000
FXUS65 KBOU 031658
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
958 AM MST TUE MAR 3 2015

.UPDATE...
ISSUED AT 958 AM MST TUE MAR 3 2015

COLD FRONT HAS PUSHED THROUGH EASTERN COLORADO ALREADY THIS
MORNING. TEMPERATURES ARE EXPECTED TO SLOWLY FALL THROUGH THE
DAY. UPDATED TEMPERATURE GRIDS TO REFLECT THE COLDER START TO THE
MORNING.

LIGHT SNOW HAS FORMED OVER THE DENVER AREA DUE TO UPSLOPE BEHIND
THE FRONT. EXPECT LIGHT SNOW TO LINGER THROUGH THE DAY WITH SNOW
ACCUMULATION AROUND AN INCH WITH SLIGHTLY MORE POSSIBLE NEAR THE
FOOTHILLS AND UNDER SNOW BANDS. THE HRRR AND OTHER SHORT TERM
MODELS STILL HAVE NOT CAUGHT ON TO THE LIGHT SNOW THIS
MORNING...SO EXPECT SNOW AMOUNTS TO BE A LITTLE HIGHER THAN IN
THE MODELS THROUGH THIS AFTERNOON.

A BAND OF SLIGHTLY HEAVIER SNOW IS OVER BOULDER...LARIMER AND
WELD COUNTIES. MORNING SOUNDING AT KDNR SHOWED STEEP LAPSE RATES
UP TO ABOUT 550 MB. SO ADDITIONAL SNOW SHOWERS WILL REMAIN
POSSIBLE THROUGH THE DAY WHICH WILL PRODUCE HEAVIER SNOW FOR A
SHORT TIME.

HEAVIEST SNOW AND BEST COVERAGE IS STILL EXPECTED LATE THIS
AFTERNOON AND TONIGHT AS AN UPPER LEVEL TROUGH PROVIDES ADDITIONAL
LIFT. IN ADDITION TO THIS...A SECONDARY PUSH FROM THE NORTH MAY
PRODUCE A LINE OF HEAVIER SNOW THAT WILL MOVE SOUTH ACROSS THE
AREA. WILL KEEP WINTER WEATHER HIGHLIGHTS AS IS.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 446 AM MST TUE MAR 3 2015

MODELS CONTINUE A TREND OF SLIGHTLY SLOWING THE INCOMING SYSTEM.
THIS LOOKS CORRECT SO THE MAIN ADJUSTMENT HAS BEEN TO SLOW THINGS
DOWN BY 3-6 HOURS. COLD FRONT COMING ACROSS THE BORDER AND SHOULD
BE THROUGH DENVER BY ABOUT 7 AM. ONE GOOD SHOWER BAND HAS FORMED
AROUND CHEYENNE BUT IS TIED TO THE UPPER FEATURES...NOT THE COLD
FRONT. AIRMASS IS ACTUALLY DRYING FROM THE WEST OVERALL AT THIS
TIME...THOUGH THERE ARE STILL SOME SHALLOW SHOWER BANDS AND ENOUGH
MOISTURE FOR OROGRAPHIC SNOW TO CONTINUE ON THE RIDGES. SO FOR
THIS MORNING THE LOW LEVELS WILL BECOME MORE SUPPORTIVE OF
SHOWERS...BUT THERE WILL BE LESS UPPER LEVEL SUPPORT. I REDUCED
THE COVERAGE OF SHOWERS ON THE PLAINS THIS MORNING BUT THERE WILL
LIKELY STILL BE SOME. THIS AFTERNOON THE LOW LEVEL COLD AIR
DEEPENS WHILE UPSLOPE CONVERGENCE DEVELOPS ON THE EAST SIDE OF THE
FRONT RANGE. THERE IS COOLING ALOFT WITH DESTABILIZATION AND THE
NEXT AREA OF LIFT MOVES INTO THE MOUNTAINS AND NORTHERN
AREAS...AND ACROSS THE REST OF OUR AREA BY EARLY EVENING. PRETTY
GOOD CONSENSUS ON WIDESPREAD 2-3 INCHES OF SNOW AS THIS FEATURE
PASSES IN THE LATE AFTERNOON AND OVERNIGHT...PLUS THE OROGRAPHIC
INFLUENCES. ENVIRONMENT WILL BE FAVORABLE FOR A GOOD RESPONSE TO
THE LOW LEVEL CONVERGENCE THIS EVENING...NOT SUPER UNSTABLE BUT A
DEEP LAYER OF WEAK STABILITY. FOR THIS REASON PLANNING ON DECENT
ENHANCEMENT IN AND NEAR THE FOOTHILLS...AND ALSO A PERIOD OF
PRETTY GOOD OROGRAPHIC SNOW IN THE HIGHER MOUNTAINS IN THE LATE
AFTERNOON/EARLY EVENING WHILE THERE IS BOTH INSTABILITY AND WIND.
EXTENDED THE MOUNTAIN WARNING THROUGH TONIGHT...AND ISSUED AN
ADVISORY FOR THE FOOTHILLS...DENVER/BOULDER AND DOUGLAS AND ELBERT
COUNTIES WHERE THIS ENHANCEMENT WILL LIKELY CREATE SEVERAL HOURS OF
MODERATE TO HEAVY SNOW. HOPING THE HEAVIEST TIME FOR DENVER WILL
BE AFTER RUSH HOUR...BUT AT A MINIMUM THINGS WILL LIKELY BE GOING
DOWNHILL WITH SOME SNOWFALL AND COOLING TEMPERATURES. AREAS JUST
EAST OF THE ADVISORY MAY WIND UP NEEDING ONE...ESPECIALLY IF THE
WIND ON THE PLAINS LASTS LONGER THAN EXPECTED. THE CURRENT
EXPECTATION IS THAT THE STRONGEST WINDS WILL OCCUR BEFORE THERE IS
MUCH SNOW ON THE GROUND.

