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000
FXUS65 KBOU 031039
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
339 AM MST TUE DEC 3 2013

.SHORT TERM...INITIALLY...STILL DEALING WITH SOME STRONG AND
GUSTY WINDS OVER THE FOOTHILLS AND ADJACENT PLAINS. SOME ENHANCED
SUBSIDENCE HAS MOVED OVER THE AREA DURING THE PAST FEW HOURS AND
LED TO THE INCREASED WINDS. STILL SEEING SOME GUSTS IN THE 50-70
MPH RANGE AND AGAIN GETTING VERY CLOSE TO HIGH WIND CRITERIA AGAIN.
THE WINDS SHOULD BE SHORT LIVED AND MORE LOCALIZED AS SUBSIDENCE
MOVES AWAY WITH LARGE SCALE ASCENT COMING INTO COLORADO THIS
MORNING. WIND SIGNATURE ON RADAR HAS ALSO BEGUN TO DISSIPATE AS
WELL.

THE ARCTIC COLD FRONT STILL ON TRACK BUT THERE HAS BEEN SOME
SLIGHT SLOWING IN THE TIMING FROM PREVIOUS FORECAST. CURRENTLY
THE FRONT IS JUST MOVED THROUGH CASPER WYOMING AND SHOULD MOVE
THROUGH NORTHEAST COLORADO LATE AM THROUGH THE AFTERNOON. HAVE
INCREASED TEMPERATURES A BIT DUE TO THE SLOWER TIMING OF FRONT
ESPECIALLY OVER SOUTHERN PORTIONS OF CWA. SNOW WILL DEVELOP LATE
AFTERNOON AND EVENING AND STILL LOOKS TO BECOME WIDESPREAD FROM
LATE EVENING THROUGH OVERNIGHT OVER FRONT RANGE AND ADJACENT
PLAINS. GIVEN THE SHALLOW UPSLOPE AND STRONG JET OVERHEAD WILL
UPGRADE THE WATCH TO A WARNING FOR THE FOOTHILLS AND ADJACENT
PLAINS. ONLY CHANGE WAS TO DELAY THE TIMING FROM 22Z TO 01Z WITH
THE SLOWER ARRIVAL. OPTED FOR A ADVISORY FOR ZONES 40..43 AS
AMOUNTS A BIT LIGHTER AS YOU MOVE AWAY FROM THE ENHANCED UPSLOPE
TERRAIN. SNOW ACCUMULATION WILL BE LESS AS YOU MOVE FURTHER AWAY
FROM THE MOUNTAINS BUT STILL AN INCH OR TWO POSSIBLE OVER THE FAR
NORTHEAST PLAINS.

AS FOR THE MOUNTAINS...SNOW A BIT DELAYED AS WELL BUT WILL KEEP
WITH CURRENT TIMING. SNOW SHOULD BECOME MORE WIDESPREAD BY LATER
THIS MORNING AS MOISTURE AND JET MOVE INTO NORTHERN COLORADO.
LITTLE CHANGE IN THE TEMPERATURE FORECAST WITH BIG DROP IN TEMPS
INTO THE TEENS AND SINGLE DIGITS TONIGHT OVER THE ENTIRE AREA.

.LONG TERM...SNOW WILL CONTINUE WEDNESDAY AS WELL AS AN EXTRA
SURGE OF COLD AIR CREATING TEMPERATURES THAT WILL BARELY WARM
DURING THE DAY AND WILL APPROACH RECORDS FOR A LOW MAX. SNOW WILL
AGAIN BE FALLING ACROSS MOST OF THE AREA WITH HEAVIER AMOUNTS OVER
THE MOUNTAINS AND OVER THE URBAN CORRIDOR INTO THE FOOTHILLS WITH
UPSLOPE FLOW. BANDING MAY STILL OCCUR DURING THE DAY AS THE JET
PASSES SLOWLY OVERHEAD TO THE SOUTH. DURING THE EVENING...THE
700MB FLOW BECOMES WESTERLY AS THE LOW OPENS UP AND MOVES EAST.
THIS WILL BE DIMINISHING THE SNOW DURING THIS TIME...SO THE END
TIME OF THE HIGHLIGHTS LOOK GOOD WITH ONLY UP TO ANOTHER INCH
EXPECTED OVERNIGHT.

