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000
FXUS65 KBOU 300217
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
817 PM MDT FRI APR 29 2016

.UPDATE...
ISSUED AT 817 PM MDT FRI APR 29 2016

THE UPPER LEVEL LOW WILL BE MOVING OUT OF THE STATE TONIGHT AND
THE WEAK UPWARD FORCING OVER THE NORTHWEST QUADRANT OF THE LOW
WILL BE DIMINISHING. LIGHT SNOW CONTINUES OVER THE NORTHEAST
PLAINS...BUT ACCUMULATIONS HAVE BEEN LIGHT UP TO THIS POINT. AREAS
ALONG THE FRONT RANGE HAVE BEEN FREE OF PRECIPITATION OVER THE
PAST FEW HOURS...AND SNOW IN THE MOUNTAINS HAS BECOME
SPOTTY...BASED ON A REVIEW OF VARIOUS WEB CAMERAS. THE HRRR AND
RAP MODELS SHOW THAT SNOW WILL CONTINUE DECREASING THROUGH
TONIGHT...SO IT LOOKS LIKE THE ACCUMULATING PART OF THE STORM IS
OVER. WILL BE CANCELLING THE ADVISORIES IN THE MOUNTAINS AND THE
PALMER DIVIDE AS LITTLE MORE THAN 1 INCH OF ACCUMULATION IS
EXPECTED OVERNIGHT. WITH THE MOIST AIRMASS IN PLACE OVER THE
PLAINS AND LIGHT NORTHERLY FLOW EXPECTED TO CONTINUE
OVERNIGHT...HAVE BUMPED UP THE COVERAGE OF FOG WHICH IS EXPECTED
TO DEVELOP ACROSS NORTHEAST COLORADO. THE FORECAST AREA WILL BE
UNDER WEAK NORTHERLY RETURN FLOW THROUGH TOMORROW...AND DIURNAL
HEATING SHOULD LEAD TO RE-DEVELOPMENT OF RAIN/SNOW SHOWERS
TOMORROW. WILL NOT MAKE ANY CHANGES TO THE THAT FORECAST PERIOD
FOR NOW.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 415 PM MDT FRI APR 29 2016

NEGATIVE TILT UPPER TROUGH ANCHORED TO A CLOSED LOW PRESENTLY OVER
THE SAN JUAN MTNS IN SWRN COLORADO IS PROGGED TO SWING NORTHEASTWARD
OVER NORTHERN AND EASTERN COLORADO OVERNIGHT. A LIGHT TO MODERATE
SOUTHEASTERLY FLOW AHEAD OF THIS TROUGH CONTINUES TO PROVIDE AMPLE
MOISTURE AND LIFT NECESSARY TO GENERATE WIDESPREAD PRECIPITATION
OVER NORTHEAST COLORADO TODAY. PRECIPITATION HAS PRIMARILY BEEN SNOW
SINCE LATE THIS MORNING...ALTHOUGH THERE ARE STILL POCKETS OF
RAINFALL ACROSS FAR NORTHEAST COLORADO...SUCH AS THE MODERATE
RAINFALL AT STERLING. HOWEVER WITH TEMPERATURES JUST ABOVE FREEZING
AND ENOUGH SOLAR ENERGY FILTERING THROUGH THE OVERCAST...THERE HAS
NOT BEEN SNOW ACCUMULATION ON THE PLAINS...EXCEPT ALONG THE PALMER
DIVIDE IN DOUGLAS AND ELBERT COUNTIES. RECEIVED A SNOW DEPTH REPORT
OF 14 INCHES NEAR THE TOWN OF MATHESON SOUTHEAST CORNER OF ZONE 41.
THIS LOOKS VERY LOCALIZED. SNOW AMOUNTS ACROSS THIS ZONE GENERALLY
IN THE 3-8 INCH RANGE. AS FOR THE FRONT RANGE MTNS...FOOTHILLS AND
SOUTH PARK ZONES UNDER THE WINTER STORM WARNING...SNOW ACCUMS WITH
THIS STORM MARGINALLY REACHED WARNING CRITERIA. HIGH COUNTRY ROAD
WAYS ALSO SAW LITTLE IF ANY SNOW ACCUMULATION.

RADAR SHOWS A SHARP SOUTHERN EDGE TO THE PRECIP BAND LIFTING NORTH
OVER NERN COLORADO ATTM. THIS EDGE HAS REACHED SRN LINCOLN COUNTY.
AND IS EXPECTED TO THE INTERSTATE 70 CORRIDOR AROUND DENVER BY 02Z
THIS EVENING...AND MUCH SOONER THAN THAT FOR THE LIMON AREA. WITH
COOLING TEMPS AND A LOWERING SUN ANGLE...THERE`S A BETTER FOR SNOW
ACCUMULATION ON THE PLAINS...AS WELL AS THE EAST FACE OF THE FRONT
RANGE DURING THIS PERIOD. HOWEVER ADDITIONAL SNOW AMOUNTS ON THE
FRONT RANGE AND SOUTH PARK WOULD NOT WARRANT HOLDING ONTO THE WINTER
STORM WARNING. A WINTER WEATHER ADVISORY WOULD SUFFICE. IT`LL STILL
RUN UNTIL 06Z TONIGHT. LASTLY ADDED FOG TO THE PLAINS AND FOOTHILLS
FORECAST FOR THE REMAINDER OF THE NIGHT. VSBYS ANYWHERE FROM A
QUARTER MILE TO 4 MILES THROUGH THE EVENING.

ON SATURDAY...MODELS SHOW THE UPPER LOW STILL IMPACTING NORTHEAST
COLORADO FOR MOST OF THE DAY. MOISTURE WRAPPING AROUND THE BACK SIDE
OF THIS LOW AND A COOL N-NWLY WIND SHOULD KEEP THE FCST AREA
UNSEASONABLY COOL AND UNSETTLED. QG VV FIELDS SHOW A LOBE OF MID-
LEVEL LIFT SWINGING DOWN FROM SERN WYOMING DURING THE MORNING LIKELY
RESULTING IN AN UPTURN IN PRECIPITATION COVERAGE ACROSS THE NERN
PLAINS AND NRN FRONT RANGE. LIGHT SNOW ACCUMULATIONS A POSSIBILITY.
LATER IN THE DAY...THE CWA GRADUALLY COMES UNDER THE INFLUENCE OF
DRIER AIR AND SUBSIDENCE AS THE UPPER LOW CONTINUES TO PULL AWAY.
THERE PRECIP CHANCES SHOULD LIKEWISE DECREASE FROM SOUTHWEST TO
NORTHEAST DURING THE AFTERNOON. TEMPERATURES NEXT 24 HOURS WELL
BELOW AVERAGE WITH HIGH TEMPS ON SATURDAY GENERALLY 3-6 DEG F WARMER
THAN THOSE TODAY.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 415 PM MDT FRI APR 29 2016

THERE WILL BE A BREAK BETWEEN SYSTEMS SATURDAY NIGHT AND SUNDAY
MORNING. HOWEVER IT WILL REMAIN CLOUDY WITH LOTS OF MOISTURE AND A
SHALLOW UNSTABLE LAYER NEAR THE GROUND...SO A LOW CHANCE OF LIGHT
SHOWERS OR DRIZZLE IS IN ORDER. THERE MAY BE WIDESPREAD DRIPPINESS
BUT NOT EXPECTING MUCH IN THE WAY OF ACCUMULATION. THERE WAS SOME
THOUGHT OF FREEZING DRIZZLE EARLIER...BUT IT APPEARS TEMPERATURES
WILL GENERALLY BE ABOVE FREEZING WITH WARM AND WET ROADS. IF THERE
WERE UPSLOPE WINDS I WOULD BE CONCERNED WITH A RIBBON OF
FOG/FREEZING DRIZZLE IN THE FOOTHILLS BUT IT LOOKS LIKE THIS WILL
NOT BE THE CASE.

THERE IS A LITTLE BETTER AGREEMENT AND DEFINITION OF A WAVE
PASSING OVER AND SOUTH OF US ON SUNDAY INTO MONDAY. THE BEST LIFT
SHOULD BE TO THE SOUTH...AND IS GENERALLY WEAK...BUT IT WILL BE
WORKING ON A PRETTY FAVORABLE ENVIRONMENT WITH PLENTY OF MOISTURE
AND A SHALLOW UNSTABLE LAYER. SO IT MAY NOT BE HARD TO GENERATE
WIDESPREAD LIGHT PRECIPITATION AGAIN. RAISED POPS FOR THIS
PERIOD...NOT READY TO COMMIT TO THE WIDESPREAD PRECIPITATION
EVERYWHERE YET. TEMPERATURES SHOULD BE A LITTLE WARMER THAN THEY
ARE NOW AND PRECIPITATION SHOULD BE LIGHTER...SO THERE SHOULD BE LESS
IMPACT THAN WHAT WE ARE SEEING TODAY. STILL PROBABLY SOME SNOW
THOUGH...AT LEAST ABOVE 5000 FEET. THERE ARE TIMING DIFFERENCES ON
THE CLEARING OF THIS SYSTEM ON MONDAY...TRENDS ARE TOWARD MOVING
THE HIGHER LEVEL LIFT OUT EARLY MONDAY BUT WITH LOW LEVEL MOISTURE
LINGERING MUCH OF THE DAY.

A RIDGE WILL BUILD OVER US FOR THE REST OF THE WEEK. A WRINKLE
THAT DEVELOPED IN LAST NIGHTS ECMWF IS PERSISTING TODAY...A LOW
THAT DEVELOPS OVER SASKATCHEWAN AND DROPS INTO THE WESTERN U.S.
IF THIS DOES OCCUR...AND IT IS A MINORITY OPINION...IT IS PROBABLY
NOT MUCH OF A WEATHER MAKER BUT COULD HOLD BACK THE WARMING AND
GENERATE SOME CLOUD COVER...MAINLY AFFECTING TUESDAY AND
WEDNESDAY. PRETTY WARM BY THE END OF THE WEEK...WE COULD BE BACK
NEAR 80. THERE IS INCREASING CONSENSUS ON A BIG LOW MOVING INTO
THE WEST FOR NEXT WEEKEND...SO WE COULD BE BACK TO COOL AND WET BY
SUNDAY. WAY TOO EARLY FOR ANY CONFIDENCE OR DETAILS YET...A
PACIFIC SYSTEM WOULD PROBABLY NOT BE REAL COLD...LIKELY WARMER
THAN THE CURRENT SYSTEM.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 817 PM MDT FRI APR 29 2016

SNOW APPEARS TO HAVE COME TO AN END OVER THE DENVER AREA
AIRPORTS FOR THE EVENING...BUT CONTINUING WEAK NORTHERLY FLOW AND
A VERY MOIST AIRMASS WILL LEAD TO THE FORMATION OF FOG DURING THE
OVERNIGHT HOURS. VISIBILITIES COULD DROP TO A HALF MILE OR LESS AT
TIMES. FOG IN THE MORNING WILL GIVE WAY TO SOME MORE RAIN OR SNOW
SHOWERS BY MIDDAY AS DAYTIME WARMING CAUSES THE AIRMASS TO BECOME
SLIGHTLY UNSTABLE.

&&

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

$$

UPDATE...DANKERS
SHORT TERM...BAKER
LONG TERM...GIMMESTAD
AVIATION...DANKERS





000
FXUS65 KBOU 300217
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
817 PM MDT FRI APR 29 2016

.UPDATE...
ISSUED AT 817 PM MDT FRI APR 29 2016

THE UPPER LEVEL LOW WILL BE MOVING OUT OF THE STATE TONIGHT AND
THE WEAK UPWARD FORCING OVER THE NORTHWEST QUADRANT OF THE LOW
WILL BE DIMINISHING. LIGHT SNOW CONTINUES OVER THE NORTHEAST
PLAINS...BUT ACCUMULATIONS HAVE BEEN LIGHT UP TO THIS POINT. AREAS
ALONG THE FRONT RANGE HAVE BEEN FREE OF PRECIPITATION OVER THE
PAST FEW HOURS...AND SNOW IN THE MOUNTAINS HAS BECOME
SPOTTY...BASED ON A REVIEW OF VARIOUS WEB CAMERAS. THE HRRR AND
RAP MODELS SHOW THAT SNOW WILL CONTINUE DECREASING THROUGH
TONIGHT...SO IT LOOKS LIKE THE ACCUMULATING PART OF THE STORM IS
OVER. WILL BE CANCELLING THE ADVISORIES IN THE MOUNTAINS AND THE
PALMER DIVIDE AS LITTLE MORE THAN 1 INCH OF ACCUMULATION IS
EXPECTED OVERNIGHT. WITH THE MOIST AIRMASS IN PLACE OVER THE
PLAINS AND LIGHT NORTHERLY FLOW EXPECTED TO CONTINUE
OVERNIGHT...HAVE BUMPED UP THE COVERAGE OF FOG WHICH IS EXPECTED
TO DEVELOP ACROSS NORTHEAST COLORADO. THE FORECAST AREA WILL BE
UNDER WEAK NORTHERLY RETURN FLOW THROUGH TOMORROW...AND DIURNAL
HEATING SHOULD LEAD TO RE-DEVELOPMENT OF RAIN/SNOW SHOWERS
TOMORROW. WILL NOT MAKE ANY CHANGES TO THE THAT FORECAST PERIOD
FOR NOW.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 415 PM MDT FRI APR 29 2016

NEGATIVE TILT UPPER TROUGH ANCHORED TO A CLOSED LOW PRESENTLY OVER
THE SAN JUAN MTNS IN SWRN COLORADO IS PROGGED TO SWING NORTHEASTWARD
OVER NORTHERN AND EASTERN COLORADO OVERNIGHT. A LIGHT TO MODERATE
SOUTHEASTERLY FLOW AHEAD OF THIS TROUGH CONTINUES TO PROVIDE AMPLE
MOISTURE AND LIFT NECESSARY TO GENERATE WIDESPREAD PRECIPITATION
OVER NORTHEAST COLORADO TODAY. PRECIPITATION HAS PRIMARILY BEEN SNOW
SINCE LATE THIS MORNING...ALTHOUGH THERE ARE STILL POCKETS OF
RAINFALL ACROSS FAR NORTHEAST COLORADO...SUCH AS THE MODERATE
RAINFALL AT STERLING. HOWEVER WITH TEMPERATURES JUST ABOVE FREEZING
AND ENOUGH SOLAR ENERGY FILTERING THROUGH THE OVERCAST...THERE HAS
NOT BEEN SNOW ACCUMULATION ON THE PLAINS...EXCEPT ALONG THE PALMER
DIVIDE IN DOUGLAS AND ELBERT COUNTIES. RECEIVED A SNOW DEPTH REPORT
OF 14 INCHES NEAR THE TOWN OF MATHESON SOUTHEAST CORNER OF ZONE 41.
THIS LOOKS VERY LOCALIZED. SNOW AMOUNTS ACROSS THIS ZONE GENERALLY
IN THE 3-8 INCH RANGE. AS FOR THE FRONT RANGE MTNS...FOOTHILLS AND
SOUTH PARK ZONES UNDER THE WINTER STORM WARNING...SNOW ACCUMS WITH
THIS STORM MARGINALLY REACHED WARNING CRITERIA. HIGH COUNTRY ROAD
WAYS ALSO SAW LITTLE IF ANY SNOW ACCUMULATION.

RADAR SHOWS A SHARP SOUTHERN EDGE TO THE PRECIP BAND LIFTING NORTH
OVER NERN COLORADO ATTM. THIS EDGE HAS REACHED SRN LINCOLN COUNTY.
AND IS EXPECTED TO THE INTERSTATE 70 CORRIDOR AROUND DENVER BY 02Z
THIS EVENING...AND MUCH SOONER THAN THAT FOR THE LIMON AREA. WITH
COOLING TEMPS AND A LOWERING SUN ANGLE...THERE`S A BETTER FOR SNOW
ACCUMULATION ON THE PLAINS...AS WELL AS THE EAST FACE OF THE FRONT
RANGE DURING THIS PERIOD. HOWEVER ADDITIONAL SNOW AMOUNTS ON THE
FRONT RANGE AND SOUTH PARK WOULD NOT WARRANT HOLDING ONTO THE WINTER
STORM WARNING. A WINTER WEATHER ADVISORY WOULD SUFFICE. IT`LL STILL
RUN UNTIL 06Z TONIGHT. LASTLY ADDED FOG TO THE PLAINS AND FOOTHILLS
FORECAST FOR THE REMAINDER OF THE NIGHT. VSBYS ANYWHERE FROM A
QUARTER MILE TO 4 MILES THROUGH THE EVENING.

ON SATURDAY...MODELS SHOW THE UPPER LOW STILL IMPACTING NORTHEAST
COLORADO FOR MOST OF THE DAY. MOISTURE WRAPPING AROUND THE BACK SIDE
OF THIS LOW AND A COOL N-NWLY WIND SHOULD KEEP THE FCST AREA
UNSEASONABLY COOL AND UNSETTLED. QG VV FIELDS SHOW A LOBE OF MID-
LEVEL LIFT SWINGING DOWN FROM SERN WYOMING DURING THE MORNING LIKELY
RESULTING IN AN UPTURN IN PRECIPITATION COVERAGE ACROSS THE NERN
PLAINS AND NRN FRONT RANGE. LIGHT SNOW ACCUMULATIONS A POSSIBILITY.
LATER IN THE DAY...THE CWA GRADUALLY COMES UNDER THE INFLUENCE OF
DRIER AIR AND SUBSIDENCE AS THE UPPER LOW CONTINUES TO PULL AWAY.
THERE PRECIP CHANCES SHOULD LIKEWISE DECREASE FROM SOUTHWEST TO
NORTHEAST DURING THE AFTERNOON. TEMPERATURES NEXT 24 HOURS WELL
BELOW AVERAGE WITH HIGH TEMPS ON SATURDAY GENERALLY 3-6 DEG F WARMER
THAN THOSE TODAY.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 415 PM MDT FRI APR 29 2016

THERE WILL BE A BREAK BETWEEN SYSTEMS SATURDAY NIGHT AND SUNDAY
MORNING. HOWEVER IT WILL REMAIN CLOUDY WITH LOTS OF MOISTURE AND A
SHALLOW UNSTABLE LAYER NEAR THE GROUND...SO A LOW CHANCE OF LIGHT
SHOWERS OR DRIZZLE IS IN ORDER. THERE MAY BE WIDESPREAD DRIPPINESS
BUT NOT EXPECTING MUCH IN THE WAY OF ACCUMULATION. THERE WAS SOME
THOUGHT OF FREEZING DRIZZLE EARLIER...BUT IT APPEARS TEMPERATURES
WILL GENERALLY BE ABOVE FREEZING WITH WARM AND WET ROADS. IF THERE
WERE UPSLOPE WINDS I WOULD BE CONCERNED WITH A RIBBON OF
FOG/FREEZING DRIZZLE IN THE FOOTHILLS BUT IT LOOKS LIKE THIS WILL
NOT BE THE CASE.

THERE IS A LITTLE BETTER AGREEMENT AND DEFINITION OF A WAVE
PASSING OVER AND SOUTH OF US ON SUNDAY INTO MONDAY. THE BEST LIFT
SHOULD BE TO THE SOUTH...AND IS GENERALLY WEAK...BUT IT WILL BE
WORKING ON A PRETTY FAVORABLE ENVIRONMENT WITH PLENTY OF MOISTURE
AND A SHALLOW UNSTABLE LAYER. SO IT MAY NOT BE HARD TO GENERATE
WIDESPREAD LIGHT PRECIPITATION AGAIN. RAISED POPS FOR THIS
PERIOD...NOT READY TO COMMIT TO THE WIDESPREAD PRECIPITATION
EVERYWHERE YET. TEMPERATURES SHOULD BE A LITTLE WARMER THAN THEY
ARE NOW AND PRECIPITATION SHOULD BE LIGHTER...SO THERE SHOULD BE LESS
IMPACT THAN WHAT WE ARE SEEING TODAY. STILL PROBABLY SOME SNOW
THOUGH...AT LEAST ABOVE 5000 FEET. THERE ARE TIMING DIFFERENCES ON
THE CLEARING OF THIS SYSTEM ON MONDAY...TRENDS ARE TOWARD MOVING
THE HIGHER LEVEL LIFT OUT EARLY MONDAY BUT WITH LOW LEVEL MOISTURE
LINGERING MUCH OF THE DAY.

