT SNOW TO END BY MIDDAY.
HAVE UPDATED GRIDDED FORECAST TO REFLECT CURRENT AND EXPECTED
CONDITIONS THIS MORNING.

&&

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 420 AM MST FRI DEC 19 2014

STILL HANGING ONTO A FEW ISOLATED SNOW SHOWERS ACROSS THE
BOOKCLIFFS AT MEEKER...SUNLIGHT...AND ASPEN THIS MORNING. FOG HAS
INTERMITTENTLY BEEN REDUCED TO A HALF MILE AT TIMES AT CRAIG THIS
MORNING BUT MOST LOCATIONS ARE STAYING OUT OF THE SOUP. WEAK
TRANSITORY RIDGING WILL BUILD INTO THE REGION TODAY...BUT BY THIS
EVENING MID TO HIGH LEVEL CLOUDS WILL BEGIN MOVING IN FROM THE
WEST. A FEW ISOLATED SHOWERS ARE POSSIBLE ON SATURDAY MORNING AHEAD
OF THE MAIN MOISTURE OVER NE UTAH AND NW COLORADO MOUNTAINS...BUT
THE MORE INTERESTING WEATHER IS IN THE FOLLOWING LONG TERM
SECTION.

.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 420 AM MST FRI DEC 19 2014

MOIST NORTHWEST FLOW WILL BE SETTLING IN OVER THE FORECAST AREA
SATURDAY NIGHT WITH A SLOW SOUTHWARD PROGRESSION INTO OUR CENTRAL
MOUNTAINS BY EARLY SUNDAY MORNING. STRONG UPPER LEVEL JET SLOPES
INTO THE AREA...PROVIDING DYNAMIC SUPPORT. MODELS REMAIN VERY
AGGRESSIVE WITH QPF VALUES WITH SNOWFALL ACCUMULATIONS EXCEEDING
A FOOT OVER A LARGE PORTION OF OUR NORTHERN AND CENTRAL MOUNTAINS
FROM VAIL NORTH TO THE WYOMING STATE LINE. FAVORED WEST AND
NORTHWEST SLOPES COULD EXCEED 2 FEET BY LATE MONDAY AS 30-40 KTS
H7 FLOW PROVIDES FAVORABLE OROGRAPHIC FLOW AND WORKS TO SQUEEZE
OUT ALL AVAILABLE MOISTURE ALONG AND WEST OF THE CONTINENTAL
DIVIDE. INITIAL SURGE FAVORS THE NORTHERN AND CENTRAL MOUNTAINS
BUT THE JET IS EXPECTED TO SAG SOUTH A BIT MORE THAN FORECAST AND
DRIVE MOISTURE SOUTHWARD INTO THE SAN JUANS BY SUNDAY
NIGHT...ALTHOUGH POTENTIAL SNOWFALL AMOUNTS WILL BE ABOUT HALF OF
WHAT WE CAN EXPECT OVER THE NORTH.

WITH HOLIDAY TRAVEL PICKING UP THIS WEEKEND...WE WENT AHEAD AND
ISSUED A WINTER STORM WATCH FOR THE NORTHERN AND CENTRAL MOUNTAINS
IN WESTERN COLORADO LATE IN THE 4TH AND 5TH PERIODS OF THE
FORECAST. WILL NEED TO WATCH SHOT OF WAA ON SUNDAY WHICH MAY SLOW
POTENTIAL SNOWFALL A BIT...BUT SERIES OF FAST MOVING PACIFIC WAVES
WILL EVENTUALLY SEND IN A LITTLE COOLER AIR ALOFT AND KEEP
SNOWFALL EFFICIENCY HIGH THROUGH EARLY MONDAY. NEW NAM IS A LITTLE
FAST...ADVERTISING A BREAK LATE MONDAY AND MONDAY NIGHT WITH THE
GFS A LITTLE SLOWER SHOWING SOME DRAG TO THE MOISTURE AND APPEARS
TO BE MORE REASONABLE BASED ON PREVIOUS EVENTS OF SIMILAR NATURE.

FLAT RIDGING SLIDES THROUGH TUESDAY AND WEDNESDAY AHEAD OF YET
ANOTHER POTENTIAL SYSTEM THAT IS EXPECTED TO ARRIVE BY CHRISTMAS
MORNING. THE GFS AND ECMWF CONTINUE TO JUMP AROUND FROM RUN TO RUN
WITH THE NEW ECMWF BACK TO SHOWING A CLOSED LOW MOVING OVER THE
FORECAST AREA ON CHRISTMAS. GFS HINTING AT MORE OF A SPLITTING
SYSTEM SENDING ENERGY NORTH AND SOUTH...WITH THE SOUTHERN SYSTEM
ROLLING ACROSS OUR FORECAST AREA. EITHER SCENARIO WOULD BRING
PRECIPITATION TO MUCH OF EASTERN UTAH AND WESTERN COLORADO...BUT
WITH SOME UNCERTAINTY STILL EVIDENT...WILL RUN WITH BLENDED POP
SOLUTIONS...WHICH OFFER SLIGHT CHANCE TO CHANCE POPS FOR NOW.
TEMPS COOL DOWN BEHIND THE CHRISTMAS SYSTEM.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 742 AM MST FRI DEC 19 2014

AREAS OF LIGHT SNOW ALONG THE INTERSTATE 70 CORRIDOR WILL PERSIST
THIS MORNING RESULTING IN KMVFR

AREAS OF LIGHT SNOW WITH LOCAL FOG ARE EXPECTED MAINLY NORTH OF
KCNY TO KGUC LINE THIS MORNING RESULTING IN PERIODS OF MVFR CIGS
AND VSBYS AT KGJT...KRIL AND KEGE. MVFR CIGS WITH LOCAL IFR CIGS WERE
PREVALENT MANY VALLEYS ACROSS ERN UT AND WRN CO. VFR CONDITIONS
ARE EXPECTED AT TAF SITES THIS AFTERNOON TO PREVAIL TODAY WITH
INCREASING MID AND HIGH LEVEL MOISTURE BRINGING A GRADUALLY
LOWERING OF CIGS AGAIN TONIGHT.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR COZ008.

     WINTER STORM WATCH FROM LATE SATURDAY NIGHT THROUGH MONDAY
     AFTERNOON FOR COZ004-013.

     WINTER STORM WATCH FROM SUNDAY MORNING THROUGH MONDAY AFTERNOON
     FOR COZ005-010.

UT...NONE.
&&

$$

UPDATE...JAD
SHORT TERM...JAM
LONG TERM...JDC
AVIATION...JDC/JAD





000
FXUS65 KGJT 191121
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
421 AM MST FRI DEC 19 2014

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 420 AM MST FRI DEC 19 2014

STILL HANGING ONTO A FEW ISOLATED SNOW SHOWERS ACROSS THE
BOOKCLIFFS AT MEEKER...SUNLIGHT...AND ASPEN THIS MORNING. FOG HAS
INTERMITTENTLY BEEN REDUCED TO A HALF MILE AT TIMES AT CRAIG THIS
MORNING BUT MOST LOCATIONS ARE STAYING OUT OF THE SOUP. WEAK
TRANSITORY RIDGING WILL BUILD INTO THE REGION TODAY...BUT BY THIS
EVENING MID TO HIGH LEVEL CLOUDS WILL BEGIN MOVING IN FROM THE
WEST. A FEW ISOLATED SHOWERS ARE POSSIBLE ON SATURDAY MORNING AHEAD
OF THE MAIN MOISTURE OVER NE UTAH AND NW COLORADO MOUNTAINS...BUT
THE MORE INTERESTING WEATHER IS IN THE FOLLOWING LONG TERM
SECTION.

.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 420 AM MST FRI DEC 19 2014

MOIST NORTHWEST FLOW WILL BE SETTLING IN OVER THE FORECAST AREA
SATURDAY NIGHT WITH A SLOW SOUTHWARD PROGRESSION INTO OUR CENTRAL
MOUNTAINS BY EARLY SUNDAY MORNING. STRONG UPPER LEVEL JET SLOPES
INTO THE AREA...PROVIDING DYNAMIC SUPPORT. MODELS REMAIN VERY
AGGRESSIVE WITH QPF VALUES WITH SNOWFALL ACCUMULATIONS EXCEEDING
A FOOT OVER A LARGE PORTION OF OUR NORTHERN AND CENTRAL MOUNTAINS
FROM VAIL NORTH TO THE WYOMING STATE LINE. FAVORED WEST AND
NORTHWEST SLOPES COULD EXCEED 2 FEET BY LATE MONDAY AS 30-40 KTS
H7 FLOW PROVIDES FAVORABLE OROGRAPHIC FLOW AND WORKS TO SQUEEZE
OUT ALL AVAILABLE MOISTURE ALONG AND WEST OF THE CONTINENTAL
DIVIDE. INITIAL SURGE FAVORS THE NORTHERN AND CENTRAL MOUNTAINS
BUT THE JET IS EXPECTED TO SAG SOUTH A BIT MORE THAN FORECAST AND
DRIVE MOISTURE SOUTHWARD INTO THE SAN JUANS BY SUNDAY
NIGHT...ALTHOUGH POTENTIAL SNOWFALL AMOUNTS WILL BE ABOUT HALF OF
WHAT WE CAN EXPECT OVER THE NORTH.

WITH HOLIDAY TRAVEL PICKING UP THIS WEEKEND...WE WENT AHEAD AND
ISSUED A WINTER STORM WATCH FOR THE NORTHERN AND CENTRAL MOUNTAINS
IN WESTERN COLORADO LATE IN THE 4TH AND 5TH PERIODS OF THE
FORECAST. WILL NEED TO WATCH SHOT OF WAA ON SUNDAY WHICH MAY SLOW
POTENTIAL SNOWFALL A BIT...BUT SERIES OF FAST MOVING PACIFIC WAVES
WILL EVENTUALLY SEND IN A LITTLE COOLER AIR ALOFT AND KEEP
SNOWFALL EFFICIENCY HIGH THROUGH EARLY MONDAY. NEW NAM IS A LITTLE
FAST...ADVERTISING A BREAK LATE MONDAY AND MONDAY NIGHT WITH THE
GFS A LITTLE SLOWER SHOWING SOME DRAG TO THE MOISTURE AND APPEARS
TO BE MORE REASONABLE BASED ON PREVIOUS EVENTS OF SIMILAR NATURE.

FLAT RIDGING SLIDES THROUGH TUESDAY AND WEDNESDAY AHEAD OF YET
ANOTHER POTENTIAL SYSTEM THAT IS EXPECTED TO ARRIVE BY CHRISTMAS
MORNING. THE GFS AND ECMWF CONTINUE TO JUMP AROUND FROM RUN TO RUN
WITH THE NEW ECMWF BACK TO SHOWING A CLOSED LOW MOVING OVER THE
FORECAST AREA ON CHRISTMAS. GFS HINTING AT MORE OF A SPLITTING
SYSTEM SENDING ENERGY NORTH AND SOUTH...WITH THE SOUTHERN SYSTEM
ROLLING ACROSS OUR FORECAST AREA. EITHER SCENARIO WOULD BRING
PRECIPITATION TO MUCH OF EASTERN UTAH AND WESTERN COLORADO...BUT
WITH SOME UNCERTAINTY STILL EVIDENT...WILL RUN WITH BLENDED POP
SOLUTIONS...WHICH OFFER SLIGHT CHANCE TO CHANCE POPS FOR NOW.
TEMPS COOL DOWN BEHIND THE CHRISTMAS SYSTEM.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 420 AM MST FRI DEC 19 2014

ISOLATED SNOW SHOWERS CAN BE EXPECTED NORTH OF A LINE FROM KGJT TO
KASE TODAY WITH LOCAL MVFR CIGS AND VSBYS IN THE VICINITY OF THE
SHOWERS. POTENTIAL IMPACT ON ANY TERMINAL SITES WILL BE LESS THAN
20 PERCENT WITH KRIL...KEGE AND KASE POSSIBLY IMPACTED.
OTHERWISE...VFR CONDITIONS EXPECTED TO PREVAIL TODAY WITH
INCREASING MID AND HIGH LEVEL MOISTURE BRINGING A GRADUALLY
LOWERING OF CIGS LATE TODAY AND TONIGHT.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR COZ008.

     WINTER STORM WATCH FROM LATE SATURDAY NIGHT THROUGH MONDAY
     AFTERNOON FOR COZ004-013.

     WINTER STORM WATCH FROM SUNDAY MORNING THROUGH MONDAY AFTERNOON
     FOR COZ005-010.

UT...NONE.
&&

$$

SHORT TERM...JAM
LONG TERM...JDC
AVIATION...JDC




000
FXUS65 KGJT 191121
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
421 AM MST FRI DEC 19 2014

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 420 AM MST FRI DEC 19 2014

STILL HANGING ONTO A FEW ISOLATED SNOW SHOWERS ACROSS THE
BOOKCLIFFS AT MEEKER...SUNLIGHT...AND ASPEN THIS MORNING. FOG HAS
INTERMITTENTLY BEEN REDUCED TO A HALF MILE AT TIMES AT CRAIG THIS
MORNING BUT MOST LOCATIONS ARE STAYING OUT OF THE SOUP. WEAK
TRANSITORY RIDGING WILL BUILD INTO THE REGION TODAY...BUT BY THIS
EVENING MID TO HIGH LEVEL CLOUDS WILL BEGIN MOVING IN FROM THE
WEST. A FEW ISOLATED SHOWERS ARE POSSIBLE ON SATURDAY MORNING AHEAD
OF THE MAIN MOISTURE OVER NE UTAH AND NW COLORADO MOUNTAINS...BUT
THE MORE INTERESTING WEATHER IS IN THE FOLLOWING LONG TERM
SECTION.

.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 420 AM MST FRI DEC 19 2014

MOIST NORTHWEST FLOW WILL BE SETTLING IN OVER THE FORECAST AREA
SATURDAY NIGHT WITH A SLOW SOUTHWARD PROGRESSION INTO OUR CENTRAL
MOUNTAINS BY EARLY SUNDAY MORNING. STRONG UPPER LEVEL JET SLOPES
INTO THE AREA...PROVIDING DYNAMIC SUPPORT. MODELS REMAIN VERY
AGGRESSIVE WITH QPF VALUES WITH SNOWFALL ACCUMULATIONS EXCEEDING
A FOOT OVER A LARGE PORTION OF OUR NORTHERN AND CENTRAL MOUNTAINS
FROM VAIL NORTH TO THE WYOMING STATE LINE. FAVORED WEST AND
NORTHWEST SLOPES COULD EXCEED 2 FEET BY LATE MONDAY AS 30-40 KTS
H7 FLOW PROVIDES FAVORABLE OROGRAPHIC FLOW AND WORKS TO SQUEEZE
OUT ALL AVAILABLE MOISTURE ALONG AND WEST OF THE CONTINENTAL
DIVIDE. INITIAL SURGE FAVORS THE NORTHERN AND CENTRAL MOUNTAINS
BUT THE JET IS EXPECTED TO SAG SOUTH A BIT MORE THAN FORECAST AND
DRIVE MOISTURE SOUTHWARD INTO THE SAN JUANS BY SUNDAY
NIGHT...ALTHOUGH POTENTIAL SNOWFALL AMOUNTS WILL BE ABOUT HALF OF
WHAT WE CAN EXPECT OVER THE NORTH.

WITH HOLIDAY TRAVEL PICKING UP THIS WEEKEND...WE WENT AHEAD AND
ISSUED A WINTER STORM WATCH FOR THE NORTHERN AND CENTRAL MOUNTAINS
IN WESTERN COLORADO LATE IN THE 4TH AND 5TH PERIODS OF THE
FORECAST. WILL NEED TO WATCH SHOT OF WAA ON SUNDAY WHICH MAY SLOW
POTENTIAL SNOWFALL A BIT...BUT SERIES OF FAST MOVING PACIFIC WAVES
WILL EVENTUALLY SEND IN A LITTLE COOLER AIR ALOFT AND KEEP
SNOWFALL EFFICIENCY HIGH THROUGH EARLY MONDAY. NEW NAM IS A LITTLE
FAST...ADVERTISING A BREAK LATE MONDAY AND MONDAY NIGHT WITH THE
GFS A LITTLE SLOWER SHOWING SOME DRAG TO THE MOISTURE AND APPEARS
TO BE MORE REASONABLE BASED ON PREVIOUS EVENTS OF SIMILAR NATURE.

