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000
FXUS65 KGJT 081113
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
412 AM MST SAT MAR 8 2014

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 412 AM MST SAT MAR 8 2014

A DEFORMATION ZONE...BETWEEN YESTERDAY/S TROUGH AND AN UPSTREAM
SHORTWAVE RIDGE...WILL CONTINUE TO PRODUCE AREAS OF SNOW OVER THE
CENTRAL...AND ESPECIALLY THE SOUTHERN MOUNTAINS INTO THE MORNING
HOURS. THE SNOW WILL REMAIN ON THE LIGHT SIDE AS THE FLOW BECOMES
NORTHEAST WHICH IS MORE DOWNSLOPE FOR OUR SIDE OF THE DIVIDE. BY
AFTERNOON...THE REMAINING SHOWERS WILL MOSTLY BE OVER THE SOUTHERN
MOUNTAINS WHERE A REMNANT OF THE DEFORMATION ZONE WILL PERSIST.
AFTERNOON HEATING WILL ALSO HELP BY PROVIDING SOME LOW LEVEL
LIFT...BUT THESE ELEMENTS REMAIN UNIMPRESSIVE AT BEST.

IN THE MEAN TIME...THE AFOREMENTIONED RIDGE WITH ITS AXIS BECOMING
EAST-WEST ORIENTED...WILL APPROACH FROM THE NORTH. DRIER AND MORE
STABLE AIR WILL MOVE IN AHEAD OF THE RIDGE FROM NORTH TO SOUTH
TODAY. THEREFORE SUNNY/MOSTLY SUNNY CONDITIONS WILL BE EXPECTED
OVER THE NORTHERN PORTION. THE RIDGE AXIS IS PROGGED TO REACH THE
CO/WY BORDER BETWEEN MIDNIGHT TONIGHT AND AROUND 3 AM SUN
MORNING...THEN SLOWLY SLIDE ACROSS THE FORECAST AREA THROUGH
SUNDAY. BY EVENING TONIGHT ANY REMAINING SNOW SHOWERS OVER THE SAN
JUANS WILL QUICKLY END...WITH MOSTLY CLEAR SKIES AREA-WIDE BY
MIDNIGHT. TEMPS WILL WARM TO ABOVE NORMAL VALUES ON SUN UNDER
SUNNY TO MOSTLY SUNNY SKIES.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 412 AM MST SAT MAR 8 2014

RIDGE FLATTENS IN RESPONSE TO A PACIFIC TROUGH WHICH MOVES ASHORE
OVER THE NORTHWEST LATE SUNDAY NIGHT. AS THE SHORTWAVE PACIFIC
TROUGH MOVES OVER THE NORTHERN INTERMOUNTAIN REGION ON MONDAY THE
HEIGHT GRADIENT WILL TIGHTEN...ESPECIALLY NORTH...RESULTING IN
BREEZY AND MILD AFTERNOON CONDITIONS. PRECIPITATION HOLDS OFF A
BIT LONGER THAN EARLIER RUNS HAD SUGGESTED SO PARED BACK POPS
ACROSS ALL BUT THE EASTERN UINTA MOUNTAINS MONDAY AFTERNOON.

THE TROUGH DEVELOPS A BIT OF A POSITIVE TILT MONDAY NIGHT AS IT
SAGS SOUTHWARD ACROSS THE NORTH WITH COLDER AIR FILTERING IN
BEHIND THE COLD FRONT ASSOCIATED WITH THIS SYSTEM. MODELS DIFFER
IN DEPTH WITH NAM THE SHALLOWEST AND THE ECMWF DEEPEST. DESPITE
DIFFERENCES...MODELS WERE SIMILAR IN TIMING OF MOISTURE WITH
NORTHERN MOUNTAINS FAVORED. DEEPER EC SPREADS MOISTURE FURTHER
SOUTH AND LEFT CHANCE POPS ALONE THERE FOR NOW...BUT DID INCREASE
POPS TO LIKELY IN THE NORTH GIVEN BETTER MODEL AGREEMENT THERE.

PRECIPITATION CHANCES PERSIST TUESDAY AS THE SYSTEM CONTINUES TO
SAG SOUTHWARD. SNOW LEVELS WILL BE LOWERING WITH THE INFLUX OF
COLDER AIR AND THE NORTHERN VALLEYS STAND A GOOD CHANCE OF SEEING
ACCUMULATING SNOW. AFTERNOON HIGHS WILL DIP BY ABOUT 10 DEGREES
WITH FRONTAL PASSAGE ACROSS THE NORTH WITH A AROUND 5 DEGREES OF
COOLING SOUTH.

DURING THE MIDDLE OF THE WEEK MODELS INDICATED FLOW WILL SPLIT
WITH A MID-LEVEL LOW SPLITTING OFF FROM THE MAIN SYSTEM...THEN
RETROGRADING OVER THE SOUTHERN GREAT BASIN. DURING THIS TIME
SHOWERS DIMINISH TUESDAY NIGHT INTO WEDNESDAY MORNING ONLY TO
REDEVELOP OVER THE SOUTHERN MOUNTAINS DURING THE AFTERNOON BENEATH
AN AREA OF STRETCHING DEFORMATION. AS THE CLOSED LOW BECOMES
ENTRAINED IN THE MAIN FLOW AGAIN WEDNESDAY NIGHT INTO THURSDAY
THERE WILL BE A CONTINUED CHANCE FOR MOUNTAIN SNOW ACROSS THE
SOUTHERN MOUNTAINS INTO THURSDAY NIGHT ACCORDING TO THE GFS...
THOUGH THE ECMWF IS DRY DURING THIS PERIOD. GIVEN MODEL
DIFFERENCES WILL LEAVE THE LOW CHANCE POPS GENERATED FROM MODEL
BLENDS. DRY CONDITIONS RETURN AT THE END OF THE WEEK. AFTER
ANOTHER COOL DAY WEDNESDAY...TEMPERATURES WILL BEGIN TO SLOWLY
MODERATE DURING THE LATTER PART OF THE COMING WEEK.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 412 AM MST SAT MAR 8 2014

THE TRAILING EDGE OF THE EXITING STORM WILL CONTINUE TO BRING
SCATTERED SHOWERS TO THE SOUTHERN AND CENTRAL COLORADO MOUNTAINS
THROUGH 18Z. SNOWFALL WILL RESULT IN AREAS OF MOUNTAIN
OBSCURATION. MEANWHILE...LOW STRATUS PUSHING AGAINST THE NORTHWEST
FACES OF THE NORTHERN AND NORTH-CENTRAL COLORADO MOUNTAINS WILL
ALSO OBSCURE MOUNTAINS AND WILL MAINTAIN MVFR/IFR CIGS FOR
AIRFIELDS EAST OF A KHDN-KEEO-KGWS-KGUC-KALS LINE THROUGH 16Z. LOW
CLOUDS WILL BURN OFF FROM 16Z TO 19Z.

AFTER 19Z SHOWERS WILL BE ISOLATED OVER THE SAN JUAN MOUNTAINS
WITH ONLY LOCALIZED MOUNTAIN OBSCURATION. THE REMAINDER OF THE
FORECAST AREA WILL HAVE VFR CONDITIONS AFTER 19Z.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...NONE.

UT...NONE.

&&

$$

SHORT TERM...EH
LONG TERM...NL
AVIATION...NL