A RIDGE WILL BUILD OVER US FOR THE REST OF THE WEEK. A WRINKLE
THAT DEVELOPED IN LAST NIGHTS ECMWF IS PERSISTING TODAY...A LOW
THAT DEVELOPS OVER SASKATCHEWAN AND DROPS INTO THE WESTERN U.S.
IF THIS DOES OCCUR...AND IT IS A MINORITY OPINION...IT IS PROBABLY
NOT MUCH OF A WEATHER MAKER BUT COULD HOLD BACK THE WARMING AND
GENERATE SOME CLOUD COVER...MAINLY AFFECTING TUESDAY AND
WEDNESDAY. PRETTY WARM BY THE END OF THE WEEK...WE COULD BE BACK
NEAR 80. THERE IS INCREASING CONSENSUS ON A BIG LOW MOVING INTO
THE WEST FOR NEXT WEEKEND...SO WE COULD BE BACK TO COOL AND WET BY
SUNDAY. WAY TOO EARLY FOR ANY CONFIDENCE OR DETAILS YET...A
PACIFIC SYSTEM WOULD PROBABLY NOT BE REAL COLD...LIKELY WARMER
THAN THE CURRENT SYSTEM.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 817 PM MDT FRI APR 29 2016

SNOW APPEARS TO HAVE COME TO AN END OVER THE DENVER AREA
AIRPORTS FOR THE EVENING...BUT CONTINUING WEAK NORTHERLY FLOW AND
A VERY MOIST AIRMASS WILL LEAD TO THE FORMATION OF FOG DURING THE
OVERNIGHT HOURS. VISIBILITIES COULD DROP TO A HALF MILE OR LESS AT
TIMES. FOG IN THE MORNING WILL GIVE WAY TO SOME MORE RAIN OR SNOW
SHOWERS BY MIDDAY AS DAYTIME WARMING CAUSES THE AIRMASS TO BECOME
SLIGHTLY UNSTABLE.

&&

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

$$

UPDATE...DANKERS
SHORT TERM...BAKER
LONG TERM...GIMMESTAD
AVIATION...DANKERS





000
FXUS65 KBOU 292226
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
426 PM MDT FRI APR 29 2016

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 415 PM MDT FRI APR 29 2016

NEGATIVE TILT UPPER TROUGH ANCHORED TO A CLOSED LOW PRESENTLY OVER
THE SAN JUAN MTNS IN SWRN COLORADO IS PROGGED TO SWING NORTHEASTWARD
OVER NORTHERN AND EASTERN COLORADO OVERNIGHT. A LIGHT TO MODERATE
SOUTHEASTERLY FLOW AHEAD OF THIS TROUGH CONTINUES TO PROVIDE AMPLE
MOISTURE AND LIFT NECESSARY TO GENERATE WIDESPREAD PRECIPITATION
OVER NORTHEAST COLORADO TODAY. PRECIPITATION HAS PRIMARILY BEEN SNOW
SINCE LATE THIS MORNING...ALTHOUGH THERE ARE STILL POCKETS OF
RAINFALL ACROSS FAR NORTHEAST COLORADO...SUCH AS THE MODERATE
RAINFALL AT STERLING. HOWEVER WITH TEMPERATURES JUST ABOVE FREEZING
AND ENOUGH SOLAR ENERGY FILTERING THROUGH THE OVERCAST...THERE HAS
NOT BEEN SNOW ACCUMULATION ON THE PLAINS...EXCEPT ALONG THE PALMER
DIVIDE IN DOUGLAS AND ELBERT COUNTIES. RECEIVED A SNOW DEPTH REPORT
OF 14 INCHES NEAR THE TOWN OF MATHESON SOUTHEAST CORNER OF ZONE 41.
THIS LOOKS VERY LOCALIZED. SNOW AMOUNTS ACROSS THIS ZONE GENERALLY
IN THE 3-8 INCH RANGE. AS FOR THE FRONT RANGE MTNS...FOOTHILLS AND
SOUTH PARK ZONES UNDER THE WINTER STORM WARNING...SNOW ACCUMS WITH
THIS STORM MARGINALLY REACHED WARNING CRITERIA. HIGH COUNTRY ROAD
WAYS ALSO SAW LITTLE IF ANY SNOW ACCUMULATION.

RADAR SHOWS A SHARP SOUTHERN EDGE TO THE PRECIP BAND LIFTING NORTH
OVER NERN COLORADO ATTM. THIS EDGE HAS REACHED SRN LINCOLN COUNTY.
AND IS EXPECTED TO THE INTERSTATE 70 CORRIDOR AROUND DENVER BY 02Z
THIS EVENING...AND MUCH SOONER THAN THAT FOR THE LIMON AREA. WITH
COOLING TEMPS AND A LOWERING SUN ANGLE...THERE`S A BETTER FOR SNOW
ACCUMULATION ON THE PLAINS...AS WELL AS THE EAST FACE OF THE FRONT
RANGE DURING THIS PERIOD. HOWEVER ADDITIONAL SNOW AMOUNTS ON THE
FRONT RANGE AND SOUTH PARK WOULD NOT WARRANT HOLDING ONTO THE WINTER
STORM WARNING. A WINTER WEATHER ADVISORY WOULD SUFFICE. IT`LL STILL
RUN UNTIL 06Z TONIGHT. LASTLY ADDED FOG TO THE PLAINS AND FOOTHILLS
FORECAST FOR THE REMAINDER OF THE NIGHT. VSBYS ANYWHERE FROM A
QUARTER MILE TO 4 MILES THROUGH THE EVENING.

ON SATURDAY...MODELS SHOW THE UPPER LOW STILL IMPACTING NORTHEAST
COLORADO FOR MOST OF THE DAY. MOISTURE WRAPPING AROUND THE BACK SIDE
OF THIS LOW AND A COOL N-NWLY WIND SHOULD KEEP THE FCST AREA
UNSEASONABLY COOL AND UNSETTLED. QG VV FIELDS SHOW A LOBE OF MID-
LEVEL LIFT SWINGING DOWN FROM SERN WYOMING DURING THE MORNING LIKELY
RESULTING IN AN UPTURN IN PRECIPITATION COVERAGE ACROSS THE NERN
PLAINS AND NRN FRONT RANGE. LIGHT SNOW ACCUMULATIONS A POSSIBILITY.
LATER IN THE DAY...THE CWA GRADUALLY COMES UNDER THE INFLUENCE OF
DRIER AIR AND SUBSIDENCE AS THE UPPER LOW CONTINUES TO PULL AWAY.
THERE PRECIP CHANCES SHOULD LIKEWISE DECREASE FROM SOUTHWEST TO
NORTHEAST DURING THE AFTERNOON. TEMPERATURES NEXT 24 HOURS WELL
BELOW AVERAGE WITH HIGH TEMPS ON SATURDAY GENERALLY 3-6 DEG F WARMER
THAN THOSE TODAY.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 415 PM MDT FRI APR 29 2016

THERE WILL BE A BREAK BETWEEN SYSTEMS SATURDAY NIGHT AND SUNDAY
MORNING. HOWEVER IT WILL REMAIN CLOUDY WITH LOTS OF MOISTURE AND A
SHALLOW UNSTABLE LAYER NEAR THE GROUND...SO A LOW CHANCE OF LIGHT
SHOWERS OR DRIZZLE IS IN ORDER. THERE MAY BE WIDESPREAD DRIPPINESS
BUT NOT EXPECTING MUCH IN THE WAY OF ACCUMULATION. THERE WAS SOME
THOUGHT OF FREEZING DRIZZLE EARLIER...BUT IT APPEARS TEMPERATURES
WILL GENERALLY BE ABOVE FREEZING WITH WARM AND WET ROADS. IF THERE
WERE UPSLOPE WINDS I WOULD BE CONCERNED WITH A RIBBON OF
FOG/FREEZING DRIZZLE IN THE FOOTHILLS BUT IT LOOKS LIKE THIS WILL
NOT BE THE CASE.

THERE IS A LITTLE BETTER AGREEMENT AND DEFINITION OF A WAVE
PASSING OVER AND SOUTH OF US ON SUNDAY INTO MONDAY. THE BEST LIFT
SHOULD BE TO THE SOUTH...AND IS GENERALLY WEAK...BUT IT WILL BE
WORKING ON A PRETTY FAVORABLE ENVIRONMENT WITH PLENTY OF MOISTURE
AND A SHALLOW UNSTABLE LAYER. SO IT MAY NOT BE HARD TO GENERATE
WIDESPREAD LIGHT PRECIPITATION AGAIN. RAISED POPS FOR THIS
PERIOD...NOT READY TO COMMIT TO THE WIDESPREAD PRECIPITATION
EVERYWHERE YET. TEMPERATURES SHOULD BE A LITTLE WARMER THAN THEY
ARE NOW AND PRECIPITATION SHOULD BE LIGHTER...SO THERE SHOULD BE LESS
IMPACT THAN WHAT WE ARE SEEING TODAY. STILL PROBABLY SOME SNOW
THOUGH...AT LEAST ABOVE 5000 FEET. THERE ARE TIMING DIFFERENCES ON
THE CLEARING OF THIS SYSTEM ON MONDAY...TRENDS ARE TOWARD MOVING
THE HIGHER LEVEL LIFT OUT EARLY MONDAY BUT WITH LOW LEVEL MOISTURE
LINGERING MUCH OF THE DAY.

A RIDGE WILL BUILD OVER US FOR THE REST OF THE WEEK. A WRINKLE
THAT DEVELOPED IN LAST NIGHTS ECMWF IS PERSISTING TODAY...A LOW
THAT DEVELOPS OVER SASKATCHEWAN AND DROPS INTO THE WESTERN U.S.
IF THIS DOES OCCUR...AND IT IS A MINORITY OPINION...IT IS PROBABLY
NOT MUCH OF A WEATHER MAKER BUT COULD HOLD BACK THE WARMING AND
GENERATE SOME CLOUD COVER...MAINLY AFFECTING TUESDAY AND
WEDNESDAY. PRETTY WARM BY THE END OF THE WEEK...WE COULD BE BACK
NEAR 80. THERE IS INCREASING CONSENSUS ON A BIG LOW MOVING INTO
THE WEST FOR NEXT WEEKEND...SO WE COULD BE BACK TO COOL AND WET BY
SUNDAY. WAY TOO EARLY FOR ANY CONFIDENCE OR DETAILS YET...A
PACIFIC SYSTEM WOULD PROBABLY NOT BE REAL COLD...LIKELY WARMER
THAN THE CURRENT SYSTEM.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 415 PM MDT FRI APR 29 2016

ILS CIGS AND VSBYS AT DENVER AREA AIRPORTS THROUGH MID-
EVENING...THEN GRADUAL IMPROVEMENT WITH CIGS RISING ABOVE 3000 FT
AFTER MIDNIGHT. WINDS VARIABLE IN DIRECTION AT SPEEDS GENERALLY
UNDER 8 KTS. ON SATURDAY...SNOW CHANCES SHOULD INCREASE AGAIN IN
THE MORNING WITH A WEAK DISTURBANCE SWINGING DOWN FORM WYOMING.
COULD SEE LIGHT ACCUMULATION AND ILS CIGS AND DENVER AREA
AIRPORTS THROUGH 18Z. THEN GRADUAL IMPROVEMENT WITH RISING CIGS
AND VSBYS WITH DRIER AIR SPREADING DOWN FROM WYOMING ON NORTHERLY
WINDS.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR
COZ033>037-041.

&&

$$

SHORT TERM...BAKER
LONG TERM...GIMMESTAD
AVIATION...BAKER





000
FXUS65 KBOU 291723
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
1123 AM MDT FRI APR 29 2016

.UPDATE...
ISSUED AT 1120 AM MDT FRI APR 29 2016

MODIFICATIONS HAVE BEEN MADE TO SNOW AMOUNTS FOR TODAY AND
TONIGHT. BASICALLY...LOWERED AMOUNTS IN THE MTNS...ESPLY WEST OF
THE CONTINENTAL DIVIDE AND FOR THE FOOTHILLS...ESPLY NORTH OF
HIGHWAY 7. RAISED SNOW ACCUMS IN PARK COUNTY BASED ON RECENT
SPOTTER REPORT...AND ALSO RAISED SNOW AMTS ACRS THE SERN CORNER OF
THE CWA...IE ELBERT AND LINCOLN COUNTIES WHERE WX SPOTTERS AND
WX CAMS INDICATE 3-6 INCHES OF SNOW ON THE GROUND...CENTERED
AROUND LIMON AND HUGO. LASTLY...LOWERED SNOW AMOUNTS OVR NERN
PORTIONS OF THE I-25 CORRIDOR WHERE LITTLE TO NO SNOW HAS YET TO
PILE UP AND PCPN UP TO NOW HAS MAINLY BEEN RAIN OR DRIZZLE.

OVER THE NEXT SEVERAL HOURS...STILL ANTICIPATE A RAMP UP ON PRECIP
ACROSS NENR COLORADO WITH MEAN LAYER FLOW TURNING MORE EASTERLY AS
THE 500-400MB LOW CONTINUES TO TRACK EAST ALONG THE COLORADO/NEW
MEXICO BORDER. PINPOINTING SNOW AMOUNTS CONTINUE TO BE BIGGEST
CHALLENGE AS MODELS CONTINUE TO OFFER CONSIDERABLY DIFFER QPF
VALUES...ESPLY ON THE PLAINS. THE GFS BY FAR IS THE WETTEST OF
THE MODELS...AND IT HAS BEEN FOR THE PAST FEW DAYS. THE EC...SREF
AND HRRR QPF NUMBERS SEEM MORE REASONABLE BASED ON THE QG ASCENT...
INSTABILITY AND OROGRAPHIC LIFT PREDICTED BY THE MODEL BLEND.
THEREFORE WILL USE QPF ROUGHLY HALF OF THAT OFFERED BY THE GFS TO
REVISE SNOW AMOUNTS. LIQUID/SNOW RATIOS ON THE PLAINS BASED ON
FCST TEMPS IN THE 7.2 TO 9.4 TO 1 RANGE. HIGHER ELEVATIONS WHERE
TEMPS COLDER BY 4-8 DEGS...H2O TO SNOW RATIOS IN THE 12 TO 17 TO 1
RANGE.

NO CHANGES TO CURRENT WINTER WEATHER HIGHLIGHTS AT THIS TIME. IF
WE SEE MORE SNOW ACCUMULATION ON ROADWAYS ACRS ELBERT...LINCOLN
AND WASHINGTON COUNTIES...A WINTER WEATHER ADVISORY MAY BE
NECESSARY.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 306 AM MDT FRI APR 29 2016

WATER VAPOR IMAGERY SHOWING ELONGATED UPPER LOW FROM EASTERN UTAH
TO NORTHWEST NEW MEXICO. PRECIPITATION HAS BEEN SLOW TO DEVELOP
ESPECIALLY NORTHERN SECTIONS OF THE CWA. THERE HAS BEEN A GENERAL
NORTHWARD SPREAD OF THE PRECIP WITH MAINLY SNOW FROM DENVER
SOUTHWARD. FURTHER NORTH TEMPERATURES ARE A BIT HIGHER SO LIGHT
RAIN AND DRIZZLE CONTINUE TO FALL FROM BOULDER NORTHWARD. EVEN
WITH THE HEAVIER PRECIP SHOWN ON RADAR...OBSERVATIONS SITES AT
DENVER ARE ONLY SHOWING LIGHT SNOW. PART OF THE PROBLEM IS THE
LIGHT SOUTHEAST FLOW WHICH IS DOWNSLOPING OVER THE FRONT RANGE SO
ONLY A VERY WEAK UPSLOPE COMPONENT. WE ALSO HAVE E A STRONG
SOUTHERLY MID LEVEL FLOW WHICH ALSO MAY BE LIMITING PRECIP. EVEN
NOW THERE APPEARS TO BE DRYING OR DIMINISHMENT OF PRECIP OVER THE
PALMER DIVIDE. LATEST HRRR PICKS UP ON THIS SO A LULL IN THE
PRECIP EARLY THIS AM BEFORE BECOMING WIDESPREAD AGAIN BY LATER BY
LATER THIS MORNING.

AS FOR THE WINTER HILITES...AM CONCERNED THAT WILL NOT BE ABLE TO
MAKE SNOWFALL CRITERIA IN THE MOUNTAINS AND FOOTHILLS. HAVE
LOWERED AMOUNTS....AND TOTAL VALUES LOOK NOW TO BE AROUND 4 TO 9
INCHES ALONG EAST5 SLOPES AND 4 TO 6 INCHES OVER THE PALMER
DIVIDE. THERE JUST DOES NOT SEEM TO BE ENOUGH STRONG UPSLOPE FLOW
DUE TO THE ELONGATED UPPER LOW AND NOT A NICE COMPACT SYSTEM. FOR
NOW WILL LEAVE THE HILITES AS THE BEST POTENTIAL IS STILL TO COME
FOR THIS AFTERNOON. DAY SHIFT MAY DECIDE TO CANCEL HILITES IF
THINGS DON`T COME TOGETHER. OVERALL...HEAVIEST QPF AMOUNTS WILL BE
OVER THE EASTERN PLAINS OF COLORADO WITH LESSER AMOUNTS FURTHER
WEST.