A WEAK DISTURBANCE IN THE LONGWAVE TROUGH WILL MOVE OVERHEAD
THURSDAY PUSHING IN MORE COLD AIR AND LIGHT SNOW. MOUNTAIN AREAS
WILL ONLY SEE A FEW INCHES OR LESS WITH THE PLAINS SEEING LESS
THAN AN INCH. HIGHS WILL LIKELY STAY IN THE SINGLE DIGITS OVER THE
PLAINS WITH A FEW NEGATIVE VALUES IN THE HIGH MOUNTAINS.
AGAIN...RECORDS FOR LOW MAX TEMPS WILL BE APPROACHED.

BRIEF RIDGING WILL OCCUR FRIDAY TO BRING A RESPITE FROM SNOW TO
THE PLAINS WITH A FEW DEGREES OF WARMING AS WELL. HOWEVER...THE
MOUNTAINS WILL LIKELY CONTINUE TO SEE LIGHT SNOW THROUGHOUT THE
DAY. YET ANOTHER DISTURBANCE IN THE NEARLY STATIONARY LONGWAVE
TROUGH WILL DIG FROM THE GREAT BASIN AND INTO THE STATE SATURDAY.
NOT AS MUCH MOISTURE IS EXPECTED WITH THIS SYSTEM...BUT EXPECT
SNOW FOR THE FORECAST AREA FOR SATURDAY AND POSSIBLY INTO SUNDAY
IF THE ECMWF IS CORRECT IN KEEPING THE TROUGH AROUND RATHER THAN
MOVING INTO OUT QUICKLY LIKE THE GFS. HAVE KEPT IN A SLIGHT CHANCE
FOR THE FORECAST AREA FOR SUNDAY FOR THIS. TEMPERATURES WILL
REMAIN BELOW FREEZING FOR THE WEEKEND AND INTO MONDAY WITH
READINGS LIKELY TO STAY BELOW 20 DEGREES.


&&

.AVIATION...SURFACE WINDS VERY SQUIRRELY THIS AM WITH MOUNTAIN
WAVE ON-GOING. GENERALLY LIGHT SOUTHEAST WINDS BUT WILL INDICATE
LLWS WITH STRONGER WEST WINDS JUST OFF THE DECK. COLD FRONT WILL
MOVE INTO LOCAL TERMINALS EARLY THIS AFTERNOON AS WINDS SHIFT
NORTH AND NORTHEAST AND INCREASE. CEILINGS WILL LOWER LATER THIS
AFTERNOON WITH SNOW DEVELOPING AND IFR CONDITIONS BY EVENING WITH
SNOW. SNOWFALL AT LOCAL TERMINALS BY 12Z WEDNESDAY LOOKS TO BE 2
TO 5 INCHES AT DEN WHILE 4 TO 8 INCHES POSSIBLE AT APA/BJC. BANDS
OF HEAVY SNOW POSSIBLE WITH SNOWFALL RATES UP TO AN INCH/HR.


&&

.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING FROM 6 PM THIS EVENING TO 6 PM MST
WEDNESDAY FOR COZ035>039-041.

WINTER STORM WARNING UNTIL 6 PM MST WEDNESDAY FOR COZ030-032>034.

WINTER STORM WARNING UNTIL 6 PM MST WEDNESDAY FOR COZ031.

WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 6 PM MST
WEDNESDAY FOR COZ040-043.

&&

$$

SHORT TERM...ENTREKIN
LONG TERM....KRIEDERMAN
AVIATION...ENTREKIN