Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS65 KBOU 011014
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
414 AM MDT WED OCT 1 2014

.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 400 AM MDT WED OCT 1 2014

FALLING HEIGHTS OVER UTAH AT THE PRESENT TIME ON THE CYCLONIC
SIDE OF A 100+ KT JET AND IN VICINITY OF A SFC COLD FRONT. BOTH
ARE FORECAST TO SHIFT EAST ACRS COLORADO TODAY. TEMPERATURES ON
THE LEADING EDGE OF THIS SYSTEM WARM ENOUGH TO KEEP SNOW LEVELS AT
OR JUST ABOVE TIMBERLINE EARLY THIS MORNING. ONCE THE MILD
SOUTHWESTERLY FLOW AHEAD OF THIS WAVE TURNS WESTERLY SOMETIME
AROUND MIDDAY...SHOULD SEE THE SNOW LEVEL LOWER. LOCAL OROGRAPHIC
SNOW MODEL USING QG VV...TEMP...RH...WIND AND LAPSE RATE INPUT
FROM THE RUC...NAM AND GFS INDICATE STORM TOTAL SNOW AMOUNTS BY
MIDNIGHT TONIGHT ON THE ORDER OF 4-7 INCHES ABOVE 10K FT...WITH
LESSER AMTS DOWN TO AROUND 8500 FEET. LAPSE RATES STEEP ENOUGH FOR
AT LEAST ISOLATED T-STORMS BOTH IN THE MTNS AND ON THE PLAINS
TODAY. COULD SEE BURSTS OF MODERATE TO HEAVY SNOWFALL IN THE HIGH
COUNTRY WITH THIS CONVECTION THIS AFTERNOON AND EARLY EVENING. A
WINTER WEATHER ADVISORY FOR SNOW HAS BEEN ISSUED FOR NORTH CENTRAL
COLORADO MTN ZONES 31...33 AND 34 FOR THE PD 12 PM MDT TODAY TO 12
AM MDT TONIGHT. BASED ON LATEST MODEL DATA...SHOULD SEE QUICK
DROP OFF IN HIGH COUNTRY SNOWFALL NOT TOO LONG AFTER MIDNIGHT
WITH STRONG SUBSIDENCE AND MID-LEVEL DRYING MOVING OVER THE REGION
BEHIND THE EXITING SHORTWAVE TROUGH.

AT LOWER ELEVATIONS...MODELS SHOW A WEAK RATHER DISORGANIZED COLD
FRONT SIDING SOUTH ACROSS THE NERN COLORADO PLAINS MID TO LATE
MORNING...CAUSING A SHIFT TO NELY SFC WINDS. A SECOND SOMEWHAT
STRONGER SURGE OF COOLER AIR IS PROGGED TO BACK IN THIS AFTERNOON
PROVIDING ADDITIONAL LOW-LEVEL MOISTURE...COOLER AIR AND
OROGRAPHIC LIFT FOR SHOWER DEVELOPMENT OVER AND ALONG THE FRONT
RANGE AND PALMER DIVIDE. WENT WITH LIKELY POPS IN THESE AREAS WITH
RAIN AMOUNTS IN THE 0.15 TO 0.50 POSSIBLE BY THIS EVENING.
TEMPERATURES REMAIN TOO WARM FOR ANY SNOW ON THE PLAINS. HOWEVER
HIGHER PORTIONS OF THE PALMER DIVIDE AND UP ALONG THE CHEYENNE
RIDGE COULD SEE A MIX OF RAIN AND SNOW THIS EVENING BEFORE PRECIP
SHUTS OFF AFTER MIDNIGHT. EXCEPT FOR LOW CLOUDS LINGERING ALONG
THE EASTERN FRINGE OF THE FCST AREA AND OVER THE HIGHER WINDWARD
MTN SLOPES...SKIES SHOULD BEGIN CLEARING BEFORE MORNING WITH
STRONG SUBSIDENCE MOVING OVER THE AREA.


.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 400 AM MDT WED OCT 1 2014

AS HIGH AMPLITUDE RIDGING DEVELOPS ALONG WEST COAST...ONE LAST
UPPER WAVE WILL SWEEP ACROSS THE NORTHERN HIGH PLAINS ON THURSDAY
NIGHT. AN ASSOCIATED COLD FRONT WILL MOVE SOUTHWARD ACROSS
NORTHEAST COLORADO THURSDAY NIGHT WITH INCREASING NORTHEAST LOW
LEVEL FLOW. THERE IS ALSO A STRONG 120KT JET WHICH WILL NOSE INTO
FAR NE COLORADO DURING THIS PERIOD. MAIN CHANGE TO CURRENT
FORECAST WAS TO INCREASE CLOUDS AND ADD A SLIGHT CHANCE OF
SHOWERS NEAR OUR NORTHERN BORDERS WITH WYOMING AND NEBRASKA.
COLDER AIR WILL MOVE IN BEHIND THE COLD FRONT AND HAVE LOWERED
FRI MORNING LOWS AND FRIDAY AFTERNOON HIGHS. COULD BE COLD ENOUGH
FRI AM FOR FREEZE/FROST POTENTIAL WITH READINGS IN THE LOWER 30S.
MAY NEED HILITES SINCE A PORTION OF LOWER ELEVATIONS HAVE NOT HAD
A HARD FREEZE YET.

FOR THE WEEKEND AND INTO EARLY NEXT WEEK...COLORADO WILL BE UNDER
A DECREASING NORTHWEST FLOW PATTERN. CONDITIONS WILL BE DRY
THROUGH THIS PERIOD WITH A WARMING TREND. VERY FEW CHANGES TO OUT
PERIODS NEXT WEEK.

&&

.AVIATION...(FOR THE TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 400 AM MDT WED OCT 1 2014

SKIES WILL STEADILY FILL WITH CLOUDS THIS MORNING FOLLOWING THE
PASSAGE OF WEAK COLD FRONT AROUND MID-MORNING. LOOK FOR LIGHT SLY
WINDS TO SHIFT TO AN EAST-NORTHEAST COMPONENT AT 7-12 KTS BY AROUND
15Z. A SECOND PUSH OF COOL...MOIST AIR THIS AFTERNOON WILL
PROBABLY SET OFF THE MAIN BATCH OF SHOWERY PRECIPITATION ALONG
THE FRONT RANGE AND IN THE DENVER AREA. SHOWERS MAY BE ACCOMPANIED
BY A FEW THUNDERSTORMS CAPABLE OF LIGHT TO MODERATE RAINFALL. CIGS
ARE LIKELY TO LOWER TO BELOW 5000 FT AGL AFTER 22Z TODAY AND
POSSIBLY BELOW 3000 FT AGL WITH A COLD RAINFALL THIS EVENING.
VSBYS MAY ALSO LOWER TO 2-3 MILES AT TIMES WITH THE PCPN.
CONDITIONS SHOULD STEADILY IMPROVE AFTER MIDNIGHT AS DRIER...
STABLE AIR SPREADS IN FROM THE NORTHWEST. ALTHOUGH POCKETS OF
SHALLOW DENSE FOG WILL BE POSSIBLE SHOULD SKIES CLEAR BEFORE
SUNRISE.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...WINTER WEATHER ADVISORY FOR THE
NORTH CENTRAL MOUNTAIN ZONES 31..33>34 FROM 12 PM MDT TODAY TO 12
AM MDT TONIGHT.

&&

$$

SHORT TERM...BAKER
LONG TERM...ENTREKIN
AVIATION...BAKER



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.