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000
FXUS65 KPUB 021140
AFDPUB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PUEBLO CO
440 AM MST MON DEC 2 2013

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 332 AM MST MON DEC 2 2013

...HIGH WIND POTENTIAL ESPECIALLY IN AND NEAR THE EASTERN
MOUNTAINS...

STRONG PACIFIC JET STREAM BEGINNING TO BEAR DOWN ON COLORADO WITH A
GUST TO 67 MPH AT 117 AM AND A GUST TO 79 MPH ON TOP OF PIKES PEAK
AT 210 AM.  SINCE THEN...THOSE SPEEDS HAVE COME DOWN SOME WITH THE
MOST RECENT REPORTS INDICATING GUSTS TO 58 MPH AT MONARCH AND NO NEW
GUSTS REPORTED FROM PIKES PEAK.  COTTONWOOD PASS HAS BEEN WINDY THIS
MORNING TOO.  GUSTS TO 63 MPH ARE BEING REPORTED CURRENTLY FROM THE
AWOS SENSOR IN THE EASTERN SAWATCH RANGE SOUTHWEST OF BUENA VISTA.

IT WILL CONTINUE WINDY TODAY...ESPECIALLY IN AND NEAR THE CENTRAL
AND EASTERN MOUNTAINS.  BUT...H7 WIND SPEED FORECASTS HAVE COME DOWN
CONSIDERABLY FROM EARLIER RUNS FOR TODAY...SO BELIEVE THE WARNING
LEVEL HIGH WIND THREAT WILL HOLD OFF UNTIL TONIGHT.  STILL GUSTS TO
60 MPH OR SO IN THE MOUNTAINS...AND 50 MPH OR SO NEAR THE
MOUNTAINS...BUT PROBABLY STAYING BELOW WARNING CRITERIA.  THERE
COULD BE AN ISOLATED REPORT OVER 75 MPH...BUT I DON`T THINK IT WILL
BE WIDESPREAD ENOUGH FOR A WARNING TODAY. CONSEQUENTLY...THE START
OF THE HIGH WIND WATCH HAS BEEN PUSHED BACK UNTIL TONIGHT.

THIS EVENING...THE STRONG PACIFIC JET STREAM WILL MOVE OVER SOUTHERN
COLORADO BRINGING THE POTENTIAL FOR HIGH WINDS...MAINLY IN AND NEAR
THE EASTERN MOUNTAIN RANGES. H7 WINDS UP TO 75 KNOTS AND STRONG
DOWNSLOPE PRESSURE GRADIENTS ALONG THE EAST SLOPES OF THE MOUNTAINS
SHOULD MAKE FOR SOME VERY HIGH WINDS.  GUSTS OVER 75 MPH WILL BE
POSSIBLE IN THE MOUNTAINS AND GUSTS OVER 60 MPH WILL BE POSSIBLE
OVER THE LOWER AREAS ADJACENT TO THE MOUNTAINS. THIS THREAT WILL
ESCALATE BETWEEN 03Z AND 06Z...PERSIST THROUGH 12Z...AND THEN
DEESCALATE BETWEEN 12Z AND 15Z.  THE PRIMARY AREA OF CONCERN IS THE
EASTERN MOUNTAINS AND ADJACENT AREAS...MAINLY ALONG AND WEST OF I-25.

ON A FINAL NOTE...SNOW WILL BEGIN MOVING INTO THE HIGH COUNTRY
OVERNIGHT BUT IT LOOKS LIKE THE BULK OF IT WILL HOLD OFF UNTIL AFTER
09Z AND BE CONFINED MAINLY TO THE CENTRAL MOUNTAINS NORTH OF
COTTONWOOD PASS.  SO...THE START TIME OF THE WATCH THAT WAS IN
EFFECT FOR THE CONTINENTAL DIVIDE HAS BEEN PUSHED BACK A LITTLE TO
12Z.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 332 AM MST MON DEC 2 2013

A LONGWAVE TROUGH OVER THE WESTERN HALF OF THE COUNTRY WILL
ESSENTIALLY REMAIN IN PLACE THROUGH THE EXTENDED FORECAST
PERIOD...KEEPING COLD AIR AND THE THREAT OF SNOW FOR THE CWA THROUGH
SUNDAY. THE NAM...GFS AND EC MODELS ARE IN FAIRLY GOOD
AGREEMENT...BUT THERE IS ONE SIGNIFICANT DIFFERENCE TO START OFF THE
EVENT.