THE UPPER LOW IS PROGGED TO CONSOLIDATE A BIT BETTER BY LATER
THIS AFTERNOON OVER SOUTHEAST COLORADO WHICH LOOKS TO SHOW THE
BEST POTENTIAL FOR PRECIP UNDER THE STRONGEST QG ASCENT.
TEMPERATURES WILL HOVER IN THE LOWER TO MID 30S TODAY AND GIVEN
HIGH SUN ANGLES...MOST OF THE SNOW WILL MELT ON PAVEMENT SURFACES
BUT STILL SOME LIGHT ACCUMULATIONS ON GRASSY SURFACE. LOOK FOR
GRADUAL IMPROVEMENT LATER THIS EVENING AND OVERNIGHT AS THE UPPER
LOW MOVES INTO CENTRAL KANSAS BY LATER TONIGHT. THERE WILL STILL
BE A FAIR AMOUNT OF WRAP AROUND PRECIP OVER FAR NORTHEAST PLAINS.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 306 AM MDT FRI APR 29 2016

ON SATURDAY...THE UPPER LOW WILL BE MOVING INTO SOUTHWESTERN
NEBRASKA WITH MOISTURE WRAPPING AROUND THE SYSTEM AND MOVING
ACROSS THE NORTHEAST PLAINS. HIGHEST POPS WILL BE NORTH AND EAST
OF DENVER...WITH THE BEST CHC OF ACCUMULATING SNOWFALL...ALBEIT
LIGHT...IN THE MORNING. AS THE SYSTEM CONTINUES TO TRACK TO THE
NORTHEAST SATURDAY AFTN/EVNG...THE MDLS SHOW WEAK DOWNWARD QG
OVER THE CWA. NAM12 SPATIAL CROSS SECTIONS MAINTAIN A WEAK ELY
FLOW BLO 700 MB SATURDAY NIGHT...BUT MUCH DRIER ALOFT. BEST CHC OF
PCPN WILL BE IN AND NEAR THE FRONT RANGE FOOTHILLS SATURDAY NIGHT
INTO SUNDAY MORNING. WITH THE DRIER AIR ALOFT...COULD SEE PATCHY
FREEZING DRIZZLE DEVELOP SO WILL THROW A LITTLE BIT OF THAT INTO
THE GRIDS. SUNDAY AFTERNOON INTO MONDAY MORNING...ANOTHER CLOSED
PACIFIC SYSTEM AROUND THE FOUR CORNERS REGION AT 18Z SUNDAY IS
PROGGED TO OPEN UP AND MOVE INTO NEBRASKA BY 18Z MONDAY. THIS
SYSTEM IS FAIRLY WEAK...BUT IT DOES HAVE SOME QG ASCENT IN THE MID
LEVELS AND DOES DEEPEN THE MOISTURE ALONG THE FRONT RANGE.
THEREFORE COULD SEE ANOTHER CHANCE OF PCPN...ESPECIALLY FROM THE
URBAN CORRIDOR WESTWARD. TEMPERATURES WILL MODIFY FURTHER ON
TUESDAY BUT AN INTERESTING FEATURE DOES SHOW UP ON THE ECMWF. A
LOW PRESSURE SYSTEM OVER SERN MT/WRN NORTH DAKOTA AROUND 18Z
MONDAY IS PROGGED SLIDE NORTHEAST TO SOUTHWEST AROUND AN OMEGA
RIDGE SITTING OVER THE NRN ROCKIES...AND INTO NWRN CO BY 18Z
TUESDAY. THIS COULD BRING A CHC OF PCPN TO THE REGION TUESDAY
AFTN/EVNG. THE GFS ON THE OTHER HAND SHOWS NO SUCH FEATURE...SO
MAINLY CHC POPS MAINLY OVER THE HIGHER TERRAIN AT THAT TIME. TREND
FOR DRIER AND WARMER STILL ON TRACK FOR THE REST OF THE WEEK WITH
AN UPPER LEVEL RIDGE THE PREVAILING FEATURE FOR WEDNESDAY AND
THURSDAY.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1120 AM MDT FRI APR 29 2016

ILS CIGS AND VSBYS ANTICIPATED AT DENVER AREA AIRPORTS THROUGH AT
LEAST 22Z THIS AFTERNOON. VSBY REDUCTIONS WILL BE A COMBINATION OF
SNOW AND FOG. WITH THE CORE OF THIS STORM SYSTEM PREDICTED TO
PASS TO OUR EAST AROUND MID-AFTERNOON TODAY...SHOULD SEE THE
MOIST UPSLOPE FLOW GRADUALLY WEAKENING AND BECOMING MORE
NORTHERLY IN DIRECTION. THIS SHOULD RESULT IN A REDUCTION IN
SNOWFALL RATES AND A SLIGHT IMPROVEMENT IN CIG HEIGHTS AND VSBYS
AT KBJC AND KDEN. NOT SO AT KAPA WHERE ILS CONDITIONS ARE LIKELY
TO PERSIST UNTIL AT LEAST 02Z-03Z THIS EVENING. SHOULD THEN SEE
GRADUAL IMPROVEMENT AT ALL DENVER AREA TERMINALS AFTER MIDNIGHT
WITH THIS STORM MOVING AWAY FROM THE FRONT RANGE.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR COZ041.

WINTER STORM WARNING UNTIL MIDNIGHT MDT TONIGHT FOR COZ033>037.

&&

$$

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





000
FXUS65 KBOU 291723
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
1123 AM MDT FRI APR 29 2016

.UPDATE...
ISSUED AT 1120 AM MDT FRI APR 29 2016

MODIFICATIONS HAVE BEEN MADE TO SNOW AMOUNTS FOR TODAY AND
TONIGHT. BASICALLY...LOWERED AMOUNTS IN THE MTNS...ESPLY WEST OF
THE CONTINENTAL DIVIDE AND FOR THE FOOTHILLS...ESPLY NORTH OF
HIGHWAY 7. RAISED SNOW ACCUMS IN PARK COUNTY BASED ON RECENT
SPOTTER REPORT...AND ALSO RAISED SNOW AMTS ACRS THE SERN CORNER OF
THE CWA...IE ELBERT AND LINCOLN COUNTIES WHERE WX SPOTTERS AND
WX CAMS INDICATE 3-6 INCHES OF SNOW ON THE GROUND...CENTERED
AROUND LIMON AND HUGO. LASTLY...LOWERED SNOW AMOUNTS OVR NERN
PORTIONS OF THE I-25 CORRIDOR WHERE LITTLE TO NO SNOW HAS YET TO
PILE UP AND PCPN UP TO NOW HAS MAINLY BEEN RAIN OR DRIZZLE.

OVER THE NEXT SEVERAL HOURS...STILL ANTICIPATE A RAMP UP ON PRECIP
ACROSS NENR COLORADO WITH MEAN LAYER FLOW TURNING MORE EASTERLY AS
THE 500-400MB LOW CONTINUES TO TRACK EAST ALONG THE COLORADO/NEW
MEXICO BORDER. PINPOINTING SNOW AMOUNTS CONTINUE TO BE BIGGEST
CHALLENGE AS MODELS CONTINUE TO OFFER CONSIDERABLY DIFFER QPF
VALUES...ESPLY ON THE PLAINS. THE GFS BY FAR IS THE WETTEST OF
THE MODELS...AND IT HAS BEEN FOR THE PAST FEW DAYS. THE EC...SREF
AND HRRR QPF NUMBERS SEEM MORE REASONABLE BASED ON THE QG ASCENT...
INSTABILITY AND OROGRAPHIC LIFT PREDICTED BY THE MODEL BLEND.
THEREFORE WILL USE QPF ROUGHLY HALF OF THAT OFFERED BY THE GFS TO
REVISE SNOW AMOUNTS. LIQUID/SNOW RATIOS ON THE PLAINS BASED ON
FCST TEMPS IN THE 7.2 TO 9.4 TO 1 RANGE. HIGHER ELEVATIONS WHERE
TEMPS COLDER BY 4-8 DEGS...H2O TO SNOW RATIOS IN THE 12 TO 17 TO 1
RANGE.

NO CHANGES TO CURRENT WINTER WEATHER HIGHLIGHTS AT THIS TIME. IF
WE SEE MORE SNOW ACCUMULATION ON ROADWAYS ACRS ELBERT...LINCOLN
AND WASHINGTON COUNTIES...A WINTER WEATHER ADVISORY MAY BE
NECESSARY.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 306 AM MDT FRI APR 29 2016

WATER VAPOR IMAGERY SHOWING ELONGATED UPPER LOW FROM EASTERN UTAH
TO NORTHWEST NEW MEXICO. PRECIPITATION HAS BEEN SLOW TO DEVELOP
ESPECIALLY NORTHERN SECTIONS OF THE CWA. THERE HAS BEEN A GENERAL
NORTHWARD SPREAD OF THE PRECIP WITH MAINLY SNOW FROM DENVER
SOUTHWARD. FURTHER NORTH TEMPERATURES ARE A BIT HIGHER SO LIGHT
RAIN AND DRIZZLE CONTINUE TO FALL FROM BOULDER NORTHWARD. EVEN
WITH THE HEAVIER PRECIP SHOWN ON RADAR...OBSERVATIONS SITES AT
DENVER ARE ONLY SHOWING LIGHT SNOW. PART OF THE PROBLEM IS THE
LIGHT SOUTHEAST FLOW WHICH IS DOWNSLOPING OVER THE FRONT RANGE SO
ONLY A VERY WEAK UPSLOPE COMPONENT. WE ALSO HAVE E A STRONG
SOUTHERLY MID LEVEL FLOW WHICH ALSO MAY BE LIMITING PRECIP. EVEN
NOW THERE APPEARS TO BE DRYING OR DIMINISHMENT OF PRECIP OVER THE
PALMER DIVIDE. LATEST HRRR PICKS UP ON THIS SO A LULL IN THE
PRECIP EARLY THIS AM BEFORE BECOMING WIDESPREAD AGAIN BY LATER BY
LATER THIS MORNING.

AS FOR THE WINTER HILITES...AM CONCERNED THAT WILL NOT BE ABLE TO
MAKE SNOWFALL CRITERIA IN THE MOUNTAINS AND FOOTHILLS. HAVE
LOWERED AMOUNTS....AND TOTAL VALUES LOOK NOW TO BE AROUND 4 TO 9
INCHES ALONG EAST5 SLOPES AND 4 TO 6 INCHES OVER THE PALMER
DIVIDE. THERE JUST DOES NOT SEEM TO BE ENOUGH STRONG UPSLOPE FLOW
DUE TO THE ELONGATED UPPER LOW AND NOT A NICE COMPACT SYSTEM. FOR
NOW WILL LEAVE THE HILITES AS THE BEST POTENTIAL IS STILL TO COME
FOR THIS AFTERNOON. DAY SHIFT MAY DECIDE TO CANCEL HILITES IF
THINGS DON`T COME TOGETHER. OVERALL...HEAVIEST QPF AMOUNTS WILL BE
OVER THE EASTERN PLAINS OF COLORADO WITH LESSER AMOUNTS FURTHER
WEST.

THE UPPER LOW IS PROGGED TO CONSOLIDATE A BIT BETTER BY LATER
THIS AFTERNOON OVER SOUTHEAST COLORADO WHICH LOOKS TO SHOW THE
BEST POTENTIAL FOR PRECIP UNDER THE STRONGEST QG ASCENT.
TEMPERATURES WILL HOVER IN THE LOWER TO MID 30S TODAY AND GIVEN
HIGH SUN ANGLES...MOST OF THE SNOW WILL MELT ON PAVEMENT SURFACES
BUT STILL SOME LIGHT ACCUMULATIONS ON GRASSY SURFACE. LOOK FOR
GRADUAL IMPROVEMENT LATER THIS EVENING AND OVERNIGHT AS THE UPPER
LOW MOVES INTO CENTRAL KANSAS BY LATER TONIGHT. THERE WILL STILL
BE A FAIR AMOUNT OF WRAP AROUND PRECIP OVER FAR NORTHEAST PLAINS.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 306 AM MDT FRI APR 29 2016

ON SATURDAY...THE UPPER LOW WILL BE MOVING INTO SOUTHWESTERN
NEBRASKA WITH MOISTURE WRAPPING AROUND THE SYSTEM AND MOVING
ACROSS THE NORTHEAST PLAINS. HIGHEST POPS WILL BE NORTH AND EAST
OF DENVER...WITH THE BEST CHC OF ACCUMULATING SNOWFALL...ALBEIT
LIGHT...IN THE MORNING. AS THE SYSTEM CONTINUES TO TRACK TO THE
NORTHEAST SATURDAY AFTN/EVNG...THE MDLS SHOW WEAK DOWNWARD QG
OVER THE CWA. NAM12 SPATIAL CROSS SECTIONS MAINTAIN A WEAK ELY
FLOW BLO 700 MB SATURDAY NIGHT...BUT MUCH DRIER ALOFT. BEST CHC OF
PCPN WILL BE IN AND NEAR THE FRONT RANGE FOOTHILLS SATURDAY NIGHT
INTO SUNDAY MORNING. WITH THE DRIER AIR ALOFT...COULD SEE PATCHY
FREEZING DRIZZLE DEVELOP SO WILL THROW A LITTLE BIT OF THAT INTO
THE GRIDS. SUNDAY AFTERNOON INTO MONDAY MORNING...ANOTHER CLOSED
PACIFIC SYSTEM AROUND THE FOUR CORNERS REGION AT 18Z SUNDAY IS
PROGGED TO OPEN UP AND MOVE INTO NEBRASKA BY 18Z MONDAY. THIS
SYSTEM IS FAIRLY WEAK...BUT IT DOES HAVE SOME QG ASCENT IN THE MID
LEVELS AND DOES DEEPEN THE MOISTURE ALONG THE FRONT RANGE.
THEREFORE COULD SEE ANOTHER CHANCE OF PCPN...ESPECIALLY FROM THE
URBAN CORRIDOR WESTWARD. TEMPERATURES WILL MODIFY FURTHER ON
TUESDAY BUT AN INTERESTING FEATURE DOES SHOW UP ON THE ECMWF. A
LOW PRESSURE SYSTEM OVER SERN MT/WRN NORTH DAKOTA AROUND 18Z
MONDAY IS PROGGED SLIDE NORTHEAST TO SOUTHWEST AROUND AN OMEGA
RIDGE SITTING OVER THE NRN ROCKIES...AND INTO NWRN CO BY 18Z
TUESDAY. THIS COULD BRING A CHC OF PCPN TO THE REGION TUESDAY
AFTN/EVNG. THE GFS ON THE OTHER HAND SHOWS NO SUCH FEATURE...SO
MAINLY CHC POPS MAINLY OVER THE HIGHER TERRAIN AT THAT TIME. TREND
FOR DRIER AND WARMER STILL ON TRACK FOR THE REST OF THE WEEK WITH
AN UPPER LEVEL RIDGE THE PREVAILING FEATURE FOR WEDNESDAY AND
THURSDAY.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1120 AM MDT FRI APR 29 2016

ILS CIGS AND VSBYS ANTICIPATED AT DENVER AREA AIRPORTS THROUGH AT
LEAST 22Z THIS AFTERNOON. VSBY REDUCTIONS WILL BE A COMBINATION OF
SNOW AND FOG. WITH THE CORE OF THIS STORM SYSTEM PREDICTED TO
PASS TO OUR EAST AROUND MID-AFTERNOON TODAY...SHOULD SEE THE
MOIST UPSLOPE FLOW GRADUALLY WEAKENING AND BECOMING MORE
NORTHERLY IN DIRECTION. THIS SHOULD RESULT IN A REDUCTION IN
SNOWFALL RATES AND A SLIGHT IMPROVEMENT IN CIG HEIGHTS AND VSBYS
AT KBJC AND KDEN. NOT SO AT KAPA WHERE ILS CONDITIONS ARE LIKELY
TO PERSIST UNTIL AT LEAST 02Z-03Z THIS EVENING. SHOULD THEN SEE
GRADUAL IMPROVEMENT AT ALL DENVER AREA TERMINALS AFTER MIDNIGHT
WITH THIS STORM MOVING AWAY FROM THE FRONT RANGE.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR COZ041.

WINTER STORM WARNING UNTIL MIDNIGHT MDT TONIGHT FOR COZ033>037.

&&

$$

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





000
FXUS65 KBOU 291005
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
405 AM MDT FRI APR 29 2016

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 306 AM MDT FRI APR 29 2016

WATER VAPOR IMAGERY SHOWING ELONGATED UPPER LOW FROM EASTERN UTAH
TO NORTHWEST NEW MEXICO. PRECIPITATION HAS BEEN SLOW TO DEVELOP
ESPECIALLY NORTHERN SECTIONS OF THE CWA. THERE HAS BEEN A GENERAL
NORTHWARD SPREAD OF THE PRECIP WITH MAINLY SNOW FROM DENVER
SOUTHWARD. FURTHER NORTH TEMPERATURES ARE A BIT HIGHER SO LIGHT
RAIN AND DRIZZLE CONTINUE TO FALL FROM BOULDER NORTHWARD. EVEN
WITH THE HEAVIER PRECIP SHOWN ON RADAR...OBSERVATIONS SITES AT
DENVER ARE ONLY SHOWING LIGHT SNOW. PART OF THE PROBLEM IS THE
LIGHT SOUTHEAST FLOW WHICH IS DOWNSLOPING OVER THE FRONT RANGE SO
ONLY A VERY WEAK UPSLOPE COMPONENT. WE ALSO HAVE E A STRONG
SOUTHERLY MID LEVEL FLOW WHICH ALSO MAY BE LIMITING PRECIP. EVEN
NOW THERE APPEARS TO BE DRYING OR DIMINISHMENT OF PRECIP OVER THE
PALMER DIVIDE. LATEST HRRR PICKS UP ON THIS SO A LULL IN THE
PRECIP EARLY THIS AM BEFORE BECOMING WIDESPREAD AGAIN BY LATER BY
LATER THIS MORNING.

AS FOR THE WINTER HILITES...AM CONCERNED THAT WILL NOT BE ABLE TO
MAKE SNOWFALL CRITERIA IN THE MOUNTAINS AND FOOTHILLS. HAVE
LOWERED AMOUNTS....AND TOTAL VALUES LOOK NOW TO BE AROUND 4 TO 9
INCHES ALONG EAST5 SLOPES AND 4 TO 6 INCHES OVER THE PALMER
DIVIDE. THERE JUST DOES NOT SEEM TO BE ENOUGH STRONG UPSLOPE FLOW
DUE TO THE ELONGATED UPPER LOW AND NOT A NICE COMPACT SYSTEM. FOR
NOW WILL LEAVE THE HILITES AS THE BEST POTENTIAL IS STILL TO COME
FOR THIS AFTERNOON. DAY SHIFT MAY DECIDE TO CANCEL HILITES IF
THINGS DON`T COME TOGETHER. OVERALL...HEAVIEST QPF AMOUNTS WILL BE
OVER THE EASTERN PLAINS OF COLORADO WITH LESSER AMOUNTS FURTHER
WEST.

THE UPPER LOW IS PROGGED TO CONSOLIDATE A BIT BETTER BY LATER
THIS AFTERNOON OVER SOUTHEAST COLORADO WHICH LOOKS TO SHOW THE
BEST POTENTIAL FOR PRECIP UNDER THE STRONGEST QG ASCENT.
TEMPERATURES WILL HOVER IN THE LOWER TO MID 30S TODAY AND GIVEN
HIGH SUN ANGLES...MOST OF THE SNOW WILL MELT ON PAVEMENT SURFACES
BUT STILL SOME LIGHT ACCUMULATIONS ON GRASSY SURFACE. LOOK FOR
GRADUAL IMPROVEMENT LATER THIS EVENING AND OVERNIGHT AS THE UPPER
LOW MOVES INTO CENTRAL KANSAS BY LATER TONIGHT. THERE WILL STILL
BE A FAIR AMOUNT OF WRAP AROUND PRECIP OVER FAR NORTHEAST PLAINS.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 306 AM MDT FRI APR 29 2016

ON SATURDAY...THE UPPER LOW WILL BE MOVING INTO SOUTHWESTERN
NEBRASKA WITH MOISTURE WRAPPING AROUND THE SYSTEM AND MOVING
ACROSS THE NORTHEAST PLAINS. HIGHEST POPS WILL BE NORTH AND EAST
OF DENVER...WITH THE BEST CHC OF ACCUMULATING SNOWFALL...ALBEIT
LIGHT...IN THE MORNING. AS THE SYSTEM CONTINUES TO TRACK TO THE
NORTHEAST SATURDAY AFTN/EVNG...THE MDLS SHOW WEAK DOWNWARD QG
OVER THE CWA. NAM12 SPATIAL CROSS SECTIONS MAINTAIN A WEAK ELY
FLOW BLO 700 MB SATURDAY NIGHT...BUT MUCH DRIER ALOFT. BEST CHC OF
PCPN WILL BE IN AND NEAR THE FRONT RANGE FOOTHILLS SATURDAY NIGHT
INTO SUNDAY MORNING. WITH THE DRIER AIR ALOFT...COULD SEE PATCHY
FREEZING DRIZZLE DEVELOP SO WILL THROW A LITTLE BIT OF THAT INTO
THE GRIDS. SUNDAY AFTERNOON INTO MONDAY MORNING...ANOTHER CLOSED
PACIFIC SYSTEM AROUND THE FOUR CORNERS REGION AT 18Z SUNDAY IS
PROGGED TO OPEN UP AND MOVE INTO NEBRASKA BY 18Z MONDAY. THIS
SYSTEM IS FAIRLY WEAK...BUT IT DOES HAVE SOME QG ASCENT IN THE MID
LEVELS AND DOES DEEPEN THE MOISTURE ALONG THE FRONT RANGE.
THEREFORE COULD SEE ANOTHER CHANCE OF PCPN...ESPECIALLY FROM THE
URBAN CORRIDOR WESTWARD. TEMPERATURES WILL MODIFY FURTHER ON
TUESDAY BUT AN INTERESTING FEATURE DOES SHOW UP ON THE ECMWF. A
LOW PRESSURE SYSTEM OVER SERN MT/WRN NORTH DAKOTA AROUND 18Z
MONDAY IS PROGGED SLIDE NORTHEAST TO SOUTHWEST AROUND AN OMEGA
RIDGE SITTING OVER THE NRN ROCKIES...AND INTO NWRN CO BY 18Z
TUESDAY. THIS COULD BRING A CHC OF PCPN TO THE REGION TUESDAY
AFTN/EVNG. THE GFS ON THE OTHER HAND SHOWS NO SUCH FEATURE...SO
MAINLY CHC POPS MAINLY OVER THE HIGHER TERRAIN AT THAT TIME. TREND
FOR DRIER AND WARMER STILL ON TRACK FOR THE REST OF THE WEEK WITH
AN UPPER LEVEL RIDGE THE PREVAILING FEATURE FOR WEDNESDAY AND
THURSDAY.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 306 AM MDT FRI APR 29 2016

LIGHT SNOW CONTINUES AT THE TERMINALS BUT COULD BE A LULL IN THE
SNOWFALL BETWEEN 11-14Z AS RADAR SHOWING SOME DRYING OVER THE
PALMER DIVIDE. MOST WIDESPREAD PRECIP WILL BE FROM LATER THIS AM
THROUGH THE AFTERNOON AS THE UPPER LOW APPROACHES SOUTHEAST
COLORADO. GRADUAL DIMINISHMENT IN PRECIP BY LATER THIS EVENING AND
OVERNIGHT.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR COZ041.