FLAT RIDGING SLIDES THROUGH TUESDAY AND WEDNESDAY AHEAD OF YET
ANOTHER POTENTIAL SYSTEM THAT IS EXPECTED TO ARRIVE BY CHRISTMAS
MORNING. THE GFS AND ECMWF CONTINUE TO JUMP AROUND FROM RUN TO RUN
WITH THE NEW ECMWF BACK TO SHOWING A CLOSED LOW MOVING OVER THE
FORECAST AREA ON CHRISTMAS. GFS HINTING AT MORE OF A SPLITTING
SYSTEM SENDING ENERGY NORTH AND SOUTH...WITH THE SOUTHERN SYSTEM
ROLLING ACROSS OUR FORECAST AREA. EITHER SCENARIO WOULD BRING
PRECIPITATION TO MUCH OF EASTERN UTAH AND WESTERN COLORADO...BUT
WITH SOME UNCERTAINTY STILL EVIDENT...WILL RUN WITH BLENDED POP
SOLUTIONS...WHICH OFFER SLIGHT CHANCE TO CHANCE POPS FOR NOW.
TEMPS COOL DOWN BEHIND THE CHRISTMAS SYSTEM.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 420 AM MST FRI DEC 19 2014

ISOLATED SNOW SHOWERS CAN BE EXPECTED NORTH OF A LINE FROM KGJT TO
KASE TODAY WITH LOCAL MVFR CIGS AND VSBYS IN THE VICINITY OF THE
SHOWERS. POTENTIAL IMPACT ON ANY TERMINAL SITES WILL BE LESS THAN
20 PERCENT WITH KRIL...KEGE AND KASE POSSIBLY IMPACTED.
OTHERWISE...VFR CONDITIONS EXPECTED TO PREVAIL TODAY WITH
INCREASING MID AND HIGH LEVEL MOISTURE BRINGING A GRADUALLY
LOWERING OF CIGS LATE TODAY AND TONIGHT.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR COZ008.

     WINTER STORM WATCH FROM LATE SATURDAY NIGHT THROUGH MONDAY
     AFTERNOON FOR COZ004-013.

     WINTER STORM WATCH FROM SUNDAY MORNING THROUGH MONDAY AFTERNOON
     FOR COZ005-010.

UT...NONE.
&&

$$

SHORT TERM...JAM
LONG TERM...JDC
AVIATION...JDC





000
FXUS65 KGJT 190906
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
206 AM MST FRI DEC 19 2014

.UPDATE...
ISSUED AT 203 AM MST FRI DEC 19 2014

A FEW HIGH CLOUDS ARE MOVING EAST INTO THE FORECAST REGION...WHICH
ARE HELPING TO KEEP STEEP INVERSIONS FROM DEVELOPING IN THE
VALLEYS. DECIDED TO END THE DENSE FOG ADVISORY EARLY IN
ANTIPICATION OF VISIBILITIES REMAINING ABOVE ONE QUARTER MILE FOR
THE REST OF THE MORNING.

&&

.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 332 PM MST THU DEC 18 2014

THE ATMOSPHERE SEEMS TO BE VERY EFFICIENT IN MAKING SNOW TODAY
ESPECIALLY WITH A BIT OF INSTABILITY ADDED TO THE MIX. IMPACTS TO
ROADWAYS SEEN ON WEBCAMS AROUND THE REGION ARE MINIMAL BUT THERE
COULD BE SOME SNOW PACKED AND ICY SPOTS ON NORTH FACING SLOPES.
THIS IS LIKELY ON THE MESA WHERE THE BEST SNOW HAS FALLEN SINCE
MID MORNING. THE WAVE ADDING ASCENT WILL BE MOVING OVER WESTERN
COLORADO THIS EVENING AND SHOULD KEEP SOME TERRAIN BASED SHOWERS
GOING THROUGH MIDNIGHT...WITH NORTH/WEST FACING SLOPES FAVORED
LOOKING AT THE MID LEVEL FLOW. FROM SUNRISE INTO MID MORNING A FEW
SHOWERS MAY LINGER OVER THE NORTHERN MOUNTAINS...BUT AS TRANSITORY
RIDGING BRINGS IN WAA ALOFT DURING THE AFTERNOON...THE MORE STABLE
CONDITIONS SHOULD SHUT OFF MOST OF THE SHOWERS BY EARLY AFTERNOON.
THIS RIDGING REMAINS IN PLACE THROUGH EARLY SATURDAY BEFORE
UPSTREAM ENERGY PUSHES THE RIDGE AXIS TO THE HIGH PLAINS AND THE
FLOW TURNS MORE NORTHWESTERLY AND PROGRESSIVELY MORE MOIST.
TEMPERATURES UNDER THE RIDGE WILL STRUGGLE DUE TO RECENT SNOWFALL
AND PRECIPITATION...SO HIGHS NEAR OR SLIGHTLY BELOW NORMAL ARE IN
PLACE. THE BIGGER CHALLENGE TO THE FORECAST WILL BE LINGERING PBL
MOISTURE AND DRYING ALOFT TONIGHT. FOG WAS FAIRLY COMMON OVERNIGHT
AND THIS WILL BE THE CASE AGAIN OVERNIGHT. THERE WILL BE AREAS OF
DENSE FOG ALONG SOME VALLEY LOCATIONS BUT CONFIDENCE TOO LOW ATTM
TO HOIST ADVISORIES.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 332 PM MST THU DEC 18 2014

..SIGNIFICANT MOUNTAIN SNOWFALL POSSIBLE LATE THIS WEEKEND AND
EARLY NEXT WEEK. ANOTHER STORM POSSIBLE ON CHRISTMAS DAY...

MODELS CONTINUE TO POINT TOWARD AN EXTENDED PERIOD OF UNSETTLED
WEATHER THROUGH NEXT WEEK. THE PERSISTENT LONGWAVE RIDGE OVER THE
WESTERN STATES FLATTENS THIS WEEKEND AND THEN REBUILDS FARTHER TO
THE WEST OVER THE NORTHEASTERN PACIFIC OCEAN. THIS WILL FAVOR A MORE
CONSOLIDATED NORTHWEST FLOW OVER OUR AREA FOR MUCH OF NEXT WEEK WITH
A GENERALY COOLING IN TEMPERATURES...VERSUS THE SPLIT FLOW PATTERN
OF THE RECENT PAST.

ONE SHORTWAVE DISTURBANCE CROSSES ON SAT AND HELPS TO FLATTEN THE
RIDGE WHILE BRINGING A CHANCE OF LIGHT SNOW TO THE NORTHERN AND
PERHAPS CENTRAL MTNS.

A STRONG AND MOIST JET STREAM BLASTS INTO THE PACIFIC NORTHWEST THIS
WEEKEND AND ACROSS WY ON SUNDAY. THIS 120-130KT JET THEN BECOMES
ORIENTED NORTHWEST TO SOUTHEAST OVER CO MONDAY-MONDAY NIGHT AS THE
UPPER RIDGE BEGINS TO AMPLIFY OVER THE NERN PACIFIC. ABUNDANT
MOISTURE COMBINED WITH JET DYNAMICS AND OROGRAPHIC FORCING SHOULD
RESULT IN AN EXTENDED PERIOD OF SNOW FOR THE NORTHERN AND CENTRAL CO
MTNS SUNDAY AFTERNOON THROUGH MONDAY NIGHT. SCATTERED SNOW SHOWERS
WILL PERSIST ACROSS THE NRN MTNS TO VAIL TUE IN NW FLOW WHILE SNOW
DECREASES ELSEWHERE AS THE UPPER JET SLIPS EASTWARD. WINDY
CONDITIONS ARE LIKELY CREATING AREAS OF BLOWING SNOW AS WELL. TRAVEL
OVER THE RABBIT EARS AND VAIL PASSES LATE SUNDAY INTO TUESDAY WILL
BE NEGATIVELY IMPACTED AND WILL CONTINUE WITH THE SPECIAL WEATHER
STATEMENT ADDRESSING THIS.  BUT AS STATED IN THE EARLIER
DISCUSSION...WARM ADVECTION SUNDAY AFTERNOON/ EVENING MAY RESULT IN
LESSER SNOW AMTS INITIALLY BEFORE COLDER AIR SETTLES IN MONDAY AS
THE JET MOVES OVERHEAD.

MODELS INDICATE A BIT OF A BREAK LATE TUESDAY INTO WEDNESDAY AS A
TRANSITORY RIDGE MOVES ACROSS AHEAD OF THE NEXT TROUGH EXPECTED TO
ENTER THE PACIFIC NORTHWEST. 12Z ECWMF AND 12Z GFS NOW IN BETTER
AGREEMENT ON BRING THIS TROUGH ACROSS OUR AREA ON CHRISTMAS DAY FOR
A CHANCE OF SNOW. THIS IS A RATHER SIGNIFICANT CHANGE FOR THE ECWMF
WHICH HAD BEEN SHOWING THE TROUGH CLOSING OFF A MID-LEVEL LOW OVER
THE GREAT BASIN THU. WILL SEE IF THIS MODEL AGREEMENT CONTINUES.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1029 PM MST THU DEC 18 2014

BIGGEST CHALLENGE OF THE NIGHT WILL BE VISIBILITIES. ALREADY
SEEING DENSE FOG AT KCAG AND KSBS WITH K5SM NOT FAR BEHIND AT A
HALF MILE VIS. EXPECTING DENSE FOG TO BE INTERMITTENT THROUGHOUT
THE NIGHT AND NOT WIDESPREAD ACROSS WESTERN CO/EASTERN UT.

WIDESPREAD VFR EXPECTED ON FRIDAY...WITH HIGH CLOUDS INCREASING
FROM WEST TO EAST AFTER 23Z.


&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.

UT...NONE.
&&

$$

UPDATE...JAM
SHORT TERM...15
LONG TERM...JAD
AVIATION...JAM




000
FXUS65 KGJT 190906
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
206 AM MST FRI DEC 19 2014

.UPDATE...
ISSUED AT 203 AM MST FRI DEC 19 2014

A FEW HIGH CLOUDS ARE MOVING EAST INTO THE FORECAST REGION...WHICH
ARE HELPING TO KEEP STEEP INVERSIONS FROM DEVELOPING IN THE
VALLEYS. DECIDED TO END THE DENSE FOG ADVISORY EARLY IN
ANTIPICATION OF VISIBILITIES REMAINING ABOVE ONE QUARTER MILE FOR
THE REST OF THE MORNING.

&&

.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 332 PM MST THU DEC 18 2014

THE ATMOSPHERE SEEMS TO BE VERY EFFICIENT IN MAKING SNOW TODAY
ESPECIALLY WITH A BIT OF INSTABILITY ADDED TO THE MIX. IMPACTS TO
ROADWAYS SEEN ON WEBCAMS AROUND THE REGION ARE MINIMAL BUT THERE
COULD BE SOME SNOW PACKED AND ICY SPOTS ON NORTH FACING SLOPES.
THIS IS LIKELY ON THE MESA WHERE THE BEST SNOW HAS FALLEN SINCE
MID MORNING. THE WAVE ADDING ASCENT WILL BE MOVING OVER WESTERN
COLORADO THIS EVENING AND SHOULD KEEP SOME TERRAIN BASED SHOWERS
GOING THROUGH MIDNIGHT...WITH NORTH/WEST FACING SLOPES FAVORED
LOOKING AT THE MID LEVEL FLOW. FROM SUNRISE INTO MID MORNING A FEW
SHOWERS MAY LINGER OVER THE NORTHERN MOUNTAINS...BUT AS TRANSITORY
RIDGING BRINGS IN WAA ALOFT DURING THE AFTERNOON...THE MORE STABLE
CONDITIONS SHOULD SHUT OFF MOST OF THE SHOWERS BY EARLY AFTERNOON.
THIS RIDGING REMAINS IN PLACE THROUGH EARLY SATURDAY BEFORE
UPSTREAM ENERGY PUSHES THE RIDGE AXIS TO THE HIGH PLAINS AND THE
FLOW TURNS MORE NORTHWESTERLY AND PROGRESSIVELY MORE MOIST.
TEMPERATURES UNDER THE RIDGE WILL STRUGGLE DUE TO RECENT SNOWFALL
AND PRECIPITATION...SO HIGHS NEAR OR SLIGHTLY BELOW NORMAL ARE IN
PLACE. THE BIGGER CHALLENGE TO THE FORECAST WILL BE LINGERING PBL
MOISTURE AND DRYING ALOFT TONIGHT. FOG WAS FAIRLY COMMON OVERNIGHT
AND THIS WILL BE THE CASE AGAIN OVERNIGHT. THERE WILL BE AREAS OF
DENSE FOG ALONG SOME VALLEY LOCATIONS BUT CONFIDENCE TOO LOW ATTM
TO HOIST ADVISORIES.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 332 PM MST THU DEC 18 2014

..SIGNIFICANT MOUNTAIN SNOWFALL POSSIBLE LATE THIS WEEKEND AND
EARLY NEXT WEEK. ANOTHER STORM POSSIBLE ON CHRISTMAS DAY...

MODELS CONTINUE TO POINT TOWARD AN EXTENDED PERIOD OF UNSETTLED
WEATHER THROUGH NEXT WEEK. THE PERSISTENT LONGWAVE RIDGE OVER THE
WESTERN STATES FLATTENS THIS WEEKEND AND THEN REBUILDS FARTHER TO
THE WEST OVER THE NORTHEASTERN PACIFIC OCEAN. THIS WILL FAVOR A MORE
CONSOLIDATED NORTHWEST FLOW OVER OUR AREA FOR MUCH OF NEXT WEEK WITH
A GENERALY COOLING IN TEMPERATURES...VERSUS THE SPLIT FLOW PATTERN
OF THE RECENT PAST.

ONE SHORTWAVE DISTURBANCE CROSSES ON SAT AND HELPS TO FLATTEN THE
RIDGE WHILE BRINGING A CHANCE OF LIGHT SNOW TO THE NORTHERN AND
PERHAPS CENTRAL MTNS.

A STRONG AND MOIST JET STREAM BLASTS INTO THE PACIFIC NORTHWEST THIS
WEEKEND AND ACROSS WY ON SUNDAY. THIS 120-130KT JET THEN BECOMES
ORIENTED NORTHWEST TO SOUTHEAST OVER CO MONDAY-MONDAY NIGHT AS THE
UPPER RIDGE BEGINS TO AMPLIFY OVER THE NERN PACIFIC. ABUNDANT
MOISTURE COMBINED WITH JET DYNAMICS AND OROGRAPHIC FORCING SHOULD
RESULT IN AN EXTENDED PERIOD OF SNOW FOR THE NORTHERN AND CENTRAL CO
MTNS SUNDAY AFTERNOON THROUGH MONDAY NIGHT. SCATTERED SNOW SHOWERS
WILL PERSIST ACROSS THE NRN MTNS TO VAIL TUE IN NW FLOW WHILE SNOW
DECREASES ELSEWHERE AS THE UPPER JET SLIPS EASTWARD. WINDY
CONDITIONS ARE LIKELY CREATING AREAS OF BLOWING SNOW AS WELL. TRAVEL
OVER THE RABBIT EARS AND VAIL PASSES LATE SUNDAY INTO TUESDAY WILL
BE NEGATIVELY IMPACTED AND WILL CONTINUE WITH THE SPECIAL WEATHER
STATEMENT ADDRESSING THIS.  BUT AS STATED IN THE EARLIER
DISCUSSION...WARM ADVECTION SUNDAY AFTERNOON/ EVENING MAY RESULT IN
LESSER SNOW AMTS INITIALLY BEFORE COLDER AIR SETTLES IN MONDAY AS
THE JET MOVES OVERHEAD.

MODELS INDICATE A BIT OF A BREAK LATE TUESDAY INTO WEDNESDAY AS A
TRANSITORY RIDGE MOVES ACROSS AHEAD OF THE NEXT TROUGH EXPECTED TO
ENTER THE PACIFIC NORTHWEST. 12Z ECWMF AND 12Z GFS NOW IN BETTER
AGREEMENT ON BRING THIS TROUGH ACROSS OUR AREA ON CHRISTMAS DAY FOR
A CHANCE OF SNOW. THIS IS A RATHER SIGNIFICANT CHANGE FOR THE ECWMF
WHICH HAD BEEN SHOWING THE TROUGH CLOSING OFF A MID-LEVEL LOW OVER
THE GREAT BASIN THU. WILL SEE IF THIS MODEL AGREEMENT CONTINUES.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1029 PM MST THU DEC 18 2014

BIGGEST CHALLENGE OF THE NIGHT WILL BE VISIBILITIES. ALREADY
SEEING DENSE FOG AT KCAG AND KSBS WITH K5SM NOT FAR BEHIND AT A
HALF MILE VIS. EXPECTING DENSE FOG TO BE INTERMITTENT THROUGHOUT
THE NIGHT AND NOT WIDESPREAD ACROSS WESTERN CO/EASTERN UT.

WIDESPREAD VFR EXPECTED ON FRIDAY...WITH HIGH CLOUDS INCREASING
FROM WEST TO EAST AFTER 23Z.


&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.

