FXUS65 KPUB 070311 AAB
AFDPUB
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PUEBLO CO
811 PM MST SUN DEC 6 2009
.UPDATE...
AM HOISTING A WINTER WX ADVISORY FOR THE SANGRE DE CRISTO
RANGE...SPANISH PEAKS...AND CHAFFEE COUNTY STARTING AT 18Z.
TOMORROW. BULK OF THE HEAVIER SNOW WILL PROBABLY HOLD OFF TIL
TUE MORNING...BUT WITH NO REAL BREAK MON NIGHT WILL RUN THE
ADVISORY STRAIGHT THROUGH TUE AFTERNOON. COULD SEE LOCAL WARNING
CRITERIA FOR THE HIGHER ELEVATIONS...BUT BULK OF THE SANGRE ZONES
SHOULD FALL UNDER ADVISORY CRITERIA. BLOWING/DRIFTING SNOW AND LOW
WIND CHILLS WILL ALSO BE AN ISSUE...PARTICULARLY FOR THE HIGHER
ELEVATIONS. ALSO CONSIDERED ADDING PORTIONS OF THE SAN LUIS
VALLEY...SINCE ADVISORY CRITERIA SNOWFALL IS PROBABLY GOING TO
OCCUR INVOF THE MTNS. HOWEVER...KALS AREA MAY NOT SEE THAT MUCH
SNOWFALL. WILL LET THE NEXT SHIFT TAKE A CLOSER LOOK. ROSE
&&
.PREV DISCUSSION... /ISSUED 610 PM MST SUN DEC 6 2009/
UPDATE...
SNOW WINDING DOWN ACROSS THE CENTRAL MTS AND WV SHOWING GOOD
DRYING MOVING IN. HAVE ALLOWED THE WINTER WEATHER ADVISORY FOR THE
HIGHER ELEVATIONS OF THE SAWATCH AND MOSQUITO RANGES TO EXPIRE.
MAY NEED TO HOIST SOME HIGHLIGHTS (MOST LIKELY ADVISORIES) FOR
THE SANGRES AND UPPER ARKANSAS RIVER VALLEY FOR THE MON AND TUES
STORM BUT WILL WAIT FOR 00Z RUNS BEFORE MAKING ANY OTHER CHANGES.
-KT
PREV DISCUSSION... /ISSUED 309 PM MST SUN DEC 6 2009/
SHORT TERM...
(TONIGHT AND TOMORROW)
.MAJOR WINTER STORM TO AFFECT THE MTNS ALONG THE CONTDVD
ESPECIALLY THE SW MTNS...
CURRENTLY...
AREA CURRENTLY IN BETWEEN 2 WEATHER SYSTEM. FIRST SYSTEM HAS MOVED
OUT AND BROUGHT SOME GOOD SNOW TOTAL TO THE C MTN REGION. AREAS IN
AND AROUND THE PIKES PEAK REGION ALSO OBSERVED SEVERAL INCHES. SAT
PIX AND SFC OBS SHOW IT IS MOSTLY CLOUDY TO CLOUDY ON THE PLAINS AND
IT IS COLD. TEMPS AT THIS HOUR (2 PM) ARE IN THE TEENS AND LOWER
20S. EVEN THOUGH COLDER AIR IS MOVING IN...SFC PRESSURES ARE
BEGINNING TO FALL ON THE PLAINS IN ADVANCE OF THE NEXT SYSTEM WHICH
IS MOVING TOWARD THE REGION. THE VORT CENTER WITH THIS 2ND SYSTEM IS
CURRENTLY LOCATED OVER THE OREGON COAST AND IT IS MOVG SOUTH DOWN
THE PAC COAST. A BAND OF SUBTROPICAL MOISTURE WAS OBSERVED KNIFING
IN INTO S CALIF.
REST OF TODAY AND TONIGHT...
MAIN CONCERN TONIGHT IS TEMPS AND CLOUDS AND POSSIBLE SOME LIGHT
SNOW IN AREAS.
WITH PRESSURES FALLING ON THE PLAINS AS THE WESTERN STORM
INTENSIFIES...GOOD UPSLOPE FLOW WILL DEVELOP. ANY PARTIALLY CLEARING
SKIES THIS AFTERNOON SHOULD SOCK IN RATHER QUICKLY AND CIGS WILL
LIKELY BECOME QUITE LOW OVER THE AREA. I WOULD ALSO NOT BE SURPRISED
IF SOME STEADY LIGHT SNOW FORMS ON TOP OF THE PALMER DIVIDE GIVEN
THE UPSLOPE. SNOWFALL VALUES SHOULD BE LIGHT (<2" FLUFF IF THAT).
OVER THE LOWER ELEVATIONS OF THE 4 CORNERS REGION IT WAS RATHER
CLOUD FREE AND WAT VAP WAS ALSO NOT SHOWING MUCH MSTR. THIS WILL
LIKELY CONTINUE INTO THE EVENING HOURS BUT WILL QUICKLY CHANGE
DURING THE EARLY MORNING HOURS SUNDAY AS MSTR AND WINDS INCREASE.