WINTER STORM WARNING UNTIL MIDNIGHT MDT TONIGHT FOR COZ033>037.

&&

$$

SHORT TERM...ENTREKIN
LONG TERM...COOPER
AVIATION...ENTREKIN





000
FXUS65 KBOU 290144
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
744 PM MDT THU APR 28 2016

.UPDATE...
ISSUED AT 744 PM MDT THU APR 28 2016

ALTHOUGH THE RADAR SHOWS SCATTERED SNOW SHOWERS MOVING OVER THE
MOUNTAINS AND A BAND OF RAIN SHOWERS MOVING NORTHWARD OVER EL PASO
AND LINCOLN COUNTIES...THE REST OF NORTHEAST COLORADO IS FREE OF
ANY PRECIPITATION AT THIS TIME. AREAS OF DRIZZLE STRETCH ALONG THE
FOOTHILLS...BUT THERE IS PRESENTLY NOTHING MORE THAN CLOUDY SKIES
TO THE EAST AND NORTHEAST OF DENVER. WILL UPDATE THE FORECAST
PACKAGE TO DELAY THE ONSET OF PRECIPITATION ACROSS NORTHEAST
COLORADO FOR A FEW MORE HOURS. THE REST OF THE FORECAST REMAINS ON
TRACK AS DYNAMIC FORCING WILL BE INCREASING ACROSS THE STATE
OVERNIGHT. FORECASTING THE PHASE OF THE PRECIPITATION ACROSS THE
PLAINS REMAINS A CHALLENGE DUE TO SURFACE TEMPERATURES EXPECTED TO
BE IN THE MID 30S MOST OF THE NIGHT. EVEN IF THE PRECIPITATION
CHANGES OVER TO SNOW...ONLY THE PALMER DIVIDE SHOULD SEE ANY
APPRECIABLE ACCUMULATIONS. DENVER...BOULDER AND FORT COLLINS MAY
WIND UP WITH ONLY SLUSHY ACCUMULATIONS. THE MORNING COMMUTE MAY
STILL HAVE PROBLEMS AS ONGOING SNOWFALL WILL LEAD TO QUITE A BIT
OF STANDING WATER ON ROADWAYS. WILL NOT MAKE ANY CHANGES TO THE
ONGOING SET OF HIGHLIGHTS.

&&

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 410 PM MDT THU APR 28 2016

CONFIDENCE IN THE FORECAST AND DETERMINISTIC MODELS LOW TO MODERATE
AT BEST LARGELY DUE TO THE UNCERTAINTY IN GUIDANCE TEMPERATURES...
SNOW ACCUMULATION DISTRIBUTION ON THE PLAINS AND PHASE CHANGE RATES.
THAT SAID...THE LARGE UPRIGHT UPPER TROUGH WITH ITS CLOSED LOW OVER
NORTH CENTRAL ARIZONA IS STILL FORECAST TO TRACK EAST ACROSS THE 4-
CORNERS REGION OVERNIGHT WITH THE 500MB SITTING OVER SWRN COLORADO
BY 12Z/FRIDAY ACCORDING TO A MODEL CONSENSUS. QG FIELDS SHOW A
STEADY INCREASE IN LARGE SCALE ASCENT AND INSTABILITY OVER THE
FORECAST AREA WITH AN INFLUX OF DEEP LAYER MOISTURE WITH SLY
DIVERGENT FLOW ALOFT. AT LOWER ELEVATIONS UPSLOPE GRADIENT ON THE
PLAINS WILL ALSO INCREASE OVERNIGHT...BUT MODELS NEVER REALLY
SHOW STRONG UPSLOPE INTO THE FRONT RANGE. FURTHERMORE PAST COUPLE
OF MODEL RUNS CONTINUE TO BACK OFF ON QPF AND SNOW ACCUM IN THE
MTNS AND FTHLS. EARLIER RUNS INDICATED 20-35 INCH STORM TOTAL AMTS
OVER THE EAST FACE OF THE FRONT RANGE. MODELS NOW SHOW OVERALL
SNOW TOTALS BY 00Z/SATURDAY UNDER 20 INCHES.

SHOULD SEE THE PRECIP SHIELD SPREADING NWRD ACRS THE FCST AREA
DURING THE NEXT SEVERAL HOURS...FIRST OVER THE HIGH COUNTRY. PRECIP
SHOULD BE ALL SNOW ABOVE 6500 FEET THROUGH EARLY THIS EVENING AND
RAIN/DRIZZLE...OR A RAIN/SNOW MIX ON THE PLAINS. ON THE PALMER
DIVIDE PRECIP IS EXPECTED TO START OUT AS A RAIN/SNOW MIX THIS
AFTERNOON AND CHANGE OVER TO SNOW BY EARLY TO MID-EVENING.

COMING UP WITH SNOW TOTALS AND PINNING DOWN WHERE THE RAIN/SNOW LINE
ARE COMMON CHALLENGES FOR SPRINGTIME STORMS. MODEL WETBULB ZERO
HEIGHTS AT THEIR HIGHEST THIS EVENING AND THEN GRADUALLY LOWER
THROUGH TOMORROW AFTERNOON WITH NLY FLOW ON THE BACK SIDE OF THE
EXITING TROUGH. IT/S NOT INCONCEIVABLE THAT FRONT RANGE MTNS AND
FTHLS COULD SEE A SIGNIFICANT FALL OFF IN SNOWFALL TOMORROW
AFTERNOON SHOULD NWLY/DOWNSLOPE FLOW SET UP. FOR NOW WILL HOLD ONTO
THE WINTER STORM WARNING FOR THESE AREAS UNTIL 06Z/SAT. WILL
ALSO HOLD ONTO THE WINTER WEATHER ADVISORY FOR THE PALMER DIVIDE
UNTIL 06Z/SATURDAY. WHILE 6-12 INCHES OF SNOW IS PREDICTED FOR
THIS ZONES...COULD SEE HALF OF IT MELT OFF DURING THE DAY FRIDAY.
SAME GOES FOR THE PLAINS. MUCH OF THE SNOW FALLING AT LOWER
ELEVATIONS SHOULD ALSO MELT AS IT FALLS WITH TEMPERATURES IN THE
MID30S FOR MUCH OF THE DAY AND DUE TO A HIGHER SUN ANGLE THIS TIME
OF YEAR. THE DENVER METRO AREA MAY END UP WITH A WINTER WEATHER
ADVISORY...NOT ONE WILL NOT BE ISSUED AT THIS TIME.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 410 PM MDT THU APR 28 2016

UPPER LOW WILL MOVE SLOWLY EASTWARD FRIDAY NIGHT AND SATURDAY WITH
A GRADUAL DECREASE IN ITS IMPACT. WRAPAROUND PRECIPITATION COMING
BACK INTO COLORADO...MODELS VARY IN HOW FAR SOUTH PRECIPITATION
COMES...AND IT WILL BE FIGHTING MODEST LOW LEVEL NORTHERLY FLOW
COMING DOWN THE CHEYENNE RIDGE. MORE SOUTHERLY SOLUTIONS HOLD ON
TO STEADY LIGHT PRECIPITATION AS FAR SOUTH AS INTERSTATE 70 INTO
SATURDAY MORNING...WHILE MORE NORTHERLY SOLUTIONS HOLD THIS OVER
THE CHEYENNE RIDGE WITH ONLY SPOTTY PRECIP FURTHER SOUTH BY THAT
TIME. THERE IS STILL WEAK FORCING AND PLENTY OF MOISTURE
AROUND...BUT AT SOME POINT THERE WILL BE ENOUGH DRYING TO STOP THE
STEADY LIGHT RAIN/SNOW. HOWEVER...ALSO STILL SOME LOW LEVEL
INSTABILITY SO THERE SHOULD STILL BE SOME SPOTTY LIGHT SHOWERS.
LITTLE CHANGE TO THE TEMPERATURES...STILL PROBABLY COLD ENOUGH FOR
SNOW AROUND DENVER BUT WARM ENOUGH FOR LIMITED IMPACT.

FOR SATURDAY NIGHT AND SUNDAY WE ARE BETWEEN THE LOW TO OUR EAST
AND A NEW LOW MOVING ACROSS THE SOUTHWEST. INITIALLY THERE IS NOT
MUCH GOING ON BUT STILL A MOIST ENVIRONMENT WITH SOME LOW POPS
STILL IN ORDER. BY SUNDAY AFTERNOON THERE SHOULD BE SOME WEAK LIFT
MOVING IN FROM THE SOUTHWEST. IT SHOULD BE FAIRLY WEAK BUT WORKING
ON A FAVORABLE ENVIRONMENT...STILL PLENTY OF MOISTURE AROUND AND
ONLY WEAK STABILITY. BUMPED UP POPS A LITTLE BIT FOR SUNDAY-MONDAY
TIME PERIOD BUT NOT EXPECTING THIS TO BE A SIGNIFICANT
PRECIPITATION EVENT. TEMPERATURES SHOULD BE THE SAME OR PROBABLY A
LITTLE WARMER.

WARMING TREND COMES TOWARD THE END OF THE WEEK...STILL A LITTLE
MOISTURE/INSTABILITY AROUND FOR SOME LOW POPS...MAINLY LIGHT
DIURNAL SHOWERS OVER THE MOUNTAINS. MODEL BLEND FORECAST IS FINE
FOR THIS TIME.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 744 PM MDT THU APR 28 2016

CEILINGS HAVE COME BACK DOWN TO LOW MVFR RANGE AS THE AIRMASS
REMAINS MOIST AND EASTERLY FLOW AT LOW LEVELS CONTINUES. A MIX OF
RAIN AND SNOW SHOULD DEVELOP OVER THE NEXT FEW HOURS AND THEN
CHANGE OVER TO SNOW BY MIDNIGHT. WITH TEMPERATURES IN THE MID 30S
MOST OF THE NIGHT...ACCUMULATIONS WILL BE HARD TO COME BY. AS
PRECIPITATION RATES INCREASE IN THE MORNING IT WILL BE POSSIBLE
FOR AN INCH OR TWO OF ACCUMULATION MAY DEVELOP. ADDITIONAL
ACCUMULATION WILL BE TOUGH THROUGH THE DAY TOMORROW...BUT CEILINGS
SHOULD BE IN THE IFR RANGE MOST OF THE DAY.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT FRIDAY NIGHT FOR
COZ041.

WINTER STORM WARNING UNTIL MIDNIGHT MDT FRIDAY NIGHT FOR
COZ033>037.

&&

$$

UPDATE...DANKERS
SHORT TERM...BAKER
LONG TERM...GIMMESTAD
AVIATION...DANKERS





000
FXUS65 KBOU 290144
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
744 PM MDT THU APR 28 2016

.UPDATE...
ISSUED AT 744 PM MDT THU APR 28 2016

ALTHOUGH THE RADAR SHOWS SCATTERED SNOW SHOWERS MOVING OVER THE
MOUNTAINS AND A BAND OF RAIN SHOWERS MOVING NORTHWARD OVER EL PASO
AND LINCOLN COUNTIES...THE REST OF NORTHEAST COLORADO IS FREE OF
ANY PRECIPITATION AT THIS TIME. AREAS OF DRIZZLE STRETCH ALONG THE
FOOTHILLS...BUT THERE IS PRESENTLY NOTHING MORE THAN CLOUDY SKIES
TO THE EAST AND NORTHEAST OF DENVER. WILL UPDATE THE FORECAST
PACKAGE TO DELAY THE ONSET OF PRECIPITATION ACROSS NORTHEAST
COLORADO FOR A FEW MORE HOURS. THE REST OF THE FORECAST REMAINS ON
TRACK AS DYNAMIC FORCING WILL BE INCREASING ACROSS THE STATE
OVERNIGHT. FORECASTING THE PHASE OF THE PRECIPITATION ACROSS THE
PLAINS REMAINS A CHALLENGE DUE TO SURFACE TEMPERATURES EXPECTED TO
BE IN THE MID 30S MOST OF THE NIGHT. EVEN IF THE PRECIPITATION
CHANGES OVER TO SNOW...ONLY THE PALMER DIVIDE SHOULD SEE ANY
APPRECIABLE ACCUMULATIONS. DENVER...BOULDER AND FORT COLLINS MAY
WIND UP WITH ONLY SLUSHY ACCUMULATIONS. THE MORNING COMMUTE MAY
STILL HAVE PROBLEMS AS ONGOING SNOWFALL WILL LEAD TO QUITE A BIT
OF STANDING WATER ON ROADWAYS. WILL NOT MAKE ANY CHANGES TO THE
ONGOING SET OF HIGHLIGHTS.

&&

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 410 PM MDT THU APR 28 2016

CONFIDENCE IN THE FORECAST AND DETERMINISTIC MODELS LOW TO MODERATE
AT BEST LARGELY DUE TO THE UNCERTAINTY IN GUIDANCE TEMPERATURES...
SNOW ACCUMULATION DISTRIBUTION ON THE PLAINS AND PHASE CHANGE RATES.
THAT SAID...THE LARGE UPRIGHT UPPER TROUGH WITH ITS CLOSED LOW OVER
NORTH CENTRAL ARIZONA IS STILL FORECAST TO TRACK EAST ACROSS THE 4-
CORNERS REGION OVERNIGHT WITH THE 500MB SITTING OVER SWRN COLORADO
BY 12Z/FRIDAY ACCORDING TO A MODEL CONSENSUS. QG FIELDS SHOW A
STEADY INCREASE IN LARGE SCALE ASCENT AND INSTABILITY OVER THE
FORECAST AREA WITH AN INFLUX OF DEEP LAYER MOISTURE WITH SLY
DIVERGENT FLOW ALOFT. AT LOWER ELEVATIONS UPSLOPE GRADIENT ON THE
PLAINS WILL ALSO INCREASE OVERNIGHT...BUT MODELS NEVER REALLY
SHOW STRONG UPSLOPE INTO THE FRONT RANGE. FURTHERMORE PAST COUPLE
OF MODEL RUNS CONTINUE TO BACK OFF ON QPF AND SNOW ACCUM IN THE
MTNS AND FTHLS. EARLIER RUNS INDICATED 20-35 INCH STORM TOTAL AMTS
OVER THE EAST FACE OF THE FRONT RANGE. MODELS NOW SHOW OVERALL
SNOW TOTALS BY 00Z/SATURDAY UNDER 20 INCHES.

SHOULD SEE THE PRECIP SHIELD SPREADING NWRD ACRS THE FCST AREA
DURING THE NEXT SEVERAL HOURS...FIRST OVER THE HIGH COUNTRY. PRECIP
SHOULD BE ALL SNOW ABOVE 6500 FEET THROUGH EARLY THIS EVENING AND
RAIN/DRIZZLE...OR A RAIN/SNOW MIX ON THE PLAINS. ON THE PALMER
DIVIDE PRECIP IS EXPECTED TO START OUT AS A RAIN/SNOW MIX THIS
AFTERNOON AND CHANGE OVER TO SNOW BY EARLY TO MID-EVENING.

COMING UP WITH SNOW TOTALS AND PINNING DOWN WHERE THE RAIN/SNOW LINE
ARE COMMON CHALLENGES FOR SPRINGTIME STORMS. MODEL WETBULB ZERO
HEIGHTS AT THEIR HIGHEST THIS EVENING AND THEN GRADUALLY LOWER
THROUGH TOMORROW AFTERNOON WITH NLY FLOW ON THE BACK SIDE OF THE
EXITING TROUGH. IT/S NOT INCONCEIVABLE THAT FRONT RANGE MTNS AND
FTHLS COULD SEE A SIGNIFICANT FALL OFF IN SNOWFALL TOMORROW
AFTERNOON SHOULD NWLY/DOWNSLOPE FLOW SET UP. FOR NOW WILL HOLD ONTO
THE WINTER STORM WARNING FOR THESE AREAS UNTIL 06Z/SAT. WILL
ALSO HOLD ONTO THE WINTER WEATHER ADVISORY FOR THE PALMER DIVIDE
UNTIL 06Z/SATURDAY. WHILE 6-12 INCHES OF SNOW IS PREDICTED FOR
THIS ZONES...COULD SEE HALF OF IT MELT OFF DURING THE DAY FRIDAY.
SAME GOES FOR THE PLAINS. MUCH OF THE SNOW FALLING AT LOWER
ELEVATIONS SHOULD ALSO MELT AS IT FALLS WITH TEMPERATURES IN THE
MID30S FOR MUCH OF THE DAY AND DUE TO A HIGHER SUN ANGLE THIS TIME
OF YEAR. THE DENVER METRO AREA MAY END UP WITH A WINTER WEATHER
ADVISORY...NOT ONE WILL NOT BE ISSUED AT THIS TIME.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 410 PM MDT THU APR 28 2016

UPPER LOW WILL MOVE SLOWLY EASTWARD FRIDAY NIGHT AND SATURDAY WITH
A GRADUAL DECREASE IN ITS IMPACT. WRAPAROUND PRECIPITATION COMING
BACK INTO COLORADO...MODELS VARY IN HOW FAR SOUTH PRECIPITATION
COMES...AND IT WILL BE FIGHTING MODEST LOW LEVEL NORTHERLY FLOW
COMING DOWN THE CHEYENNE RIDGE. MORE SOUTHERLY SOLUTIONS HOLD ON
TO STEADY LIGHT PRECIPITATION AS FAR SOUTH AS INTERSTATE 70 INTO
SATURDAY MORNING...WHILE MORE NORTHERLY SOLUTIONS HOLD THIS OVER
THE CHEYENNE RIDGE WITH ONLY SPOTTY PRECIP FURTHER SOUTH BY THAT
TIME. THERE IS STILL WEAK FORCING AND PLENTY OF MOISTURE
AROUND...BUT AT SOME POINT THERE WILL BE ENOUGH DRYING TO STOP THE
STEADY LIGHT RAIN/SNOW. HOWEVER...ALSO STILL SOME LOW LEVEL
INSTABILITY SO THERE SHOULD STILL BE SOME SPOTTY LIGHT SHOWERS.
LITTLE CHANGE TO THE TEMPERATURES...STILL PROBABLY COLD ENOUGH FOR
SNOW AROUND DENVER BUT WARM ENOUGH FOR LIMITED IMPACT.

