FXUS65 KBOU 282132
AFDBOU
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER CO
235 PM MST SAT NOV 28 2009
.SHORT TERM...WEAK SFC COLD FRONT MOVED THROUGH LATE THIS MORNING
WITH SOME SHALLOW UPSLOPE UP TO 700MB ACROSS THE FRONT RANGE ATTM.
MOISTURE STILL IN THE MID AND UPPER LVL VARIETY AND STILL LOW LVL
MOISTURE IS STILL LACKING...EVEN ACROSS SRN WYOMING. WEAK UPSLOPE
EXPECTED TO REMAIN IN PLACE TONIGHT AND GRADUALLY LOW LVL MSTR
EXPECTED TO INCREASE THIS EVENING OVER THE FRONT RANGE. SPLIT FLOW
PATTERN IN PLACE WITH THE BRUNT OF THE ENERGY WITH THIS SYSTEM
DIVING INTO THE DESERT SOUTHWEST. NORTHERN BRANCH WILL SEND A WEAK
RIPPLE ACROSS NRN CO AND STILL SOME WEAK ASCENT NOTED IN VERTICAL
VELOCITY FIELDS THROUGH EARLY SUN AM. LATEST 18Z NAM A BIT WETTER
THAN 12 RUNS OVER THE FRONT RANGE BUT GIVEN LACK OF CURRENT PRECIP
ACROSS WYOMING WILL KEEP CHANCE POPS OVER THE URBAN CORRIDOR. WILL
NUDGE THE FOOTHILLS UP TO LIKELY FOR ACCUMULATION UP TO AN INCH.
OVER THE URBAN LOCATIONS...JUST SOME FLURRIES OR A DUSTING OF SNOW.
THE MOISTURE AND ANY PRECIP WILL BE SAGGING RAPIDLY SOUTHWARD SUNDAY
MORNING AND WILL GO WITH A QUICKER ENDING OF LINGERING FLURRIES WITH
MOST LOCALES BECOMING MOSTLY SUNNY BY AFTERNOON. FURTHER COOLING ON
SUNDAY WITH READINGS REMAINING IN THE LOWER 40S.
.LONG TERM...MODELS HAVE COME INTO BETTER AGREEMENT THROUGH
WEDNESDAY...STILL A MESS BEYOND THAT. STILL LOOKING AT A GOOD BREAK
BETWEEN SYSTEMS WITH NEARLY CLEAR SKIES AND A DRY AIRMASS...NUDGED
TEMPS UP MONDAY AND DOWN A LITTLE MONDAY NIGHT. FRONT EXPECTED
TUESDAY AFTERNOON WITH MOST OF THE LIFT NORTHEAST OF US. MODELS HAVE
A LITTLE LIGHT SNOW RIPPLING ALONG THE FRONT...BUT OVERALL A PRETTY
DRY ENVIRONMENT. SHALLOW COLD AIR SHOULD REMAIN OVER THE EAST...
WHILE ANYONES GUESS WHAT WILL BE HAPPENING ALOFT IN THE THURSDAY
THROUGH SATURDAY TIMEFRAME. EACH MODEL RUN REMAINS DIFFERENT WITH
SHORTWAVES FROM THE NORTH OR WEST...OR A LOW TRYING TO UNDERCUT AN
UPSTREAM RIDGE. LATEST TRENDS ARE MORE TOWARD THE INITIAL COLD POOL
SHIFTING EAST AND SOME KIND OF TROUGH DEVELOPING AGAIN
UPSTREAM...KEEPING THE COLDEST AIR AWAY BUT POTENTIALLY GIVING US A
BETTER CHANCE OF SNOW OVER THE WEEKEND. MAIN QUESTION FOR NOW IS
POTENTIAL FOR A WARMUP AND/OR WINDY PERIOD IN THE MOUNTAINS BETWEEN
THE TWO TROUGHS. EAST SHOULD REMAIN IN THE COLD AIR...THOUGH IT IS
NOT REALLY COLD AND THERE COULD BE SOME WARMING ALONG THE FOOTHILLS
IF IT GETS BREEZY.
&&
.AVIATION...SURFACE WINDS TO REMAIN OUT OF THE N-NE THROUGH MUCH OF
THRU LATE TNT THEN BECOMING LIGHT/VRB. LOW LVL FLOW TO MOISTEN UP
WITH MVFR CIGS DEVELOPING BY EVENING. THE POSSIBILITY OF -SN STILL
EXISTS WITH BEST CHANCES BETWEEN 05Z-12Z TNT. HIGHER PROBABILITIES
OF NO SNOW ACCUM AND JUST FLURRIES. LOWER CHANCES OF ACCUM UP TO 1/2
INCH...ESP AT BJC/APA.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...NONE.
$$
ENTREKIN/GIMMESTAD