000
FXUS65 KGJT 051730
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1030 AM MST WED MAR 5 2014

.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 400 AM MST WED MAR 5 2014

00Z HAND ANALYSIS AT H5 AND H7 SHOWED THE TROF AXIS AND WEAK MID
LEVEL FRONT OVER WESTERN COLORADO. CURRENT WATER VAPOR IMAGERY SHOWS
THIS SYSTEM HAS NOW TRANSLATED THE ROCKIES AND IS MOVING INTO THE
SOUTHERN HIGH PLAINS. DISTINCT DARKENING ON BACK SIDE INDICATIVE OF
THE CONVECTIVE NATURE OF THE PRECIPITATION THROUGH LATE LAST
EVENING...WITH PRECIPITATION LIMITED TO THE WESTERN DIVIDE AND
POINTS EAST. SNOTELS AND REPORTS INDICATED 6 TO 9 INCHES IN THE
NORTHERN MOUNTAINS WITH 4 TO 7 IN THE CENTRAL AND NORTHERN SAN
JUANS. THE MAIN CONCERN NOW WITH DRY AIR MOVING IN ALOFT IS
DEVELOPING STRATUS AND FOG. VSBYS HAVE BEEN THE LOWEST IN THE EDGE
OF THE LOWER CLOUD DECKS WITH SWINGS FROM 1/4 STATUTE MILE TO 10
MILES AND CLOUDS BUILD IN OR ERODE. MEEKER HAS BEEN THE MOST
PERSISTENT AT STAYING IN FZFG BUT RECENTLY HAS GONE UP WITH CLOUDS
BUILDING IN. THEREFORE WITH CONFIDENCE LOW ON COVERAGE AND
PERSISTENCE...WILL HOLD OFF ON ANY ADVISORIES AND PUT FOG WORDING IN
FORECAST THROUGH FIRST FEW HOURS AROUND SUNRISE.

THERE WILL BE A SHORT BREAK TO START OUT THIS FORECAST AS FLAT
RIDGING WILL BE BUILDING THROUGH TONIGHT...THEN SHIFT EAST OF THE
ROCKIES ON THURSDAY AS THIS PROGRESSIVE FLOW BRINGS IN ANOTHER BATCH
OF MOISTURE AND ENERGY INTO THE WEST. ASSUMING STRATUS BEHAVES AND
DISSIPATES A MAINLY SUNNY DAY WILL BE IN STORE AS THIN HIGH
CLOUDINESS AND SOME MOUNTAIN TOP CLOUDS DRIFT BY. TEMPERATURES WILL
BE BATTLING WEAK MIXING TODAY AS WARMER AIR SLIDES BACK IN ALOFT.
DID LEAN TOWARD THE COOLER SIDE OF GUIDANCE...BUT FOR THE MOST PART
TEMPERATURES WILL BE NEAR OR SLIGHTLY ABOVE NORMAL.

MOISTURE TOPPING THE RIDGE ON WEDNESDAY NIGHT WILL THICKEN THE HIGH
CLOUDINESS GOING INTO THURSDAY. THIS MOISTURE WILL BE DIRECTED MORE
OVER OUR CWA GOING INTO THURSDAY AS WINDS BACK TO THE SOUTHWEST WITH
THE RIDGE AXIS TRANSITIONING EAST OF THE ROCKIES. THE UPSTREAM WAVE
WILL BE GRADUALLY ADDING WEAK BROAD SCALE ASCENT THURSDAY AFTERNOON
AND SOME LIGHT WARM ADVECTIVE SHOWERS MAY DEVELOP OVER THE
NORTHERN MOUNTAINS LATE IN THE AFTERNOON. HOWEVER THE BULK OF THE
FORCING WILL STILL BE TO OUR WEST SO POPS REMAIN LOW. TEMPERATURES
LOOK TO WARM NICELY IN THIS PATTERN WITH INCREASED MIXING HELPING
TO PUSH TEMPERATURES SOME 5 TO 8 DEGREES ABOVE NORMAL.