UT...NONE.
&&

$$

UPDATE...JAM
SHORT TERM...15
LONG TERM...JAD
AVIATION...JAM





000
FXUS65 KGJT 190538
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1038 PM MST THU DEC 18 2014

.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 332 PM MST THU DEC 18 2014

THE ATMOSPHERE SEEMS TO BE VERY EFFICIENT IN MAKING SNOW TODAY
ESPECIALLY WITH A BIT OF INSTABILITY ADDED TO THE MIX. IMPACTS TO
ROADWAYS SEEN ON WEBCAMS AROUND THE REGION ARE MINIMAL BUT THERE
COULD BE SOME SNOW PACKED AND ICY SPOTS ON NORTH FACING SLOPES.
THIS IS LIKELY ON THE MESA WHERE THE BEST SNOW HAS FALLEN SINCE
MID MORNING. THE WAVE ADDING ASCENT WILL BE MOVING OVER WESTERN
COLORADO THIS EVENING AND SHOULD KEEP SOME TERRAIN BASED SHOWERS
GOING THROUGH MIDNIGHT...WITH NORTH/WEST FACING SLOPES FAVORED
LOOKING AT THE MID LEVEL FLOW. FROM SUNRISE INTO MID MORNING A FEW
SHOWERS MAY LINGER OVER THE NORTHERN MOUNTAINS...BUT AS TRANSITORY
RIDGING BRINGS IN WAA ALOFT DURING THE AFTERNOON...THE MORE STABLE
CONDITIONS SHOULD SHUT OFF MOST OF THE SHOWERS BY EARLY AFTERNOON.
THIS RIDGING REMAINS IN PLACE THROUGH EARLY SATURDAY BEFORE
UPSTREAM ENERGY PUSHES THE RIDGE AXIS TO THE HIGH PLAINS AND THE
FLOW TURNS MORE NORTHWESTERLY AND PROGRESSIVELY MORE MOIST.
TEMPERATURES UNDER THE RIDGE WILL STRUGGLE DUE TO RECENT SNOWFALL
AND PRECIPITATION...SO HIGHS NEAR OR SLIGHTLY BELOW NORMAL ARE IN
PLACE. THE BIGGER CHALLENGE TO THE FORECAST WILL BE LINGERING PBL
MOISTURE AND DRYING ALOFT TONIGHT. FOG WAS FAIRLY COMMON OVERNIGHT
AND THIS WILL BE THE CASE AGAIN OVERNIGHT. THERE WILL BE AREAS OF
DENSE FOG ALONG SOME VALLEY LOCATIONS BUT CONFIDENCE TOO LOW ATTM
TO HOIST ADVISORIES.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 332 PM MST THU DEC 18 2014

..SIGNIFICANT MOUNTAIN SNOWFALL POSSIBLE LATE THIS WEEKEND AND
EARLY NEXT WEEK. ANOTHER STORM POSSIBLE ON CHRISTMAS DAY...

MODELS CONTINUE TO POINT TOWARD AN EXTENDED PERIOD OF UNSETTLED
WEATHER THROUGH NEXT WEEK. THE PERSISTENT LONGWAVE RIDGE OVER THE
WESTERN STATES FLATTENS THIS WEEKEND AND THEN REBUILDS FARTHER TO
THE WEST OVER THE NORTHEASTERN PACIFIC OCEAN. THIS WILL FAVOR A MORE
CONSOLIDATED NORTHWEST FLOW OVER OUR AREA FOR MUCH OF NEXT WEEK WITH
A GENERALY COOLING IN TEMPERATURES...VERSUS THE SPLIT FLOW PATTERN
OF THE RECENT PAST.

ONE SHORTWAVE DISTURBANCE CROSSES ON SAT AND HELPS TO FLATTEN THE
RIDGE WHILE BRINGING A CHANCE OF LIGHT SNOW TO THE NORTHERN AND
PERHAPS CENTRAL MTNS.

A STRONG AND MOIST JET STREAM BLASTS INTO THE PACIFIC NORTHWEST THIS
WEEKEND AND ACROSS WY ON SUNDAY. THIS 120-130KT JET THEN BECOMES
ORIENTED NORTHWEST TO SOUTHEAST OVER CO MONDAY-MONDAY NIGHT AS THE
UPPER RIDGE BEGINS TO AMPLIFY OVER THE NERN PACIFIC. ABUNDANT
MOISTURE COMBINED WITH JET DYNAMICS AND OROGRAPHIC FORCING SHOULD
RESULT IN AN EXTENDED PERIOD OF SNOW FOR THE NORTHERN AND CENTRAL CO
MTNS SUNDAY AFTERNOON THROUGH MONDAY NIGHT. SCATTERED SNOW SHOWERS
WILL PERSIST ACROSS THE NRN MTNS TO VAIL TUE IN NW FLOW WHILE SNOW
DECREASES ELSEWHERE AS THE UPPER JET SLIPS EASTWARD. WINDY
CONDITIONS ARE LIKELY CREATING AREAS OF BLOWING SNOW AS WELL. TRAVEL
OVER THE RABBIT EARS AND VAIL PASSES LATE SUNDAY INTO TUESDAY WILL
BE NEGATIVELY IMPACTED AND WILL CONTINUE WITH THE SPECIAL WEATHER
STATEMENT ADDRESSING THIS.  BUT AS STATED IN THE EARLIER
DISCUSSION...WARM ADVECTION SUNDAY AFTERNOON/ EVENING MAY RESULT IN
LESSER SNOW AMTS INITIALLY BEFORE COLDER AIR SETTLES IN MONDAY AS
THE JET MOVES OVERHEAD.

MODELS INDICATE A BIT OF A BREAK LATE TUESDAY INTO WEDNESDAY AS A
TRANSITORY RIDGE MOVES ACROSS AHEAD OF THE NEXT TROUGH EXPECTED TO
ENTER THE PACIFIC NORTHWEST. 12Z ECWMF AND 12Z GFS NOW IN BETTER
AGREEMENT ON BRING THIS TROUGH ACROSS OUR AREA ON CHRISTMAS DAY FOR
A CHANCE OF SNOW. THIS IS A RATHER SIGNIFICANT CHANGE FOR THE ECWMF
WHICH HAD BEEN SHOWING THE TROUGH CLOSING OFF A MID-LEVEL LOW OVER
THE GREAT BASIN THU. WILL SEE IF THIS MODEL AGREEMENT CONTINUES.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1029 PM MST THU DEC 18 2014

BIGGEST CHALLENGE OF THE NIGHT WILL BE VISIBILITIES. ALREADY
SEEING DENSE FOG AT KCAG AND KSBS WITH K5SM NOT FAR BEHIND AT A
HALF MILE VIS. EXPECTING DENSE FOG TO BE INTERMITTENT THROUGHOUT
THE NIGHT AND NOT WIDESPREAD ACROSS WESTERN CO/EASTERN UT.

WIDESPREAD VFR EXPECTED ON FRIDAY...WITH HIGH CLOUDS INCREASING
FROM WEST TO EAST AFTER 23Z.


&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...DENSE FOG ADVISORY UNTIL 7 AM MST FRIDAY FOR COZ002-005.

UT...NONE.
&&

$$

SHORT TERM...15
LONG TERM...JAD
AVIATION...JAM




000
FXUS65 KGJT 190538
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1038 PM MST THU DEC 18 2014

.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 332 PM MST THU DEC 18 2014

THE ATMOSPHERE SEEMS TO BE VERY EFFICIENT IN MAKING SNOW TODAY
ESPECIALLY WITH A BIT OF INSTABILITY ADDED TO THE MIX. IMPACTS TO
ROADWAYS SEEN ON WEBCAMS AROUND THE REGION ARE MINIMAL BUT THERE
COULD BE SOME SNOW PACKED AND ICY SPOTS ON NORTH FACING SLOPES.
THIS IS LIKELY ON THE MESA WHERE THE BEST SNOW HAS FALLEN SINCE
MID MORNING. THE WAVE ADDING ASCENT WILL BE MOVING OVER WESTERN
COLORADO THIS EVENING AND SHOULD KEEP SOME TERRAIN BASED SHOWERS
GOING THROUGH MIDNIGHT...WITH NORTH/WEST FACING SLOPES FAVORED
LOOKING AT THE MID LEVEL FLOW. FROM SUNRISE INTO MID MORNING A FEW
SHOWERS MAY LINGER OVER THE NORTHERN MOUNTAINS...BUT AS TRANSITORY
RIDGING BRINGS IN WAA ALOFT DURING THE AFTERNOON...THE MORE STABLE
CONDITIONS SHOULD SHUT OFF MOST OF THE SHOWERS BY EARLY AFTERNOON.
THIS RIDGING REMAINS IN PLACE THROUGH EARLY SATURDAY BEFORE
UPSTREAM ENERGY PUSHES THE RIDGE AXIS TO THE HIGH PLAINS AND THE
FLOW TURNS MORE NORTHWESTERLY AND PROGRESSIVELY MORE MOIST.
TEMPERATURES UNDER THE RIDGE WILL STRUGGLE DUE TO RECENT SNOWFALL
AND PRECIPITATION...SO HIGHS NEAR OR SLIGHTLY BELOW NORMAL ARE IN
PLACE. THE BIGGER CHALLENGE TO THE FORECAST WILL BE LINGERING PBL
MOISTURE AND DRYING ALOFT TONIGHT. FOG WAS FAIRLY COMMON OVERNIGHT
AND THIS WILL BE THE CASE AGAIN OVERNIGHT. THERE WILL BE AREAS OF
DENSE FOG ALONG SOME VALLEY LOCATIONS BUT CONFIDENCE TOO LOW ATTM
TO HOIST ADVISORIES.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 332 PM MST THU DEC 18 2014

..SIGNIFICANT MOUNTAIN SNOWFALL POSSIBLE LATE THIS WEEKEND AND
EARLY NEXT WEEK. ANOTHER STORM POSSIBLE ON CHRISTMAS DAY...

MODELS CONTINUE TO POINT TOWARD AN EXTENDED PERIOD OF UNSETTLED
WEATHER THROUGH NEXT WEEK. THE PERSISTENT LONGWAVE RIDGE OVER THE
WESTERN STATES FLATTENS THIS WEEKEND AND THEN REBUILDS FARTHER TO
THE WEST OVER THE NORTHEASTERN PACIFIC OCEAN. THIS WILL FAVOR A MORE
CONSOLIDATED NORTHWEST FLOW OVER OUR AREA FOR MUCH OF NEXT WEEK WITH
A GENERALY COOLING IN TEMPERATURES...VERSUS THE SPLIT FLOW PATTERN
OF THE RECENT PAST.

ONE SHORTWAVE DISTURBANCE CROSSES ON SAT AND HELPS TO FLATTEN THE
RIDGE WHILE BRINGING A CHANCE OF LIGHT SNOW TO THE NORTHERN AND
PERHAPS CENTRAL MTNS.

A STRONG AND MOIST JET STREAM BLASTS INTO THE PACIFIC NORTHWEST THIS
WEEKEND AND ACROSS WY ON SUNDAY. THIS 120-130KT JET THEN BECOMES
ORIENTED NORTHWEST TO SOUTHEAST OVER CO MONDAY-MONDAY NIGHT AS THE
UPPER RIDGE BEGINS TO AMPLIFY OVER THE NERN PACIFIC. ABUNDANT
MOISTURE COMBINED WITH JET DYNAMICS AND OROGRAPHIC FORCING SHOULD
RESULT IN AN EXTENDED PERIOD OF SNOW FOR THE NORTHERN AND CENTRAL CO
MTNS SUNDAY AFTERNOON THROUGH MONDAY NIGHT. SCATTERED SNOW SHOWERS
WILL PERSIST ACROSS THE NRN MTNS TO VAIL TUE IN NW FLOW WHILE SNOW
DECREASES ELSEWHERE AS THE UPPER JET SLIPS EASTWARD. WINDY
CONDITIONS ARE LIKELY CREATING AREAS OF BLOWING SNOW AS WELL. TRAVEL
OVER THE RABBIT EARS AND VAIL PASSES LATE SUNDAY INTO TUESDAY WILL
BE NEGATIVELY IMPACTED AND WILL CONTINUE WITH THE SPECIAL WEATHER
STATEMENT ADDRESSING THIS.  BUT AS STATED IN THE EARLIER
DISCUSSION...WARM ADVECTION SUNDAY AFTERNOON/ EVENING MAY RESULT IN
LESSER SNOW AMTS INITIALLY BEFORE COLDER AIR SETTLES IN MONDAY AS
THE JET MOVES OVERHEAD.

MODELS INDICATE A BIT OF A BREAK LATE TUESDAY INTO WEDNESDAY AS A
TRANSITORY RIDGE MOVES ACROSS AHEAD OF THE NEXT TROUGH EXPECTED TO
ENTER THE PACIFIC NORTHWEST. 12Z ECWMF AND 12Z GFS NOW IN BETTER
AGREEMENT ON BRING THIS TROUGH ACROSS OUR AREA ON CHRISTMAS DAY FOR
A CHANCE OF SNOW. THIS IS A RATHER SIGNIFICANT CHANGE FOR THE ECWMF
WHICH HAD BEEN SHOWING THE TROUGH CLOSING OFF A MID-LEVEL LOW OVER
THE GREAT BASIN THU. WILL SEE IF THIS MODEL AGREEMENT CONTINUES.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1029 PM MST THU DEC 18 2014

BIGGEST CHALLENGE OF THE NIGHT WILL BE VISIBILITIES. ALREADY
SEEING DENSE FOG AT KCAG AND KSBS WITH K5SM NOT FAR BEHIND AT A
HALF MILE VIS. EXPECTING DENSE FOG TO BE INTERMITTENT THROUGHOUT
THE NIGHT AND NOT WIDESPREAD ACROSS WESTERN CO/EASTERN UT.

WIDESPREAD VFR EXPECTED ON FRIDAY...WITH HIGH CLOUDS INCREASING
FROM WEST TO EAST AFTER 23Z.


&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...DENSE FOG ADVISORY UNTIL 7 AM MST FRIDAY FOR COZ002-005.

UT...NONE.
&&

$$

SHORT TERM...15
LONG TERM...JAD
AVIATION...JAM





000
FXUS65 KGJT 190015
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
515 PM MST THU DEC 18 2014

.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 332 PM MST THU DEC 18 2014

THE ATMOSPHERE SEEMS TO BE VERY EFFICIENT IN MAKING SNOW TODAY
ESPECIALLY WITH A BIT OF INSTABILITY ADDED TO THE MIX. IMPACTS TO
ROADWAYS SEEN ON WEBCAMS AROUND THE REGION ARE MINIMAL BUT THERE
COULD BE SOME SNOW PACKED AND ICY SPOTS ON NORTH FACING SLOPES.
THIS IS LIKELY ON THE MESA WHERE THE BEST SNOW HAS FALLEN SINCE
MID MORNING. THE WAVE ADDING ASCENT WILL BE MOVING OVER WESTERN
COLORADO THIS EVENING AND SHOULD KEEP SOME TERRAIN BASED SHOWERS
GOING THROUGH MIDNIGHT...WITH NORTH/WEST FACING SLOPES FAVORED
LOOKING AT THE MID LEVEL FLOW. FROM SUNRISE INTO MID MORNING A FEW
SHOWERS MAY LINGER OVER THE NORTHERN MOUNTAINS...BUT AS TRANSITORY
RIDGING BRINGS IN WAA ALOFT DURING THE AFTERNOON...THE MORE STABLE
CONDITIONS SHOULD SHUT OFF MOST OF THE SHOWERS BY EARLY AFTERNOON.
THIS RIDGING REMAINS IN PLACE THROUGH EARLY SATURDAY BEFORE
UPSTREAM ENERGY PUSHES THE RIDGE AXIS TO THE HIGH PLAINS AND THE
FLOW TURNS MORE NORTHWESTERLY AND PROGRESSIVELY MORE MOIST.
TEMPERATURES UNDER THE RIDGE WILL STRUGGLE DUE TO RECENT SNOWFALL
AND PRECIPITATION...SO HIGHS NEAR OR SLIGHTLY BELOW NORMAL ARE IN
PLACE. THE BIGGER CHALLENGE TO THE FORECAST WILL BE LINGERING PBL
MOISTURE AND DRYING ALOFT TONIGHT. FOG WAS FAIRLY COMMON OVERNIGHT
AND THIS WILL BE THE CASE AGAIN OVERNIGHT. THERE WILL BE AREAS OF
DENSE FOG ALONG SOME VALLEY LOCATIONS BUT CONFIDENCE TOO LOW ATTM
TO HOIST ADVISORIES.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 332 PM MST THU DEC 18 2014

..SIGNIFICANT MOUNTAIN SNOWFALL POSSIBLE LATE THIS WEEKEND AND
EARLY NEXT WEEK. ANOTHER STORM POSSIBLE ON CHRISTMAS DAY...

