Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 281655
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
955 AM MST SAT FEB 28 2015

.UPDATE...
ISSUED AT 941 AM MST SAT FEB 28 2015

STUBBORN FOG LINGERING OVER PARTS OF DENVER SO WL ADD PATCHY
COVERAGE IN THE ZONES THROUGH EARLY AFTERNOON. ALSO ADJUSTED THE
POPS AND POTENTIAL SNOW AMOUNTS DOWNWARD SLIGHTLY THROUGH THROUGH
THIS AFTN. SPATIAL CROSS-SECTIONS KEEP A DRY MID LAYER 650-750
MB...THROUGH 00Z WHICH MAY LIMIT SNOW POTENTIAL SOMEWHAT THIS
AFTERNOON.

&&

.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 429 AM MST SAT FEB 28 2015

WILL SEE CLOUD COVER INCREASING FROM THE SOUTH THROUGH THE EARLY
MORNING HOURS AS HIGH LEVEL MOISTURE INCREASES. AS CLOUDINESS
INCREASES...TEMPERATURES WILL STAY COLD THROUGH THE DAY. THE
CLOUDINESS WILL BE ASSOCIATED WITH THE DEFORMATION ZONE DOWNSTREAM
FROM A DEVELOPING UPPER TROUGH OVER CALIFORNIA AND NEVADA. AT THE
SAME TIME THE UPPER LEVEL JET WILL BE ARCING ACROSS COLORADO
HELPING TO LIFT THE MID-LEVEL MOISTURE PRESENTLY OVER NORTHERN
ARIZONA AND NORTHERN NEW MEXICO. THE HEAVIEST SNOWFALL FROM THIS
SYSTEM IS EXPECTED TO BE OVER THE SOUTHWEST PART OF THE
STATE...BUT LIGHT SNOW WILL EXTEND OVER THE NORTHERN MOUNTAINS AND
EVENTUALLY ACROSS THE NORTHEAST COLORADO PLAINS TONIGHT. MOUNTAIN
AREAS COULD SEE 2 TO 5 INCHES OF SNOW TODAY AND ANOTHER 2 TO 4
INCHES TONIGHT...MAINLY OVER ZONE 34. NO PERIOD OF INTENSE SNOW IS
EXPECTED...SO WILL NOT ISSUE ANY HIGHLIGHTS AT THIS TIME.

THE PLAINS COULD SEE UP TO A COUPLE INCHES OF SNOW THROUGH THE
EVENING AND OVERNIGHT...BUT IT IS DIFFICULT TO TELL HOW FAR NORTH
ANY SNOW ON THE PLAINS WILL EXTEND. ANOTHER COLD DAY AND COLD
NIGHT WILL RESULT AS THE ARCTIC AIRMASS REMAINS WELL ENTRENCHED
OVER NORTHEAST COLORADO.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 429 AM MST SAT FEB 28 2015

WSW FLOW ALOFT WILL CONTINUE OVER THE AREA SUN THRU SUN NIGHT AS AN
UPPER LEVEL LOW REMAINS OVER SRN CALIFORNIA.  CROSS-SECTIONS SHOW
VARYING AMOUNTS OF MOISTURE IN THE MTNS WITH ONLY SOME MINOR MID LVL
ASCENT WITH FAIRLY UNSTABLE LAPSE RATES.  WILL SEE PERIODS OF LIGHT
SNOW HOWEVER AT THIS POINT ACCUMULATIONS SHOULD STAY BLO ADVISORY
CRITERIA IN MOST AREAS.  AT LOWER ELEVATIONS THERE WILL BE WEAK
UPSLOPE FLOW OVER NERN CO WITH QUITE A BIT OF LOW LVL MOISTURE.
WITH WK MID LVL ASCENT THERE WILL BE A CHC OF LIGHT SNOW MAINLY IN
AND NR THE FOOTHILLS.  AS FOR HIGHS WILL KEEP READINGS IN THE LOWER
TO MID 20S OVER NERN CO.  FOR SUN NIGHT THE LOW LVL FLOW WILL BECOME
MORE SLY WITH STILL SOME WK ASCENT OVER THE PLAINS SO WILL MENTION A
CHC OF LIGHT SNOW MAINLY FM AKRON SOUTH TOWARDS LIMON.

ON MON THE UPPER LEVEL LOW OVER SRN CALIFORNIA WILL BEGIN TO MOVE
ENE WITH INCREASING SWLY FLOW ALOFT OVER THE AREA.  CROSS-SECTIONS
SHOW INCREASING MOISTURE IN THE MTNS WITH FAVORABLE LAPSE RATES
ALONG WITH SOME MID LVL ASCENT SO SHOULD SEE PERIODS OF SNOW IN
AREAS FAVORED BY SWLY FLOW.  OVER NERN CO A SFC LOW WILL DVLP WITH
GUSTY SLY WINDS OVER THE PLAINS.  WITH SOME MID LVL ASCENT AND
DECENT LAPSE RATES COULD SEE A FEW -SHSN AS WELL.  AS FOR HIGHS
SHOULD SEE WARMER TEMPS OVER NERN CO WITH READINGS IN THE 35 TO 40
DEGREE RANGE.