FOR SATURDAY NIGHT AND SUNDAY WE ARE BETWEEN THE LOW TO OUR EAST
AND A NEW LOW MOVING ACROSS THE SOUTHWEST. INITIALLY THERE IS NOT
MUCH GOING ON BUT STILL A MOIST ENVIRONMENT WITH SOME LOW POPS
STILL IN ORDER. BY SUNDAY AFTERNOON THERE SHOULD BE SOME WEAK LIFT
MOVING IN FROM THE SOUTHWEST. IT SHOULD BE FAIRLY WEAK BUT WORKING
ON A FAVORABLE ENVIRONMENT...STILL PLENTY OF MOISTURE AROUND AND
ONLY WEAK STABILITY. BUMPED UP POPS A LITTLE BIT FOR SUNDAY-MONDAY
TIME PERIOD BUT NOT EXPECTING THIS TO BE A SIGNIFICANT
PRECIPITATION EVENT. TEMPERATURES SHOULD BE THE SAME OR PROBABLY A
LITTLE WARMER.

WARMING TREND COMES TOWARD THE END OF THE WEEK...STILL A LITTLE
MOISTURE/INSTABILITY AROUND FOR SOME LOW POPS...MAINLY LIGHT
DIURNAL SHOWERS OVER THE MOUNTAINS. MODEL BLEND FORECAST IS FINE
FOR THIS TIME.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 744 PM MDT THU APR 28 2016

CEILINGS HAVE COME BACK DOWN TO LOW MVFR RANGE AS THE AIRMASS
REMAINS MOIST AND EASTERLY FLOW AT LOW LEVELS CONTINUES. A MIX OF
RAIN AND SNOW SHOULD DEVELOP OVER THE NEXT FEW HOURS AND THEN
CHANGE OVER TO SNOW BY MIDNIGHT. WITH TEMPERATURES IN THE MID 30S
MOST OF THE NIGHT...ACCUMULATIONS WILL BE HARD TO COME BY. AS
PRECIPITATION RATES INCREASE IN THE MORNING IT WILL BE POSSIBLE
FOR AN INCH OR TWO OF ACCUMULATION MAY DEVELOP. ADDITIONAL
ACCUMULATION WILL BE TOUGH THROUGH THE DAY TOMORROW...BUT CEILINGS
SHOULD BE IN THE IFR RANGE MOST OF THE DAY.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT FRIDAY NIGHT FOR
COZ041.

WINTER STORM WARNING UNTIL MIDNIGHT MDT FRIDAY NIGHT FOR
COZ033>037.

&&

$$

UPDATE...DANKERS
SHORT TERM...BAKER
LONG TERM...GIMMESTAD
AVIATION...DANKERS





000
FXUS65 KBOU 282211
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
411 PM MDT THU APR 28 2016

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 410 PM MDT THU APR 28 2016

CONFIDENCE IN THE FORECAST AND DETERMINISTIC MODELS LOW TO MODERATE
AT BEST LARGELY DUE TO THE UNCERTAINTY IN GUIDANCE TEMPERATURES...
SNOW ACCUMULATION DISTRIBUTION ON THE PLAINS AND PHASE CHANGE RATES.
THAT SAID...THE LARGE UPRIGHT UPPER TROUGH WITH ITS CLOSED LOW OVER
NORTH CENTRAL ARIZONA IS STILL FORECAST TO TRACK EAST ACROSS THE 4-
CORNERS REGION OVERNIGHT WITH THE 500MB SITTING OVER SWRN COLORADO
BY 12Z/FRIDAY ACCORDING TO A MODEL CONSENSUS. QG FIELDS SHOW A
STEADY INCREASE IN LARGE SCALE ASCENT AND INSTABILITY OVER THE
FORECAST AREA WITH AN INFLUX OF DEEP LAYER MOISTURE WITH SLY
DIVERGENT FLOW ALOFT. AT LOWER ELEVATIONS UPSLOPE GRADIENT ON THE
PLAINS WILL ALSO INCREASE OVERNIGHT...BUT MODELS NEVER REALLY
SHOW STRONG UPSLOPE INTO THE FRONT RANGE. FURTHERMORE PAST COUPLE
OF MODEL RUNS CONTINUE TO BACK OFF ON QPF AND SNOW ACCUM IN THE
MTNS AND FTHLS. EARLIER RUNS INDICATED 20-35 INCH STORM TOTAL AMTS
OVER THE EAST FACE OF THE FRONT RANGE. MODELS NOW SHOW OVERALL
SNOW TOTALS BY 00Z/SATURDAY UNDER 20 INCHES.

SHOULD SEE THE PRECIP SHIELD SPREADING NWRD ACRS THE FCST AREA
DURING THE NEXT SEVERAL HOURS...FIRST OVER THE HIGH COUNTRY. PRECIP
SHOULD BE ALL SNOW ABOVE 6500 FEET THROUGH EARLY THIS EVENING AND
RAIN/DRIZZLE...OR A RAIN/SNOW MIX ON THE PLAINS. ON THE PALMER
DIVIDE PRECIP IS EXPECTED TO START OUT AS A RAIN/SNOW MIX THIS
AFTERNOON AND CHANGE OVER TO SNOW BY EARLY TO MID-EVENING.

COMING UP WITH SNOW TOTALS AND PINNING DOWN WHERE THE RAIN/SNOW LINE
ARE COMMON CHALLENGES FOR SPRINGTIME STORMS. MODEL WETBULB ZERO
HEIGHTS AT THEIR HIGHEST THIS EVENING AND THEN GRADUALLY LOWER
THROUGH TOMORROW AFTERNOON WITH NLY FLOW ON THE BACK SIDE OF THE
EXITING TROUGH. IT/S NOT INCONCEIVABLE THAT FRONT RANGE MTNS AND
FTHLS COULD SEE A SIGNIFICANT FALL OFF IN SNOWFALL TOMORROW
AFTERNOON SHOULD NWLY/DOWNSLOPE FLOW SET UP. FOR NOW WILL HOLD ONTO
THE WINTER STORM WARNING FOR THESE AREAS UNTIL 06Z/SAT. WILL
ALSO HOLD ONTO THE WINTER WEATHER ADVISORY FOR THE PALMER DIVIDE
UNTIL 06Z/SATURDAY. WHILE 6-12 INCHES OF SNOW IS PREDICTED FOR
THIS ZONES...COULD SEE HALF OF IT MELT OFF DURING THE DAY FRIDAY.
SAME GOES FOR THE PLAINS. MUCH OF THE SNOW FALLING AT LOWER
ELEVATIONS SHOULD ALSO MELT AS IT FALLS WITH TEMPERATURES IN THE
MID30S FOR MUCH OF THE DAY AND DUE TO A HIGHER SUN ANGLE THIS TIME
OF YEAR. THE DENVER METRO AREA MAY END UP WITH A WINTER WEATHER
ADVISORY...NOT ONE WILL NOT BE ISSUED AT THIS TIME.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 410 PM MDT THU APR 28 2016

UPPER LOW WILL MOVE SLOWLY EASTWARD FRIDAY NIGHT AND SATURDAY WITH
A GRADUAL DECREASE IN ITS IMPACT. WRAPAROUND PRECIPITATION COMING
BACK INTO COLORADO...MODELS VARY IN HOW FAR SOUTH PRECIPITATION
COMES...AND IT WILL BE FIGHTING MODEST LOW LEVEL NORTHERLY FLOW
COMING DOWN THE CHEYENNE RIDGE. MORE SOUTHERLY SOLUTIONS HOLD ON
TO STEADY LIGHT PRECIPITATION AS FAR SOUTH AS INTERSTATE 70 INTO
SATURDAY MORNING...WHILE MORE NORTHERLY SOLUTIONS HOLD THIS OVER
THE CHEYENNE RIDGE WITH ONLY SPOTTY PRECIP FURTHER SOUTH BY THAT
TIME. THERE IS STILL WEAK FORCING AND PLENTY OF MOISTURE
AROUND...BUT AT SOME POINT THERE WILL BE ENOUGH DRYING TO STOP THE
STEADY LIGHT RAIN/SNOW. HOWEVER...ALSO STILL SOME LOW LEVEL
INSTABILITY SO THERE SHOULD STILL BE SOME SPOTTY LIGHT SHOWERS.
LITTLE CHANGE TO THE TEMPERATURES...STILL PROBABLY COLD ENOUGH FOR
SNOW AROUND DENVER BUT WARM ENOUGH FOR LIMITED IMPACT.

FOR SATURDAY NIGHT AND SUNDAY WE ARE BETWEEN THE LOW TO OUR EAST
AND A NEW LOW MOVING ACROSS THE SOUTHWEST. INITIALLY THERE IS NOT
MUCH GOING ON BUT STILL A MOIST ENVIRONMENT WITH SOME LOW POPS
STILL IN ORDER. BY SUNDAY AFTERNOON THERE SHOULD BE SOME WEAK LIFT
MOVING IN FROM THE SOUTHWEST. IT SHOULD BE FAIRLY WEAK BUT WORKING
ON A FAVORABLE ENVIRONMENT...STILL PLENTY OF MOISTURE AROUND AND
ONLY WEAK STABILITY. BUMPED UP POPS A LITTLE BIT FOR SUNDAY-MONDAY
TIME PERIOD BUT NOT EXPECTING THIS TO BE A SIGNIFICANT
PRECIPITATION EVENT. TEMPERATURES SHOULD BE THE SAME OR PROBABLY A
LITTLE WARMER.

WARMING TREND COMES TOWARD THE END OF THE WEEK...STILL A LITTLE
MOISTURE/INSTABILITY AROUND FOR SOME LOW POPS...MAINLY LIGHT
DIURNAL SHOWERS OVER THE MOUNTAINS. MODEL BLEND FORECAST IS FINE
FOR THIS TIME.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 410 PM MDT THU APR 28 2016

ILS CIGS AND LATER THIS EVENING ILS VISIBILITIES WITH SNOWFALL
AND FOG. SNOWFALL LIGHT TO MODERATE OVERNIGHT...WITH THE HEAVIER
SNOWFALL RATES AFTER MIDNIGHT. COULD SEE 1-3 INCHES OF SNOW
ACCUMULATION MAINLY ON GRASSY SURFACES BY MORNING. ON FRIDAY...
PERIOD OF LIGHT TO MODERATE SNOW IN THE MORNING WITH N-NELY WINDS
OF 5-15 KTS...THEN LIGHTER SNOWFALL OR A MIX OF LIGHT RAIN AND
SNOW IN THE AFTERNOON WITH THIS STORM SYSTEM MOVING AWAY FROM THE
FRONT RANGE.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT FRIDAY NIGHT FOR
COZ041.

WINTER STORM WARNING UNTIL MIDNIGHT MDT FRIDAY NIGHT FOR
COZ033>037.

&&

$$

SHORT TERM...BAKER
LONG TERM...GIMMESTAD
AVIATION...BAKER





000
FXUS65 KBOU 281608
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
1008 AM MDT THU APR 28 2016

.UPDATE...
ISSUED AT 1005 AM MDT THU APR 28 2016

SNOW BAND PASSING OVER SRN/CNTRL PORTIONS OF THE CWA ATTM WAS
QUICKLY LIFTING NORTH ACCORDING TO RADAR AND SFC OBS. ALREADY
SEEING SRN EDGE OF THIS LIGHT TO MODERATE PRECIP REACHING SRN
DOUGLAS AND SWRN ELBERT COUNTIES. AT ITS PRESENT FORWARD
SPEED...SHOULD SEE FIRST WAVE OF PRECIP ON THE PLAINS MOVING OUT
OF THE DENVER METRO AREA IN THE NEXT 2 HOURS OR SO...AND
EVENTUALLY THROUGH THE NRN TIER OF THE CWA BY EARLY AFTERNOON.
AS NOTED IN EARLIER FCST DISCUSSION...SHOULD SEE A DROP OFF IN
PRECIP ON THE PLAINS MID TO LATE AFTERNOON AND MESOSCALE MODELS
ARE INDICATING...AND THEN A QUICK REGENERATION IN PRECIP INITIALLY
ALONGTHE FRONT RANGE FOOTHILLS AND PALMER DIVIDE EARLY THIS
EVENING. SNOW AT THE MOMENT IS EXPECTED TO CHANGE OVER TO A MIX OF
RAIN AND SNOW OR ALL SNOW ON THE PLAINS THIS AFTERNOON WITH
WARMING TEMPS. AS FOR THE HIGH COUNTRY....SHOWERY PRECIP EXPECTED
THROUGH THE DAY WITH RAIN AND SNOW IN THE MTN VALLEYS AND SNOW AT
HIGHER ELEVATIONS. IT MAY BECOME A MIX OF SNOW/RAIN AT ELEVATIONS
BELOW 9500 FT WITH WARM AIR ADVECTION  AHEAD OF THE UPPER TROUGH.
NOTE ADJUSTMENTS TO NEARLY ALL FCST FIELDS DURING 1ST PERIOD.



&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM MDT THU APR 28 2016

WATER VAPOR IMAGERY SHOWING THE BROAD UPPER LOW ACROSS SOUTHERN
CALIFORNIA AND WEST CENTRAL ARIZONA THIS MORNING. AHEAD OF THE
MAIN LOW... THERE IS AN INITIAL PIECE OF ENERGY THAT HAS MOVED
INTO WESTERN COLORADO WITH INCREASING MOISTURE AND SHOWERS.
EXPECT A GRADUAL INCREASE IN SHOWER ACTIVITY BY LATER THIS
MORNING AS MOST OF THE SHORT RANGE MODELS SHOWING SHOWERS
INCREASING IN THE 15Z- 18Z TIME RANGE OVER THE FRONT RANGE
FOOTHILLS AND URBAN CORRIDOR. TEMPERATURES WILL WARM ENOUGH THAT
MUCH OF THE PRECIP WILL BE IN THE FORM OF RAIN ON THE PLAINS AND A
MIX OF RAIN AND SNOW IN THE FOOTHILLS.

THE MAIN UPPER LOW WILL MOVE TO NEAR THE 4 CORNERS REGION BY THIS
EVENING WITH MODERATE QG ASCENT AHEAD OF THE LOW AND DEEPENING
UPSLOPE FLOW. PRECIP WILL BECOME WIDESPREAD OVER THE ENTIRE AREA
OVERNIGHT WHILE SHOULD SEE ENOUGH COLD AIR TO SEE RAIN MIXING AND
CHANGING TO SNOW BY MIDNIGHT OVER THE URBAN CORRIDOR AND OVERNIGHT
ACROSS THE PLAINS. THERE ARE SOME DIFFERENCES IN THE TEMPERATURE
STRUCTURE OF THE MODELS AS THE NAM IS SHOWING A SLIGHTLY COLDER
AIRMASS THAN THE GFS.

WILL UPGRADE THE CURRENT WINTER STORM WATCHES TO WINTER STORM
WARNINGS FOR THE MOUNTAINS AND FOOTHILLS WHILE ADDING A WINTER
STORM WATCH TO ZONE 41 ACROSS THE PALMER DIVIDE. STILL ENOUGH
UNCERTAINTY ON HOW MUCH SNOW WILL ACTUALLY FALL OVER THE PALMER
DIVIDE GIVEN THE COLDER TEMPERATURES AND HIGHER ELEVATIONS. STILL
ENOUGH POTENTIAL TO HAVE A WATCH THERE.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 313 AM MDT THU APR 28 2016

THE MDLS REMAIN CONSISTENT IN THE TIMING AND TRACK OF THE NEXT
STORM SYSTEM THROUGH SATURDAY. IT IS STILL PROGGED TO BE NEAR THE
FOUR CORNERS REGION FRIDAY MORNING THEN IS EXPECTED TO MOVE ACROSS
THE STATE THROUGH FRIDAY NIGHT AND INTO SOUTH CENTRAL NEBRASKA BY
SATURDAY. THE MDLS SHOW MODERATE QG ASCENT THROUGH FRIDAY EVENING
THEN IT WEAKENS AS THE SYSTEM SHIFTS FURTHER EAST. NAM12 FORECAST
SOUNDINGS AND SPATIAL CROSS SECTIONS SHOW MOIST ADIABATIC LAPSE
RATES WITH A FAIRLY DEEP ESELY UPSLOPE COMPONENT THROUGH THE DAY
ON FRIDAY. AS THE TROUGH SHIFTS TO THE EAST FRIDAY NIGHT INTO
SATURDAY THE FLOW ALOFT TRANSITIONS TO NWLY. OVERALL QPF FOR MOST
OF THE MDLS IS AROUND 1-1.5 INCHES WITH THE GFS THE OUTLIER WITH
TWICE THOSE AMOUNT. WILL SIDE WITH THE CONSENSUS VS THE GFS AS IT
STILL SHOWS SNOWFALL OF 20-30 INCHES ACROSS THE NORTHEAST
PLAINS...WHICH SEEMS TOO HIGH FOR THIS TIME OF YEAR EVEN IF IT
WERE TO GET COLD ENOUGH.  THE AIRMASS DOES APPEAR COLD ENOUGH FOR
SNOW WITH THE BEST WINDOW FOR ACCUMULATING SNOWFALL FRIDAY MORNING
AND FRIDAY EVENING...WHEN TEMPERATURES ARE AROUND FREEZING. DO NOT
EXPECT THE SNOWFALL TO ACCUMULATE AS MUCH IN THE AFTERNOON AS
TEMPERATURES CLIMB INTO THE MID 30S. NO HIGHLIGHTS FOR THE URBAN
CORRIDOR AT THIS TIME...BUT A WINTER WEATHER ADVISORY MAY BE
NECESSARY FOR FRIDAY/FRIDAY NIGHT. STILL LOTS OF QUESTIONS
REGARDING THE POSSIBLE SNOW AMOUNTS FOR THE PLAINS...BUT MIXED
PCPN WOULD LOWER SNOWFALL NUMBERS SIGNIFICANTLY. OVER THE
WEEKEND...STILL UNSETTLED WITH COLORADO CAUGHT BETWEEN THE EXITING
TROUGH OVER NEBRASKA WITH ANOTHER TROUGH MOVING INTO NORTHWEST
ARIZONA. WEAK DEFORMATION AREA OVER COLORADO SATURDAY NIGHT INTO
SUNDAY...WITH AT LEAST THE NAM12 SHOWING FAVORABLE NELY UPSLOPE IN
THE LOWER LEVELS. AS A RESULT THE POTENTIAL FOR SOME LIGHT SNOW
POSSIBLE IN AND NEAR THE FOOTHILLS/PALMER DIVIDE SATURDAY
NIGHT/SUNDAY MORNING. THE NEXT SYSTEM IS PROGGED TO LIFT FOR NORTH
THAN EAST SUNDAY INTO MONDAY BUT A MOIST SOUTHWESTERLY FLOW MAY
STILL BRING SOME LIGHT SNOW TO THE REGION INTO EARLY NEXT WEEK.
SHOULD SEE SOME IMPROVEMENT TUESDAY INTO WEDNESDAY AS A RIDGE
BUILDS OVER THE ROCKY MOUNTAIN REGION...WITH DRIER AND WARMER
WEATHER BY THE MIDDLE OF NEXT WEEK.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1005 AM MDT THU APR 28 2016

LIGHT TO MODERATE SNOW BAND ASSOCIATED WITH A SHORTWAVE TROUGH
LIFTING NORTH ACRS THE METRO AREA AT PRESENT TIME...SHOULD SHIFT
NORTH OF THE METRO AREA BY AROUND MIDDAY. UNTIL THEN SNOW AND FOG
WILL PRODUCE ILS CIGS AND VSBYS AT DENVER AREA AIRPORTS. POSSIBLE
AIRPORTS COULD PICK UP A QUICK INCH OF SLUSHY SNOW...MAINLY ON
GRASSY SURFACES. AFTER 18Z...SHOULD SEE IMPROVING CIGS AND VSBYS
WITH PARTIAL CLEARING IN THE WAKE OF THE DISTURBANCE. PRECIP MAY
SWITCH BACK TO RAIN OR A MIX OF RAIN/SNOW IN THE AFTERNOON. DO NOT
SEE ANY ADDITIONAL SNOW ACCUMULATION IN THE AFTERNOON.

