000
FXUS65 KGJT 121654
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
954 AM MST THU DEC 12 2013

.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 255 AM MST THU DEC 12 2013

STRONG INVERSIONS REMAIN THE MAIN WEATHER STORY. ONLY THE SOUTHERN
VALLEYS WILL GET ANY VERTICAL MIXING AT ALL. STILL WITH WEAK
RIDGING OVER THE REGION TODAY THE MOUNTAIN SLOPES WILL HAVE MILD
TEMPS IN THE 20S TO MID 30S.

VALLEY FOG MAY BECOME MORE PREVALENT TONIGHT. THE VALLEYS ARE
TRAPPING MORE AND MORE POLLUTANTS THAT MAY SERVE AS CONDENSATION
NUCLEI FOR INCREASED FOG FORMATION. FOG IS MOST LIKELY ALONG RIVER
COURSES AND THE LOWEST VALLEY ELEVATIONS... BUT ICE FOG IS ALWAYS
NUANCED AND A CHALLENGE TO PREDICT.

TONIGHT MID-HIGH CLOUDS WILL SPREAD INTO THE FOUR CORNERS REGION.
A WEAK UPPER LOW WILL OPEN OVER ARIZONA TONIGHT THEN TRACK THROUGH
NEW MEXICO ON FRIDAY. THIS MAY PRODUCE SOME LIGHT SHOWERS JUST
NORTH OF THE AZ- NM BORDER. AS THE SOUTHERN LOW PASSES FRIDAY
AFTERNOON A STRONGER TROUGH APPROACHES FROM THE NW. THIS THREATENS
SCATTERED LIGHT SNOW IN THE NORTHERN MTNS BY LATE AFTERNOON.

.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 255 AM MST THU DEC 12 2013

MOISTURE STARVED WAVE WILL BE DROPPING SOME LIGHT SNOW ACROSS THE
NORTHERN AND CENTRAL MOUNTAINS FRIDAY EVENING. ADDITIONAL WEAK
RIPPLES SLIDE ACROSS EVERY 12 TO 18 HOURS THROUGH EARLY MONDAY.
SNOWFALL AMOUNTS WITH THE LEAD SYSTEM APPEAR TO BE UNDER 4
INCHES...WITH THE HEAVIEST ACCUMULATIONS EXPECTED ACROSS THE PARK
RANGE NEAR STEAMBOAT SPRINGS...WITH LITTLE IN THE WAY OF MAJOR
IMPACT EXPECTED WITH ANY OF THE WAVES THROUGH MONDAY MORNING.

OTHERWISE...DRY WEATHER WILL CONTINUE THROUGH EARLY NEXT WEEK AS
WE REMAIN UNDER THE INFLUENCE OF NORTHWEST TO WEST FLOW ALOFT.
VALLEYS WILL REMAIN STRONGLY INVERTED AS WE AWAIT A STRONGER
VALLEY SCOURING SYSTEM...WHICH LOOKS TO BE ARRIVING JUST OUTSIDE
OF THIS FORECAST WINDOW. THAT SYSTEM ARRIVES LATE THURSDAY AND
FRIDAY AND PROMISES TO BRING ANOTHER ROUND OF SNOW ALONG WITH A
REINFORCING SHOT OF COLD AIR. ECMWF AND THE GFS TO SOME
EXTENT...SHOW A SECOND PUSH SLIDING IN BY LATE IN THE WEEKEND.

TEMPERATURES WILL BE UNDERCUT ACROSS THE VALLEYS AS MOS GUIDANCE
CONTINUES TO STRUGGLE WITH THE COLD AIR MASS IN PLACE. AREAS ABOVE
THE STRONG VALLEY INVERSIONS WILL CONTINUE TO MODERATE WITH
READINGS CLIMBING ABOVE FREEZING FOR SEVERAL OF OUR HIGHER
VALLEYS BY EARLY NEXT WEEK.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 954 AM MST THU DEC 12 2013

VFR CONDITIONS WILL BE PREVAILING AT THE FORECAST TERMINALS
THROUGH THE AFTERNOON THOUGH TEMPORARY MVFR CONDITIONS DUE TO HAZE
UNDER THE INVERSION MAY AFFECT KVEL. AS TEMPERATURES COOL AFTER
SUNSET MVFR FOG WILL MOST LIKELY AGAIN AFFECT THE KVEL TERMINAL
DUE TO LIGHT FOG CONDITIONS. CONFIDENCE STILL LOW ON WIDESPREAD
FOG OR STRATUS IN THE VALLEYS AND WILL RETAIN THE PERSISTENCE
FORECAST.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...NONE.

UT...NONE.

&&

$$

SHORT TERM...JOE
LONG TERM...JDC
AVIATION...TGJT