MODELS CONTINUE TO POINT TOWARD AN EXTENDED PERIOD OF UNSETTLED
WEATHER THROUGH NEXT WEEK. THE PERSISTENT LONGWAVE RIDGE OVER THE
WESTERN STATES FLATTENS THIS WEEKEND AND THEN REBUILDS FARTHER TO
THE WEST OVER THE NORTHEASTERN PACIFIC OCEAN. THIS WILL FAVOR A MORE
CONSOLIDATED NORTHWEST FLOW OVER OUR AREA FOR MUCH OF NEXT WEEK WITH
A GENERALY COOLING IN TEMPERATURES...VERSUS THE SPLIT FLOW PATTERN
OF THE RECENT PAST.

ONE SHORTWAVE DISTURBANCE CROSSES ON SAT AND HELPS TO FLATTEN THE
RIDGE WHILE BRINGING A CHANCE OF LIGHT SNOW TO THE NORTHERN AND
PERHAPS CENTRAL MTNS.

A STRONG AND MOIST JET STREAM BLASTS INTO THE PACIFIC NORTHWEST THIS
WEEKEND AND ACROSS WY ON SUNDAY. THIS 120-130KT JET THEN BECOMES
ORIENTED NORTHWEST TO SOUTHEAST OVER CO MONDAY-MONDAY NIGHT AS THE
UPPER RIDGE BEGINS TO AMPLIFY OVER THE NERN PACIFIC. ABUNDANT
MOISTURE COMBINED WITH JET DYNAMICS AND OROGRAPHIC FORCING SHOULD
RESULT IN AN EXTENDED PERIOD OF SNOW FOR THE NORTHERN AND CENTRAL CO
MTNS SUNDAY AFTERNOON THROUGH MONDAY NIGHT. SCATTERED SNOW SHOWERS
WILL PERSIST ACROSS THE NRN MTNS TO VAIL TUE IN NW FLOW WHILE SNOW
DECREASES ELSEWHERE AS THE UPPER JET SLIPS EASTWARD. WINDY
CONDITIONS ARE LIKELY CREATING AREAS OF BLOWING SNOW AS WELL. TRAVEL
OVER THE RABBIT EARS AND VAIL PASSES LATE SUNDAY INTO TUESDAY WILL
BE NEGATIVELY IMPACTED AND WILL CONTINUE WITH THE SPECIAL WEATHER
STATEMENT ADDRESSING THIS.  BUT AS STATED IN THE EARLIER
DISCUSSION...WARM ADVECTION SUNDAY AFTERNOON/ EVENING MAY RESULT IN
LESSER SNOW AMTS INITIALLY BEFORE COLDER AIR SETTLES IN MONDAY AS
THE JET MOVES OVERHEAD.

MODELS INDICATE A BIT OF A BREAK LATE TUESDAY INTO WEDNESDAY AS A
TRANSITORY RIDGE MOVES ACROSS AHEAD OF THE NEXT TROUGH EXPECTED TO
ENTER THE PACIFIC NORTHWEST. 12Z ECWMF AND 12Z GFS NOW IN BETTER
AGREEMENT ON BRING THIS TROUGH ACROSS OUR AREA ON CHRISTMAS DAY FOR
A CHANCE OF SNOW. THIS IS A RATHER SIGNIFICANT CHANGE FOR THE ECWMF
WHICH HAD BEEN SHOWING THE TROUGH CLOSING OFF A MID-LEVEL LOW OVER
THE GREAT BASIN THU. WILL SEE IF THIS MODEL AGREEMENT CONTINUES.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 515 PM MST THU DEC 18 2014

IMPROVING CONDITIONS BETWEEN 00Z-15Z WITH DISSIPATING LOW LEVEL
CIGS AND DECREASING -SN. PATCHY FOG MAY LIMIT VIS AT RIVER AND
VALLEY BOTTOMS...BUT THIS HAZARD WILL BE MITIGATED BY LOWERING
DEW POINTS AND INVERSIONS WILL BE WEAK.

WIDESPREAD VFR CONDITIONS ACROSS THE ENTIRE REGION DURING THE DAY
ON FRIDAY.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&

$$

SHORT TERM...15
LONG TERM...JAD
AVIATION...PF





000
FXUS65 KGJT 190015
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
515 PM MST THU DEC 18 2014

.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 332 PM MST THU DEC 18 2014

THE ATMOSPHERE SEEMS TO BE VERY EFFICIENT IN MAKING SNOW TODAY
ESPECIALLY WITH A BIT OF INSTABILITY ADDED TO THE MIX. IMPACTS TO
ROADWAYS SEEN ON WEBCAMS AROUND THE REGION ARE MINIMAL BUT THERE
COULD BE SOME SNOW PACKED AND ICY SPOTS ON NORTH FACING SLOPES.
THIS IS LIKELY ON THE MESA WHERE THE BEST SNOW HAS FALLEN SINCE
MID MORNING. THE WAVE ADDING ASCENT WILL BE MOVING OVER WESTERN
COLORADO THIS EVENING AND SHOULD KEEP SOME TERRAIN BASED SHOWERS
GOING THROUGH MIDNIGHT...WITH NORTH/WEST FACING SLOPES FAVORED
LOOKING AT THE MID LEVEL FLOW. FROM SUNRISE INTO MID MORNING A FEW
SHOWERS MAY LINGER OVER THE NORTHERN MOUNTAINS...BUT AS TRANSITORY
RIDGING BRINGS IN WAA ALOFT DURING THE AFTERNOON...THE MORE STABLE
CONDITIONS SHOULD SHUT OFF MOST OF THE SHOWERS BY EARLY AFTERNOON.
THIS RIDGING REMAINS IN PLACE THROUGH EARLY SATURDAY BEFORE
UPSTREAM ENERGY PUSHES THE RIDGE AXIS TO THE HIGH PLAINS AND THE
FLOW TURNS MORE NORTHWESTERLY AND PROGRESSIVELY MORE MOIST.
TEMPERATURES UNDER THE RIDGE WILL STRUGGLE DUE TO RECENT SNOWFALL
AND PRECIPITATION...SO HIGHS NEAR OR SLIGHTLY BELOW NORMAL ARE IN
PLACE. THE BIGGER CHALLENGE TO THE FORECAST WILL BE LINGERING PBL
MOISTURE AND DRYING ALOFT TONIGHT. FOG WAS FAIRLY COMMON OVERNIGHT
AND THIS WILL BE THE CASE AGAIN OVERNIGHT. THERE WILL BE AREAS OF
DENSE FOG ALONG SOME VALLEY LOCATIONS BUT CONFIDENCE TOO LOW ATTM
TO HOIST ADVISORIES.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 332 PM MST THU DEC 18 2014

..SIGNIFICANT MOUNTAIN SNOWFALL POSSIBLE LATE THIS WEEKEND AND
EARLY NEXT WEEK. ANOTHER STORM POSSIBLE ON CHRISTMAS DAY...

MODELS CONTINUE TO POINT TOWARD AN EXTENDED PERIOD OF UNSETTLED
WEATHER THROUGH NEXT WEEK. THE PERSISTENT LONGWAVE RIDGE OVER THE
WESTERN STATES FLATTENS THIS WEEKEND AND THEN REBUILDS FARTHER TO
THE WEST OVER THE NORTHEASTERN PACIFIC OCEAN. THIS WILL FAVOR A MORE
CONSOLIDATED NORTHWEST FLOW OVER OUR AREA FOR MUCH OF NEXT WEEK WITH
A GENERALY COOLING IN TEMPERATURES...VERSUS THE SPLIT FLOW PATTERN
OF THE RECENT PAST.

ONE SHORTWAVE DISTURBANCE CROSSES ON SAT AND HELPS TO FLATTEN THE
RIDGE WHILE BRINGING A CHANCE OF LIGHT SNOW TO THE NORTHERN AND
PERHAPS CENTRAL MTNS.

A STRONG AND MOIST JET STREAM BLASTS INTO THE PACIFIC NORTHWEST THIS
WEEKEND AND ACROSS WY ON SUNDAY. THIS 120-130KT JET THEN BECOMES
ORIENTED NORTHWEST TO SOUTHEAST OVER CO MONDAY-MONDAY NIGHT AS THE
UPPER RIDGE BEGINS TO AMPLIFY OVER THE NERN PACIFIC. ABUNDANT
MOISTURE COMBINED WITH JET DYNAMICS AND OROGRAPHIC FORCING SHOULD
RESULT IN AN EXTENDED PERIOD OF SNOW FOR THE NORTHERN AND CENTRAL CO
MTNS SUNDAY AFTERNOON THROUGH MONDAY NIGHT. SCATTERED SNOW SHOWERS
WILL PERSIST ACROSS THE NRN MTNS TO VAIL TUE IN NW FLOW WHILE SNOW
DECREASES ELSEWHERE AS THE UPPER JET SLIPS EASTWARD. WINDY
CONDITIONS ARE LIKELY CREATING AREAS OF BLOWING SNOW AS WELL. TRAVEL
OVER THE RABBIT EARS AND VAIL PASSES LATE SUNDAY INTO TUESDAY WILL
BE NEGATIVELY IMPACTED AND WILL CONTINUE WITH THE SPECIAL WEATHER
STATEMENT ADDRESSING THIS.  BUT AS STATED IN THE EARLIER
DISCUSSION...WARM ADVECTION SUNDAY AFTERNOON/ EVENING MAY RESULT IN
LESSER SNOW AMTS INITIALLY BEFORE COLDER AIR SETTLES IN MONDAY AS
THE JET MOVES OVERHEAD.

MODELS INDICATE A BIT OF A BREAK LATE TUESDAY INTO WEDNESDAY AS A
TRANSITORY RIDGE MOVES ACROSS AHEAD OF THE NEXT TROUGH EXPECTED TO
ENTER THE PACIFIC NORTHWEST. 12Z ECWMF AND 12Z GFS NOW IN BETTER
AGREEMENT ON BRING THIS TROUGH ACROSS OUR AREA ON CHRISTMAS DAY FOR
A CHANCE OF SNOW. THIS IS A RATHER SIGNIFICANT CHANGE FOR THE ECWMF
WHICH HAD BEEN SHOWING THE TROUGH CLOSING OFF A MID-LEVEL LOW OVER
THE GREAT BASIN THU. WILL SEE IF THIS MODEL AGREEMENT CONTINUES.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 515 PM MST THU DEC 18 2014

IMPROVING CONDITIONS BETWEEN 00Z-15Z WITH DISSIPATING LOW LEVEL
CIGS AND DECREASING -SN. PATCHY FOG MAY LIMIT VIS AT RIVER AND
VALLEY BOTTOMS...BUT THIS HAZARD WILL BE MITIGATED BY LOWERING
DEW POINTS AND INVERSIONS WILL BE WEAK.

WIDESPREAD VFR CONDITIONS ACROSS THE ENTIRE REGION DURING THE DAY
ON FRIDAY.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&

$$

SHORT TERM...15
LONG TERM...JAD
AVIATION...PF




000
FXUS65 KGJT 182233
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
333 PM MST THU DEC 18 2014

.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 332 PM MST THU DEC 18 2014

THE ATMOSPHERE SEEMS TO BE VERY EFFICIENT IN MAKING SNOW TODAY
ESPECIALLY WITH A BIT OF INSTABILITY ADDED TO THE MIX. IMPACTS TO
ROADWAYS SEEN ON WEBCAMS AROUND THE REGION ARE MINIMAL BUT THERE
COULD BE SOME SNOW PACKED AND ICY SPOTS ON NORTH FACING SLOPES.
THIS IS LIKELY ON THE MESA WHERE THE BEST SNOW HAS FALLEN SINCE
MID MORNING. THE WAVE ADDING ASCENT WILL BE MOVING OVER WESTERN
COLORADO THIS EVENING AND SHOULD KEEP SOME TERRAIN BASED SHOWERS
GOING THROUGH MIDNIGHT...WITH NORTH/WEST FACING SLOPES FAVORED
LOOKING AT THE MID LEVEL FLOW. FROM SUNRISE INTO MID MORNING A FEW
SHOWERS MAY LINGER OVER THE NORTHERN MOUNTAINS...BUT AS TRANSITORY
RIDGING BRINGS IN WAA ALOFT DURING THE AFTERNOON...THE MORE STABLE
CONDITIONS SHOULD SHUT OFF MOST OF THE SHOWERS BY EARLY AFTERNOON.
THIS RIDGING REMAINS IN PLACE THROUGH EARLY SATURDAY BEFORE
UPSTREAM ENERGY PUSHES THE RIDGE AXIS TO THE HIGH PLAINS AND THE
FLOW TURNS MORE NORTHWESTERLY AND PROGRESSIVELY MORE MOIST.
TEMPERATURES UNDER THE RIDGE WILL STRUGGLE DUE TO RECENT SNOWFALL
AND PRECIPITATION...SO HIGHS NEAR OR SLIGHTLY BELOW NORMAL ARE IN
PLACE. THE BIGGER CHALLENGE TO THE FORECAST WILL BE LINGERING PBL
MOISTURE AND DRYING ALOFT TONIGHT. FOG WAS FAIRLY COMMON OVERNIGHT
AND THIS WILL BE THE CASE AGAIN OVERNIGHT. THERE WILL BE AREAS OF
DENSE FOG ALONG SOME VALLEY LOCATIONS BUT CONFIDENCE TOO LOW ATTM
TO HOIST ADVISORIES.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 332 PM MST THU DEC 18 2014

..SIGNIFICANT MOUNTAIN SNOWFALL POSSIBLE LATE THIS WEEKEND AND
EARLY NEXT WEEK. ANOTHER STORM POSSIBLE ON CHRISTMAS DAY...

MODELS CONTINUE TO POINT TOWARD AN EXTENDED PERIOD OF UNSETTLED
WEATHER THROUGH NEXT WEEK. THE PERSISTENT LONGWAVE RIDGE OVER THE
WESTERN STATES FLATTENS THIS WEEKEND AND THEN REBUILDS FARTHER TO
THE WEST OVER THE NORTHEASTERN PACIFIC OCEAN. THIS WILL FAVOR A MORE
CONSOLIDATED NORTHWEST FLOW OVER OUR AREA FOR MUCH OF NEXT WEEK WITH
A GENERALY COOLING IN TEMPERATURES...VERSUS THE SPLIT FLOW PATTERN
OF THE RECENT PAST.

ONE SHORTWAVE DISTURBANCE CROSSES ON SAT AND HELPS TO FLATTEN THE
RIDGE WHILE BRINGING A CHANCE OF LIGHT SNOW TO THE NORTHERN AND
PERHAPS CENTRAL MTNS.

A STRONG AND MOIST JET STREAM BLASTS INTO THE PACIFIC NORTHWEST THIS
WEEKEND AND ACROSS WY ON SUNDAY. THIS 120-130KT JET THEN BECOMES
ORIENTED NORTHWEST TO SOUTHEAST OVER CO MONDAY-MONDAY NIGHT AS THE
UPPER RIDGE BEGINS TO AMPLIFY OVER THE NERN PACIFIC. ABUNDANT
MOISTURE COMBINED WITH JET DYNAMICS AND OROGRAPHIC FORCING SHOULD
RESULT IN AN EXTENDED PERIOD OF SNOW FOR THE NORTHERN AND CENTRAL CO
MTNS SUNDAY AFTERNOON THROUGH MONDAY NIGHT. SCATTERED SNOW SHOWERS
WILL PERSIST ACROSS THE NRN MTNS TO VAIL TUE IN NW FLOW WHILE SNOW
DECREASES ELSEWHERE AS THE UPPER JET SLIPS EASTWARD. WINDY
CONDITIONS ARE LIKELY CREATING AREAS OF BLOWING SNOW AS WELL. TRAVEL
OVER THE RABBIT EARS AND VAIL PASSES LATE SUNDAY INTO TUESDAY WILL
BE NEGATIVELY IMPACTED AND WILL CONTINUE WITH THE SPECIAL WEATHER
STATEMENT ADDRESSING THIS.  BUT AS STATED IN THE EARLIER
DISCUSSION...WARM ADVECTION SUNDAY AFTERNOON/ EVENING MAY RESULT IN
LESSER SNOW AMTS INITIALLY BEFORE COLDER AIR SETTLES IN MONDAY AS
THE JET MOVES OVERHEAD.

