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000
FXUS65 KGJT 011030
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
330 AM MST SAT MAR 1 2014

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 330 AM MST SAT MAR 1 2014

A WELL-DEFINED UPPER LOW WAS JUST OFF THE CENTRAL CA COAST EARLY
THIS MORNING. LEAD UPPER JET MAX EJECTING ACROSS AZ INTO SRN UT
WAS GENERATING A BAND OF MODERATE PRECIPITATION FROM AZ ACROSS
MUCH OF UT...WITH PRECIPITATION WORKING INTO WRN CO. SOME
THUNDERSTORMS PERSISTED IN AZ...WITH A LIGHTNING STRIKE NOTED IN
SE UT AT 230 AM. A COLD FRONT WAS DRAPED ACROSS WY AND DOWN THE
FRONT RANGE IN ERN CO AND SHOULD REMAIN TO OUR NORTH AND EAST.

MODELS ALL IN GOOD AGREEMENT ON TRACKING THE UPPER LOW ACROSS SRN CA
TODAY AND HAVE MADE LITTLE CHANGE TO THE GOING FORECAST GRIDS. THE
EJECTING JET MAX MOVES OVER ERN UT AND ACROSS WRN CO THIS MORNING.
BEST PRECIPITATION POTENTIAL LOOKS TO BE PRIOR TO 18Z THIS MORNING
WHEN DYNAMIC LIFT COUPLES WITH DEEP LAYER PACIFIC MOISTURE IN
STRONG SOUTHWEST OROGRAPHIC FLOW. WINDS WILL BE GUSTY AT
TIMES...WITH LOCALIZED GUSTS UP TO 40 MPH. GUSTS TO 70-80 MPH WERE
MEASURED BY AUTOMATED STATIONS ABOVE 11K-12K FEET IN THE SAN JUANS.

THE SOUTHWEST FLOW WAS PUSHING WARM AIR INTO THE FORECAST REGION
WITH GRAND JCT AT 47 DEGREES AT 3 AM. SNOW LEVELS CONTINUE TO BE A
CHALLENGE WITH RAIN AT ASPEN BUT SNOW AT VAIL PASS AND TELLURIDE.
SNOW LEVELS WILL LOWER OVER THE COURSE OF TODAY AS THE COLD POOL ALOFT
APPROACHES. LAPSE RATES ALSO STEEPEN AS A RESULT OF COLD ADVECTION
ALOFT FOR MORE SHOWERY PRECIPITATION THIS AFTERNOON. KEPT THE
POSSIBILITY OF ISOLATED THUNDERSTORMS IN THE FORECAST FOR MUCH OF
THE AREA TODAY WITH MARGINAL CAPE AND A LIFTED INDEX NEAR ZERO.

THE CLOSED LOW QUICKLY EVOLVES INTO AN OPEN WAVE TONIGHT AS THE LEAD
JET PULLS AWAY. THE RESULTANT TROUGH AXIS PASSES ABOUT 12Z SUNDAY
MORNING WITH THE BEST Q-G FORCING REMAINING SOUTH OF THE FOUR
CORNERS. SOUTHWEST FLOW TURNS MORE WESTERLY LATE TONIGHT AND SUNDAY
AND OROGRAPHICALLY MORE FAVORABLE FOR THE NORTHERN MTNS...BUT THE
GREATEST MOISTURE WILL ALSO BE MOVING OUT OF THE AREA. HAVE NOT MADE
ANY CHANGES TO THE CURRENT WINTER HIGHLIGHTS...BUT PRECIPITATION MAY
BE DIMINISHING ACROSS ERN UT ON SUNDAY QUICKER THAN THE HIGHLIGHTS
CURRENTLY INDICATE IF THE CURRENT MODEL TREND HOLDS.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 330 AM MST SAT MAR 1 2014

MODELS IN GOOD AGREEMENT THAT THE JET STREAM WILL HAVE SHIFTED
WELL TO OUR EAST ALONG WITH THE UPPER LEVEL TROUGH CAUSING MOST
PRECIP TO END SUNDAY EVENING INTO SUNDAY NIGHT SO NO CHANGE TO
END TIME WITH CURRENT HIGHLIGHTS. BY MONDAY MORNING...NAM12 DOES
SHOW SOME LIGHT QPF OVER CONTINENTAL DIVIDE AND WITH FAVORABLE
NWLY FLOW...THIS IS CERTAINLY POSSIBLE SO LOW END POPS REMAIN IN
FORECAST FOR THIS CHANCE.

