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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS65 KBOU 011746
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
1046 AM MST SUN FEB 1 2015

.UPDATE...
ISSUED AT 1010 AM MST SUN FEB 1 2015

THERE IS STILL A BATCH AND BANDS OF REAL LIGHT SNOW FROM AROUND
EAST CENTRAL LARIMER COUNTY SOUTHEASTWARD INTO ELBERT NORTHERN
LINCOLN AND SOUTHWESTERN WASHINGTON COUNTIES. AGAIN IT IS VERY
LIGHT AND ADDITIONAL ACCUMULATIONS WILL BE UNDER ONE INCH
EVERYWHERE IT IS SNOWING. ALL THE PLAINS AND LOWER FOOTHILLS HAVE
UPSLOPE FLOW AT THIS TIME. PLAINS TEMPERATURES ARE IN THE TEENS TO
LOWER 20S. WILL ADJUST TEMPERATURES AND WEATHER ACCORDINGLY.

UPDATE ISSUED AT 700 AM MST SUN FEB 1 2015

SNOW HAS DECREASED IN ALMOST ALL OF THE WINTER WEATHER ADVISORY
AREA SO HAVE CANCELLED IT.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 415 AM MST SUN FEB 1 2015

WOW. ALL INGREDIENTS CAME TOGETHER FOR A HEAVY SNOW EVENT LAST
NIGHT IN THE DENVER METRO AREA. THOSE WOULD BE CONVECTION...JET
MAX...UPSLOPE COMPONENT BEHIND FRONT TO FOCUS CONVECTION...
UNSEASONABLY HIGH PRECIPITABLE WATER...AND DENDRITIC CRYSTAL
GROWTH. THE JET MAX ENDED UP TO OUR WEST VERSUS OVER OR JUST EAST
OF US THUS PROLONGING THE EVENT AS WELL. MEANWHILE FORT COLLINS
AND LOVELAND SAW LITTLE IF ANY SNOW.

THERE ARE STILL A FEW HEAVIER SNOW BANDS AROUND THIS MORNING IN
THE DENVER AREA TO PALMER DIVIDE...AND GIVEN HIGH IMPACT OF LAST
 WET SNOW ON ROADS WILL EXTEND THE WINTER WEATHER ADVISORY A FEW
HOURS TIL 9 AM. ADDITIONAL ACCUMULATIONS SHOULD BE AN INCH OR LESS
AFTER 12Z IN DENVER WHILE THE PALMER COULD STILL PICK UP 1-2
INCHES IN A FEW BANDS. HOWEVER...JET AXIS IS SHIFTING SLOWLY EAST
SO THIS SHOULD HELP ALLEVIATE WIDESPREAD HEAVIER SNOW.

THERE ARE ALREADY SOME BREAKS IN THE CLOUDS ON THE REST OF THE
PLAINS AND HIGH MOUNTAIN VALLEYS...AND THESE WILL BECOME MORE
NUMEROUS THROUGH THE DAY. CANT RULE OUT SHALLOW CONVECTIVE SHOWERS
WITH DAYTIME HEATING PER LATEST FORECAST SOUNDINGS...BUT ONLY
ISOLATED AT MOST AS AIRMASS CONTINUES TO DRY.

FOR TONIGHT...WESTERLY FLOW INCREASES SIGNIFICANTLY AFTER MIDNIGHT
WITH A RETURN OF WARM ADVECTION MOISTURE IN THE MOUNTAINS. THIS
WOULD BE ENOUGH TO BRING A COUPLE INCHES OF SNOW TO THE MOUNTAINS
MAINLY AFTER MIDNIGHT...WITH MORE INTO MONDAY. STRONG WINDS ABOVE
TIMBERLINE AND SOME MOUNTAIN WAVE ENHANCEMENT POSSIBLE IN THE
FOOTHILLS AS WELL...SO WILL CONTINUE STRONG AND GUSTY WINDS UP
THERE BUT NOT ORGANIZED ENOUGH AT THIS TIME FOR HIGH WINDS.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 415 AM MST SUN FEB 1 2015

NORTHWESTERLY FLOW ALOFT IS GOING TO DOMINATE THE WEATHER PICTURE
THIS WEEK. EARLY IN THE WEEK WILL BE MOIST NORTHWEST FLOW AS A
WEAK UPPER RIDGE STRUGGLES TO BUILD OVER THE WEST COAST. THIS WILL
KEEP SNOWFALL GOING IN THE MOUNTAINS BUT LEAVE THE PLAINS DRY.
GUSTY WINDS WILL BE POSSIBLE MONDAY NIGHT AND TUESDAY AS A JET
STREAM MAX MOVES OVER WYOMING AND THE NORTHERN TIER OF COLORADO.
MOUNTAINS AND FOOTHILL AREAS WOULD BE THE WINDIEST. WILL BE
KEEPING AN EYE ON HOW THIS JET STREAM DEVELOPS BEFORE ISSUING ANY
WIND HIGHLIGHTS. SNOWFALL AMOUNTS IN THE MOUNTAINS ARE EXPECTED TO
REMAIN LIGHT...BUT AS THE LIGHT SNOW PERSISTS FOR SOME 48
HOURS...APPRECIABLE AMOUNTS WILL BE POSSIBLE. TEMPERATURES ON
THE PLAINS MONDAY AND TUESDAY WILL BE MUCH WARMER THAN SEASONAL
NORMALS...DUE TO DOWNSLOPE WARMING.

ON WEDNESDAY...THINGS CHANGE FOR THE PLAINS AS A COLD FRONT DROPS
DOWN FROM THE NORTHERN PLAINS. UPSLOPE FLOW BEHIND THE FRONT WILL
BRING A CHANCE OF SNOW TO THE PLAINS ALONG WITH AFTERNOON HIGHS
ONLY IN THE 30S. MOUNTAIN AREAS WILL CONTINUE WITH MORE LIGHT
SNOWFALL.

DURING THE LATTER HALF OF THE WEEK...THE UPPER RIDGE OVER THE WEST
COAST FINALLY STRENGTHENS AS IT BUILDS OVER THE GREAT BASIN. AS
THE RIDGE AMPLIFIES...THE FLOW OF MOISTURE WILL BE CUT
OFF...MAKING THURSDAY AND FRIDAY DRY ACROSS THE FORECAST AREA.
TEMPERATURES WILL ALSO WARM BACK TO EARLY SPRINGLIKE VALUES
AROUND THE 60 DEGREE MARK ON THE PLAINS. MOUNTAIN TEMPERATURES
SHOULD MAKE IT TO THE 30S AND LOWER 40S.

VARIOUS MODELS SHOW AGREEMENT WITH EVOLUTION OF THE WESTERN U.S.
UPPER RIDGE THROUGH THE WEEK...LENDING CONFIDENCE TO THE FORECAST
SCENARIO BEING CONVEYED.

&&

.AVIATION...(FOR THE TAFS THROUGH 18Z MONDAY MORNING)
ISSUED AT 1010 AM MST SUN FEB 1 2015

CEILINGS WILL CONTINUE FAIRLY LOW AT DIA INTO THE MID AFTERNOON.
THEY MAY GET ABOVE BKN070 BEFORE 00Z. REAL LIGHT SNOW IS STILL A
POSSIBILITY THROUGH ABOUT 21Z. THE WINDS WILL KEEP AN UPSLOPE
COMPONENT TO THEM UNTIL AROUND 03Z...THEN DRAINAGE PATTERNS ARE
LIKELY.

&&

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

$$

UPDATE...RJK
SHORT TERM...BARJENBRUCH
LONG TERM...DANKERS
AVIATION...RJK