Area Forecast Discussion
Issued by NWS Grand Junction, CO

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FXUS65 KGJT 091649
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1049 AM MDT WED APR 9 2014

.UPDATE...
ISSUED AT 1046 AM MDT WED APR 9 2014

HIGH PRESSURE REMAINS AT THE SURFACE BUT WILL BE WEAKENING AS AN
UPPER TROUGH MOVING EAST ACROSS SOUTHERN CANADA DRAGS A WEAK COOL
FRONT TOWARD OUR AREA. SATELLITE SHOWING A FAIRLY OPAQUE SHIELD OF
HIGH CLOUDS MOVING ACROSS NV/UT...AND HAVE BUMPED UP THE AMOUNT OF
CLOUDS FOR OUR AREA THIS AFTERNOON. THIS MAY SLOW THE DEVELOPMENT OF
GUSTY WINDS FROM MIXING BUT STILL EXPECTING THEM TO OCCUR. THE RED
FLAG WARNING FOR PORTIONS OF SW CO REMAINS IN EFFECT THIS AFTERNOON
THROUGH EARLY EVENING.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 310 AM MDT WED APR 9 2014

THE BROAD UPPER HIGH REMAINS CENTERED IN NW MEXICO BUT IS
FLATTENED TODAY AS A MILD BUT ENERGETIC SYSTEM WORKS THROUGH THE
CANADIAN ROCKIES. THE ASSOCIATED DISORGANIZED POLAR FRONT JET
SAGS INTO WY THIS AFTERNOON AND EVENING PRODUCING A MILD
CONVERGENT-DIVERGENT COUPLET ALONG THE CO-WY BORDER. ISOLATED
CONVECTIVE SHOWERS FORM OVER THE NORTHERN MTNS THIS AFTERNOON AND
EVENING. WITH 700MB TEMPS AT +5C THIS AFTERNOON THESE SHOWERS WILL
BE ALL RAIN.

FOR THE REMAINDER OF THE FORECAST AREA...THE BREAKDOWN OF THE
UPPER LEVEL RIDGE BRINGS WARM AND BREEZY CONDITIONS. 700-600MB
LAYER WEST WINDS INCREASE TO 25KTS THIS AFTERNOON. THE WEAK
SUBSIDENCE INVERSION AT 12KFT YESTERDAY WILL BE ERODED TODAY
ALLOWING DEEPER MIXING. AFTERNOON TEMPERATURES CLIMB TO 10-15
DEGREES ABOVE NORMAL. THE SOUTHERN AND CENTRAL ZONES ALSO REMAIN
VERY DRY RAISING FIRE WEATHER CONCERNS...SEE DISCUSSION BELOW.

UNDER STREAMING HIGH CLOUDS TEMPERATURES STAY VERY MILD TONIGHT.
SHOWERS OVER THE NORTH MAY TURN TO SNOW OVER THE HIGHEST
ELEVATIONS OF THE UINTAS AND ZIRKELS. LITTLE CHANGE EXPECTED ON
THURSDAY WITH CONTINUED WARM AND BREEZY TO WINDY CONDITIONS ACROSS
THE FORECAST AREA AND LIGHT CONVECTIVE SHOWERS ACROSS THE NORTH.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 310 AM MDT WED APR 9 2014

VERY LITTLE CHANGE TO FORECAST THINKING IN REGARDS TO LONG-TERM
FORECAST. SOME VERY ISOLATED SHOWERS ARE POSSIBLE THURSDAY NIGHT IN
RESPONSE TO A WEAK WAVE THAT WILL MOVE ACROSS THE AREA. WITH LITTLE
MOISTURE TO WORK WITH AND VERY LIMITED DYNAMICAL SUPPORT...MEAGER
AMOUNTS ARE EXPECTED AT BEST.

NO PRECIP EXPECTED FRIDAY AS A CLOSED LOW APPROACHES FROM THE WEST
AND A TROUGH APPROACHES FROM THE NW. THE EC AND GFS CONTINUE TO
DISAGREE ON EVOLUTION OF THESE TWO SYSTEMS AS EC FAVORS A DEEPER
TROUGH TO OUR WEST WHILE GFS KEEPS IT FURTHER EAST...LITTLE
CHANGE FROM PREVIOUS MODEL RUNS. INCREASING POPS FROM SATURDAY
AFTN ONWARDS LOOKS GOOD ATTM WITH THE BEST CHANCES FOR PRECIP
LOOKING TO BE SUNDAY.

BY MONDAY...THE CLOSED LOW AND TROUGH WILL HAVE PHASED CREATING A
FAIRLY STRONG COLD FRONT THAT WILL MOVE ACROSS THE MIDWEST ALLOWING
A TRANSITORY RIDGE TO MOVE ACROSS OUR CWA. THIS WILL BE SHORT-LIVED
THOUGH AS ANOTHER AREA OF LOW PRESSURE MOVES ALONG THE CANADIAN/US
BORDER TRAILING A COLD FRONT BEHIND IT AS IT DOES SO. PRE-FRONTAL
PRECIP LOOKS TO START TUESDAY AFTN AND INCREASE AS THE COLD FRONT
APPROACHES LATER ON THAT EVENING AND BEYOND.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1046 AM MDT WED APR 9 2014

VFR CONDITIONS EXPECTED AT ALL TAF SITES THROUGH 18Z THU. LOCAL WIND
GUSTS TO 25 KNOTS CAN BE EXPECTED THIS AFTERNOON AND EVENING
PRODUCING LIGHT TO MODERATE TURBULENCE ESPECIALLY ALONG AND EAST OF
HIGHER TERRAIN. ISOLATED SHOWERS OVER THE NORTHERN MTNS MAY PRODUCE
LOCAL BRIEF OBSCURATIONS THIS AFTERNOON THROUGH THU.

&&

.FIRE WEATHER...
ISSUED AT 310 AM MDT WED APR 9 2014

FUELS ARE CRITICAL IN SW CO SPECIFICALLY IN ZONE 290 BELOW 9000
FT...AND ZONE 207 BELOW 7500 FEET. RH VALUES WILL AGAIN FALL INTO
THE TEENS WEDNESDAY THROUGH FRIDAY AFTERNOONS. THE STRONGEST
WINDS WILL BE FURTHER NORTH WHERE FUELS ARE NOT CRITICAL. THE
LATEST MODELS STILL SUPPORTS DEEP AFTERNOON MIXING PRODUCING WIND
GUSTS OF 25 MPH ACROSS THE VALLEYS OF SW CO. A RED FLAG IS VALID
1PM TO 7PM FOR GUSTY WINDS...LOW RH...DRY FUELS...AND HAINES INDEX
OF 6.

VALLEY WINDS WILL DIE OFF QUICKLY TOWARDS SUNSET WHILE SLOPES
WILL CONTINUE TO SEE MIXING GRADIENT WINDS. RH RECOVERY TONIGHT
WILL BE POOR. THURSDAY THE AFTERNOON WIND GUSTS WILL AGAIN BE
CLOSE TO RED FLAG CRITERIA. A FIRE WEATHER WATCH IS IN EFFECT FOR
THURSDAY 1 PM TO 7 PM.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...RED FLAG WARNING UNTIL 7 PM MDT THIS EVENING FOR COZ205-207.

     FIRE WEATHER WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY
     EVENING FOR COZ205-207.

UT...NONE.
&&

$$

UPDATE...JAD
SHORT TERM...JOE
LONG TERM...TGR
AVIATION...TGJT
FIRE WEATHER...JOE



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