TONIGHT/S FORECAST NO CHANGE. PARENT STORM SYSTEM WILL BEGIN
IMPACTING THE METRO AREA IN THE EVENING WITH A RETURN TO ILS
CONDITIONS AT ALL AIRPORTS BY MID TO LATE EVENING WITH A MOIST
EAST-NORTHEAST UPSLOPE FLOW.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM 6 PM MDT THIS EVENING THROUGH FRIDAY
EVENING FOR COZ041.

WINTER STORM WARNING FROM 6 PM THIS EVENING TO MIDNIGHT MDT
FRIDAY NIGHT FOR COZ033>037.

&&

$$

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





000
FXUS65 KBOU 281004
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
404 AM MDT THU APR 28 2016

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM MDT THU APR 28 2016

WATER VAPOR IMAGERY SHOWING THE BROAD UPPER LOW ACROSS SOUTHERN
CALIFORNIA AND WEST CENTRAL ARIZONA THIS MORNING. AHEAD OF THE
MAIN LOW... THERE IS AN INITIAL PIECE OF ENERGY THAT HAS MOVED
INTO WESTERN COLORADO WITH INCREASING MOISTURE AND SHOWERS.
EXPECT A GRADUAL INCREASE IN SHOWER ACTIVITY BY LATER THIS
MORNING AS MOST OF THE SHORT RANGE MODELS SHOWING SHOWERS
INCREASING IN THE 15Z- 18Z TIME RANGE OVER THE FRONT RANGE
FOOTHILLS AND URBAN CORRIDOR. TEMPERATURES WILL WARM ENOUGH THAT
MUCH OF THE PRECIP WILL BE IN THE FORM OF RAIN ON THE PLAINS AND A
MIX OF RAIN AND SNOW IN THE FOOTHILLS.

THE MAIN UPPER LOW WILL MOVE TO NEAR THE 4 CORNERS REGION BY THIS
EVENING WITH MODERATE QG ASCENT AHEAD OF THE LOW AND DEEPENING
UPSLOPE FLOW. PRECIP WILL BECOME WIDESPREAD OVER THE ENTIRE AREA
OVERNIGHT WHILE SHOULD SEE ENOUGH COLD AIR TO SEE RAIN MIXING AND
CHANGING TO SNOW BY MIDNIGHT OVER THE URBAN CORRIDOR AND OVERNIGHT
ACROSS THE PLAINS. THERE ARE SOME DIFFERENCES IN THE TEMPERATURE
STRUCTURE OF THE MODELS AS THE NAM IS SHOWING A SLIGHTLY COLDER
AIRMASS THAN THE GFS.

WILL UPGRADE THE CURRENT WINTER STORM WATCHES TO WINTER STORM
WARNINGS FOR THE MOUNTAINS AND FOOTHILLS WHILE ADDING A WINTER
STORM WATCH TO ZONE 41 ACROSS THE PALMER DIVIDE. STILL ENOUGH
UNCERTAINTY ON HOW MUCH SNOW WILL ACTUALLY FALL OVER THE PALMER
DIVIDE GIVEN THE COLDER TEMPERATURES AND HIGHER ELEVATIONS. STILL
ENOUGH POTENTIAL TO HAVE A WATCH THERE.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 313 AM MDT THU APR 28 2016

THE MDLS REMAIN CONSISTENT IN THE TIMING AND TRACK OF THE NEXT
STORM SYSTEM THROUGH SATURDAY. IT IS STILL PROGGED TO BE NEAR THE
FOUR CORNERS REGION FRIDAY MORNING THEN IS EXPECTED TO MOVE ACROSS
THE STATE THROUGH FRIDAY NIGHT AND INTO SOUTH CENTRAL NEBRASKA BY
SATURDAY. THE MDLS SHOW MODERATE QG ASCENT THROUGH FRIDAY EVENING
THEN IT WEAKENS AS THE SYSTEM SHIFTS FURTHER EAST. NAM12 FORECAST
SOUNDINGS AND SPATIAL CROSS SECTIONS SHOW MOIST ADIABATIC LAPSE
RATES WITH A FAIRLY DEEP ESELY UPSLOPE COMPONENT THROUGH THE DAY
ON FRIDAY. AS THE TROUGH SHIFTS TO THE EAST FRIDAY NIGHT INTO
SATURDAY THE FLOW ALOFT TRANSITIONS TO NWLY. OVERALL QPF FOR MOST
OF THE MDLS IS AROUND 1-1.5 INCHES WITH THE GFS THE OUTLIER WITH
TWICE THOSE AMOUNT. WILL SIDE WITH THE CONSENSUS VS THE GFS AS IT
STILL SHOWS SNOWFALL OF 20-30 INCHES ACROSS THE NORTHEAST
PLAINS...WHICH SEEMS TOO HIGH FOR THIS TIME OF YEAR EVEN IF IT
WERE TO GET COLD ENOUGH.  THE AIRMASS DOES APPEAR COLD ENOUGH FOR
SNOW WITH THE BEST WINDOW FOR ACCUMULATING SNOWFALL FRIDAY MORNING
AND FRIDAY EVENING...WHEN TEMPERATURES ARE AROUND FREEZING. DO NOT
EXPECT THE SNOWFALL TO ACCUMULATE AS MUCH IN THE AFTERNOON AS
TEMPERATURES CLIMB INTO THE MID 30S. NO HIGHLIGHTS FOR THE URBAN
CORRIDOR AT THIS TIME...BUT A WINTER WEATHER ADVISORY MAY BE
NECESSARY FOR FRIDAY/FRIDAY NIGHT. STILL LOTS OF QUESTIONS
REGARDING THE POSSIBLE SNOW AMOUNTS FOR THE PLAINS...BUT MIXED
PCPN WOULD LOWER SNOWFALL NUMBERS SIGNIFICANTLY. OVER THE
WEEKEND...STILL UNSETTLED WITH COLORADO CAUGHT BETWEEN THE EXITING
TROUGH OVER NEBRASKA WITH ANOTHER TROUGH MOVING INTO NORTHWEST
ARIZONA. WEAK DEFORMATION AREA OVER COLORADO SATURDAY NIGHT INTO
SUNDAY...WITH AT LEAST THE NAM12 SHOWING FAVORABLE NELY UPSLOPE IN
THE LOWER LEVELS. AS A RESULT THE POTENTIAL FOR SOME LIGHT SNOW
POSSIBLE IN AND NEAR THE FOOTHILLS/PALMER DIVIDE SATURDAY
NIGHT/SUNDAY MORNING. THE NEXT SYSTEM IS PROGGED TO LIFT FOR NORTH
THAN EAST SUNDAY INTO MONDAY BUT A MOIST SOUTHWESTERLY FLOW MAY
STILL BRING SOME LIGHT SNOW TO THE REGION INTO EARLY NEXT WEEK.
SHOULD SEE SOME IMPROVEMENT TUESDAY INTO WEDNESDAY AS A RIDGE
BUILDS OVER THE ROCKY MOUNTAIN REGION...WITH DRIER AND WARMER
WEATHER BY THE MIDDLE OF NEXT WEEK.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 404 AM MDT THU APR 28 2016

WIDESPREAD STRATUS DECK ACROSS THE FRONT RANGE WITH STILL SOME
VERY LIGHT SNOW/FLURRIES MAINLY AROUND APA AND POINTS SOUTH.
FLURRIES WILL BE ENDING CLOSE TO DAYBREAK. EXPECT INCREASING
SHOWER ACTIVITY LATER THIS MORNING AND CONTINUE THROUGH THIS
AFTERNOON WITH LOWER CEILINGS. THE MORE WIDESPREAD RAIN WILL
DEVELOP THIS EVENING AND OVERNIGHT WHILE TEMPS WILL BE COLD ENOUGH
TO TURN MOST OF THE RAIN TO SNOW BY LATE EVENING OR CLOSE TO
MIDNIGHT. EXPECT SOME LIGHT SNOW ACCUMULATIONS OF 1-3 INCHES BY
FRIDAY AM BUT RUNWAY SURFACES MAINLY WET/SLUSHY.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM THIS EVENING THROUGH FRIDAY EVENING FOR
COZ041.

WINTER STORM WARNING FROM 6 PM THIS EVENING TO MIDNIGHT MDT
FRIDAY NIGHT FOR COZ033>037.

&&

$$

SHORT TERM...ENTREKIN
LONG TERM...COOPER
AVIATION...ENTREKIN





000
FXUS65 KBOU 281004
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
404 AM MDT THU APR 28 2016

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM MDT THU APR 28 2016

WATER VAPOR IMAGERY SHOWING THE BROAD UPPER LOW ACROSS SOUTHERN
CALIFORNIA AND WEST CENTRAL ARIZONA THIS MORNING. AHEAD OF THE
MAIN LOW... THERE IS AN INITIAL PIECE OF ENERGY THAT HAS MOVED
INTO WESTERN COLORADO WITH INCREASING MOISTURE AND SHOWERS.
EXPECT A GRADUAL INCREASE IN SHOWER ACTIVITY BY LATER THIS
MORNING AS MOST OF THE SHORT RANGE MODELS SHOWING SHOWERS
INCREASING IN THE 15Z- 18Z TIME RANGE OVER THE FRONT RANGE
FOOTHILLS AND URBAN CORRIDOR. TEMPERATURES WILL WARM ENOUGH THAT
MUCH OF THE PRECIP WILL BE IN THE FORM OF RAIN ON THE PLAINS AND A
MIX OF RAIN AND SNOW IN THE FOOTHILLS.

THE MAIN UPPER LOW WILL MOVE TO NEAR THE 4 CORNERS REGION BY THIS
EVENING WITH MODERATE QG ASCENT AHEAD OF THE LOW AND DEEPENING
UPSLOPE FLOW. PRECIP WILL BECOME WIDESPREAD OVER THE ENTIRE AREA
OVERNIGHT WHILE SHOULD SEE ENOUGH COLD AIR TO SEE RAIN MIXING AND
CHANGING TO SNOW BY MIDNIGHT OVER THE URBAN CORRIDOR AND OVERNIGHT
ACROSS THE PLAINS. THERE ARE SOME DIFFERENCES IN THE TEMPERATURE
STRUCTURE OF THE MODELS AS THE NAM IS SHOWING A SLIGHTLY COLDER
AIRMASS THAN THE GFS.

WILL UPGRADE THE CURRENT WINTER STORM WATCHES TO WINTER STORM
WARNINGS FOR THE MOUNTAINS AND FOOTHILLS WHILE ADDING A WINTER
STORM WATCH TO ZONE 41 ACROSS THE PALMER DIVIDE. STILL ENOUGH
UNCERTAINTY ON HOW MUCH SNOW WILL ACTUALLY FALL OVER THE PALMER
DIVIDE GIVEN THE COLDER TEMPERATURES AND HIGHER ELEVATIONS. STILL
ENOUGH POTENTIAL TO HAVE A WATCH THERE.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 313 AM MDT THU APR 28 2016

THE MDLS REMAIN CONSISTENT IN THE TIMING AND TRACK OF THE NEXT
STORM SYSTEM THROUGH SATURDAY. IT IS STILL PROGGED TO BE NEAR THE
FOUR CORNERS REGION FRIDAY MORNING THEN IS EXPECTED TO MOVE ACROSS
THE STATE THROUGH FRIDAY NIGHT AND INTO SOUTH CENTRAL NEBRASKA BY
SATURDAY. THE MDLS SHOW MODERATE QG ASCENT THROUGH FRIDAY EVENING
THEN IT WEAKENS AS THE SYSTEM SHIFTS FURTHER EAST. NAM12 FORECAST
SOUNDINGS AND SPATIAL CROSS SECTIONS SHOW MOIST ADIABATIC LAPSE
RATES WITH A FAIRLY DEEP ESELY UPSLOPE COMPONENT THROUGH THE DAY
ON FRIDAY. AS THE TROUGH SHIFTS TO THE EAST FRIDAY NIGHT INTO
SATURDAY THE FLOW ALOFT TRANSITIONS TO NWLY. OVERALL QPF FOR MOST
OF THE MDLS IS AROUND 1-1.5 INCHES WITH THE GFS THE OUTLIER WITH
TWICE THOSE AMOUNT. WILL SIDE WITH THE CONSENSUS VS THE GFS AS IT
STILL SHOWS SNOWFALL OF 20-30 INCHES ACROSS THE NORTHEAST
PLAINS...WHICH SEEMS TOO HIGH FOR THIS TIME OF YEAR EVEN IF IT
WERE TO GET COLD ENOUGH.  THE AIRMASS DOES APPEAR COLD ENOUGH FOR
SNOW WITH THE BEST WINDOW FOR ACCUMULATING SNOWFALL FRIDAY MORNING
AND FRIDAY EVENING...WHEN TEMPERATURES ARE AROUND FREEZING. DO NOT
EXPECT THE SNOWFALL TO ACCUMULATE AS MUCH IN THE AFTERNOON AS
TEMPERATURES CLIMB INTO THE MID 30S. NO HIGHLIGHTS FOR THE URBAN
CORRIDOR AT THIS TIME...BUT A WINTER WEATHER ADVISORY MAY BE
NECESSARY FOR FRIDAY/FRIDAY NIGHT. STILL LOTS OF QUESTIONS
REGARDING THE POSSIBLE SNOW AMOUNTS FOR THE PLAINS...BUT MIXED
PCPN WOULD LOWER SNOWFALL NUMBERS SIGNIFICANTLY. OVER THE
WEEKEND...STILL UNSETTLED WITH COLORADO CAUGHT BETWEEN THE EXITING
TROUGH OVER NEBRASKA WITH ANOTHER TROUGH MOVING INTO NORTHWEST
ARIZONA. WEAK DEFORMATION AREA OVER COLORADO SATURDAY NIGHT INTO
SUNDAY...WITH AT LEAST THE NAM12 SHOWING FAVORABLE NELY UPSLOPE IN
THE LOWER LEVELS. AS A RESULT THE POTENTIAL FOR SOME LIGHT SNOW
POSSIBLE IN AND NEAR THE FOOTHILLS/PALMER DIVIDE SATURDAY
NIGHT/SUNDAY MORNING. THE NEXT SYSTEM IS PROGGED TO LIFT FOR NORTH
THAN EAST SUNDAY INTO MONDAY BUT A MOIST SOUTHWESTERLY FLOW MAY
STILL BRING SOME LIGHT SNOW TO THE REGION INTO EARLY NEXT WEEK.
SHOULD SEE SOME IMPROVEMENT TUESDAY INTO WEDNESDAY AS A RIDGE
BUILDS OVER THE ROCKY MOUNTAIN REGION...WITH DRIER AND WARMER
WEATHER BY THE MIDDLE OF NEXT WEEK.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 404 AM MDT THU APR 28 2016

WIDESPREAD STRATUS DECK ACROSS THE FRONT RANGE WITH STILL SOME
VERY LIGHT SNOW/FLURRIES MAINLY AROUND APA AND POINTS SOUTH.
FLURRIES WILL BE ENDING CLOSE TO DAYBREAK. EXPECT INCREASING
SHOWER ACTIVITY LATER THIS MORNING AND CONTINUE THROUGH THIS
AFTERNOON WITH LOWER CEILINGS. THE MORE WIDESPREAD RAIN WILL
DEVELOP THIS EVENING AND OVERNIGHT WHILE TEMPS WILL BE COLD ENOUGH
TO TURN MOST OF THE RAIN TO SNOW BY LATE EVENING OR CLOSE TO
MIDNIGHT. EXPECT SOME LIGHT SNOW ACCUMULATIONS OF 1-3 INCHES BY
FRIDAY AM BUT RUNWAY SURFACES MAINLY WET/SLUSHY.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM THIS EVENING THROUGH FRIDAY EVENING FOR
COZ041.

WINTER STORM WARNING FROM 6 PM THIS EVENING TO MIDNIGHT MDT
FRIDAY NIGHT FOR COZ033>037.

&&

$$

SHORT TERM...ENTREKIN
LONG TERM...COOPER
AVIATION...ENTREKIN





000
FXUS65 KBOU 280229
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
829 PM MDT WED APR 27 2016

.UPDATE...
ISSUED AT 828 PM MDT WED APR 27 2016

EVENING RUNS OF THE HRRR AND RAP MODELS HAVE BEEN SHOWING
PRECIPITATION SPREADING OVER THE PALMER DIVIDE AND URBAN CORRIDOR
THROUGH THE LATE NIGHT AND MORNING HOURS. PRECIPITATION SEEMS TO
BE THE RESULT OF PERSISTENT MOIST SOUTHEASTERLY FLOW AT LOW LEVELS
OVERNIGHT IN COMBINATION WITH COLORADO LYING UNDER THE LEFT EXIT
REGION OF THE UPPER JET...ASSOCIATED WITH THE APPROACHING UPPER
LOW THAT WILL AFFECT OUR WEATHER THROUGH THE END OF THE WEEK AND
INTO THE WEEKEND. WILL BE UPDATING THE FORECAST TO INCLUDE MORE
PRECIPITATION ON THE PLAINS THURSDAY MORNING. MORNING TEMPERATURES
AND THE PHASE OF PRECIPITATION WILL BE THE TRICKY THINGS TO
FORECAST. MORNING LOWS IN THE DENVER AREA ARE FORECAST TO BE
AROUND 33 DEGREES...CERTAINLY COLD ENOUGH FOR SNOW...BUT
PRECIPITATION INTENSITIES IN THE RAP AND HRRR ARE ONLY A COUPLE
HUNDREDTHS PER HOUR. (.01-.05 INCH/HR) THESE LIGHT INTENSITIES
SHOULD NOT LEAD TO ANY SNOW ACCUMULATION. THAT BEING SAID...THE
PALMER RIDGE COULD SEE SOME LIGHT ACCUMULATION DUE TO THE COOLER
TEMPERATURES AND HIGHER ELEVATION THAN DENVER. ONCE THE RAIN OR
SNOW BEGINS ALONG THE I-25 CORRIDOR TOMORROW MORNING...IT SHOULD
THEN CONTINUE THROUGH THE EVENING AS THE DYNAMIC FORCING FROM THE
APPROACHING STORM STRENGTHENS.

SINCE THE EVENING MODELS ARE JUST NOW STARTING TO ARRIVE...WILL
NOT MAKE ANY CHANGES TO THE WINTER STORM WATCH IN THE MOUNTAINS
AND FOOTHILLS AT THIS TIME.

&&

.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 355 PM MDT WED APR 27 2016

LOWER SPECIFIC HUMIDITY/PRECIPITABLE WATER AND A MID-LEVEL CAP
BENEATH A PASSING SHORTWAVE RIDGE PRETTY MUCH SQUELCHED SHOWER
FORMATION AND SUPPRESSED UPDRAFTS TODAY. THE ISOLATED SHOWERS
IN THE FCST WORKED OUT. THE GUSTY N-NWLY WINDS ALSO MATERIALIZED
ON THE PLAINS AND ON THE HIGH MTN RIDGES ON THE BACKSIDE OF THE
DEPARTING UPPER TROUGH.