FOR MUCH OF THE REMAINING FORECAST PERIOD...MOISTURE WILL STREAM
IN FROM THE PACIFIC BUT THIS TIME THE PACNW IS FAVORED WITH PLENTY
OF PRECIP EXPECTED FOR THAT REGION. AS FAR AS OUR CWA IS
CONCERNED...SEVERAL SMALL PIECES OF ENERGY WILL MOVE OVER THE AREA
FROM TIME TO TIME CAUSING UNSETTLED WX. PRESENTLY...EC FAVORS A
MORE WIDESPREAD PATTERN OF PRECIP MONDAY AFTN...TUESDAY NIGHT INTO
WED MORNING AND AGAIN ON FRIDAY. IF THE GFS IS TO BE BELIEVED...A
QUICK SHOT OF PRECIP WILL MOVE IN EARLY WED MORNING AND AGAIN THUR
MORNING INTO FRIDAY. THE GFS DOES FAVOR AREAS N OF I-70 FOR EACH
SHOT OF PRECIP. WITH SUCH DIFFERENCES IN MODELS...HARD TO REALLY NAIL
DOWN SPECIFICS AT THIS TIME. DID LEAN SLIGHTLY MORE TOWARDS GFS
MONDAY INTO TUESDAY AS IT HAS BEEN SLIGHTLY MORE CONSISTENT BUT
BLENDED SOLNS LOOK GOOD AFTER THAT WITH SCHC TO CHC PRECIP FOR
EACH PASSING DISTURBANCE. WITH THICKNESS VALUES SHOWING NO REAL
FRONTS MOVING THROUGH THE AREA UNTIL FRIDAY...MOS GUIDANCE SHOWING
TEMPS RUNNING A LITTLE ABOVE NORMAL LOOKS GOOD.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 330 AM MST SAT MAR 1 2014

EXPECT WIDESPREAD MVFR TO VLIFR FOR THE NEXT 24 HOURS AS THE NEXT
SYSTEM MOVES OVER THE AREA BRINGING RA TO THE LOWER ELEVATIONS AND
SN FOR HIGHER ELEVATIONS. OCCNL +RA AND +SN IS EXPECTED TODAY. THE
WORST CONDITIONS WILL OCCUR FROM 12Z THIS MORNING THROUGH 00Z THIS
EVENING AS A COLD FRONT MOVES ACROSS THE REGION. ISOLATED STORMS
ARE ALSO EXPECTED WITH THE PASSAGE OF THIS FRONT AS ARE SOME GUSTY
SURFACE WINDS. VALLEYS CAN EXPECT TO SEE GUSTS OF 30 TO 35 MPH
THROUGH THE DAY WHILE ELEVATIONS ABOUT 10K FEET WILL SEE GUSTS
REACHING 50 MPH AND HIGHER. TURBULENCE WILL BE COMMON NEAR
MOUNTAINOUS TERRAIN WITH ALMOST ALL MOUNTAIN TOPS BEING OBSCURED.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...WINTER WEATHER ADVISORY UNTIL 9 PM MST SUNDAY ABOVE 7500 FEET
     FOR THE COZ003.

     WINTER WEATHER ADVISORY UNTIL 9 PM MST SUNDAY COZ014.
     WINTER STORM WARNING UNTIL 9 PM MST SUNDAY
     COZ009-010-012-013-018-019.
     WINTER STORM WARNING UNTIL 9 PM MST SUNDAY COZ017.
     WINTER WEATHER ADVISORY UNTIL NOON MST SUNDAY ABOVE 7000 FEET
     FOR THE COZ023.
     WINTER WEATHER ADVISORY UNTIL 9 PM MST SUNDAY COZ004.
     WINTER WEATHER ADVISORY UNTIL 9 PM MST SUNDAY ABOVE 7000 FEET
     FOR THE COZ008.

UT...WINTER WEATHER ADVISORY UNTIL 9 PM MST SUNDAY ABOVE 7500 FEET
     FOR THE UTZ023-025.

     WINTER STORM WARNING UNTIL 9 PM MST SUNDAY ABOVE 7500 FEET FOR
     THE UTZ028.

&&

$$

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