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000
FXUS65 KBOU 032303
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
403 PM MST TUE DEC 3 2013

.SHORT TERM...STRONG WESTERLY FLOW ALOFT ACROSS COLORADO WITH UPPER JET BEGINNING
TO MOVE INTO COLORADO FROM THE NORTH. SNOW BECOMING WIDESPREAD
ACROSS THE MOUNTAINS...PARTICULARLY ALONG THE WEST FACING SLOPES OF
THE CONTINENTAL DIVIDE...WITH MODERATE SNOW ACROSS PORTIONS OF
SUMMIT COUNTY ALONG INTERSTATE 70. SNOW FINALLY SPREADING ONTO
THE FOOTHILLS. ACROSS PLAINS...COLD FRONT HAD PUSHED INTO PALMER
DIVIDE AND LINCOLN COUNTY...WITH TEMPERATURES FALLING BEHIND THE
FRONT. CURRENTLY IN THE LOWER TEENS ACROSS NORTHEAST LARIMER AND
NORTHWEST WELD COUNTIES. NORTHEAST WINDS PROVIDING A BIT OF
UPSLOPE IN AND NEAR FOOTHILLS. LOW LEVEL MOISTURE IS ACROSS MOST
OF THE PLAINS WITH RADAR SHOWING ECHOES FROM ACROSS EASTERN
LARIMER AND NORTHWEST WELD COUNTIES. THE SNOW WILL CONTINUE ACROSS
THE MOUNTAINS TONIGHT AS JET CONTINUES TO SAG SOUTH ACROSS
COLORADO WITH OROGRAPHICS AND DYNAMICS INCREASE. THE SNOW WILL
ALSO BECOME WIDESPREAD ALONG THE FOOTHILLS. SNOW COULD BE HEAVY AT
TIME...ESPECIALLY WEST FACING SLOPES. WILL CONTINUE WITH THE
WARNINGS FOR ALL OF THE MOUNTAINS...FOOTHILLS AND MOUNTAIN VALLEYS.
WITH JET NEARBY...CSI BANDED SNOW FALL IS CERTAINLY POSSIBLE.
ACROSS PLAINS SNOW WILL BE SHIFTING SOUTH AND EAST THROUGH THE
EVENING AND SHOULD BECOME WIDESPREAD ALONG THE URBAN CORRIDOR AND
ADJACENT PLAINS. CURRENT WARNINGS AND ADVISORIES STILL LOOK ON
REASONABLE BASED WITH DYNAMICS AND UPSLOPE. DECIDED TO CONTINUE
WITH WARNING FOR ZONE 41...THOUGH AMOUNTS MAY NOT REACH CRITERIA.
BUT WITH CSI POTENTIAL...THIS IS CERTAINLY POSSIBLE. SNOW AMOUNTS
TO BE LESS FURTHER EAST AWAY FROM THE TERRAIN INFLUENCE. THERE IS
SOME POTENTIAL FOR BLOWING SNOW BUT WILL HOLD OFF FOR NOW.
TEMPERATURES TO FALL INTO THE SINGLE DIGITS ACROSS THE PLAINS. ON
WEDNESDAY... SNOW WILL GRADUALLY TAPER OFF FROM NORTH TO SOUTH
DURING THE MORNING AS THE JET DYNAMICS SHIFTS SOUTH WITH PERHAPS
SOME IMPROVEMENT DURING THE AFTERNOON. STILL SOME CSI POTENTIAL TO
WARRANT KEEPING THE HILITES GOING THROUGH THE DAY. CERTAINLY
ISSUES FOR THE MORNING COMMUTE. MODELS SHOW ANOTHER SURGE OF
COLDER AIR SPREADING ACROSS THE PLAINS...HIGHS MAY ONLY BE IN THE
TEENS.

