Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 251651
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
951 AM MST SUN JAN 25 2015

.UPDATE...
ISSUED AT 951 AM MST SUN JAN 25 2015

VISIBLE SATELLITE SHOWS A MID LEVEL CLOUD BAND SHIFTING SLOWLY
EAST AND SOUTHEAST ACROSS THE PLAINS. MOST OF THIS CLOUD IS JUST
EAST OF THE I-25 URBAN CORRIDOR AS DOWNSLOPE COMPONENT OFF THE
FRONT RANGE ELIMINATING CLOUD DEVELOPMENT THERE. THIS CLOUD BAND
WILL ADVECT SLOWLY EASTWARD TODAY PER LATEST MODEL DATA AND
CONTINUATION OF DOWNSLOPE COMPONENT OFF THE FRONT RANGE. IN THE
MOUNTAINS AND HIGH VALLEYS...THE MID LEVEL CLOUD DECK IS TRAPPED
UNDER A WEAK INVERSION SO IT WILL ONLY BE SLOW TO ERODE THROUGH
THE AFTERNOON AND EVENING. A COUPLE OF CAMS OVER THE HIGHEST PEAKS
SHOWED A BIT OF ICING EARLIER THIS MORNING LIKELY DUE TO FREEZING
DRIZZLE. HOWEVER...MOISTURE DECK IS BECOMING MORE SHALLOW THROUGH
THE DAY AND GRADUALLY LIFTING SO DONT EXPECT MUCH MORE THAN A FEW
FLURRIES/SPOTTY FREEZING DRIZZLE OVER THE HIGHER PEAKS.

UPDATE ISSUED AT 644 AM MST SUN JAN 25 2015

UPDATED SKY GRIDS TO ACCOUNT FOR A SOONER THAN EXPECTED INCREASE
IN HIGH CLOUD COVERAGE THIS MORNING. CIRRUS SHIELD COULD BECOME
RATHER THICK OVER PARTS OF THE I-25 CORRIDOR LATE THIS
MORNING/EARLY THIS AFTERNOON WHEN THE MAIN BATCH OF HIGH-LEVEL
MOISTURE NOW OVER NWRN WYOMING ARRIVES. FURTHERMORE ALSO REMOVED
MENTION OF ISOLATED RAIN SHOWERS ON THE PLAINS EARLY THIS MORNING.
THE LAST OF THE SHOWERS OVER SRN WASHINGTON AND NRN LINCOLN
COUNTIES HAVE SINCE DISSIPATED AND SKIES HAVE QUICKLY CLEARED IN
THIS AREA. CLEARING WILL BE SHORT-LIVED AS HIGH CLOUDS WILL SPREAD
OVER THIS AREA AS WELL LATER THIS MORNING. NO OTHER CHANGES TO THE
FORECAST AT THIS TIME.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 342 AM MST SUN JAN 25 2015

NORTHWEST FLOW ALOFT REMAINS STRONG THIS MORNING THE PRODUCT A
TIGHT THERMAL/PRESSURE GRADIENT BETWEEN A DEEP UPPER TROUGH TO
OUR EAST AND A HIGH PRESSURE BUILDING TO OUR WEST. SPOKES OF JET
ENERGY AND MOISTURE ROTATING AROUND THE TROUGH CONTINUES TO
GENERATE A COUPLE NW-SE BANDS OF LIGHT RAIN/SNOW OVER EASTERN
PORTIONS OF THE CWA AT THIS HOUR. POCKETS OF LIGHT SNOWFALL ALSO
OCCURRING OVER THE HIGHER MTN ELEVATIONS. IN ADDITION INCREASING
MTN TOP STATIC STABILITY COMBINED WITH A MARGINAL MEAN STATE
CRITICAL LAYER CONTINUE TO TRANSPORT DOWNWARD STRONG MOMENTUM
ALOFT RESULTING IN GUSTS IN THE 45-55 MPH RANGE UP AROUND
TIMBERLINE AND HIGHER EAST SLOPES OF THE FRONT RANGE. GUSTY NWLY
WINDS ALSO OCCURRING IN THE LOWER FOOTHILLS AND ACROSS NORTHERN
PORTIONS OF THE SOUTH PARK WHERE PORTIONS OF THE U.S. HIGHWAY 285
WAS CLOSED DUE TO BLOWING SNOW AND POOR VISIBILITY. AT LAST CHECK
THE HIGHWAY HAS BEEN REOPENED.