MODELS INDICATE A BIT OF A BREAK LATE TUESDAY INTO WEDNESDAY AS A
TRANSITORY RIDGE MOVES ACROSS AHEAD OF THE NEXT TROUGH EXPECTED TO
ENTER THE PACIFIC NORTHWEST. 12Z ECWMF AND 12Z GFS NOW IN BETTER
AGREEMENT ON BRING THIS TROUGH ACROSS OUR AREA ON CHRISTMAS DAY FOR
A CHANCE OF SNOW. THIS IS A RATHER SIGNIFICANT CHANGE FOR THE ECWMF
WHICH HAD BEEN SHOWING THE TROUGH CLOSING OFF A MID-LEVEL LOW OVER
THE GREAT BASIN THU. WILL SEE IF THIS MODEL AGREEMENT CONTINUES.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1039 AM MST THU DEC 18 2014

LOW LEVEL MOISTURE IS ABUNDANT ACROSS EASTERN UTAH AND WESTERN
COLORADO LATE THIS MORNING. THIS IS KEEPING AREAS OF MVFR CIGS AND
AREAS OF IFR FOG IN PLACE ACROSS MOST OF THE VALLEY REGIONS WHILE
HIGHER TERRAIN AREAS ARE AT VFR LEVELS SUCH AS TEX. ANOTHER WEAK
RIPPLE IN FLOW MOVING THROUGH THIS AFTERNOON SHOULD REBUILD CLOUDS
OVER THE HIGHER TERRAIN AND KEEP SCATTERED PRECIPITATION IN THE
FORECAST. MVFR FLIGHT CONDITIONS ARE LIKELY TO PREVAIL OR BE IN
THE VICINITY OF THE THE FLIGHT TERMINALS THROUGH SUNSET. AFTER
SUNSET DRIER AIR MOVES IN ALOFT BUT THIS WILL LIKELY LEAD TO FOG
FORMATION AS MOISTURE HANGS CLOSE TO THE SURFACE. CONFIDENCE NEVER
HIGH IN FOG FORECASTING SO FOR NOW MAINLY HINTING AT IN TAF
FORECAST. HOWEVER PLANS SHOULD BE MADE FOR AIRPORT MINIMUMS AND
ALTERNATE FLIGHT ROUTES OVERNIGHT.


&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&

$$

SHORT TERM...15
LONG TERM...JAD
AVIATION...TGJT




000
FXUS65 KGJT 182233
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
333 PM MST THU DEC 18 2014

.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 332 PM MST THU DEC 18 2014

THE ATMOSPHERE SEEMS TO BE VERY EFFICIENT IN MAKING SNOW TODAY
ESPECIALLY WITH A BIT OF INSTABILITY ADDED TO THE MIX. IMPACTS TO
ROADWAYS SEEN ON WEBCAMS AROUND THE REGION ARE MINIMAL BUT THERE
COULD BE SOME SNOW PACKED AND ICY SPOTS ON NORTH FACING SLOPES.
THIS IS LIKELY ON THE MESA WHERE THE BEST SNOW HAS FALLEN SINCE
MID MORNING. THE WAVE ADDING ASCENT WILL BE MOVING OVER WESTERN
COLORADO THIS EVENING AND SHOULD KEEP SOME TERRAIN BASED SHOWERS
GOING THROUGH MIDNIGHT...WITH NORTH/WEST FACING SLOPES FAVORED
LOOKING AT THE MID LEVEL FLOW. FROM SUNRISE INTO MID MORNING A FEW
SHOWERS MAY LINGER OVER THE NORTHERN MOUNTAINS...BUT AS TRANSITORY
RIDGING BRINGS IN WAA ALOFT DURING THE AFTERNOON...THE MORE STABLE
CONDITIONS SHOULD SHUT OFF MOST OF THE SHOWERS BY EARLY AFTERNOON.
THIS RIDGING REMAINS IN PLACE THROUGH EARLY SATURDAY BEFORE
UPSTREAM ENERGY PUSHES THE RIDGE AXIS TO THE HIGH PLAINS AND THE
FLOW TURNS MORE NORTHWESTERLY AND PROGRESSIVELY MORE MOIST.
TEMPERATURES UNDER THE RIDGE WILL STRUGGLE DUE TO RECENT SNOWFALL
AND PRECIPITATION...SO HIGHS NEAR OR SLIGHTLY BELOW NORMAL ARE IN
PLACE. THE BIGGER CHALLENGE TO THE FORECAST WILL BE LINGERING PBL
MOISTURE AND DRYING ALOFT TONIGHT. FOG WAS FAIRLY COMMON OVERNIGHT
AND THIS WILL BE THE CASE AGAIN OVERNIGHT. THERE WILL BE AREAS OF
DENSE FOG ALONG SOME VALLEY LOCATIONS BUT CONFIDENCE TOO LOW ATTM
TO HOIST ADVISORIES.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 332 PM MST THU DEC 18 2014

..SIGNIFICANT MOUNTAIN SNOWFALL POSSIBLE LATE THIS WEEKEND AND
EARLY NEXT WEEK. ANOTHER STORM POSSIBLE ON CHRISTMAS DAY...

MODELS CONTINUE TO POINT TOWARD AN EXTENDED PERIOD OF UNSETTLED
WEATHER THROUGH NEXT WEEK. THE PERSISTENT LONGWAVE RIDGE OVER THE
WESTERN STATES FLATTENS THIS WEEKEND AND THEN REBUILDS FARTHER TO
THE WEST OVER THE NORTHEASTERN PACIFIC OCEAN. THIS WILL FAVOR A MORE
CONSOLIDATED NORTHWEST FLOW OVER OUR AREA FOR MUCH OF NEXT WEEK WITH
A GENERALY COOLING IN TEMPERATURES...VERSUS THE SPLIT FLOW PATTERN
OF THE RECENT PAST.

ONE SHORTWAVE DISTURBANCE CROSSES ON SAT AND HELPS TO FLATTEN THE
RIDGE WHILE BRINGING A CHANCE OF LIGHT SNOW TO THE NORTHERN AND
PERHAPS CENTRAL MTNS.

A STRONG AND MOIST JET STREAM BLASTS INTO THE PACIFIC NORTHWEST THIS
WEEKEND AND ACROSS WY ON SUNDAY. THIS 120-130KT JET THEN BECOMES
ORIENTED NORTHWEST TO SOUTHEAST OVER CO MONDAY-MONDAY NIGHT AS THE
UPPER RIDGE BEGINS TO AMPLIFY OVER THE NERN PACIFIC. ABUNDANT
MOISTURE COMBINED WITH JET DYNAMICS AND OROGRAPHIC FORCING SHOULD
RESULT IN AN EXTENDED PERIOD OF SNOW FOR THE NORTHERN AND CENTRAL CO
MTNS SUNDAY AFTERNOON THROUGH MONDAY NIGHT. SCATTERED SNOW SHOWERS
WILL PERSIST ACROSS THE NRN MTNS TO VAIL TUE IN NW FLOW WHILE SNOW
DECREASES ELSEWHERE AS THE UPPER JET SLIPS EASTWARD. WINDY
CONDITIONS ARE LIKELY CREATING AREAS OF BLOWING SNOW AS WELL. TRAVEL
OVER THE RABBIT EARS AND VAIL PASSES LATE SUNDAY INTO TUESDAY WILL
BE NEGATIVELY IMPACTED AND WILL CONTINUE WITH THE SPECIAL WEATHER
STATEMENT ADDRESSING THIS.  BUT AS STATED IN THE EARLIER
DISCUSSION...WARM ADVECTION SUNDAY AFTERNOON/ EVENING MAY RESULT IN
LESSER SNOW AMTS INITIALLY BEFORE COLDER AIR SETTLES IN MONDAY AS
THE JET MOVES OVERHEAD.

MODELS INDICATE A BIT OF A BREAK LATE TUESDAY INTO WEDNESDAY AS A
TRANSITORY RIDGE MOVES ACROSS AHEAD OF THE NEXT TROUGH EXPECTED TO
ENTER THE PACIFIC NORTHWEST. 12Z ECWMF AND 12Z GFS NOW IN BETTER
AGREEMENT ON BRING THIS TROUGH ACROSS OUR AREA ON CHRISTMAS DAY FOR
A CHANCE OF SNOW. THIS IS A RATHER SIGNIFICANT CHANGE FOR THE ECWMF
WHICH HAD BEEN SHOWING THE TROUGH CLOSING OFF A MID-LEVEL LOW OVER
THE GREAT BASIN THU. WILL SEE IF THIS MODEL AGREEMENT CONTINUES.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1039 AM MST THU DEC 18 2014

LOW LEVEL MOISTURE IS ABUNDANT ACROSS EASTERN UTAH AND WESTERN
COLORADO LATE THIS MORNING. THIS IS KEEPING AREAS OF MVFR CIGS AND
AREAS OF IFR FOG IN PLACE ACROSS MOST OF THE VALLEY REGIONS WHILE
HIGHER TERRAIN AREAS ARE AT VFR LEVELS SUCH AS TEX. ANOTHER WEAK
RIPPLE IN FLOW MOVING THROUGH THIS AFTERNOON SHOULD REBUILD CLOUDS
OVER THE HIGHER TERRAIN AND KEEP SCATTERED PRECIPITATION IN THE
FORECAST. MVFR FLIGHT CONDITIONS ARE LIKELY TO PREVAIL OR BE IN
THE VICINITY OF THE THE FLIGHT TERMINALS THROUGH SUNSET. AFTER
SUNSET DRIER AIR MOVES IN ALOFT BUT THIS WILL LIKELY LEAD TO FOG
FORMATION AS MOISTURE HANGS CLOSE TO THE SURFACE. CONFIDENCE NEVER
HIGH IN FOG FORECASTING SO FOR NOW MAINLY HINTING AT IN TAF
FORECAST. HOWEVER PLANS SHOULD BE MADE FOR AIRPORT MINIMUMS AND
ALTERNATE FLIGHT ROUTES OVERNIGHT.


&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&

$$

SHORT TERM...15
LONG TERM...JAD
AVIATION...TGJT





000
FXUS65 KGJT 181739
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1039 AM MST THU DEC 18 2014

.UPDATE...
ISSUED AT 910 AM MST THU DEC 18 2014

WENT AHEAD AND DROPPED THE ADVISORIES THIS MORNING WITH CLEARING
MOVING INTO THE SOUTHERN MOUNTAINS. ACROSS THE MESA INTO THE
CENTRAL COLORADO HIGH MOUNTAINS LIGHT SNOW SHOWERS AND FOG LIKELY
TO PERSIST THROUGH THE DAY THOUGH THE NATURE OF THE PRECIPITATION
WILL BECOME MORE SHOWERY. UPSTREAM ENERGY...PHASED FROM THE MORE
DEFINED SYSTEM IN ARIZONA TO THE NORTHERN ROCKIES...WILL MOVE
THROUGH THE CWA. INSTABILITY AND RESIDUAL MOISTURE SHOULD BE
ENOUGH TO KEEP ISOLATED TO SCATTERED SHOWERS IN THE PICTURE
THROUGH SUNSET. EXPECT SOME OF THE SHOWERS COULD DUMP A QUICK HALF
INCH BUT WITH COVERAGE LIMITED DO NOT EXPECT SIGNIFICANT IMPACTS
ATTM. FOG MAY BE MORE OF A PROBLEM THROUGH THE LATE MORNING HOURS
THEN AGAIN OVERNIGHT SO WILL BE MONITORING THIS AS WELL.

&&

.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 445 AM MST THU DEC 18 2014

THOUGH RETURNS ON RADAR ARE WEAK AND SATELLITE IMAGERY INDICATES
LOW CLOUD TOPS...THE SNOW IS STILL FLYING ACROSS PARTS OF WEST
CENTRAL COLORADO. AT MIDNIGHT WE RECEIVED REPORTS OF AN ONGOING
GORGE EVENT WITH 7 INCHES OF SNOW REPORTED IN THE GORGE ON HIGHWAY
550 JUST SOUTH OF OURAY BUT ONLY 3 INCHES JUST SOUTH OF THE GORGE
AREA AT RED MTN PASS. EXPECTING THIS EVENT WILL WRAP UP AROUND 6
OR 7AM AS NEGATIVE OMEGA SUPPORT SLIDES TO THE NORTH.

DEEP ATMOSPHERIC MOISTURE CONTINUES TODAY WHICH WILL KEEP THE
FORECAST AREA IN AN UNSETTLED PATTERN. THE MAIN BULK OF PRECIPITATION
IS EXPECTED TO SHIFT NORTH AND EAST TODAY AS THE WIND SHIFTS TO A
MORE WEST- NORTHWESTERLY DIRECTION...HOWEVER THE SAN JUANS WILL
STILL REMAIN SHOWERY THROUGHOUT THE DAY. UPPER LEVEL DIVERGENCE
INCREASES THIS EVENING WHICH SHOULD KEEP SHOWERS GOING INTO THE
OVERNIGHT HOURS AT HIGHER LOCATIONS. FOG WILL BE THE BIGGEST
CHALLENGE OF THE DAY AND TONIGHT AS RH REMAINS HIGH AND SURFACE
MOISTURE HAS A TOUGH TIME DRYING OUT WITH CONTINUED CLOUD COVER.

ON FRIDAY...UPPER LEVEL RIDGING BUILDS INTO THE AREA FOR A BRIEF
LULL IN ACTIVE WEATHER. TEMPERATURES WILL REMAIN NEAR NORMAL THE
NEXT COUPLE OF DAYS. THE GROUND SHOULD GET A CHANCE TO DRY OUT ON
FRIDAY DURING THE LULL OF ACTIVITY SO FOG WILL BE LESS WIDESPREAD
FRIDAY EVENING.

.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 445 AM MST THU DEC 18 2014

...SIGNIFICANT SNOWFALL POSSIBLE FOR THE NORTHERN AND CENTRAL
MOUNTAINS SUNDAY AFTERNOON THROUGH TUESDAY NIGHT...

PACIFIC ENERGY KICKING OUT OF THE PACIFIC NORTHWEST FRIDAY NIGHT
WILL DRAG ACROSS THE NORTHERN ZONES AND BRING A QUICK SHOT OF SNOW
THROUGH SATURDAY MORNING. SYSTEM IS UNORGANIZED AND WILL WEAKEN AS
IT ENCOUNTERS WEAK RIDGING OVER THE REGION...LIMITING POTENTIAL
IMPACT ON OUR FORECAST AREA. THIS WAVE EXITS SATURDAY AFTERNOON
WITH A BRIEF BREAK AHEAD OF WHAT IS LOOKING LIKE A LONG
DURATION...PERSISTENTLY MOIST NORTHWESTERLY FLOW EVENT THAT
STARTS SUNDAY AFTERNOON AND CONTINUES THROUGH TUESDAY NIGHT.

MEDIUM RANGE MODELS IN GOOD AGREEMENT THIS MORNING WITH SENDING A
SERIES OF FAST MOVING WAVES THROUGH THE PACIFIC NORTHWEST WITH
ABUNDANT PACIFIC MOISTURE AND SLAMMING THIS INTO OUR NORTHERN AND
CENTRAL MOUNTAINS. SPECIFIC HUMIDITY EXCEED 3 G/KG FOR A LARGE
DURATION WITH STRONG JET SUPPORT AS A 120+ JET DRIVES THE MOISTURE
INTO OUR AREA. BASED ON CURRENT SET-UP IN THE MODELS...A PROLONGED
PERIOD OF MOIST PACIFIC FLOW AND VERY FAVORABLE OROGRAPHICS TO
BRING SUBSTANTIAL SNOWFALL OVER A 2+ DAY PERIOD BEGINNING SUNDAY
AFTERNOON. THE HEAVIEST SNOW IS EXPECTED TO FALL ACROSS THE
NORTHERN AND CENTRAL MOUNTAINS IN WESTERN COLORADO...WITH FOCUS
FROM VAIL PASS NORTHWARD TO STEAMBOAT SPRINGS. STILL TIME TO WORK
OUT THE DETAILS...BUT APPEARS WE WILL BE LOOKING AT SEVERAL WINTER
HIGHLIGHTS BY LATE THIS WEEKEND INTO EARLY NEXT WEEK.

HOWEVER...AND THERE IS ALWAYS A HOWEVER...WAA COULD AND MOST
LIKELY WILL CREATE SOME PROBLEMS WITH THE MODEL GENERATED QPF
VALUES...THUS SNOWFALL ACCUMULATIONS MAY BE OVERBLOWN. WILL GET A
BETTER HANDLE ON THIS AS THE EVENT DRAWS CLOSER. EVEN WITH THAT
CONCERN...WILL STILL BE ISSUING AN SPS LATER THIS MORNING AS THIS
WILL BE A HEAVY TRAVEL WEEK AND POTENTIAL IMPACTS COULD BE LARGE
AS SNOWFALL MAY BE MEASURED IN FEET ACROSS SOME OF OUR
MOUNTAINS...WITH THE GFS GENERATING OVER 3 FEET IN SOME AREAS BY
MIDWEEK. EVEN HALF OF THAT AMOUNT WILL CAUSE IMPACTS ON HOLIDAY
TRAVEL PLANS. OTHER AREAS WILL GET INTO THE ACTION AS WELL...BUT
THE EMPHASIS LOOKS TO BE ACROSS THE NORTHERN ZONES ATTM.
TEMPERATURES MODERATE A BIT...ESPECIALLY AS THE COLDER VALLEYS MIX
MONDAY AND TUESDAY.