OVERNIGHT...ATTENTION SHIFTS TO THE LARGE UPPER TROUGH WINDING UP
OVER THE DESERT SOUTHWEST/LOWER GREAT BASIN. IN ADVANCE OF THIS
SYSTEM...MODELS SHOW A DEEPENING SOUTHWESTERLY TRANSPORTING
HIGHER THETA-E AIR NORTHWARD UP INTO COLORADO AND BY LATE TONIGHT
COULD SEE SNOWFALL ON THE INCREASE OVER HIGHER ELEVATIONS ACRS
SWRN PORTIONS OF THE CWA. MEANWHILE...MODELS SHOW EAST-
SOUTHEASTERLY LOW-LEVEL FLOW ON THE PLAINS MOVING MOISTURE
WESTWARD UP ALONG THE PALMER DIVIDE AND BY LATE TONIGHT RESULTING
IN PATCHY TO AREAS OF FOG AS FAR NORTH AS ERN PORTIONS OF THE
DENVER METRO AREA. VSBYS GENERALLY IN THE 3-5 MILE RANGE.
HOWEVER...THIS SAME ELY FLOW IS PROJECTED TO PRODUCE NEAR
SATURATED CONDITIONS IN THE FRONT RANGE FOOTHILLS LATE TONIGHT
THRU MID-MORNING ON THURSDAY. SO ADDED AREAS OF FOG HERE WHERE
SOME VSBYS IN SOME AREAS COULD DROP TO BELOW A MILE AROUND
SUNRISE. LOWS TONIGHT ONLY SLIGHTLY WARMER THAN LAST NIGHT

ON THURSDAY...WITH THE UPPER TROUGH CLOSING IN...SHOW SEE SNOWFALL
COVERAGE EXPANDING NORTHWARD ACROSS THE HIGH COUNTRY AND OVER THE
FRONT RANGE FOOTHILLS. PRECIP MAY START OUT AS A RAIN/SNOW MIX IN
THE FOOTHILLS AND LOWER MTN VALLEYS BUT WITH TIME CHANGE OVER TO
ALL SNOW IN THE AFTERNOON WITH PRECIP BECOMING MORE CONVECTIVE IN
CHARACTER. ON THE PLAINS...NO PRECIP TO START OUT THE DAY AND BY
MID-MORNING THE FOG SHOULD DISSIPATE. BY AFTERNOON SHOWERS FORMING
OVER THE FRONT RANGE FOOTHILLS WITH ENHANCED UPSLOPE FLOW ARE
EXPECTED TO BEGIN SPREADING OUT ONTO THE PLAINS WITH SWLY
TRANSPORT WINDS. WILL SLOWLY FALLING TEMPERATURES...COULD SEE
PRECIP IN AREAS NEAR THE FOOTHILLS AND ON THE PALMER DIVIDE
CHANGING TO A MIX OF RAIN/SNOW. MAY EVEN SEE A STRAY T-STORM OR
TWO ON THE PALMER DIVIDE LATE. HIGH TEMPS TOMORROW PROGGED TO BE
GENERALLY 3-5 DEG F LOWER THAN THOSE OBSERVED TODAY.

.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 355 PM MDT WED APR 27 2016

PRETTY REMARKABLE AGREEMENT BETWEEN THE MODELS REGARDING THE
SYNOPTIC SCALE EVOLUTION/MOVEMENT OF THE UPPER LOW AND ATTENDANT
QG VERTICAL VELOCITY FIELDS THROUGHOUT THE DURATION OF THE
UPCOMING STORM. THE TRACK IS NOT NECESSARILY PERFECT FOR A MAJOR
STORM...A BIT TOO FAR NORTH...BUT ENOUGH ASCENT FOR A LONG ENOUGH
TIME TO GENERATE DECENT PRECIPITATION AMOUNTS ACROSS MUCH OF THE
CWA. SURFACE EVOLUTION IS ALSO DECENT...PERHAPS NOT PERFECT...WITH
THE LATEST ECMWF SUGGESTING A BIT LESS UPSLOPE THAN THE OTHER
MODELS DURING THE DAY FRIDAY. THE OTHER BIG CONCERN...LIKELY THE
MOST IMPORTANT...IS THE THERMODYNAMIC STRUCTURE OF THE AIRMASS.
LOTS OF DISCREPANCIES BETWIXT THE MODELS WITH THE ECMWF AND NAM
SUGGESTING MORE SNOW AT LOWER ELEVATIONS WHILST THE GFS IS QUITE
A BIT WARMER. LASTLY...THE GFS HAS ABOUT 3-4 TIMES THE QPF ACROSS
PARTS OF THE CWA COMPARED TO THE OTHER SIMULATIONS SO PLENTY OF
UNCERTAINTY STILL LINGERS IN THE DETAILS. FORECAST PRECIPITABLE
WATER NUMBERS ARE SUBSTANTIAL ENOUGH TO SUGGEST THAT 0.5 TO 1.0
INCH OF WATER IS NOT OUT OF THE QUESTION IN MOST AREAS BEFORE ALL
IS SAID AND DONE. WINTER STORM WATCH HAS ALREADY BEEN POSTED FOR
THE FOOTHILLS...SOUTH PARK AND MOST OF THE MOUNTAINS.

LATER ON DOWN THE LINE GENERAL TROUGHINESS REMAINS OVER THE
CENTRAL ROCKIES WITH BELOW NORMAL TEMPERATURES THROUGH THE EARLY
PART OF NEXT WEEK. WARMER DRIER CONDITIONS MAY RETURN BY MIDWEEK.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 828 PM MDT WED APR 27 2016

WITH PRECIPITATION NOW EXPECTED TO BEGIN ACROSS THE DENVER AREA
EARLIER IN THE MORNING...WILL BE ADDING SHOWERS TO THE TAFS AS
EARLY AS 08Z OR 09Z. WILL KEEP THE MENITON OF FOG AHEAD OF THE
ARRIVAL OF THE PRECIPITATION.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM THURSDAY EVENING THROUGH FRIDAY EVENING
FOR COZ033>037.

&&

$$

UPDATE...DANKERS
SHORT TERM...BAKER
LONG TERM...ET
AVIATION...DANKERS





000
FXUS65 KBOU 272200
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
400 PM MDT WED APR 27 2016

.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 355 PM MDT WED APR 27 2016

LOWER SPECIFIC HUMIDITY/PRECIPITABLE WATER AND A MID-LEVEL CAP
BENEATH A PASSING SHORTWAVE RIDGE PRETTY MUCH SQUELCHED SHOWER
FORMATION AND SUPPRESSED UPDRAFTS TODAY. THE ISOLATED SHOWERS
IN THE FCST WORKED OUT. THE GUSTY N-NWLY WINDS ALSO MATERIALIZED
ON THE PLAINS AND ON THE HIGH MTN RIDGES ON THE BACKSIDE OF THE
DEPARTING UPPER TROUGH.

OVERNIGHT...ATTENTION SHIFTS TO THE LARGE UPPER TROUGH WINDING UP
OVER THE DESERT SOUTHWEST/LOWER GREAT BASIN. IN ADVANCE OF THIS
SYSTEM...MODELS SHOW A DEEPENING SOUTHWESTERLY TRANSPORTING
HIGHER THETA-E AIR NORTHWARD UP INTO COLORADO AND BY LATE TONIGHT
COULD SEE SNOWFALL ON THE INCREASE OVER HIGHER ELEVATIONS ACRS
SWRN PORTIONS OF THE CWA. MEANWHILE...MODELS SHOW EAST-
SOUTHEASTERLY LOW-LEVEL FLOW ON THE PLAINS MOVING MOISTURE
WESTWARD UP ALONG THE PALMER DIVIDE AND BY LATE TONIGHT RESULTING
IN PATCHY TO AREAS OF FOG AS FAR NORTH AS ERN PORTIONS OF THE
DENVER METRO AREA. VSBYS GENERALLY IN THE 3-5 MILE RANGE.
HOWEVER...THIS SAME ELY FLOW IS PROJECTED TO PRODUCE NEAR
SATURATED CONDITIONS IN THE FRONT RANGE FOOTHILLS LATE TONIGHT
THRU MID-MORNING ON THURSDAY. SO ADDED AREAS OF FOG HERE WHERE
SOME VSBYS IN SOME AREAS COULD DROP TO BELOW A MILE AROUND
SUNRISE. LOWS TONIGHT ONLY SLIGHTLY WARMER THAN LAST NIGHT

ON THURSDAY...WITH THE UPPER TROUGH CLOSING IN...SHOW SEE SNOWFALL
COVERAGE EXPANDING NORTHWARD ACROSS THE HIGH COUNTRY AND OVER THE
FRONT RANGE FOOTHILLS. PRECIP MAY START OUT AS A RAIN/SNOW MIX IN
THE FOOTHILLS AND LOWER MTN VALLEYS BUT WITH TIME CHANGE OVER TO
ALL SNOW IN THE AFTERNOON WITH PRECIP BECOMING MORE CONVECTIVE IN
CHARACTER. ON THE PLAINS...NO PRECIP TO START OUT THE DAY AND BY
MID-MORNING THE FOG SHOULD DISSIPATE. BY AFTERNOON SHOWERS FORMING
OVER THE FRONT RANGE FOOTHILLS WITH ENHANCED UPSLOPE FLOW ARE
EXPECTED TO BEGIN SPREADING OUT ONTO THE PLAINS WITH SWLY
TRANSPORT WINDS. WILL SLOWLY FALLING TEMPERATURES...COULD SEE
PRECIP IN AREAS NEAR THE FOOTHILLS AND ON THE PALMER DIVIDE
CHANGING TO A MIX OF RAIN/SNOW. MAY EVEN SEE A STRAY T-STORM OR
TWO ON THE PALMER DIVIDE LATE. HIGH TEMPS TOMORROW PROGGED TO BE
GENERALLY 3-5 DEG F LOWER THAN THOSE OBSERVED TODAY.

.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 355 PM MDT WED APR 27 2016

PRETTY REMARKABLE AGREEMENT BETWEEN THE MODELS REGARDING THE
SYNOPTIC SCALE EVOLUTION/MOVEMENT OF THE UPPER LOW AND ATTENDANT
QG VERTICAL VELOCITY FIELDS THROUGHOUT THE DURATION OF THE
UPCOMING STORM. THE TRACK IS NOT NECESSARILY PERFECT FOR A MAJOR
STORM...A BIT TOO FAR NORTH...BUT ENOUGH ASCENT FOR A LONG ENOUGH
TIME TO GENERATE DECENT PRECIPITATION AMOUNTS ACROSS MUCH OF THE
CWA. SURFACE EVOLUTION IS ALSO DECENT...PERHAPS NOT PERFECT...WITH
THE LATEST ECMWF SUGGESTING A BIT LESS UPSLOPE THAN THE OTHER
MODELS DURING THE DAY FRIDAY. THE OTHER BIG CONCERN...LIKELY THE
MOST IMPORTANT...IS THE THERMODYNAMIC STRUCTURE OF THE AIRMASS.
LOTS OF DISCREPANCIES BETWIXT THE MODELS WITH THE ECMWF AND NAM
SUGGESTING MORE SNOW AT LOWER ELEVATIONS WHILST THE GFS IS QUITE
A BIT WARMER. LASTLY...THE GFS HAS ABOUT 3-4 TIMES THE QPF ACROSS
PARTS OF THE CWA COMPARED TO THE OTHER SIMULATIONS SO PLENTY OF
UNCERTAINTY STILL LINGERS IN THE DETAILS. FORECAST PRECIPITABLE
WATER NUMBERS ARE SUBSTANTIAL ENOUGH TO SUGGEST THAT 0.5 TO 1.0
INCH OF WATER IS NOT OUT OF THE QUESTION IN MOST AREAS BEFORE ALL
IS SAID AND DONE. WINTER STORM WATCH HAS ALREADY BEEN POSTED FOR
THE FOOTHILLS...SOUTH PARK AND MOST OF THE MOUNTAINS.

LATER ON DOWN THE LINE GENERAL TROUGHINESS REMAINS OVER THE
CENTRAL ROCKIES WITH BELOW NORMAL TEMPERATURES THROUGH THE EARLY
PART OF NEXT WEEK. WARMER DRIER CONDITIONS MAY RETURN BY MIDWEEK.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 355 PM MDT WED APR 27 2016

VFR CIGS AND VSBYS ANTICIPATED THROUGH 05Z TONIGHT...THEN MOST
AREAS SHOULD SEE CIGS LOWERING WITH A MOIST EAST-SOUTHEAST
UPSLOPE FLOW. SOUTHERN AND EASTERN SECTIONS OF THE DENVER METRO
AREA...INCLUDING KDEN AND KAPA MAY SEE PATCHY FOG FORMING AFTER
09Z TONIGHT...WITH VSBYS GENERALLY IN THE 3-5 MILE RANGE THROUGH
ABOUT 15Z. THEN DISSIPATING WITH LIGHT RAIN SHOWERS BEGINNING TO
MOVE OFF THE FOOTHILLS. DURING THE AFTERNOON THERE IS A CHANCE OF
RAIN SHOWERS AT ALL DENVER AREA AIRPORT AND A CHANCE THAT THESE
SHOWERS MAY CHANGE TO A RAIN/SNOW MIX AT KAPA AND KBJC AFTER 21Z
WITH MVFR CIGS.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM THURSDAY EVENING THROUGH FRIDAY EVENING
FOR COZ033>037.

&&

$$

SHORT TERM...BAKER
LONG TERM...ET
AVIATION...BAKER





000
FXUS65 KBOU 271629
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
1029 AM MDT WED APR 27 2016

.UPDATE...
ISSUED AT 1025 AM MDT WED APR 27 2016

DRIER LOW TO MID-LEVEL AIR ROUNDING THE BACKSIDE OF THE EXITING
UPPER LOW NOW SPINNING OVER ERN NEBRASKA HAS GENERATED A LONG
SWATH OF CLEAR/MOSTLY CLEAR SKIES ACRS NENR COLORADO THIS MORNING.
IN ADDITION...STRONG NWLY FLOW AROUND THE UPPER LOW CONTINUES TO
PRODUCE GUSTY N-NWLY WINDS ON THE PLAINS GENERALLY EAST OF THE
CHEYENNE-GREELEY-LIMON LINE. PEAK GUSTS HAVE BEEN IN THE 30-35KT
RANGE PAST COUPLE OF HRS. CLOSER INTO THE FRONT RANGE...LIGHT WINDS
WERE TURNING INTO THE TERRAIN WHICH HAS PROVIDED SUFFICIENT
OROGRAPHIC LIFT WITH SOLAR HEATING TO GENERATE THE BATCH OF LOW TO
MID-LEVEL CLOUDS OVER AND ALONG THE FRONT RANGE. NOT SEEING ANY
PRECIP FALLING FROM THEM ON RADAR...AT LEAST NOT YET WITH A STG
STABLE LAYER NEAR MTN TOP LEVEL. MEANWHILE...MOISTURE WRAPPING
INTO THE HIGH COUNTRY WITH THE SAME NWLY FLOW MENTIONED ABOVE
HAS KEPT A NEARLY SOLID BLANKET OF LOW TO MID-LEVEL CLOUD OVER
AREA ROUGHLY ALONG AND WEST OF THE CONT DIVIDE. HOWEVER WITH THE
RIDGE TOP SUBSIDENCE WITH THE PASSING MID-LEVEL SHORTWAVE RIDGE
ANY PRECIP...IE SNOWFALL SHOULD BE CONFINED TO THE HIGHER WEST-
NORTHWEST FACING SLOPES REST OF THE DAY WITH PERHAPS NO MORE THAN
AN INCH OR SO OF NEW ACCUMULATION. ON THE PLAINS...ISOLATED SHOWERS
TRACKING SEWRD OFF THE FRONT RANGE THIS AFTERNOON ARE NOT EXPECTED
TO PRODUCE MORE THAN A COUPLE HUNDREDTHS OF AN INCH OF RAIN...AND
MAINLY WEST OF I-25 AND OVER THE PALMER DIVIDE. OTHERWISE TODAY`S
FORECAST IS PRETTY MUCH UNCHANGED WITH NO BIG CHANGES TO WIND AND
TEMPERATURE GRIDS.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM MDT WED APR 27 2016

AREAS OF LIGHT SNOW WILL CONTINUE TO DISSIPATE THROUGH 5 AM WITH
LINGERING CLOUDS OVER THE FRONT RANGE. LITTLE OR NO ADDITIONAL
SNOWFALL ACCUMULATION IS EXPECTED. THE MAIN UPPER LOW CONTINUES
TO SPIN OVER WESTERN KANSAS AND WILL GRADUALLY LIFT INTO NEBRASKA
BY THIS EVENING. THIS WILL RESULT IN CONTINUED WRAP AROUND CLOUDS
AND STILL SOME SHOWERS OVER FAR NORTHEAST COLORADO THROUGH THIS
EVENING. THERE WILL BE SOME WEAK INSTABILITY OVER MOUNTAINS AND
ADJACENT PLAINS THIS AFTERNOON RESULTING IN ISOLATED LIGHT SHOWERS
THIS AFTERNOON/EARLY EVENING. TEMPERATURES WILL BE A BIT WARMER
TODAY WITH READINGS IN THE LOWER TO MID 50S OVER THE PLAINS.