TUESDAY...SNOW MOVES INTO THE CONTDVD RIGHT AROUND 12Z TUE
MORNING...AND PERSISTS THROUGH WED. LATEST MODEL RUNS DID NOT SHOW
MUCH ACTIVITY SAVE FOR WIND PRIOR TO THIS TIME...SO AMENDED ONGOING
WATCH FOR A SLIGHTLY LATER STARTING TIME. WHILE SNOW IS OCCURRING
ALONG THE CONTDVD...A SFC HIGH WILL DROP SOUTH ALONG THE MIDSECTION
OF THE COUNTRY WHICH WILL PUSH A FAIRLY STRONG COLD FRONT INTO
COLORADO. THE MODEL DISAGREEMENT DEALS WITH TIMING OF THE FRONTAL
PASSAGE AND THE RESULTANT MAX TEMP PRIOR TO PASSAGE. THE NAM PUSHES
THE COLD FRONT SOUTH ACROSS THE PALMER DVD RIGHT AROUND 21Z...WHILE
THE GFS HAS IT ALREADY CROSSING THE DVD BY 18Z. THIS 3-5 HR
DIFFERENCE WILL GREATLY AFFECT EXPECTED MAX TEMPS FOR THE PLAINS.
TAKING INTO ACCT THAT FRONTS USUALLY MOVE A BIT FASTER THAN MODELS
NORMALLY INDICATE...WILL SPLIT THE DIFFERENCE AND TRY TO SHOW A
TAPERED MAX T GRID ON TUE FROM NORTH TO SOUTH...WITH TAD AND THE
SOUTHERN BORDER WARMING INTO THE LOWER 50S. TEMPS ARE THEN EXPECTED
TO QUICKLY FALL THROUGH THE AFTN. ONE OTHER THING TO NOTE...BRISK
WINDS THROUGH THE PRIOR NIGHT AND EARLY TUE MORN WILL KEEP THE
MORNING TEMPS HIGHER THAN NORMAL...WHICH MEANS THE WARMING FOR THE
DAY WILL GET A HEAD START. PCPN THAT WILL INITIALLY BE AFFECTING THE
CONTDVD TUE MORN...WILL THEN SPREAD TO THE E MTS AND ADJACENT PLAINS
WITH FRONTAL PASSAGE...AND BY TUE NIGHT MUCH OF THE FORECAST AREA
WILL BE COLD WITH A GOOD CHANCE OF SEEING SOME SNOW.

WEDNESDAY THROUGH SUNDAY...IT IS HARD TO PINPOINT EXACT TIMING AND
SNOW AMOUNTS THROUGH THE REMAINDER OF THE EXTENDED PERIOD...BUT THE
UPPER TROUGH REMAINS IN PLACE. TAKING A BLEND OF THE EC AND GFS
MODELS...THERE WILL BE AN ENHANCED PROBABILITY OF SNOW ACROSS THE
AREA WED AND THU...PERHAPS A BREAK ON FRI...THEN A SECOND ROUND FOR
SAT INTO SUN AS ANOTHER LOBE OF ENERGY ROTATES ACROSS COLORADO. SFC
HIGH PRESSURE REMAINS FIRMLY IN PLACE ACROSS THE CENTRAL US THROUGH
THE ENTIRE PERIOD...SO EASTERLY UPSLOPE SFC FLOW WILL PERSIST. LOOK
FOR HIGH TEMPS IN THE TEENS TO LOWER 20S...AND MIN TEMPS FROM 10
BELOW TO 10 ABOVE ZERO EACH DAY. AS FOR SNOW AMOUNTS...THE HIGHEST
AMOUNTS FORECAST FOR THE WATCH AREA COMES IN BETWEEN ONE TO TWO FEET
OF NEW SNOW. FOR THE REST OF THE CWA...THE E MTS AND I25 CORRIDOR
COULD SEE 2-6 INCHES FOR THE LOWER ELEVATIONS...AND IN EXCESS OF 8
INCHES FOR THE HIGHER ELEVATIONS OVER A 36 TO 48 HR PERIOD.

THIS WILL BE AN EXCEPTIONAL PERIOD OF COLD FOR SOUTHERN COLORADO.
PREPARE YOUR HOME...AUTO OR BUSINESS. CHECK YOUR FURNACE. INSULATE
EXPOSED WATER PIPES. MAKE SURE YOUR CAR HAS A STRONG BATTERY...
PROPER ANTIFREEZE PROTECTION AND A GOOD SET OF ALL SEASON OR SNOW
TIRES. MAKE SURE YOUR KIDS DRESS WARMLY BEFORE HEADING TO SCHOOL AND
GIVE YOUR PETS ADEQUATE SHELTER FROM THE COLD. THIS WILL BE AN
UNUSUALLY LONG PERIOD FOR SOUTHERN COLORADO TO BE IN THE DEEP
FREEZE. GET READY FOR IT NOW WHILE THE TEMPERATURES ARE STILL MILD.
MOORE

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 332 AM MST MON DEC 2 2013

SAVE FOR AREAS OF NIGHT AND MORNING FOG AND LOW CLOUDS IN THE SAN
LUIS VALLEY...GENERALLY VFR EXPECTED ACROSS THE LOWER ELEVATIONS
THROUGH 12Z TUESDAY.  POCKETS OF MVFR/IFR/LIFR CONDITIONS WILL BE
FOUND ALONG THE CONTINENTAL DIVIDE ASSOCIATED WITH INCREASING LEVELS
MOISTURE STREAMING IN FROM THE PACIFIC NORTHWEST.  OTHER CONCERN IS
THE WINDS.  HIGH WINDS WILL BE POSSIBLE ACROSS THE FLIGHT AREA
THROUGH EARLY TUESDAY...MAINLY ALONG AND NEAR THE CENTRAL AND
EASTERN MOUNTAINS.  GUST POTENTIAL TO 75 MPH IN THE MOUNTAINS WITH
GUST POTENTIAL TO 60 MPH NEAR THE MOUNTAINS...ESPECIALLY FROM THE
EASTERN MOUNTAIN RANGES TO I-25...03Z-15Z. LW

&&

.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM LATE TONIGHT THROUGH WEDNESDAY AFTERNOON
FOR COZ058>061-066-068.

HIGH WIND WATCH FROM THIS EVENING THROUGH TUESDAY MORNING FOR
COZ072>075-078>082-084-085-087.

&&

$$

SHORT TERM...LW
LONG TERM...MOORE
AVIATION...LW