AND THEN THERE IS THE POTENTIAL CHRISTMAS DAY STORM...ALTHOUGH
MODELS DIVERGE A BIT ON THIS STORM WITH THE ECMWF CLOSING A LOW
OVER THE GREAT BASIN WHEREAS THE GFS REMAINS MORE OPEN. EITHER
SOLUTION BRINGS MORE SNOW TO THE REGION...WITH THE EC MORE
FAVORABLE FOR SNOW INTO THE VALLEYS. WILL JUST RAMP POPS UP FOR
NOW WITH A COOL DOWN IN TEMPS EXPECTED.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1039 AM MST THU DEC 18 2014

LOW LEVEL MOISTURE IS ABUNDANT ACROSS EASTERN UTAH AND WESTERN
COLORADO LATE THIS MORNING. THIS IS KEEPING AREAS OF MVFR CIGS AND
AREAS OF IFR FOG IN PLACE ACROSS MOST OF THE VALLEY REGIONS WHILE
HIGHER TERRAIN AREAS ARE AT VFR LEVELS SUCH AS TEX. ANOTHER WEAK
RIPPLE IN FLOW MOVING THROUGH THIS AFTERNOON SHOULD REBUILD CLOUDS
OVER THE HIGHER TERRAIN AND KEEP SCATTERED PRECIPITATION IN THE
FORECAST. MVFR FLIGHT CONDITIONS ARE LIKELY TO PREVAIL OR BE IN
THE VICINITY OF THE THE FLIGHT TERMINALS THROUGH SUNSET. AFTER
SUNSET DRIER AIR MOVES IN ALOFT BUT THIS WILL LIKELY LEAD TO FOG
FORMATION AS MOISTURE HANGS CLOSE TO THE SURFACE. CONFIDENCE NEVER
HIGH IN FOG FORECASTING SO FOR NOW MAINLY HINTING AT IN TAF
FORECAST. HOWEVER PLANS SHOULD BE MADE FOR AIRPORT MINIMUMS AND
ALTERNATE FLIGHT ROUTES OVERNIGHT.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&

$$

UPDATE...15
SHORT TERM...JAM
LONG TERM...JDC
AVIATION...TGJT





000
FXUS65 KGJT 181615
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
915 AM MST THU DEC 18 2014

.UPDATE...
ISSUED AT 910 AM MST THU DEC 18 2014

WENT AHEAD AND DROPPED THE ADVISORIES THIS MORNING WITH CLEARING
MOVING INTO THE SOUTHERN MOUNTAINS. ACROSS THE MESA INTO THE
CENTRAL COLORADO HIGH MOUNTAINS LIGHT SNOW SHOWERS AND FOG LIKELY
TO PERSIST THROUGH THE DAY THOUGH THE NATURE OF THE PRECIPITATION
WILL BECOME MORE SHOWERY. UPSTREAM ENERGY...PHASED FROM THE MORE
DEFINED SYSTEM IN ARIZONA TO THE NORTHERN ROCKIES...WILL MOVE
THROUGH THE CWA. INSTABILITY AND RESIDUAL MOISTURE SHOULD BE
ENOUGH TO KEEP ISOLATED TO SCATTERED SHOWERS IN THE PICTURE
THROUGH SUNSET. EXPECT SOME OF THE SHOWERS COULD DUMP A QUICK HALF
INCH BUT WITH COVERAGE LIMITED DO NOT EXPECT SIGNIFICANT IMPACTS
ATTM. FOG MAY BE MORE OF A PROBLEM THROUGH THE LATE MORNING HOURS
THEN AGAIN OVERNIGHT SO WILL BE MONITORING THIS AS WELL.

&&

.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 445 AM MST THU DEC 18 2014

THOUGH RETURNS ON RADAR ARE WEAK AND SATELLITE IMAGERY INDICATES
LOW CLOUD TOPS...THE SNOW IS STILL FLYING ACROSS PARTS OF WEST
CENTRAL COLORADO. AT MIDNIGHT WE RECEIVED REPORTS OF AN ONGOING
GORGE EVENT WITH 7 INCHES OF SNOW REPORTED IN THE GORGE ON HIGHWAY
550 JUST SOUTH OF OURAY BUT ONLY 3 INCHES JUST SOUTH OF THE GORGE
AREA AT RED MTN PASS. EXPECTING THIS EVENT WILL WRAP UP AROUND 6
OR 7AM AS NEGATIVE OMEGA SUPPORT SLIDES TO THE NORTH.

DEEP ATMOSPHERIC MOISTURE CONTINUES TODAY WHICH WILL KEEP THE
FORECAST AREA IN AN UNSETTLED PATTERN. THE MAIN BULK OF PRECIPITATION
IS EXPECTED TO SHIFT NORTH AND EAST TODAY AS THE WIND SHIFTS TO A
MORE WEST- NORTHWESTERLY DIRECTION...HOWEVER THE SAN JUANS WILL
STILL REMAIN SHOWERY THROUGHOUT THE DAY. UPPER LEVEL DIVERGENCE
INCREASES THIS EVENING WHICH SHOULD KEEP SHOWERS GOING INTO THE
OVERNIGHT HOURS AT HIGHER LOCATIONS. FOG WILL BE THE BIGGEST
CHALLENGE OF THE DAY AND TONIGHT AS RH REMAINS HIGH AND SURFACE
MOISTURE HAS A TOUGH TIME DRYING OUT WITH CONTINUED CLOUD COVER.

ON FRIDAY...UPPER LEVEL RIDGING BUILDS INTO THE AREA FOR A BRIEF
LULL IN ACTIVE WEATHER. TEMPERATURES WILL REMAIN NEAR NORMAL THE
NEXT COUPLE OF DAYS. THE GROUND SHOULD GET A CHANCE TO DRY OUT ON
FRIDAY DURING THE LULL OF ACTIVITY SO FOG WILL BE LESS WIDESPREAD
FRIDAY EVENING.

.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 445 AM MST THU DEC 18 2014

...SIGNIFICANT SNOWFALL POSSIBLE FOR THE NORTHERN AND CENTRAL
MOUNTAINS SUNDAY AFTERNOON THROUGH TUESDAY NIGHT...

PACIFIC ENERGY KICKING OUT OF THE PACIFIC NORTHWEST FRIDAY NIGHT
WILL DRAG ACROSS THE NORTHERN ZONES AND BRING A QUICK SHOT OF SNOW
THROUGH SATURDAY MORNING. SYSTEM IS UNORGANIZED AND WILL WEAKEN AS
IT ENCOUNTERS WEAK RIDGING OVER THE REGION...LIMITING POTENTIAL
IMPACT ON OUR FORECAST AREA. THIS WAVE EXITS SATURDAY AFTERNOON
WITH A BRIEF BREAK AHEAD OF WHAT IS LOOKING LIKE A LONG
DURATION...PERSISTENTLY MOIST NORTHWESTERLY FLOW EVENT THAT
STARTS SUNDAY AFTERNOON AND CONTINUES THROUGH TUESDAY NIGHT.

MEDIUM RANGE MODELS IN GOOD AGREEMENT THIS MORNING WITH SENDING A
SERIES OF FAST MOVING WAVES THROUGH THE PACIFIC NORTHWEST WITH
ABUNDANT PACIFIC MOISTURE AND SLAMMING THIS INTO OUR NORTHERN AND
CENTRAL MOUNTAINS. SPECIFIC HUMIDITY EXCEED 3 G/KG FOR A LARGE
DURATION WITH STRONG JET SUPPORT AS A 120+ JET DRIVES THE MOISTURE
INTO OUR AREA. BASED ON CURRENT SET-UP IN THE MODELS...A PROLONGED
PERIOD OF MOIST PACIFIC FLOW AND VERY FAVORABLE OROGRAPHICS TO
BRING SUBSTANTIAL SNOWFALL OVER A 2+ DAY PERIOD BEGINNING SUNDAY
AFTERNOON. THE HEAVIEST SNOW IS EXPECTED TO FALL ACROSS THE
NORTHERN AND CENTRAL MOUNTAINS IN WESTERN COLORADO...WITH FOCUS
FROM VAIL PASS NORTHWARD TO STEAMBOAT SPRINGS. STILL TIME TO WORK
OUT THE DETAILS...BUT APPEARS WE WILL BE LOOKING AT SEVERAL WINTER
HIGHLIGHTS BY LATE THIS WEEKEND INTO EARLY NEXT WEEK.

HOWEVER...AND THERE IS ALWAYS A HOWEVER...WAA COULD AND MOST
LIKELY WILL CREATE SOME PROBLEMS WITH THE MODEL GENERATED QPF
VALUES...THUS SNOWFALL ACCUMULATIONS MAY BE OVERBLOWN. WILL GET A
BETTER HANDLE ON THIS AS THE EVENT DRAWS CLOSER. EVEN WITH THAT
CONCERN...WILL STILL BE ISSUING AN SPS LATER THIS MORNING AS THIS
WILL BE A HEAVY TRAVEL WEEK AND POTENTIAL IMPACTS COULD BE LARGE
AS SNOWFALL MAY BE MEASURED IN FEET ACROSS SOME OF OUR
MOUNTAINS...WITH THE GFS GENERATING OVER 3 FEET IN SOME AREAS BY
MIDWEEK. EVEN HALF OF THAT AMOUNT WILL CAUSE IMPACTS ON HOLIDAY
TRAVEL PLANS. OTHER AREAS WILL GET INTO THE ACTION AS WELL...BUT
THE EMPHASIS LOOKS TO BE ACROSS THE NORTHERN ZONES ATTM.
TEMPERATURES MODERATE A BIT...ESPECIALLY AS THE COLDER VALLEYS MIX
MONDAY AND TUESDAY.

AND THEN THERE IS THE POTENTIAL CHRISTMAS DAY STORM...ALTHOUGH
MODELS DIVERGE A BIT ON THIS STORM WITH THE ECMWF CLOSING A LOW
OVER THE GREAT BASIN WHEREAS THE GFS REMAINS MORE OPEN. EITHER
SOLUTION BRINGS MORE SNOW TO THE REGION...WITH THE EC MORE
FAVORABLE FOR SNOW INTO THE VALLEYS. WILL JUST RAMP POPS UP FOR
NOW WITH A COOL DOWN IN TEMPS EXPECTED.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 445 AM MST THU DEC 18 2014

WIDESPREAD IFR CIGS AND VSBYS WILL PERSIST ACROSS MUCH OF WESTERN
COLORADO THROUGH 16Z THIS MORNING...BEFORE CONDITIONS SLOWLY
IMPROVE FROM WEST TO EAST. EXPECT AREAS OF RAIN...SNOW...LOW
CLOUDS AND FOG WITH MOUNTAINS REMAINING OBSCURED. ALL TERMINAL
SITES WILL BE IMPACTED FOR SEVERAL HOURS THIS MORNING...BEFORE
CONDITIONS IMPROVED THIS AFTERNOON. THE STORM SYSTEM RESPONSIBLE
FOR THE INCLEMENT WEATHER LIFTS OUT OF THE AREA WITH MOIST
NORTHWEST FLOW KEEPING ABUNDANT CLOUD COVER IN PLACE THROUGH
TONIGHT...ALTHOUGH CIGS ARE EXPECTED TO LIFT ABOVE CAT THRESHOLDS
AT ALL SITES.


&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&

$$

UPDATE...15
SHORT TERM...JAM
LONG TERM...JDC
AVIATION...JDC





000
FXUS65 KGJT 181615
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
915 AM MST THU DEC 18 2014

.UPDATE...
ISSUED AT 910 AM MST THU DEC 18 2014

WENT AHEAD AND DROPPED THE ADVISORIES THIS MORNING WITH CLEARING
MOVING INTO THE SOUTHERN MOUNTAINS. ACROSS THE MESA INTO THE
CENTRAL COLORADO HIGH MOUNTAINS LIGHT SNOW SHOWERS AND FOG LIKELY
TO PERSIST THROUGH THE DAY THOUGH THE NATURE OF THE PRECIPITATION
WILL BECOME MORE SHOWERY. UPSTREAM ENERGY...PHASED FROM THE MORE
DEFINED SYSTEM IN ARIZONA TO THE NORTHERN ROCKIES...WILL MOVE
THROUGH THE CWA. INSTABILITY AND RESIDUAL MOISTURE SHOULD BE
ENOUGH TO KEEP ISOLATED TO SCATTERED SHOWERS IN THE PICTURE
THROUGH SUNSET. EXPECT SOME OF THE SHOWERS COULD DUMP A QUICK HALF
INCH BUT WITH COVERAGE LIMITED DO NOT EXPECT SIGNIFICANT IMPACTS
ATTM. FOG MAY BE MORE OF A PROBLEM THROUGH THE LATE MORNING HOURS
THEN AGAIN OVERNIGHT SO WILL BE MONITORING THIS AS WELL.

&&

.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 445 AM MST THU DEC 18 2014

THOUGH RETURNS ON RADAR ARE WEAK AND SATELLITE IMAGERY INDICATES
LOW CLOUD TOPS...THE SNOW IS STILL FLYING ACROSS PARTS OF WEST
CENTRAL COLORADO. AT MIDNIGHT WE RECEIVED REPORTS OF AN ONGOING
GORGE EVENT WITH 7 INCHES OF SNOW REPORTED IN THE GORGE ON HIGHWAY
550 JUST SOUTH OF OURAY BUT ONLY 3 INCHES JUST SOUTH OF THE GORGE
AREA AT RED MTN PASS. EXPECTING THIS EVENT WILL WRAP UP AROUND 6
OR 7AM AS NEGATIVE OMEGA SUPPORT SLIDES TO THE NORTH.

DEEP ATMOSPHERIC MOISTURE CONTINUES TODAY WHICH WILL KEEP THE
FORECAST AREA IN AN UNSETTLED PATTERN. THE MAIN BULK OF PRECIPITATION
IS EXPECTED TO SHIFT NORTH AND EAST TODAY AS THE WIND SHIFTS TO A
MORE WEST- NORTHWESTERLY DIRECTION...HOWEVER THE SAN JUANS WILL
STILL REMAIN SHOWERY THROUGHOUT THE DAY. UPPER LEVEL DIVERGENCE
INCREASES THIS EVENING WHICH SHOULD KEEP SHOWERS GOING INTO THE
OVERNIGHT HOURS AT HIGHER LOCATIONS. FOG WILL BE THE BIGGEST
CHALLENGE OF THE DAY AND TONIGHT AS RH REMAINS HIGH AND SURFACE
MOISTURE HAS A TOUGH TIME DRYING OUT WITH CONTINUED CLOUD COVER.

ON FRIDAY...UPPER LEVEL RIDGING BUILDS INTO THE AREA FOR A BRIEF
LULL IN ACTIVE WEATHER. TEMPERATURES WILL REMAIN NEAR NORMAL THE
NEXT COUPLE OF DAYS. THE GROUND SHOULD GET A CHANCE TO DRY OUT ON
FRIDAY DURING THE LULL OF ACTIVITY SO FOG WILL BE LESS WIDESPREAD
FRIDAY EVENING.

.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 445 AM MST THU DEC 18 2014

...SIGNIFICANT SNOWFALL POSSIBLE FOR THE NORTHERN AND CENTRAL
MOUNTAINS SUNDAY AFTERNOON THROUGH TUESDAY NIGHT...

PACIFIC ENERGY KICKING OUT OF THE PACIFIC NORTHWEST FRIDAY NIGHT
WILL DRAG ACROSS THE NORTHERN ZONES AND BRING A QUICK SHOT OF SNOW
THROUGH SATURDAY MORNING. SYSTEM IS UNORGANIZED AND WILL WEAKEN AS
IT ENCOUNTERS WEAK RIDGING OVER THE REGION...LIMITING POTENTIAL
IMPACT ON OUR FORECAST AREA. THIS WAVE EXITS SATURDAY AFTERNOON
WITH A BRIEF BREAK AHEAD OF WHAT IS LOOKING LIKE A LONG
DURATION...PERSISTENTLY MOIST NORTHWESTERLY FLOW EVENT THAT
STARTS SUNDAY AFTERNOON AND CONTINUES THROUGH TUESDAY NIGHT.

MEDIUM RANGE MODELS IN GOOD AGREEMENT THIS MORNING WITH SENDING A
SERIES OF FAST MOVING WAVES THROUGH THE PACIFIC NORTHWEST WITH
ABUNDANT PACIFIC MOISTURE AND SLAMMING THIS INTO OUR NORTHERN AND
CENTRAL MOUNTAINS. SPECIFIC HUMIDITY EXCEED 3 G/KG FOR A LARGE
DURATION WITH STRONG JET SUPPORT AS A 120+ JET DRIVES THE MOISTURE
INTO OUR AREA. BASED ON CURRENT SET-UP IN THE MODELS...A PROLONGED
PERIOD OF MOIST PACIFIC FLOW AND VERY FAVORABLE OROGRAPHICS TO
BRING SUBSTANTIAL SNOWFALL OVER A 2+ DAY PERIOD BEGINNING SUNDAY
AFTERNOON. THE HEAVIEST SNOW IS EXPECTED TO FALL ACROSS THE
NORTHERN AND CENTRAL MOUNTAINS IN WESTERN COLORADO...WITH FOCUS
FROM VAIL PASS NORTHWARD TO STEAMBOAT SPRINGS. STILL TIME TO WORK
OUT THE DETAILS...BUT APPEARS WE WILL BE LOOKING AT SEVERAL WINTER
HIGHLIGHTS BY LATE THIS WEEKEND INTO EARLY NEXT WEEK.