WEAK AND TEMPORARY RIDGING ALOFT FOR THIS EVENING BEFORE AN
INCREASE IN MOISTURE AGAIN FROM THE WEST WITH THE NEXT STORM
SYSTEM. SOME WEAK QG ASCENT MOVES IN LATER TONIGHT INTO THE
MOUNTAINS FOR AN INCREASING THREAT FOR SNOW SHOWERS. ANY
SIGNIFICANT SNOWFALL WILL HOLD OFF UNTIL LATER THURSDAY.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 218 AM MDT WED APR 27 2016

THU AND THU NIGHT...THE NEXT SYSTEM OVER SOUTHERN NEVADA AT 12Z
THU IS PROGGED TO MOVE INTO NORTH CENTRAL AZ BY 00Z FRI AND INTO
THE FOUR CORNERS REGION BY 12Z FRI. WEAK QG ASCENT WILL DEVELOP
FROM THE SOUTHWEST ON THU...WITH A DIFFLUENT SOUTHWESTERLY FLOW
ALOFT OVER THE REGION THU. THE AIRMASS WILL CONTINUE TO MOISTEN UP
THROUGH THE DAY...WITH A LOW LEVEL E/SELY UPSLOPE FLOW IN THE
AFTN. IN THE MOUNTAINS...THE SNOW LEVEL WILL BE FAIRLY HIGH
INITIALLY...9500-10000 FT...SO SNOW OR A MIX OF RAIN/SNOW IN THE
AFTN WILL LIMIT ACCUMULATING SNOWFALL. THURSDAY NIGHT INTO
FRIDAY...COOLER TEMPERATURES WITH A DEEPER SELY FLOW DEVELOPING
TO AROUND 600 MB. MORE SIGNIFICANT ACCUMULATIONS WILL BE
POSSIBLE...ESPECIALLY IN ZONES 34 AND THE NORTH PART OF ZONE 37
THURSDAY NIGHT. BY LATE THURSDAY NIGHT...COULD SEE SNOW INCREASING
IN COVERAGE AND INTENSITY IN THE FOOTHILLS. ON FRIDAY...MDT QG
ASCENT PROGGED FOR THE CWA...AS THE TROUGH LIFT NORTHEAST INTO
CNTRL CO BY 00Z SAT. BEST PERIOD OF UPSLOPE/QG ASCENT WILL BE
LATE THU NIGHT AND FRI. CANNOT RULE OUT TSTMS ESPECIALLY IN THE
AFTN/EVNG PERIOD BUT OVERALL COVERAGE SHOULD BE ISOLATED. THE
UPSLOPE BREAKS DOWN FRI NIGHT AS THE TROUGH SHIFTS INTO SWRN
NB/NWRN KS BY 12Z SAT. THE MDLS ARE PRETTY CONSISTENT WITH ONE
ANOTHER REGARDING THE TIMING/TRACK OF THIS SYSTEM THROUGH 00Z
SAT...WITH SOME DISCREPANCIES CROPPING UP FRI NIGHT. THE NAM12 MDL
GENERATES UP TO 20 INCHES IN THE MOUNTAINS BY 12Z SATURDAY. PREFER
THE SNOWFALL/RAINFALL AMOUNTS GENERATED BY THE NAM/ECMWF AT THIS
TIME...AS THE GFS APPEARS WAY OVERDONE WITH UP TO 30 INCHES IN
COMPARISON. ACROSS THE NORTHEAST PLAINS...PRIMARILY RAIN SHOWERS
EXPECTED THROUGH FRIDAY EVENING...THEN A RAIN/SNOW MIX OVERNIGHT.
THE MDLS DO GENERATE SIGNIFICANT ACCUMULATIONS OUT ON THE PLAINS
AS WELL...6-12 INCHES FM THE NAM12 AND WITH ANYWHERE FM 2-40
INCHES FM THE GFS. HARD TO BUY THESE AMOUNTS SO LATE IN THE
MONTH...SO FOR NOW HAVE DISCOUNTED THE GFS SOLUTION ALTOGETHER AT
THIS TIME. THE NAM12 SOLUTION MORE REASONABLE BUT STILL LOOKS TOO
HIGH. MAIN CONCERN WILL BE THE PALMER DIVIDE WHICH SHOULD KICK
OVER TO SNOW THURSDAY NIGHT. WILL LIKELY NEED TO HOIST A WINTER
STORM WATCH FOR THE FRONT RANGE MOUNTAINS/FOOTHILLS AT SOME
POINT...BUT THIS IS STILL PRIMARILY THE FOURTH/FIFTH PERIODS AT
THIS POINT. THE PALMER DIVIDE SOUTH OF DENVER...MAY ALSO NEED SOME
SORT OF HIGHLIGHT AT SOME POINT AS WELL. FRIDAY NIGHT INTO
SATURDAY...THE FOCUS FOR PCPN WILL BE ALONG THE PALMER DIVIDE AS
THE LOW LEVEL WINDS BECOME NORTH/NORTHWESTERLY. SAT AFTN/SAT
NIGHT...SHOWERS SHOULD DECREASE WITH ONE SYSTEM EXITING TO THE
EAST WHILE ANOTHER STARTS TO DROP INTO SRN NV. SOUTHWESTERLY FLOW
OVER CO ON SUN...WITH A CLOSED LOW OVER NWRN AZ...THIS SYSTEM
LIFTS NORTH INTO UT BY 12Z MONDAY. NOT REALLY SURE WHERE THIS WILL
END UP AT THIS POINT...SO BASICALLY CHC POPS IN THE GRIDS SUN
NIGHT AND MONDAY. AS THE LOW LIFTS A BIT FURTHER NORTH ON
TUE...LESS PCPN COVERAGE BUT STILL UNSETTLED WITH AFTN/EVNG
SHOWERS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1025 AM MDT WED APR 27 2016

SCATTERED LOW CLOUDS THIS MORNING AT DENVER AREA AIRPORTS WITH
BASES IN THE 2000-3000 FT AGL LEVELS DUE TO A LIGHT NORTHEASTERLY
UPSLOPE FLOW. THIS LOW CLOUD COVER IS EXPECTED TO THIN OUT AND
EVEN DISSIPATE AROUND MIDDAY WITH A SHIFT TO A DRIER NORTHERLY
WINDS WHICH COULD GUST 20-30KT IN AREAS EAST OF THE I-25 FOR THE
1ST PART OF THE AFTERNOON. THEN LOOK FOR WINDS TO RETURN TO A
EAST-NORTHEAST UPSLOPE COMPONENT LATE THIS AFTERNOON WHICH WILL
ENHANCE CLOUD DEVELOPMENT OVER THE METRO AREA AND POSSIBLY RESULT
IN A FEW LIGHT RAIN SHOWERS. MOST OF THIS SHOWER ACTIVITY IS
EXPECTED TO END DURING THE EVENING HOURS WITH THE LOSS OF DAYTIME
HEATING.


&&

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

$$

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





000
FXUS65 KBOU 270953
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
353 AM MDT WED APR 27 2016

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM MDT WED APR 27 2016

AREAS OF LIGHT SNOW WILL CONTINUE TO DISSIPATE THROUGH 5 AM WITH
LINGERING CLOUDS OVER THE FRONT RANGE. LITTLE OR NO ADDITIONAL
SNOWFALL ACCUMULATION IS EXPECTED. THE MAIN UPPER LOW CONTINUES
TO SPIN OVER WESTERN KANSAS AND WILL GRADUALLY LIFT INTO NEBRASKA
BY THIS EVENING. THIS WILL RESULT IN CONTINUED WRAP AROUND CLOUDS
AND STILL SOME SHOWERS OVER FAR NORTHEAST COLORADO THROUGH THIS
EVENING. THERE WILL BE SOME WEAK INSTABILITY OVER MOUNTAINS AND
ADJACENT PLAINS THIS AFTERNOON RESULTING IN ISOLATED LIGHT SHOWERS
THIS AFTERNOON/EARLY EVENING. TEMPERATURES WILL BE A BIT WARMER
TODAY WITH READINGS IN THE LOWER TO MID 50S OVER THE PLAINS.

WEAK AND TEMPORARY RIDGING ALOFT FOR THIS EVENING BEFORE AN
INCREASE IN MOISTURE AGAIN FROM THE WEST WITH THE NEXT STORM
SYSTEM. SOME WEAK QG ASCENT MOVES IN LATER TONIGHT INTO THE
MOUNTAINS FOR AN INCREASING THREAT FOR SNOW SHOWERS. ANY
SIGNIFICANT SNOWFALL WILL HOLD OFF UNTIL LATER THURSDAY.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 218 AM MDT WED APR 27 2016

THU AND THU NIGHT...THE NEXT SYSTEM OVER SOUTHERN NEVADA AT 12Z
THU IS PROGGED TO MOVE INTO NORTH CENTRAL AZ BY 00Z FRI AND INTO
THE FOUR CORNERS REGION BY 12Z FRI. WEAK QG ASCENT WILL DEVELOP
FROM THE SOUTHWEST ON THU...WITH A DIFFLUENT SOUTHWESTERLY FLOW
ALOFT OVER THE REGION THU. THE AIRMASS WILL CONTINUE TO MOISTEN UP
THROUGH THE DAY...WITH A LOW LEVEL E/SELY UPSLOPE FLOW IN THE
AFTN. IN THE MOUNTAINS...THE SNOW LEVEL WILL BE FAIRLY HIGH
INITIALLY...9500-10000 FT...SO SNOW OR A MIX OF RAIN/SNOW IN THE
AFTN WILL LIMIT ACCUMULATING SNOWFALL. THURSDAY NIGHT INTO
FRIDAY...COOLER TEMPERATURES WITH A DEEPER SELY FLOW DEVELOPING
TO AROUND 600 MB. MORE SIGNIFICANT ACCUMULATIONS WILL BE
POSSIBLE...ESPECIALLY IN ZONES 34 AND THE NORTH PART OF ZONE 37
THURSDAY NIGHT. BY LATE THURSDAY NIGHT...COULD SEE SNOW INCREASING
IN COVERAGE AND INTENSITY IN THE FOOTHILLS. ON FRIDAY...MDT QG
ASCENT PROGGED FOR THE CWA...AS THE TROUGH LIFT NORTHEAST INTO
CNTRL CO BY 00Z SAT. BEST PERIOD OF UPSLOPE/QG ASCENT WILL BE
LATE THU NIGHT AND FRI. CANNOT RULE OUT TSTMS ESPECIALLY IN THE
AFTN/EVNG PERIOD BUT OVERALL COVERAGE SHOULD BE ISOLATED. THE
UPSLOPE BREAKS DOWN FRI NIGHT AS THE TROUGH SHIFTS INTO SWRN
NB/NWRN KS BY 12Z SAT. THE MDLS ARE PRETTY CONSISTENT WITH ONE
ANOTHER REGARDING THE TIMING/TRACK OF THIS SYSTEM THROUGH 00Z
SAT...WITH SOME DISCREPANCIES CROPPING UP FRI NIGHT. THE NAM12 MDL
GENERATES UP TO 20 INCHES IN THE MOUNTAINS BY 12Z SATURDAY. PREFER
THE SNOWFALL/RAINFALL AMOUNTS GENERATED BY THE NAM/ECMWF AT THIS
TIME...AS THE GFS APPEARS WAY OVERDONE WITH UP TO 30 INCHES IN
COMPARISON. ACROSS THE NORTHEAST PLAINS...PRIMARILY RAIN SHOWERS
EXPECTED THROUGH FRIDAY EVENING...THEN A RAIN/SNOW MIX OVERNIGHT.
THE MDLS DO GENERATE SIGNIFICANT ACCUMULATIONS OUT ON THE PLAINS
AS WELL...6-12 INCHES FM THE NAM12 AND WITH ANYWHERE FM 2-40
INCHES FM THE GFS. HARD TO BUY THESE AMOUNTS SO LATE IN THE
MONTH...SO FOR NOW HAVE DISCOUNTED THE GFS SOLUTION ALTOGETHER AT
THIS TIME. THE NAM12 SOLUTION MORE REASONABLE BUT STILL LOOKS TOO
HIGH. MAIN CONCERN WILL BE THE PALMER DIVIDE WHICH SHOULD KICK
OVER TO SNOW THURSDAY NIGHT. WILL LIKELY NEED TO HOIST A WINTER
STORM WATCH FOR THE FRONT RANGE MOUNTAINS/FOOTHILLS AT SOME
POINT...BUT THIS IS STILL PRIMARILY THE FOURTH/FIFTH PERIODS AT
THIS POINT. THE PALMER DIVIDE SOUTH OF DENVER...MAY ALSO NEED SOME
SORT OF HIGHLIGHT AT SOME POINT AS WELL. FRIDAY NIGHT INTO
SATURDAY...THE FOCUS FOR PCPN WILL BE ALONG THE PALMER DIVIDE AS
THE LOW LEVEL WINDS BECOME NORTH/NORTHWESTERLY. SAT AFTN/SAT
NIGHT...SHOWERS SHOULD DECREASE WITH ONE SYSTEM EXITING TO THE
EAST WHILE ANOTHER STARTS TO DROP INTO SRN NV. SOUTHWESTERLY FLOW
OVER CO ON SUN...WITH A CLOSED LOW OVER NWRN AZ...THIS SYSTEM
LIFTS NORTH INTO UT BY 12Z MONDAY. NOT REALLY SURE WHERE THIS WILL
END UP AT THIS POINT...SO BASICALLY CHC POPS IN THE GRIDS SUN
NIGHT AND MONDAY. AS THE LOW LIFTS A BIT FURTHER NORTH ON
TUE...LESS PCPN COVERAGE BUT STILL UNSETTLED WITH AFTN/EVNG
SHOWERS.


&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 350 AM MDT WED APR 27 2016

STILL A FAIR AMOUNT OF STRATUS OVER THE FRONT RANGE AND LOCAL
TERMINALS BUT EXPECTED TO GRADUALLY DISSIPATE THROUGH THE EARLY
MORNING HOURS. COULD SEE A FEW SHOWERS THIS AFTERNOON AND EVENING
BUT COVERAGE MORE ISOLATED SO WILL NOT INCLUDE IN UPCOMING TAF.
SURFACE WINDS WILL INCREASE FROM THE NORTH AND NORTHWEST LATER
THIS MORNING BEFORE SHIFTING NORTHEAST LATE IN THE DAY.

&&

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

$$

SHORT TERM...ENTREKIN
LONG TERM...COOPER
AVIATION...ENTREKIN





000
FXUS65 KBOU 270953
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
353 AM MDT WED APR 27 2016

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM MDT WED APR 27 2016

AREAS OF LIGHT SNOW WILL CONTINUE TO DISSIPATE THROUGH 5 AM WITH
LINGERING CLOUDS OVER THE FRONT RANGE. LITTLE OR NO ADDITIONAL
SNOWFALL ACCUMULATION IS EXPECTED. THE MAIN UPPER LOW CONTINUES
TO SPIN OVER WESTERN KANSAS AND WILL GRADUALLY LIFT INTO NEBRASKA
BY THIS EVENING. THIS WILL RESULT IN CONTINUED WRAP AROUND CLOUDS
AND STILL SOME SHOWERS OVER FAR NORTHEAST COLORADO THROUGH THIS
EVENING. THERE WILL BE SOME WEAK INSTABILITY OVER MOUNTAINS AND
ADJACENT PLAINS THIS AFTERNOON RESULTING IN ISOLATED LIGHT SHOWERS
THIS AFTERNOON/EARLY EVENING. TEMPERATURES WILL BE A BIT WARMER
TODAY WITH READINGS IN THE LOWER TO MID 50S OVER THE PLAINS.

WEAK AND TEMPORARY RIDGING ALOFT FOR THIS EVENING BEFORE AN
INCREASE IN MOISTURE AGAIN FROM THE WEST WITH THE NEXT STORM
SYSTEM. SOME WEAK QG ASCENT MOVES IN LATER TONIGHT INTO THE
MOUNTAINS FOR AN INCREASING THREAT FOR SNOW SHOWERS. ANY
SIGNIFICANT SNOWFALL WILL HOLD OFF UNTIL LATER THURSDAY.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 218 AM MDT WED APR 27 2016

THU AND THU NIGHT...THE NEXT SYSTEM OVER SOUTHERN NEVADA AT 12Z
THU IS PROGGED TO MOVE INTO NORTH CENTRAL AZ BY 00Z FRI AND INTO
THE FOUR CORNERS REGION BY 12Z FRI. WEAK QG ASCENT WILL DEVELOP
FROM THE SOUTHWEST ON THU...WITH A DIFFLUENT SOUTHWESTERLY FLOW
ALOFT OVER THE REGION THU. THE AIRMASS WILL CONTINUE TO MOISTEN UP
THROUGH THE DAY...WITH A LOW LEVEL E/SELY UPSLOPE FLOW IN THE
AFTN. IN THE MOUNTAINS...THE SNOW LEVEL WILL BE FAIRLY HIGH
INITIALLY...9500-10000 FT...SO SNOW OR A MIX OF RAIN/SNOW IN THE
AFTN WILL LIMIT ACCUMULATING SNOWFALL. THURSDAY NIGHT INTO
FRIDAY...COOLER TEMPERATURES WITH A DEEPER SELY FLOW DEVELOPING
TO AROUND 600 MB. MORE SIGNIFICANT ACCUMULATIONS WILL BE
POSSIBLE...ESPECIALLY IN ZONES 34 AND THE NORTH PART OF ZONE 37
THURSDAY NIGHT. BY LATE THURSDAY NIGHT...COULD SEE SNOW INCREASING
IN COVERAGE AND INTENSITY IN THE FOOTHILLS. ON FRIDAY...MDT QG
ASCENT PROGGED FOR THE CWA...AS THE TROUGH LIFT NORTHEAST INTO
CNTRL CO BY 00Z SAT. BEST PERIOD OF UPSLOPE/QG ASCENT WILL BE
LATE THU NIGHT AND FRI. CANNOT RULE OUT TSTMS ESPECIALLY IN THE
AFTN/EVNG PERIOD BUT OVERALL COVERAGE SHOULD BE ISOLATED. THE
UPSLOPE BREAKS DOWN FRI NIGHT AS THE TROUGH SHIFTS INTO SWRN
NB/NWRN KS BY 12Z SAT. THE MDLS ARE PRETTY CONSISTENT WITH ONE
ANOTHER REGARDING THE TIMING/TRACK OF THIS SYSTEM THROUGH 00Z
SAT...WITH SOME DISCREPANCIES CROPPING UP FRI NIGHT. THE NAM12 MDL
GENERATES UP TO 20 INCHES IN THE MOUNTAINS BY 12Z SATURDAY. PREFER
THE SNOWFALL/RAINFALL AMOUNTS GENERATED BY THE NAM/ECMWF AT THIS
TIME...AS THE GFS APPEARS WAY OVERDONE WITH UP TO 30 INCHES IN
COMPARISON. ACROSS THE NORTHEAST PLAINS...PRIMARILY RAIN SHOWERS
EXPECTED THROUGH FRIDAY EVENING...THEN A RAIN/SNOW MIX OVERNIGHT.
THE MDLS DO GENERATE SIGNIFICANT ACCUMULATIONS OUT ON THE PLAINS
AS WELL...6-12 INCHES FM THE NAM12 AND WITH ANYWHERE FM 2-40
INCHES FM THE GFS. HARD TO BUY THESE AMOUNTS SO LATE IN THE
MONTH...SO FOR NOW HAVE DISCOUNTED THE GFS SOLUTION ALTOGETHER AT
THIS TIME. THE NAM12 SOLUTION MORE REASONABLE BUT STILL LOOKS TOO
HIGH. MAIN CONCERN WILL BE THE PALMER DIVIDE WHICH SHOULD KICK
OVER TO SNOW THURSDAY NIGHT. WILL LIKELY NEED TO HOIST A WINTER
STORM WATCH FOR THE FRONT RANGE MOUNTAINS/FOOTHILLS AT SOME
POINT...BUT THIS IS STILL PRIMARILY THE FOURTH/FIFTH PERIODS AT
THIS POINT. THE PALMER DIVIDE SOUTH OF DENVER...MAY ALSO NEED SOME
SORT OF HIGHLIGHT AT SOME POINT AS WELL. FRIDAY NIGHT INTO
SATURDAY...THE FOCUS FOR PCPN WILL BE ALONG THE PALMER DIVIDE AS
THE LOW LEVEL WINDS BECOME NORTH/NORTHWESTERLY. SAT AFTN/SAT
NIGHT...SHOWERS SHOULD DECREASE WITH ONE SYSTEM EXITING TO THE
EAST WHILE ANOTHER STARTS TO DROP INTO SRN NV. SOUTHWESTERLY FLOW
OVER CO ON SUN...WITH A CLOSED LOW OVER NWRN AZ...THIS SYSTEM
LIFTS NORTH INTO UT BY 12Z MONDAY. NOT REALLY SURE WHERE THIS WILL
END UP AT THIS POINT...SO BASICALLY CHC POPS IN THE GRIDS SUN
NIGHT AND MONDAY. AS THE LOW LIFTS A BIT FURTHER NORTH ON
TUE...LESS PCPN COVERAGE BUT STILL UNSETTLED WITH AFTN/EVNG
SHOWERS.


&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 350 AM MDT WED APR 27 2016

STILL A FAIR AMOUNT OF STRATUS OVER THE FRONT RANGE AND LOCAL
TERMINALS BUT EXPECTED TO GRADUALLY DISSIPATE THROUGH THE EARLY
MORNING HOURS. COULD SEE A FEW SHOWERS THIS AFTERNOON AND EVENING
BUT COVERAGE MORE ISOLATED SO WILL NOT INCLUDE IN UPCOMING TAF.
SURFACE WINDS WILL INCREASE FROM THE NORTH AND NORTHWEST LATER
THIS MORNING BEFORE SHIFTING NORTHEAST LATE IN THE DAY.

&&

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

$$

SHORT TERM...ENTREKIN
LONG TERM...COOPER
AVIATION...ENTREKIN





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