FOR TODAY IN THE SHORT TERM...SHOULD SEE THE SPOTTY LIGHT PRECIP
ON THE PLAINS COMING TO AN BY MID-MORNING AS THE STRANDS OF
SLANTWISE LIFT AND INSTABILITY GENERATED BY THE TAIL END OF A
PASSING JET MAXIMA EXITS THE AREA. FURTHERMORE THE GUSTY AND AT
TIMES STRONG W/NWLY WINDS IN AND NEAR THE FRONT RANGE SHOULD ALSO
GRADUALLY WEAKEN TODAY AS THE CROSS STATE PRESSURE GRADIENT
FLATTENING OUT...THE MOUNTAIN WAVE BREAKS DOWN AND THE FLOW ALOFT
DECREASES. CLEARING WAS NOW UNDERWAY BUT LATER THIS MORNING/EARLY
THIS AFTERNOON COULD SEE SKIES FILL AGAIN WITH BANDS OF HIGH
CLOUD ACCORDING TO NAM AND WRF SYNTHETIC SATELLITE IMAGERY. CAN
SEE THESE CLOUDS ON SATELLITE RACING SOUTHWARD OVER CNTRL MONTANA
AND NRN WYOMING. DON`T BELIEVE THEY/LL HAVE MUCH IMPACT ON TEMPS
TODAY. SPEAKING OF TEMPERATURES...THE WARMUP CONTINUES WITH HIGHS
ON THE PLAINS IN THE MID TO UPPER 50S WITH LOWER 50S ACRS THE NERN
CORNER. 30S AND LOWER 40S EXPECTED IN THE HIGH COUNTRY.
TONIGHT...SKIES CLEAR WITH DRIER AIR SPREADING OVER THE AREA AS
THE HIGH PRESSURE RIDGE OUT WEST MOVES CLOSER. COULD SEE GUSTY WLY
WINDS REDEVELOPING OVERNIGHT ESPLY ABOVE TIMBERLINE AND ON EAST
SLOPES OF THE FRONT RANGE. GUSTS POSSIBLY IN THE 30-50 MPH RANGE.
LOWS TEMPS TONIGHT WILL BE WELL ABOVE AVERAGE WITH WARMEST
READINGS IN BREEZY AREAS NEAR THE FOOTHILLS.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 342 AM MST SUN JAN 25 2015

STRONG HIGH PRESSURE RIDGE ALOFT OVER THE GREAT BASIN WILL SHIFT
INTO COLORADO ON MONDAY BEFORE WEAKENING A BIT AND MOVING INTO
CENTRAL PLAINS LATER ON TUESDAY. THIS WILL RESULT IN TEMPERATURES
WAY ABOVE NORMAL FOR THIS TIME OF YEAR. ACROSS LOWER
ELEVATIONS...TEMPERATURES WILL SOAR WELL INTO THE MID AND UPPER
60S UNDER SUNNY SKIES. NOT QUITE RECORD MATERIAL BUT PRETTY DANG
WARM FOR LATE JANUARY. RECORDS FOR DENVER ON MONDAY IS 73 DEGREES.