HOWEVER...AND THERE IS ALWAYS A HOWEVER...WAA COULD AND MOST
LIKELY WILL CREATE SOME PROBLEMS WITH THE MODEL GENERATED QPF
VALUES...THUS SNOWFALL ACCUMULATIONS MAY BE OVERBLOWN. WILL GET A
BETTER HANDLE ON THIS AS THE EVENT DRAWS CLOSER. EVEN WITH THAT
CONCERN...WILL STILL BE ISSUING AN SPS LATER THIS MORNING AS THIS
WILL BE A HEAVY TRAVEL WEEK AND POTENTIAL IMPACTS COULD BE LARGE
AS SNOWFALL MAY BE MEASURED IN FEET ACROSS SOME OF OUR
MOUNTAINS...WITH THE GFS GENERATING OVER 3 FEET IN SOME AREAS BY
MIDWEEK. EVEN HALF OF THAT AMOUNT WILL CAUSE IMPACTS ON HOLIDAY
TRAVEL PLANS. OTHER AREAS WILL GET INTO THE ACTION AS WELL...BUT
THE EMPHASIS LOOKS TO BE ACROSS THE NORTHERN ZONES ATTM.
TEMPERATURES MODERATE A BIT...ESPECIALLY AS THE COLDER VALLEYS MIX
MONDAY AND TUESDAY.

AND THEN THERE IS THE POTENTIAL CHRISTMAS DAY STORM...ALTHOUGH
MODELS DIVERGE A BIT ON THIS STORM WITH THE ECMWF CLOSING A LOW
OVER THE GREAT BASIN WHEREAS THE GFS REMAINS MORE OPEN. EITHER
SOLUTION BRINGS MORE SNOW TO THE REGION...WITH THE EC MORE
FAVORABLE FOR SNOW INTO THE VALLEYS. WILL JUST RAMP POPS UP FOR
NOW WITH A COOL DOWN IN TEMPS EXPECTED.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 445 AM MST THU DEC 18 2014

WIDESPREAD IFR CIGS AND VSBYS WILL PERSIST ACROSS MUCH OF WESTERN
COLORADO THROUGH 16Z THIS MORNING...BEFORE CONDITIONS SLOWLY
IMPROVE FROM WEST TO EAST. EXPECT AREAS OF RAIN...SNOW...LOW
CLOUDS AND FOG WITH MOUNTAINS REMAINING OBSCURED. ALL TERMINAL
SITES WILL BE IMPACTED FOR SEVERAL HOURS THIS MORNING...BEFORE
CONDITIONS IMPROVED THIS AFTERNOON. THE STORM SYSTEM RESPONSIBLE
FOR THE INCLEMENT WEATHER LIFTS OUT OF THE AREA WITH MOIST
NORTHWEST FLOW KEEPING ABUNDANT CLOUD COVER IN PLACE THROUGH
TONIGHT...ALTHOUGH CIGS ARE EXPECTED TO LIFT ABOVE CAT THRESHOLDS
AT ALL SITES.


&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&

$$

UPDATE...15
SHORT TERM...JAM
LONG TERM...JDC
AVIATION...JDC




000
FXUS65 KGJT 181146
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
446 AM MST THU DEC 18 2014

.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 445 AM MST THU DEC 18 2014

THOUGH RETURNS ON RADAR ARE WEAK AND SATELLITE IMAGERY INDICATES
LOW CLOUD TOPS...THE SNOW IS STILL FLYING ACROSS PARTS OF WEST
CENTRAL COLORADO. AT MIDNIGHT WE RECEIVED REPORTS OF AN ONGOING
GORGE EVENT WITH 7 INCHES OF SNOW REPORTED IN THE GORGE ON HIGHWAY
550 JUST SOUTH OF OURAY BUT ONLY 3 INCHES JUST SOUTH OF THE GORGE
AREA AT RED MTN PASS. EXPECTING THIS EVENT WILL WRAP UP AROUND 6
OR 7AM AS NEGATIVE OMEGA SUPPORT SLIDES TO THE NORTH.

DEEP ATMOSPHERIC MOISTURE CONTINUES TODAY WHICH WILL KEEP THE
FORECAST AREA IN AN UNSETTLED PATTERN. THE MAIN BULK OF PRECIPITATION
IS EXPECTED TO SHIFT NORTH AND EAST TODAY AS THE WIND SHIFTS TO A
MORE WEST- NORTHWESTERLY DIRECTION...HOWEVER THE SAN JUANS WILL
STILL REMAIN SHOWERY THROUGHOUT THE DAY. UPPER LEVEL DIVERGENCE
INCREASES THIS EVENING WHICH SHOULD KEEP SHOWERS GOING INTO THE
OVERNIGHT HOURS AT HIGHER LOCATIONS. FOG WILL BE THE BIGGEST
CHALLENGE OF THE DAY AND TONIGHT AS RH REMAINS HIGH AND SURFACE
MOISTURE HAS A TOUGH TIME DRYING OUT WITH CONTINUED CLOUD COVER.

ON FRIDAY...UPPER LEVEL RIDGING BUILDS INTO THE AREA FOR A BRIEF
LULL IN ACTIVE WEATHER. TEMPERATURES WILL REMAIN NEAR NORMAL THE
NEXT COUPLE OF DAYS. THE GROUND SHOULD GET A CHANCE TO DRY OUT ON
FRIDAY DURING THE LULL OF ACTIVITY SO FOG WILL BE LESS WIDESPREAD
FRIDAY EVENING.

.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 445 AM MST THU DEC 18 2014

...SIGNIFICANT SNOWFALL POSSIBLE FOR THE NORTHERN AND CENTRAL
MOUNTAINS SUNDAY AFTERNOON THROUGH TUESDAY NIGHT...

PACIFIC ENERGY KICKING OUT OF THE PACIFIC NORTHWEST FRIDAY NIGHT
WILL DRAG ACROSS THE NORTHERN ZONES AND BRING A QUICK SHOT OF SNOW
THROUGH SATURDAY MORNING. SYSTEM IS UNORGANIZED AND WILL WEAKEN AS
IT ENCOUNTERS WEAK RIDGING OVER THE REGION...LIMITING POTENTIAL
IMPACT ON OUR FORECAST AREA. THIS WAVE EXITS SATURDAY AFTERNOON
WITH A BRIEF BREAK AHEAD OF WHAT IS LOOKING LIKE A LONG
DURATION...PERSISTENTLY MOIST NORTHWESTERLY FLOW EVENT THAT
STARTS SUNDAY AFTERNOON AND CONTINUES THROUGH TUESDAY NIGHT.

MEDIUM RANGE MODELS IN GOOD AGREEMENT THIS MORNING WITH SENDING A
SERIES OF FAST MOVING WAVES THROUGH THE PACIFIC NORTHWEST WITH
ABUNDANT PACIFIC MOISTURE AND SLAMMING THIS INTO OUR NORTHERN AND
CENTRAL MOUNTAINS. SPECIFIC HUMIDITY EXCEED 3 G/KG FOR A LARGE
DURATION WITH STRONG JET SUPPORT AS A 120+ JET DRIVES THE MOISTURE
INTO OUR AREA. BASED ON CURRENT SET-UP IN THE MODELS...A PROLONGED
PERIOD OF MOIST PACIFIC FLOW AND VERY FAVORABLE OROGRAPHICS TO
BRING SUBSTANTIAL SNOWFALL OVER A 2+ DAY PERIOD BEGINNING SUNDAY
AFTERNOON. THE HEAVIEST SNOW IS EXPECTED TO FALL ACROSS THE
NORTHERN AND CENTRAL MOUNTAINS IN WESTERN COLORADO...WITH FOCUS
FROM VAIL PASS NORTHWARD TO STEAMBOAT SPRINGS. STILL TIME TO WORK
OUT THE DETAILS...BUT APPEARS WE WILL BE LOOKING AT SEVERAL WINTER
HIGHLIGHTS BY LATE THIS WEEKEND INTO EARLY NEXT WEEK.

HOWEVER...AND THERE IS ALWAYS A HOWEVER...WAA COULD AND MOST
LIKELY WILL CREATE SOME PROBLEMS WITH THE MODEL GENERATED QPF
VALUES...THUS SNOWFALL ACCUMULATIONS MAY BE OVERBLOWN. WILL GET A
BETTER HANDLE ON THIS AS THE EVENT DRAWS CLOSER. EVEN WITH THAT
CONCERN...WILL STILL BE ISSUING AN SPS LATER THIS MORNING AS THIS
WILL BE A HEAVY TRAVEL WEEK AND POTENTIAL IMPACTS COULD BE LARGE
AS SNOWFALL MAY BE MEASURED IN FEET ACROSS SOME OF OUR
MOUNTAINS...WITH THE GFS GENERATING OVER 3 FEET IN SOME AREAS BY
MIDWEEK. EVEN HALF OF THAT AMOUNT WILL CAUSE IMPACTS ON HOLIDAY
TRAVEL PLANS. OTHER AREAS WILL GET INTO THE ACTION AS WELL...BUT
THE EMPHASIS LOOKS TO BE ACROSS THE NORTHERN ZONES ATTM.
TEMPERATURES MODERATE A BIT...ESPECIALLY AS THE COLDER VALLEYS MIX
MONDAY AND TUESDAY.

AND THEN THERE IS THE POTENTIAL CHRISTMAS DAY STORM...ALTHOUGH
MODELS DIVERGE A BIT ON THIS STORM WITH THE ECMWF CLOSING A LOW
OVER THE GREAT BASIN WHEREAS THE GFS REMAINS MORE OPEN. EITHER
SOLUTION BRINGS MORE SNOW TO THE REGION...WITH THE EC MORE
FAVORABLE FOR SNOW INTO THE VALLEYS. WILL JUST RAMP POPS UP FOR
NOW WITH A COOL DOWN IN TEMPS EXPECTED.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 445 AM MST THU DEC 18 2014

WIDESPREAD IFR CIGS AND VSBYS WILL PERSIST ACROSS MUCH OF WESTERN
COLORADO THROUGH 16Z THIS MORNING...BEFORE CONDITIONS SLOWLY
IMPROVE FROM WEST TO EAST. EXPECT AREAS OF RAIN...SNOW...LOW
CLOUDS AND FOG WITH MOUNTAINS REMAINING OBSCURED. ALL TERMINAL
SITES WILL BE IMPACTED FOR SEVERAL HOURS THIS MORNING...BEFORE
CONDITIONS IMPROVED THIS AFTERNOON. THE STORM SYSTEM RESPONSIBLE
FOR THE INCLEMENT WEATHER LIFTS OUT OF THE AREA WITH MOIST
NORTHWEST FLOW KEEPING ABUNDANT CLOUD COVER IN PLACE THROUGH
TONIGHT...ALTHOUGH CIGS ARE EXPECTED TO LIFT ABOVE CAT THRESHOLDS
AT ALL SITES.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL 9 AM MST THIS MORNING FOR COZ009-
     018.

UT...NONE.
&&

$$

SHORT TERM...JAM
LONG TERM...JDC
AVIATION...JDC




000
FXUS65 KGJT 181146
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
446 AM MST THU DEC 18 2014

.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 445 AM MST THU DEC 18 2014

THOUGH RETURNS ON RADAR ARE WEAK AND SATELLITE IMAGERY INDICATES
LOW CLOUD TOPS...THE SNOW IS STILL FLYING ACROSS PARTS OF WEST
CENTRAL COLORADO. AT MIDNIGHT WE RECEIVED REPORTS OF AN ONGOING
GORGE EVENT WITH 7 INCHES OF SNOW REPORTED IN THE GORGE ON HIGHWAY
550 JUST SOUTH OF OURAY BUT ONLY 3 INCHES JUST SOUTH OF THE GORGE
AREA AT RED MTN PASS. EXPECTING THIS EVENT WILL WRAP UP AROUND 6
OR 7AM AS NEGATIVE OMEGA SUPPORT SLIDES TO THE NORTH.

DEEP ATMOSPHERIC MOISTURE CONTINUES TODAY WHICH WILL KEEP THE
FORECAST AREA IN AN UNSETTLED PATTERN. THE MAIN BULK OF PRECIPITATION
IS EXPECTED TO SHIFT NORTH AND EAST TODAY AS THE WIND SHIFTS TO A
MORE WEST- NORTHWESTERLY DIRECTION...HOWEVER THE SAN JUANS WILL
STILL REMAIN SHOWERY THROUGHOUT THE DAY. UPPER LEVEL DIVERGENCE
INCREASES THIS EVENING WHICH SHOULD KEEP SHOWERS GOING INTO THE
OVERNIGHT HOURS AT HIGHER LOCATIONS. FOG WILL BE THE BIGGEST
CHALLENGE OF THE DAY AND TONIGHT AS RH REMAINS HIGH AND SURFACE
MOISTURE HAS A TOUGH TIME DRYING OUT WITH CONTINUED CLOUD COVER.

ON FRIDAY...UPPER LEVEL RIDGING BUILDS INTO THE AREA FOR A BRIEF
LULL IN ACTIVE WEATHER. TEMPERATURES WILL REMAIN NEAR NORMAL THE
NEXT COUPLE OF DAYS. THE GROUND SHOULD GET A CHANCE TO DRY OUT ON
FRIDAY DURING THE LULL OF ACTIVITY SO FOG WILL BE LESS WIDESPREAD
FRIDAY EVENING.

.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 445 AM MST THU DEC 18 2014

...SIGNIFICANT SNOWFALL POSSIBLE FOR THE NORTHERN AND CENTRAL
MOUNTAINS SUNDAY AFTERNOON THROUGH TUESDAY NIGHT...

PACIFIC ENERGY KICKING OUT OF THE PACIFIC NORTHWEST FRIDAY NIGHT
WILL DRAG ACROSS THE NORTHERN ZONES AND BRING A QUICK SHOT OF SNOW
THROUGH SATURDAY MORNING. SYSTEM IS UNORGANIZED AND WILL WEAKEN AS
IT ENCOUNTERS WEAK RIDGING OVER THE REGION...LIMITING POTENTIAL
IMPACT ON OUR FORECAST AREA. THIS WAVE EXITS SATURDAY AFTERNOON
WITH A BRIEF BREAK AHEAD OF WHAT IS LOOKING LIKE A LONG
DURATION...PERSISTENTLY MOIST NORTHWESTERLY FLOW EVENT THAT
STARTS SUNDAY AFTERNOON AND CONTINUES THROUGH TUESDAY NIGHT.

MEDIUM RANGE MODELS IN GOOD AGREEMENT THIS MORNING WITH SENDING A
SERIES OF FAST MOVING WAVES THROUGH THE PACIFIC NORTHWEST WITH
ABUNDANT PACIFIC MOISTURE AND SLAMMING THIS INTO OUR NORTHERN AND
CENTRAL MOUNTAINS. SPECIFIC HUMIDITY EXCEED 3 G/KG FOR A LARGE
DURATION WITH STRONG JET SUPPORT AS A 120+ JET DRIVES THE MOISTURE
INTO OUR AREA. BASED ON CURRENT SET-UP IN THE MODELS...A PROLONGED
PERIOD OF MOIST PACIFIC FLOW AND VERY FAVORABLE OROGRAPHICS TO
BRING SUBSTANTIAL SNOWFALL OVER A 2+ DAY PERIOD BEGINNING SUNDAY
AFTERNOON. THE HEAVIEST SNOW IS EXPECTED TO FALL ACROSS THE
NORTHERN AND CENTRAL MOUNTAINS IN WESTERN COLORADO...WITH FOCUS
FROM VAIL PASS NORTHWARD TO STEAMBOAT SPRINGS. STILL TIME TO WORK
OUT THE DETAILS...BUT APPEARS WE WILL BE LOOKING AT SEVERAL WINTER
HIGHLIGHTS BY LATE THIS WEEKEND INTO EARLY NEXT WEEK.