.LONG TERM...MODELS KEEP A SIGNIFICANT WEST-SOUTHWESTERLY JET
MAXIMUM OVER THE CWA WEDNESDAY NIGHT INTO THURSDAY MORNING. SPEEDS
ARE UP TO 150 KNOTS OVER US. THE WEST-SOUTHWESTERLY FLOW ALOFT
CONTINUES THURSDAY AND THURSDAY NIGHT...BUT IT DECREASES A BIT ON
FRIDAY. THE UPPER TROUGH AXIS IS OVER WESTERN COLORADO BY 12Z
FRIDAY MORNING. ON FRIDAY...FAIRLY STRONG WESTERLY FLOW ALOFT IS
PROGGED FOR US. DOWNWARD SYNOPTIC SCALE ENERGY IS PROGGED THURSDAY
NIGHT...THEN UPWARD ENERGY THURSDAY AND THURSDAY EVENING. THE
BOUNDARY LAYER FLOW IS PROGGED TO BE NORTHERLY THURSDAY
EVENING...THEN WEAK OVERNIGHT INTO THURSDAY MORNING. EASTERLIES
ARE PROGGED THURSDAY AFTERNOON THROUGH FRIDAY NIGHT. FOR
MOISTURE...WEDNESDAY NIGHT DRIES OUT ON ALL THE MODELS...WITH THE
NAM THE DRIEST AND THE GFS THE WETTEST. MODELS INCREASE MOISTURE
BY THURSDAY AFTERNOON WELL INTO THURSDAY NIGHT. IT DRIES OUT A
LITTLE BIT FRIDAY...BUT NOT SIGNIFICANTLY. THE QPF FIELDS HAD TINY
AMOUNTS OF MEASURABLE SNOWFALL FOR THE CWA THURSDAY EVENING...THEN
NEAR NOTHING OVERNIGHT AND THURSDAY MORNING. WIDER COVERAGE OF A
SMALL AMOUNT RETURNS TO NEARLY ALL THE CWA THURSDAY AFTERNOON AND
NIGHT INTO EARLY FRIDAY. THERE IS LITTLE ON FRIDAY. SO AFTER
EARLY WEDNESDAY EVENING`S "LIKELY" POPS IN THE MOUNTAINS...WILL GO
"CHANCE"S THERE THROUGH THURSDAY EVENING...THEN "SLIGHT CHANCE"S
TO NOTHING ON FRIDAY. FOR THE PLAINS 10-20%S WILL BE GOOD FOR MOST
AREAS. THE EXCEPTION IS THE PALMER RIDGE AND LINCOLN COUNTY. WILL
GO "CHANCE"S THERE WEDNESDAY NIGHT AND THURSDAY AFTERNOON.
SNOWFALL AMOUNTS WILL BE MINIMAL WEDNESDAY NIGHT THROUGH FRIDAY.
TEMPERATURES LOOK TO BE ABOUT 30 DEGREES BELOW NORMAL ON THE LOWS
AND HIGHS. THURSDAY`S HIGHS WILL BE SIMILAR TO WEDNESDAY`S. FRIDAY
MAY WARM UP 2-3 C FROM THURSDAY. FOR THE LATER DAYS...SATURDAY
THROUGH TUESDAY...UPPER LEVEL TROUGHINESS IS PROGGED TO CONTINUE
OVER THE CWA THROUGH MONDAY...WITH STRONG NORTHWESTERLY FLOW ALOFT
TUESDAY. MODELS SHOW A DECENT BATCH OF ENERGY TO MOVE ACROSS
SATURDAY INTO SUNDAY...SO WILL KEEP THE POPS GOING...HIGHEST IN
THE MOUNTAINS. TEMPERATURES STAY PRETTY COLD THROUGH MONDAY...WITH
A TAD OF A WARM-UP TUESDAY. THE SATURDAY/SUNDAY ENERGY COULD
BRING MEASURABLE SNOW TO ALL THE CWA.

&&

.AVIATION...ARCTIC FRONT HAS COME AND GONE WITH GUSTY NORTHERLY
WINDS IN ITS WAKE. STRATUS HAD DEVELOPED A BIT QUICKER THAT
ORIGINALLY THOUGHT. SOME LIGHT SNOW WILL BE POSSIBLE BY THE
EVENING...BUT WILL BECOME WIDESPREAD DURING THE EVENING AND
CONTINUE THROUGH WEDNESDAY MORNING WITH IFR CONDITIONS PREVAILING
DUE TO THE SNOW. SOME POTENTIAL FOR BANDS OF MODERATE TO HEAVY
SNOW WITH SNOWFALL RATES OF AROUND AN INCH PER HOR. WINDS WILL
REMAIN NORTHEAST WITH SPEEDS 10 TO 20 MPH. SOME IMPROVEMENT BY 18Z
WEDNESDAY...THOUGH LIGHT SNOW WILL CONTINUE THROUGH THE AFTERNOON.
TOTAL SNOWFALL FOR KDEN LOOKS TO BE IN THE 3 TO 6 INCH RANGE WITH
5 TO 9 INCHES POSSIBLE AT KAPA AND KBJC.


&&

.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>034.

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

&&

$$

SHORT TERM...D-L
LONG TERM....RJK
AVIATION...D-L