FXUS65 KBOU 292142
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER CO
241 PM MST SUN NOV 29 2009

.SHORT TERM...NEARLY ZERO CLOUDS OVER THE FORECAST AREA AT THIS 
TIME.  A TINY BIT OVER SOUTHERN LINCOLN COUNTY IS ABOUT ALL I CAN 
SEE.  THERE ARE VERY LIGHT WINDS OVER THE WESTERN TWO-THIRDS OF THE 
FORECAST AREA CURRENTLY...THE EASTERN THIRD HAS NORTHWESTERLY 
SURFACE WINDS AT SPEEDS UNDER 15 MPH.  MODELS KEEP THE FORECAST AREA 
UNDER AN UPPER RIDGE POKING IN FROM THE DUE WEST OF COLORADO.  THE 
FLOW ALOFT IS PROGGED TO BE MODERATE IN SPEED AND FROM THE 
NORTH-NORTHEAST.  THE QG VERTICAL VELOCITY FIELDS SHOW THE FORECAST 
AREA IN WEAK DOWNWARD MOTION TONIGHT AND MONDAY.  THE LOW LEVEL 
PRESSURE AND WIND FIELDS HAVE A WEAK GRADIENT IN PLACE TONIGHT AND 
MONDAY WITH WEAK NORMAL DIURNAL WIND PATTERNS EXPECTED.  THERE IS 
LITTLE OF NO MOISTURE ON EITHER MODEL.  THE IS NO MEASURABLE 
PRECIPITATION ON THE QPF FIELDS.  THERE WILL BE NO POPS.  FOR 
TEMPERATURES...MONDAY HIGHS ARE PROGGED TO BE 4 TO 7 C WARMER THAN 
TODAY'S. 

.LONG TERM...ONLY MINOR VARIATIONS NOW IN THE MODELS OVER OUR AREA 
THROUGH WEDNESDAY...MAINLY THE STRENGTH OF THE TROUGH PASSING TO OUR 
NORTHEAST. THIS WILL CHIEFLY AFFECT THE CLOUD COVER AND THREAT OF 
LIGHT SNOW TUESDAY NIGHT AND EARLY WEDNESDAY. FRONT STILL ON 
SCHEDULE FOR TUESDAY AFTERNOON WITH MIDDAY HIGHS LIKELY. PRETTY DRY 
ENVIRONMENT OVERALL...BUT THERE WILL LIKELY BE A MID LEVEL CLOUD 
BAND THAT COULD HAVE SOME LIGHT SNOW IN IT. MODELS TRAP A LITTLE 
MOISTURE IN THE EDDY ON THE EAST SIDE OF THE FRONT RANGE DURING THE 
DAY WEDNESDAY WHILE THERE IS CLEARING EVERYWHERE ELSE...NOT SURE IT 
THAT WILL PAN OUT AND IT MAY CLEAR MORE QUICKLY THAN THAT AS IT DID 
TODAY. COOLER AIR WILL REMAIN IN PLACE...JUST NOT SATURATED.

THERE STILL REMAINS MUCH DIVERSITY IN THE MODEL SOLUTIONS IN THE 
LAST HALF OF THE PERIOD AS THERE IS MUCH DIFFICULTY RESOLVING 
UPSTREAM DEVELOPMENTS. LATEST TREND THAT SEEMS TO HAVE SOME 
AGREEMENT IS RIDGING CENTERED OVER SOUTHEAST ALASKA FORCED BY STRONG 
STORM DEVELOPMENT IN THE NORTH PACIFIC. THIS WILL LIKELY FORCE 
TROUGHING INTO THE NORTHWESTERN U.S. BUT HOW STRONG...WHAT 
TRAJECTORY THE COLD AIR TAKES HEADING SOUTH...AND WHAT INTERACTION 
THERE IS WITH ANY FLOW UNDERCUTTING THE RIDGE IS ALL STILL IN 
QUESTION. THE MODELS SHOWED AN UPSTREAM TROUGH GIVING US A GOOD 
STORM ON FRIDAY TWO DAYS AGO...ON SATURDAY YESTERDAY...AND NOW ON 
SUNDAY...SO WE ARE NOT CATCHING UP HERE. WITH SOME DECREASE IN THE 
DISAGREEMENT ON THE GENERAL PATTERN I WENT AHEAD AND REDUCED POPS 
AND RAISED TEMPS A BIT IN THE THURSDAY/FRIDAY PERIOD AND WENT COLDER 
WITH A BIT HIGHER POPS ON SUNDAY...BUT THIS COULD EASILY TURN OUT TO 
BE THE WRONG DAY AS A DEEPER TROUGH WOULD LIKELY BE SLOWER. 
COMPLICATING MATTERS IS THAT THE SOLUTION WE SEEM TO BE HEADING FOR 
MAY HAVE A BETTER CHANCE OF GIVING US A WARMUP IN WESTERLY FLOW 
AHEAD OF THE NEXT TROUGH...SO IT COULD TURN OUT TO BE A FAIRLY MILD 
WEEKEND IF THE TROUGH IS SLOWER. 

&&

.AVIATION...THERE WILL NO CLOUDS TO A FEW HIGH CLOUDS FOR DIA 
TONIGHT AND MONDAY.  WINDS WILL ADHERE TO THE NORMAL DIURNAL 
PATTERNS...AND WEAKER THAN NORMAL SPEEDS.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...NONE. 

$$
RJK/GIMMESTAD