HOWEVER...AND THERE IS ALWAYS A HOWEVER...WAA COULD AND MOST
LIKELY WILL CREATE SOME PROBLEMS WITH THE MODEL GENERATED QPF
VALUES...THUS SNOWFALL ACCUMULATIONS MAY BE OVERBLOWN. WILL GET A
BETTER HANDLE ON THIS AS THE EVENT DRAWS CLOSER. EVEN WITH THAT
CONCERN...WILL STILL BE ISSUING AN SPS LATER THIS MORNING AS THIS
WILL BE A HEAVY TRAVEL WEEK AND POTENTIAL IMPACTS COULD BE LARGE
AS SNOWFALL MAY BE MEASURED IN FEET ACROSS SOME OF OUR
MOUNTAINS...WITH THE GFS GENERATING OVER 3 FEET IN SOME AREAS BY
MIDWEEK. EVEN HALF OF THAT AMOUNT WILL CAUSE IMPACTS ON HOLIDAY
TRAVEL PLANS. OTHER AREAS WILL GET INTO THE ACTION AS WELL...BUT
THE EMPHASIS LOOKS TO BE ACROSS THE NORTHERN ZONES ATTM.
TEMPERATURES MODERATE A BIT...ESPECIALLY AS THE COLDER VALLEYS MIX
MONDAY AND TUESDAY.

AND THEN THERE IS THE POTENTIAL CHRISTMAS DAY STORM...ALTHOUGH
MODELS DIVERGE A BIT ON THIS STORM WITH THE ECMWF CLOSING A LOW
OVER THE GREAT BASIN WHEREAS THE GFS REMAINS MORE OPEN. EITHER
SOLUTION BRINGS MORE SNOW TO THE REGION...WITH THE EC MORE
FAVORABLE FOR SNOW INTO THE VALLEYS. WILL JUST RAMP POPS UP FOR
NOW WITH A COOL DOWN IN TEMPS EXPECTED.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 445 AM MST THU DEC 18 2014

WIDESPREAD IFR CIGS AND VSBYS WILL PERSIST ACROSS MUCH OF WESTERN
COLORADO THROUGH 16Z THIS MORNING...BEFORE CONDITIONS SLOWLY
IMPROVE FROM WEST TO EAST. EXPECT AREAS OF RAIN...SNOW...LOW
CLOUDS AND FOG WITH MOUNTAINS REMAINING OBSCURED. ALL TERMINAL
SITES WILL BE IMPACTED FOR SEVERAL HOURS THIS MORNING...BEFORE
CONDITIONS IMPROVED THIS AFTERNOON. THE STORM SYSTEM RESPONSIBLE
FOR THE INCLEMENT WEATHER LIFTS OUT OF THE AREA WITH MOIST
NORTHWEST FLOW KEEPING ABUNDANT CLOUD COVER IN PLACE THROUGH
TONIGHT...ALTHOUGH CIGS ARE EXPECTED TO LIFT ABOVE CAT THRESHOLDS
AT ALL SITES.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL 9 AM MST THIS MORNING FOR COZ009-
     018.

UT...NONE.
&&

$$

SHORT TERM...JAM
LONG TERM...JDC
AVIATION...JDC





000
FXUS65 KGJT 180545
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1045 PM MST WED DEC 17 2014

.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 341 PM MST WED DEC 17 2014

ACCUMULATIONS WERE LIGHT IN THE SOUTHERN MTNS TODAY BUT WERE
PICKING UP IN COVERAGE IN THE AFTERNOON. MID AFTERNOON SNOTELS
INDICATED TRACE TO 3 INCH ACCUMULATIONS...WITH ONE INCH REPORTED
IN SILVERTON. RADAR HAS SHOWED SOME SUSTAINED ENHANCEMENT OVER THE
LA SAL MTNS THIS AFTERNOON.

DISORGANIZED SYSTEM IS WORKING THROUGH NORTHERN NEW MEXICO THIS
AFTERNOON WITH WEAK RIDGING EXPECTED OVERNIGHT. THE KEY TO THE
WEATHER IS THE DEEP MOISTURE THAT IS IN PLACE AND WILL REMAIN
OVER THE AREA THROUGH THURSDAY NIGHT. SOME ACCUMULATIONS ARE
EXPECTED OVER THE SOUTHERN- CENTRAL MTNS THIS AFTERNOON SO HAVE
LEFT ADVISORIES IN PLACE INTO THE EARLY MORNING HOURS.

SOUTHERN MTN SNOW WILL CONTINUE ON THURSDAY AS THE NEXT OPEN WAVE
WORKS THROUGH SOUTHERN AZ-NM. SNOW ACCUMULATIONS LOOK TO BE LIGHT
WITH LITTLE IMPACT.

THE MOST IMPACTFUL WEATHER IS EXPECTED TO BE WIDESPREAD FOG
TONIGHT THROUGH THURSDAY NIGHT. MOUNTAIN FOG THIS AFTERNOON WILL
SETTLE INTO MOST VALLEYS OVERNIGHT AND INTO THURSDAY MORNING.
DENSE FOG ADVISORIES MAY BE NEEDED FAVORING THE SOUTH AND CENTRAL
FORECAST AREA. FOG AGAIN IS EXPECTED THURSDAY NIGHT. ALL THIS
MOISTURE KEEPS TEMPERATURES MILD FOR MID DECEMBER.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 341 PM MST WED DEC 17 2014

A TRANSITORY SHORT WAVE RIDGE WORKS ACROSS THE INTERMOUNTAIN WEST TO
THE HIGH PLAINS FRIDAY AND FRIDAY NIGHT...PUSHED ALONG BY THE
ARRIVAL OF THE STRONG PACIFIC JET TO THE NORTHWEST COAST. MOISTURE
PROFILES ARE NOT VERY FAVORABLE FOR SIGNIFICANT SNOW WITH THE BULK
OF THE DENDRITIC LAYER STAYING UNSATURATED. HOWEVER CROSS SECTIONS
SUGGESTS MOISTURE LINGERING NEAR MOUNTAIN TOP LEVEL WHICH COULD LEAD
TO SOME LIGHT SNOW SHOWERS LINGERING AROUND THE NORTHERN MOUNTAINS
DURING THIS TIME FRAME. CONFIDENCE LIKE POPS WILL BE ON THE VERY LOW
SIDE. 300K THETA SURFACES SHOW A STRONG PUSH OF MOISTURE INTO THE
NORTHWEST STATES EARLY THIS WEEKEND...REACHING OUR NORTHERN CWA BY
EARLY SUNDAY MORNING. THE ARRIVAL OF THE MOISTURE WILL COINCIDE WITH
130+KT CORE NOSING INTO NORTHWEST CORNER OF THE CONUS. MUCH OF THE
UPSTREAM TERRAIN WILL BE ALLOWED TO SOAK UP THIS MOISTURE WITH THE
MAIN STORM TRACK AND DYNAMICS STAY JUST TO OUR NORTH THROUGH SUNDAY.
OUR NORTHERN MOUNTAINS DOWN TO NEAR VAIL PASS WILL BE BRUSHED WITH
MOISTURE AND WILL RELY ON INCREASING OROGRAPHICS TO PRODUCE A
PROLONGED PERIOD OF LIGHT SNOW. THE OROGRAPHICS WILL BE
SUPPLEMENTED BY JET DYNAMICS AND A CONSTANT STREAM OF CHANNELIZED
VORTICITY EARLY MONDAY THROUGH TUESDAY AFTERNOON. PRECIPITABLE
WATER INCREASES TO NEAR 0.5 INCHES...WELL ABOVE NORMAL FOR LATE
DECEMBER OVER OUR NORTHERN CWA. THE INCREASE IN LARGE SCALE
ASCENT...MOISTURE AND WINDS ALOFT SHOULD SPREAD SNOW TO A WIDER
AUDIENCE MONDAY INTO TUESDAY. THE ONLY CONCERN WILL BE WARM AIR
MOVING IN ALOFT AND CHANGING THE DENDRITIC AND POSSIBLY THE
OROGRAPHICS MONDAY...BUT BY MONDAY NIGHT ALL INGREDIENTS APPEAR TO
BE THERE FOR SIGNIFICANT SNOW ACROSS NORTHWEST COLORADO AND
PORTIONS OF THE CENTRAL MOUNTAINS. STRONG RIDGING IN THE EAST
PACIFIC AND A DEEP NEGATIVELY TILTED TROUGH IN THE EAST KEEPS
MOIST NORTHWEST FLOW IN PLACE THROUGH MID- WEEK. THE LONGER TERM
MODELS ARE BEGINNING TO CONVERGE ON A HIGH LATITUDE SYSTEM
DROPPING INTO THE INTERMOUNTAIN WEST WHICH COULD BRING WIDESPREAD
PRECIPITATION TO OUR CWA BY IN TIME FOR THE HOLIDAYS. FOR THE MOST
PART TEMPERATURES WILL BE NEAR TO SLIGHTLY BELOW NORMAL DURING
THIS ACTIVE PERIOD.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1037 PM MST WED DEC 17 2014

EXPECT WIDESPREAD MTN OBSCURATIONS TO CONTINUE OVERNIGHT FROM THE
CENTRAL MOUNTAINS SOUTHWARD. LOWERED CIGS WILL BE COMMON AT MANY
LOCATIONS EITHER DUE TO -SN AND FG OR JUST REDUCED VIS DUE TO BR.
LOCALLY DENSE FOG IS POSSIBLE BY THURS AM BUT CONFIDENCE IS NOT
HIGH ON WHETHER IT WILL AFFECT ANY TAF SITES. FOG IS EXPECTED TO
BREAK BY 19Z THURSDAY...THOUGH DECENT MOISTURE WILL CONTINUE TO
PLAGUE THE REGION THROUGH THURS NIGHT...ALLOWING ISOLATED SHOWERS
TO CONTINUE THROUGHOUT THE DAY. SHOWERS ON THURS WILL REMAIN
MAINLY OVER THE MTNS SO MTN OBSCURATIONS WILL STILL BE COMMON
THROUGHOUT THE DAY.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL 3 AM MST THURSDAY FOR COZ009-018-
     019.

UT...NONE.
&&

$$

SHORT TERM...JOE
LONG TERM...15
AVIATION...JAM





000
FXUS65 KGJT 180545
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1045 PM MST WED DEC 17 2014

.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 341 PM MST WED DEC 17 2014

ACCUMULATIONS WERE LIGHT IN THE SOUTHERN MTNS TODAY BUT WERE
PICKING UP IN COVERAGE IN THE AFTERNOON. MID AFTERNOON SNOTELS
INDICATED TRACE TO 3 INCH ACCUMULATIONS...WITH ONE INCH REPORTED
IN SILVERTON. RADAR HAS SHOWED SOME SUSTAINED ENHANCEMENT OVER THE
LA SAL MTNS THIS AFTERNOON.

DISORGANIZED SYSTEM IS WORKING THROUGH NORTHERN NEW MEXICO THIS
AFTERNOON WITH WEAK RIDGING EXPECTED OVERNIGHT. THE KEY TO THE
WEATHER IS THE DEEP MOISTURE THAT IS IN PLACE AND WILL REMAIN
OVER THE AREA THROUGH THURSDAY NIGHT. SOME ACCUMULATIONS ARE
EXPECTED OVER THE SOUTHERN- CENTRAL MTNS THIS AFTERNOON SO HAVE
LEFT ADVISORIES IN PLACE INTO THE EARLY MORNING HOURS.

SOUTHERN MTN SNOW WILL CONTINUE ON THURSDAY AS THE NEXT OPEN WAVE
WORKS THROUGH SOUTHERN AZ-NM. SNOW ACCUMULATIONS LOOK TO BE LIGHT
WITH LITTLE IMPACT.

THE MOST IMPACTFUL WEATHER IS EXPECTED TO BE WIDESPREAD FOG
TONIGHT THROUGH THURSDAY NIGHT. MOUNTAIN FOG THIS AFTERNOON WILL
SETTLE INTO MOST VALLEYS OVERNIGHT AND INTO THURSDAY MORNING.
DENSE FOG ADVISORIES MAY BE NEEDED FAVORING THE SOUTH AND CENTRAL
FORECAST AREA. FOG AGAIN IS EXPECTED THURSDAY NIGHT. ALL THIS
MOISTURE KEEPS TEMPERATURES MILD FOR MID DECEMBER.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 341 PM MST WED DEC 17 2014

A TRANSITORY SHORT WAVE RIDGE WORKS ACROSS THE INTERMOUNTAIN WEST TO
THE HIGH PLAINS FRIDAY AND FRIDAY NIGHT...PUSHED ALONG BY THE
ARRIVAL OF THE STRONG PACIFIC JET TO THE NORTHWEST COAST. MOISTURE
PROFILES ARE NOT VERY FAVORABLE FOR SIGNIFICANT SNOW WITH THE BULK
OF THE DENDRITIC LAYER STAYING UNSATURATED. HOWEVER CROSS SECTIONS
SUGGESTS MOISTURE LINGERING NEAR MOUNTAIN TOP LEVEL WHICH COULD LEAD
TO SOME LIGHT SNOW SHOWERS LINGERING AROUND THE NORTHERN MOUNTAINS
DURING THIS TIME FRAME. CONFIDENCE LIKE POPS WILL BE ON THE VERY LOW
SIDE. 300K THETA SURFACES SHOW A STRONG PUSH OF MOISTURE INTO THE
NORTHWEST STATES EARLY THIS WEEKEND...REACHING OUR NORTHERN CWA BY
EARLY SUNDAY MORNING. THE ARRIVAL OF THE MOISTURE WILL COINCIDE WITH
130+KT CORE NOSING INTO NORTHWEST CORNER OF THE CONUS. MUCH OF THE
UPSTREAM TERRAIN WILL BE ALLOWED TO SOAK UP THIS MOISTURE WITH THE
MAIN STORM TRACK AND DYNAMICS STAY JUST TO OUR NORTH THROUGH SUNDAY.
OUR NORTHERN MOUNTAINS DOWN TO NEAR VAIL PASS WILL BE BRUSHED WITH
MOISTURE AND WILL RELY ON INCREASING OROGRAPHICS TO PRODUCE A
PROLONGED PERIOD OF LIGHT SNOW. THE OROGRAPHICS WILL BE
SUPPLEMENTED BY JET DYNAMICS AND A CONSTANT STREAM OF CHANNELIZED
VORTICITY EARLY MONDAY THROUGH TUESDAY AFTERNOON. PRECIPITABLE
WATER INCREASES TO NEAR 0.5 INCHES...WELL ABOVE NORMAL FOR LATE
DECEMBER OVER OUR NORTHERN CWA. THE INCREASE IN LARGE SCALE
ASCENT...MOISTURE AND WINDS ALOFT SHOULD SPREAD SNOW TO A WIDER
AUDIENCE MONDAY INTO TUESDAY. THE ONLY CONCERN WILL BE WARM AIR
MOVING IN ALOFT AND CHANGING THE DENDRITIC AND POSSIBLY THE
OROGRAPHICS MONDAY...BUT BY MONDAY NIGHT ALL INGREDIENTS APPEAR TO
BE THERE FOR SIGNIFICANT SNOW ACROSS NORTHWEST COLORADO AND
PORTIONS OF THE CENTRAL MOUNTAINS. STRONG RIDGING IN THE EAST
PACIFIC AND A DEEP NEGATIVELY TILTED TROUGH IN THE EAST KEEPS
MOIST NORTHWEST FLOW IN PLACE THROUGH MID- WEEK. THE LONGER TERM
MODELS ARE BEGINNING TO CONVERGE ON A HIGH LATITUDE SYSTEM
DROPPING INTO THE INTERMOUNTAIN WEST WHICH COULD BRING WIDESPREAD
PRECIPITATION TO OUR CWA BY IN TIME FOR THE HOLIDAYS. FOR THE MOST
PART TEMPERATURES WILL BE NEAR TO SLIGHTLY BELOW NORMAL DURING
THIS ACTIVE PERIOD.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1037 PM MST WED DEC 17 2014

EXPECT WIDESPREAD MTN OBSCURATIONS TO CONTINUE OVERNIGHT FROM THE
CENTRAL MOUNTAINS SOUTHWARD. LOWERED CIGS WILL BE COMMON AT MANY
LOCATIONS EITHER DUE TO -SN AND FG OR JUST REDUCED VIS DUE TO BR.
LOCALLY DENSE FOG IS POSSIBLE BY THURS AM BUT CONFIDENCE IS NOT
HIGH ON WHETHER IT WILL AFFECT ANY TAF SITES. FOG IS EXPECTED TO
BREAK BY 19Z THURSDAY...THOUGH DECENT MOISTURE WILL CONTINUE TO
PLAGUE THE REGION THROUGH THURS NIGHT...ALLOWING ISOLATED SHOWERS
TO CONTINUE THROUGHOUT THE DAY. SHOWERS ON THURS WILL REMAIN
MAINLY OVER THE MTNS SO MTN OBSCURATIONS WILL STILL BE COMMON
THROUGHOUT THE DAY.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL 3 AM MST THURSDAY FOR COZ009-018-
     019.

UT...NONE.
&&

$$

SHORT TERM...JOE
LONG TERM...15
AVIATION...JAM




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