BY MON NIGHT THE REMNANTS OF THE UPPER LEVEL LOW WILL MOVE ENE
ACROSS THE AREA AS SFC LOW PRES REMAINS SOMEWHERE OVER ERN CO.  LAST
NIGHT THIS LOW WAS MORE OVER SERN CO WHILE TONIGHT ITS FCST OVER
NERN CO.  MEANWHILE A STG CDFNT IS NOW 6-12 HOURS SLOWER THAN WHAT
WAS SHOWN PREVIOUSLY.  WITH RATHER STG MID LVL QG ASCENT AND STEEP
LAPSE RATES FCST OVER NRN CO MON NIGHT...IF THE SFC LOW ENDS UP
OVER SERN CO AND THE CDFNT MOVES SOUTH FASTER THAN CURRENTLY SHOWN
THEN COULD END UP WITH A DECENT SNOW EVENT MON NIGHT INTO EARLY
TUE FM THE MTNS ACROSS THE NRN FOOTHILLS AND ADJACENT PLAINS.
RIGHT NOW THE HEAVIEST PCPN IS FCST TO BE IN THE NRN MTNS AND OVER
WY HOWEVER IT WOULD NOT BE A TOTAL SURPRISE IF ITS ENDS UP BEING
FURTHER SOUTH.

ON TUE THE INITIAL DISTURBANCE WILL MOVE QUICKLY EAST OF THE AREA IN
THE MORNING AS A SECONDARY UPPER LEVEL TROUGH MOVES ACROSS THE RGN
TUE AFTN THRU TUE NIGHT FM THE NW. MEANWHILE MUCH COLDER AIR WILL
MOVE ACROSS NERN CO TUE MORNING WITH FAVORABLE UPSLOPE FLOW THRU
TUE EVENING. CROSS-SECTIONS SHOW ABUNDANT MOISTURE WITH MID LVL
ASCENT AS WELL SO SHOULD SEE A GOOD CHC OF SNOW THRU THE DAY INTO
TUE NIGHT. IN THE MTNS OROGRAPHICS WILL BECOME MORE FAVORABLE SO
SHOULD SEE PERIODS OF SNOW AS WELL. AS FOR HIGHS READINGS OVER
NERN CO WILL PEAK IN THE MORNING AS THEN STEADILY FALL THROUGH THE
DAY WITH READINGS IN THE TEENS BY AFTN.

BY WED THE UPPER LEVEL TROUGH WILL GRADUALLY MOVE SE OF THE AREA BY
AFTN AS COLD SFC HIGH PRES RESIDES OVER THE AREA.  CROSS-SECTIONS
STILL SHOW QUITE A BIT OF MOISTURE THRU MIDDAY WITH WK UPSLOPE FLOW
THUS MAY SEE A CHC OF LIGHT SNOW MAINLY ALONG AND NR THE FOOTHILLS
AND IN THE MTNS.  LATEST 850-700 MB TEMPS WOULD KEEP HIGHS IN THE
LOWER TO MID TEENS OVER THE PLAINS.

FOR THU AND FRI DRY NWLY FLOW ALOFT WILL BE OVER THE RGN.  TEMPS
SHOULD BEGIN TO MODERATE WITH HIGHS IN THE 30S ON THU WITH 40S BY
FRI OVER NERN CO.

&&

.AVIATION...(FOR THE TAFS THROUGH 18Z SUNDAY MORNING)
ISSUED AT 941 AM MST SAT FEB 28 2015

OCNL MVFR VSBY RESTRICTION ASSOCIATED WITH STUBBORN FOG MAY LINGER
INTO EARLY THIS AFTN AT KDEN AND KBJC. THIS AFTN...THE WIND WILL
SWITCH FM WNWLY TO NELY AND SOME LIGHT SNOW LATE IN THE DAY AS
MOISTURE IN MID LEVELS STARTS TO INCREASE FROM THE SOUTH AND WEST.
AREAS OF SNOW WILL INCREASE IN COVERAGE...BRINGING MVFR CONDITIONS
DOWN TO OCNL IFR TONIGHT. SNOW ACCUMULATIONS COULD BE ONE OR TWO
INCHES...HIGHEST AT KBJC AND KAPA.

&&

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

$$

UPDATE...COOPER
SHORT TERM...DANKERS
LONG TERM...RPK
AVIATION...COOPER


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