STEADY SNOW SHOULD BEGIN FALLING IN EARNEST ACROSS THE SW FACING
SLOPES OF THE SAN JUANS TOWARDS SUNRISE.
TOMORROW...
SEE NO REASON TO CHANGE ANY HIGHLIGHTS. THERE IS ONLY ONE WORD FOR
THE MODEL QPF VALUES OVER THE SAN JUANS AND THAT IS ... INSANE. IT
IS GOING TO SNOW AND BLOW OVER THE SW MTNS...ESPECIALLY TOMORROW
AFTERNOON. SNOWFALL RATES WILL LIKELY BE IN THE 1-2 AND MAYBE 3/HR"
RANGES THROUGH A GOOD PART OF THIS STORM. C MTNS WILL ALSO SEE
STEADY SNOWFALL BUT WINDS SHOULD BE CONSIDERABLY LESS ALONG WITH
SNOWFALL RATES. THE BEST SNOWS ACROSS THE C MTNS WILL LIKELY COME
WELL AFTER THIS TIME PD.
SNOWS WILL BEGIN TO PICK UP ACROSS THE REST OF THE REGION BY
TOMORROW AFTERNOON. WITH THE COLD AIR IN PLACE AND WAA STARTING TO
DEVELOP...LIGHT SNOW SHOULD REDEVELOP OVER THE PLAINS BY TOMORROW
AFTERNOON. SNOW SHOULD BE LIGHT BUT STEADY. TEMPS TOMORROW WILL ONCE
AGAIN BE COLD WITH HIGHS IN THE UPPER TEENS TO MID 20S. A STEADY SE
WIND WILL MAKE IT FEEL COLDER. \/34
LONG TERM...
(MONDAY NIGHT THROUGH SUNDAY)
WELL ADVERTISED UPPER TROUGH WILL BE DIGGING ACROSS THE GREAT
BASIN INTO THE DESERT SOUTHWEST MONDAY NIGHT BEFORE MOVING OVER
THE REGION ON TUESDAY. THE FIRST IN A SERIES OF VORT MAXES WILL
EJECT OUT OVER SOUTHWEST COLORADO MONDAY NIGHT WITH A STRONG UPPER
LEVEL JET WRAPPING AROUND THE TROUGH. ABUNDANT SUBTROPICAL
MOISTURE AND FAVORABLE OROGRAPHICS WILL ACCOMPANY THIS FIRST WAVE
SETTING THE STAGE FOR HEAVY SNOWFALL OVER THE EASTERN SAN JUANS.
SNOW IS FORECAST TO BE ONGOING MONDAY EVENING AND PICK UP IN
INTENSITY AS THE UPPER SYSTEM APPROACHES. EXPECT BLIZZARD
CONDITIONS OVER THE EASTERN SAN JUANS MONDAY NIGHT THROUGH TUESDAY
WITH STRONG WINDS GUSTING TO NEAR 60 KTS AND HEAVY SNOWFALL. MAIN
TROUGH MOVES ACROSS THE REGION DURING THE DAY ON TUESDAY. ONE
CONCERN MAY BE WIND DIRECTION IMPACTING OROGRAPHICS. MODELS STILL
STRUGGLING A BIT WITH STORM TRACK. PREFER THE GFS TRACK WHICH IS A
TAD BIT FURTHER SOUTH AND WOULD HAVE FAVORABLE SOUTHWEST FLOW
THROUGH MUCH OF TUESDAY AFTERNOON. A QUICK LOOK AT THE 18Z NAM IS
ALSO TRENDING WITH THE GFS SOLUTION. NAM CONTINUES TO BE THE MOST
AGGRESSIVE AT SNOW AMOUNTS WITH THE GFS AND MM5 NOT FAR BEHIND.
GOING SNOW TOTALS STILL LOOK ON TRACK WITH 2 TO 4 FEET IN THE
EASTERN SAN JUANS WITH LOCALIZED AMOUNTS APPROACHING 5 FEET BY THE
TIME THE STORM WRAPS UP. SNOW WILL ALSO BE ONGOING ACROSS THE
CENTRAL MOUNTAINS MONDAY NIGHT AND PERSIST THROUGH TUESDAY.
THE HEAVIEST SNOW OVER THE CENTRAL MOUNTAINS MAY HOLD OFF UNTIL
TUESDAY AFTERNOON AS THE UPPER TROUGH BEGINS TO SHIFT TO THE EAST
AND MORE FAVORABLE NORTHWESTERLY OROGRAPHIC FLOW SETS UP. GOING
WINTER STORM WARNINGS LOOK GOOD WITH 1 TO 3 FEET OF SNOWFALL IN THE
HIGHER ELEVATIONS. WINDS WILL ALSO BE BREEZY CREATING BLOWING
SNOW AND HAZARDOUS DRIVING CONDITIONS. SNOW WILL SPREAD EASTWARD
INTO THE SANGRE DE CRISTOS ON TUESDAY WHERE ADVISORY LEVEL SNOW
AMOUNTS WILL BE POSSIBLE.