SNOW WILL BE DECREASING FROM NORTH TO SOUTH LATE TONIGHT THOUGH
THERE WILL LIKELY STILL BE LIGHT SNOW IN DENVER ALL NIGHT. BUMPED
TEMPERATURES UP SLIGHTLY THIS MORNING FOR THE FRONT TIMING...BUT
THEY WILL BE COLDER THIS AFTERNOON.

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 446 AM MST TUE MAR 3 2015

MAIN AXIS OF UPPER LEVEL TROUGH WILL BE MOVING ACROSS ERN CO WED
MORNING AND THEN BE EAST OF AREA BY 18Z.  CROSS-SECTIONS STILL SHOW
WEAK UPSLOPE COMPONENT THRU MID MORNING WITH QUITE A BIT OF MOISTURE
SO THERE WILL LIKELY BE SOME LIGHT SNOW FM DENVER SOUTH ACROSS THE
PALMER DIVIDE INTO THE FOOTHILLS.  EXPECT MOST OF THIS ACTIVITY WILL
GRADUALLY END BY MID TO LATE MORNING. OTHERWISE DRIER AIR WILL
SPREAD ACROSS THE RGN BY AFTN WITH DECREASING CLOUDS AND ONLY A A
SLIGHT CHC OF -SN IN THE MTNS. AFTN HIGHS WILL BE WELL BLO NORMAL
AS READINGS OVER NERN CO RANGE FROM THE UPPER TEENS TO LOWER 20S.

ON THU A WK DISTURBANCE WILL MOVE ACROSS THE AREA IN NW FLOW ALOFT
HOWEVER THIS FEATURE HAS NO MOISTURE WITH IT SO WILL KEEP FCST DRY.
AS FOR HIGHS 850-700 MB TEMPS RISE AROUND 10-11 DEGREES C BY LATE
AFTN SO SHOULD SEE READINGS WRM INTO THE 35 TO 40 DEGREE RANGE OVER
NERN CO WITH LOWER TO MID 40S OVER THE FAR NERN CORNER.  FOR FRI DRY
NWLY FLOW ALOFT WILL CONTINUE WITH 850-700 MB TEMPS RISING ANOTHER 3-
DEGREES C WHICH SHOULD ALLOW FOR HIGHS TO REACH THE 45 TO 50 DEGREE
RANGE OVER NERN CO.

OVER THE WEEKEND NWLY FLOW ALOFT WILL REMAIN OVER THE AREA WITH SOME
MOISTURE EMBEDDED IN THE FLOW.  THUS MAY SEE A CHC OF LIGHT SNOW IN
THE MTNS ESPECIALLY SAT AFTN AND EVENING AS A WK DISTURBANCE MOVES
ACROSS. OVER NERN CO A COOL FNT WILL MOVE ACROSS LATE FRI NIGHT INTO
SAT.  CROSS-SECTIONS DO NOT SHOW MUCH MOISTURE WITH THIS FNT SO WILL
KEEP FCST DRY FOR NOW.  HIGHS WILL BE IN THE LOWER TO MID 40S OVER
THE PLAINS ON SAT AND THEN SLIGHTLY WARMER ON SUN WITH READINGS IN
THE 45 TO 50 DEGREE RANGE.

FOR EARLY NEXT WEEK THE FLOW ALOFT WILL CONTINUE NWLY WITH NOT MUCH
MOISTURE SHOWN SO WILL NOT MENTION ANY PCPN.  TEMPS WILL CONTINUE TO
MODERATE WITH READINGS IN THE LOWER TO MID 50S ACROSS NERN CO ON MON.

&&

.AVIATION...(FOR THE TAFS THROUGH 18Z WEDNESDAY MORNING)
ISSUED AT 958 AM MST TUE MAR 3 2015

LIGHT SNOW WILL SLOWLY INCREASE OVER THE DENVER AREA AFTER 21Z.
VISIBILITY IS EXPECTED TO REMAIN 2-5 MILES THROUGH 21Z AND THEN
LOWER. CEILINGS ARE EXPECTED TO STAY BELOW 2000 TODAY AND BE LOWER
TONIGHT. POCKETS OF HEAVIER SNOW MAY REDUCE VISIBILITY TO A HALF
MILE FOR A SHORT TIME.

NORTH TO NORTHEAST WINDS UP TO 20 KNOTS WILL SLOWLY DECREASE
THROUGH THE NEXT 24 HOURS. WINDS MAY SHIFT EASTERLY FOR A SHORT
TIME BUT WILL BOUNCE BACK TO THE NORTH-NORTHEAST WITH A SECOND
PUSH FROM THE NORTH AROUND 03Z.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 2 PM THIS AFTERNOON TO 5 AM MST
WEDNESDAY FOR COZ035-036-039>041.

WINTER STORM WARNING UNTIL 5 AM MST WEDNESDAY FOR COZ031-033.

&&

$$

UPDATE...MEIER
SHORT TERM...GIMMESTAD
LONG TERM...RPK
AVIATION...MEIER