.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 400 AM MST WED MAR 5 2014

ACTIVE COLD FRONT WILL BE MOVING INTO NE UTAH THURSDAY NIGHT...
REACHING THE I70 CORRIDOR AROUND 12Z FRIDAY...THEN SWEEPS
SOUTHWARD DURING THE DAY. DECENT BAROCLINICITY EXISTS WITH THE
FRONT AS IT MOVES INTO THE WESTERN SLOPE. GIVEN THE NIGHTTIME AND
MORNING PASSAGE OF THE FRONT...ACCUMULATING SNOWFALL IN THE HIGH
COUNTRY IS LIKELY AND SHOULD IMPACT MORNING TRAVEL ABOVE 7500
FEET. QG ASCENT PRIMARILY EXISTS WITH THE FRONTAL PASSAGE. MODEL
QPF AND WPC GUIDANCE SUGGEST THAT SNOW POTENTIAL IS BELOW WARNING
CRITERIA AND DOES MERIT HOISTING A WATCH AT THIS TIME. ANOTHER
LIMITING FACTOR FOR SNOW PRODUCTION IS THAT 700 MB TEMPS STAY
WARMER THAN -8C AND THE GRADIENT FLOW WEAKENS IN THE POST FRONTAL
AIR MASS. AIR MASS BECOMES CONVECTIVE IN THE AFTERNOON (WITH A
CHANCE OF THUNDER FOR SW COLORADO)...PERIODS OF LIGHT MOUNTAIN
SNOW WILL CONTINUE INTO THE EVENING.

MODEL SPREAD INCREASES WITH A SECONDARY DISURBANCE THAT IS MORE
DEPENDENT ON THE AMPLIFICATION OF UPSTREAM RIDGE. THE NEWEST 06Z
GFS DEPICTS A CLOSED LOW GETTING CARVED OUT OVER ERN ARIZONA AND
NEW MEXICO...FALLING SIMILARLY IN LINE WITH THE 00Z EURO MODEL.
THE NET RESULT FOR SATURDAY WOULD BE CLEARING ACROSS THE NORTH AND
ERN UTAH BUT LIGHT SNOW OR FLURRIES PERSIST OVER THE SAN JUAN
MOUNTAINS.

SUNDAY...RIDGE COVERS UTAH AND COLORADO FOR MOSTLY CLEAR CONDITIONS
WITH SEASONABLE TEMPS.

MONDAY AND TUESDAY...MEDIUM RANGE MODELS AGREE REASONABLY WELL THAT
THE RIDGE FLATTENS ON MONDAY WITH INCREASING WESTERLY FLOW. A
STREAM OF PACIFIC MOISTURE MOVES ACROSS THE INTERIOR WEST...REACHING
THE WESTERN SLOPE LATE MONDAY NIGHT OR TUESDAY...TARGETING THE
NORTH AND CENTRAL AREAS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 947 AM MST WED MAR 5 2014

CONDITIONS WILL REMAIN RELATIVELY UNCHANGED OVER THE NEXT 24 HOURS
AS A BREAK INBETWEEN WEATHER SYSTEMS SPANS THE TIMEFRAME. WINDS
WILL INCREASE SLIGHTLY IN THE AFTERNOON ACROSS CENTRAL UT AND CO
BUT DECREASE AFTER 00Z THIS EVENING. HIGH CLOUDS WILL BEGIN TO
INCREASE FROM WEST TO EAST THURSDAY MORNING AROUND 15Z THURS.
ISOLATED SHOWERS ARE POSSIBLE OVER THE UINTA MTNS IN NE UT DURING
THE MORNING HOURS...BUT NOT LIKELY UNTIL AFTER 18Z THURS.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...NONE.

UT...NONE.

&&

$$

SHORT TERM...15
LONG TERM...PF
AVIATION...JAM