000
FXUS65 KBOU 181020
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER CO
320 AM MST TUE NOV 18 2008

.SHORT TERM...BROAD UPPER LEVEL RIDGE OF HIGH PRESSURE CONTINUES TO 
PUSH EASTWARD TOWARDS COLORADO WITH CONTINUED RISING HEIGHTS AND 
WARMING TEMPS. 700MB TEMPS WILL BE AROUND +9C BY 00Z WED AND EXPECT 
ANOTHER 5-10 DEGREES OF WARMING TODAY ALONG WITH A WEAK WESTERLY 
DOWNSLOPE COMPONENT. FCST SOUNDINGS SUPPORT TEMPS AROUND 80 DEGREES 
OVER THE URBAN CORRIDOR AND JUST BIT COOLER OVER THE FAR NERN PLAINS 
WITH A WEAK LOW LVL INVERSION REMAINING.  THE RECORD HIGH FOR DENVER 
TODAY IS 74 TODAY AND THIS SHOULD BE EASILY SMASHED. THE RECORD HIGH 
FOR ALL OF NOVEMBER IS 80 DEGREES...SO WE WILL BE VERY CLOSE TO THIS 
RECORD AS WELL. THERE IS SOME WAVE CLOUDS UP OVER NRN WYOMING BUT 
FEEL THE THICKER CLOUD WILL STAY NORTH OF COLORADO AND WON'T EFFECT 
OUR SFC WARMING TODAY. 

GIVEN THE VERY WARM TEMPS AND CONTINUED DROPPING DEWPOINTS...RH LVLS 
WILL BE UNDER 10% OVER THE FRONT RANGE. GAVE SOME THOUGHT TO 
INCREASED FIRE DANGER TODAY...BUT DON'T THINK WE'LL GET STRONG 
ENOUGH WINDS FOR WIDESPREAD RED FLAG CONDITIONS. NAM CROSS SECTIONS 
SHOW WE MAY GET A FEW GUSTS TO 25 MPH IN THE FOOTHILLS/ADJ PLAINS 
BUT FEEL THESE WILL BE FAIRLY LOCALIZED AS WINDS ALOFT CONTINUE TO 
DECREASE. 

SATELLITE PICS SHOWING A BIT OF STRATUS DEVELOPING OVER THE NEBRASKA 
PANHANDLE ATTM...AND WITH LOW T/TD SPREADS WILL ADD SOME 
CLOUDS/PATCHY FOG OVER ZONES 50/51 FOR EARLY THIS MORNING. 

.LONG TERM...UPPER LEVEL RIDGE WILL STILL PROVIDE ONE MORE MILD AND 
DRY DAY WEDNESDAY...BUT LOW LEVEL COOLING WILL COMMENCE WITH 
TEMPERATURES AT LEAST 10-15F COOLER ACROSS THE PLAINS.  THEN SECOND 
AND MUCH COLDER SURGE OF LOW LEVEL AIR IS STILL ON TRACK TO PUSH 
ACROSS THE PLAINS WEDNESDAY EVENING.  LOW LEVELS ARE FORECAST TO 
BECOME NEARLY SATURATED SO EXPECT WIDESPREAD STRATUS AND AREAS OF 
FREEZING DRIZZLE AND FOG TO DEVELOP.  FORECAST SOUNDINGS SHOW 
TEMPERATURES IN THE MOIST LAYER ONLY AS COLD AS -5 TO -10C...SO MAIN 
PRECIP THREAT SHOULD REMAIN DRIZZLE RATHER THAN ANY SNOW.  SURFACE 
TEMPERATURES BY THURSDAY MORNING SHOULD BE COLD ENOUGH TO ALLOW 
FREEZING DRIZZLE AS UPSTREAM OBS BEHIND THIS COLD FRONT ARE NOW IN 
THE UPPER SINGLE DIGITS AND TEENS IN NORTHERN BRITISH COLUMBIA.  
THURSDAYS HIGH TEMPERATURES IN THE 30S LOOK RATHER BLEAK COMPARED TO 
TODAY...AND WE MAY EVEN STRUGGLE TO MOVE MORE THAN A COUPLE DEGREES 
FROM THE MORNING LOWS GIVEN VERY STRONG LOW LEVEL INVERSION AND 
CLOUDS.

NEXT QUESTIONS SURROUND WHAT APPEARS TO BE A WEAK WAVE MOVING 
THROUGH THE MEAN UPPER LEVEL RIDGE OVER THE WESTERN U.S. ON FRIDAY.
THE GFS AND NAM SEEM TO BE QUITE A BIT STRONGER WITH THIS...STRONG 
ENOUGH TO PRODUCE SOME SHOWERS AT LEAST IN THE MOUNTAINS.  HOWEVER...
ECMWF WAS MUCH WEAKER WITH THIS FEATURE AND STILL SEEMS PREFERRED AT 
THIS TIME...SO WILL KEEP THE FORECAST DRY FOR NOW.  THERE IS ANOTHER 
WAVE NOTED FOR SUNDAY...BUT MAIN AFFECTS SHOULD REMAIN NORTH OF OUR 
FORECAST AREA.

MODEL SOLUTIONS REALLY BECOME DISORGANIZED FOR THE FIRST HALF OF 
NEXT WEEK...SO NO CHANGES TO MAINLY DRY AND MILD WEATHER ALREADY IN 
THE FORECAST.

&&

.AVIATION...VFR CONDITIONS WILL CONTINUE THROUGH TUESDAY WITH SOME 
MIDDLE AND HIGH LEVEL CLOUDS. TYPICAL SFC DIURNAL WIND PATTERNS THRU 
EARLY AM...SHIFTING TO THE WEST BY 18Z. SPEEDS SHOULD STAY BELOW 15 
KTS....BUT EXPECT A FEW GUSTS 20-30KT IN/NEAR THE FOOTHILLS LIKE 
BJC.  

IFR CONDITIONS ARE EXPECTED TO DEVELOP AFTER MIDNIGHT WEDNESDAY 
NIGHT AND CONTINUE THROUGH MUCH OF THURSDAY.  SOME LIGHT FREEZING 
DRIZZLE AND FOG IS ALSO POSSIBLE AT THAT TIME.

&&

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

$$

SWE/BARJENBRUCH