ON TUESDAY AS THE RIDGE MOVES EAST...A WEAKENING UPPER TROF MOVES
NORTHEAST FROM THE DESERT SOUTHWEST AND APPROACHES WESTERN
COLORADO.  EXPECT INCREASING MID/HI LEVEL MOISTURE OVER COLORADO
WHICH MAY RESULT IN SOME SLIGHT COOLING ON THE PLAINS. BY LATE IN
THE DAY COULD BE A FEW SHOWERS OVER THE MOUNTAINS AS MOISTURE
DEEPENS A BIT. STILL LOW POPS IN THE MOUNTAINS WITH UNFAVORABLE
SOUTHWEST MOUNTAIN TOP FLOW.

THE TROF MOVES OVER COLORADO ON WEDNESDAY WHICH SHIFTS THE FLOW
ALOFT MORE WESTERLY AND A BETTER OROGRAPHIC COMPONENT INTO THE
MOUNTAINS LEADING TO A CHANCE OF SNOW SHOWERS. A WEAK COLD FRONT
WILL ALSO MOVE ACROSS THE PLAINS WITH CONTINUED COOLING YET LOOKS
DRY WITH DOWNSLOPE FLOW.

SPLIT FLOW REGIME SETS UP BY LATE IN THE WEEK AS NEXT PACIFIC
STORY SYSTEM MOVES IN OFF THE SOUTHERN CALIFORNIA COAST AND
SPREADS AMPLE MOISTURE INTO THE DESERT SOUTHWEST AND SNEAKS INTO
THE COLORADO MOUNTAINS LATE THURSDAY AND FRIDAY. A WEAK NORTHERN
BRANCH TROF AND COLD FRONT MOVES ACROSS NORTHEAST COLORADO ON
FRIDAY WITH MORE COOLER TEMPERATURES AND A SLIGHT CHANCE FOR
SHOWERS. THE GFS HAS BACKED OFF ON SOME SIGNIFICANT PRECIP OVER
NORTHEAST COLORADO AS IT IS NOW SHOWING A WEAKER TROF MORE LIKE
THE EUROPEAN SOLUTION. STILL FAIRLY CONVOLUTED SO WILL STICK WITH
LOW POPS IN THE LATER PERIODS. TEMPERATURES WILL FALL BACK TO
SEASONAL NORMALS FOR THURSDAY THROUGH SATURDAY.

&&

.AVIATION...(FOR THE TAFS THROUGH 18Z MONDAY MORNING)
ISSUED AT 951 AM MST SUN JAN 25 2015

MAIN CONCERN IS WIND DIRECTION THROUGH THE REST OF TODAY. CURREST
WEST/SOUTHWEST WINDS UNDER 10 KTS AT KDEN AND KAPA WILL MOST
LIKELY TRANSITION TO A NORTHWESTERLY COMPONENT FOR MOST OF THE
AFTERNOON AS DAYTIME HEATING IMPROVES MIXING. AS TEMPERATURES WARM
INTO THE MID 50S SHOULD SEE A STRONGER NORTHWEST COMPONENT
DEVELOPING WITH BETTER MIXING AND GUSTS OF 20-26 KNOTS POSSIBLE.
BY 01Z WINDS ARE EXPECTED TO TRANSITION BACK TO NORMAL
SOUTH/SOUTHWESTERLIES AROUND 8-13 KNOTS. STILL SOME CHANCE WINDS
COULD BECOME LIGHT/VARIABLE IF CONVECTIVE TEMPS OF 55-58F DEGREES ARE
NOT REACHED.

VFR CONDITIONS WILL PERSIST WITH ONLY SCT-BKN CLOUDS ABOVE 8000
FEET. THE MID LEVEL CLOUDS WILL CONTINUE TO PUSH EAST THROUGH 20Z
WITH MOST CLOUDS ABOVE 20 THOUSAND FEET AGL BY 20Z...THEN CLEARING
OVERNIGHT.

&&

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

$$

UPDATE...BARJENBRUCH
SHORT TERM...BAKER
LONG TERM...ENTREKIN
AVIATION...BARJENBRUCH


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