THE AREA OF LEAST CONFIDENCE CONTINUES TO BE THE EASTERN PLAINS.
SURFACE LOW IS FORECAST TO DEVELOP OVER SOUTHEAST COLORADO BY
TUESDAY MORNING AND SHIFT INTO KS BY TUESDAY EVENING. MODELS
HAVING A HARD TIME WITH THE POSITION OF THE SURFACE LOW WITH THE
NAM FURTHEST SOUTH AND GFS NORTH. STRONG MIXING WILL ALLOW FOR
TEMPERATURES TO WARM UP TUESDAY AFTERNOON ALONG THE LEE SLOPES OF
THE WET MOUNTAINS WHILE THE PLAINS WILL REMAIN IN COLD UPSLOPE
FLOW. AREAS NORTH OF HIGHWAY 50 WILL LIKELY SEE A WINDOW OF
HEAVIER SNOWFALL TUESDAY AFTERNOON AS THE UPPER TROUGH AND SURFACE
LOW MIGRATE ACROSS THE AREA. WHERE THE LOW TRACKS WILL DETERMINE
WHERE SNOW WILL FALL ON THE PLAINS. THE OTHER MAIN CONCERN FOR THE
PLAINS WILL BE WINDS TUESDAY AFTERNOON AND EVENING BEHIND THE
SURFACE COLD FRONT. NORTHERLY WINDS WILL GUST IN THE 30 TO 40 KT
RANGE ALONG THE KS/CO BORDER WITH VERY COLD AIR WORKING INTO
PLACE.
UPPER TROUGH WILL SHIFT EAST OF THE AREA TUESDAY NIGHT WITH
NORTHWESTERLY FLOW SETTING UP ACROSS THE ROCKIES THROUGH THURSDAY.
WEAK EMBEDDED ENERGY AND FAVORABLE UPSLOPE FLOW WILL KEEP SNOW IN
THE FORECAST FOR THE CENTRAL MOUNTAINS THROUGH THURSDAY.
TEMPERATURES WILL STRUGGLE TO WARM ACROSS THE EASTERN PLAINS WITH
NORTHERLY FLOW ADVECTING COLD AIR INTO THE REGION. HIGHS WILL BE
IN THE 2OS AND 30S WEDNESDAY AND THURSDAY OVER THE EASTERN PLAINS.
FLOW TURNS WESTERLY BY FRIDAY WITH EMBEDDED SHORTWAVES PASSING
ACROSS THE AREA. LOW CONFIDENCE IN TIMING AND AMOUNT OF
PRECIPITATION THIS FAR OUT...HOWEVER THIS WILL ALLOW FOR
TEMPERATURES TO GRADUALLY WARM THROUGH THE WEEKEND. 88
AVIATION...
FOR KCOS AND KPUB...CIGS HAVE COME UP ABOVE MVFR THIS AFTERNOON BUT
I ANTICIPATE THEY WILL QUICKLY GO BELOW MVFR AND RANGE IN THE IFR
AND LIFR BY EARLY THIS EVENING. THIS WILL BE DUE TO INCREASING E-SE
SFC WINDS. THERE WILL LIKELY BE SOME SNOW SHOWERS TO DEAL WITH WITH
SOME LIGHT STEADY SNOW MORE LIKELY N OF KCOS. FOR NOW NOT EXPECTING
MUCH IN THE WAY OF ACCUMULATIONS TONIGHT.
FOR TOMORROW...LOW CLOUDS AND CIGS WILL CONTINUE THROUGH THE DAY AS
FLOW REMAINS UPSLOPE. SNOW MAY BECOME STEADIER ACROSS THE TAF
SITES...ESPECIALLY TOMORROW AFTERNOON.
FOR KALS...MOSTLY CLEAR SKIES WILL LAST INTO THIS EVENING BUT EXPECT
SKIES TO CLOUD UP AS THE NIGHT PROGRESSES. WILL LIKELY SEE SOME SNOW
SHOWERS BY TOMORROW MORNING ACROSS THE VALLEY AS BLOW-OVER FROM THE
SAN JUANS IMPINGES ON THE TAF SITE. \/34
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 11 AM MONDAY TO 5 PM MST TUESDAY
FOR COZ062-072>075.
WINTER STORM WARNING FROM 5 AM MONDAY TO 5 PM MST TUESDAY FOR
COZ058>061-064-065-067.
BLIZZARD WARNING FROM 5 AM MONDAY TO 5 PM MST TUESDAY FOR COZ066-
068.
&&
$$
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