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000
FXUS65 KGJT 150406
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1006 PM MDT TUE MAY 14 2013

.UPDATE...
ISSUED AT 1006 PM MDT TUE MAY 14 2013

THUNDERSTORMS HAVE ENDED BUT LIGHT SHOWERS STILL EXIST WITH
CONVECTIVE DEBRIS. THIS WILL BE SLOW TO DISSIPATE OVERNIGHT WITH
FORCING MECHANISM APPROACHING FROM THE WEST. PERHAPS SOME
SPRINKLES CONTINUE THROUGH THE NIGHT. BUT SHOWER INTENSITY HAS
DIMINISHED AND ANY SHOWERS GENERATE ONLY TRACE AMOUNTS.

&&

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 353 PM MDT TUE MAY 14 2013

CONVECTION IS MORE ACTIVE TODAY AS COMPERED TO YESTERDAY. THE
MORNING SOUNDING AT GRAND JUNCTION INDICATED BETTER
CAPE/INSTABILITY AND THE LACK OF A MID LEVEL CAP THAT WAS EVIDENT
ON TU E/S SOUNDING. STORMS ARE SLOW MOVING AND GENERALLY POP-AND-
DROP...AND ON THE WEAK SIDE. EXPECT CONVECTION TO AGAIN WIND DOWN
AS THE SUN SETS...HOWEVER TONIGHT THERE MAY BE A FEW NOCTURNAL
SHOWERS AS A SHORTWAVE APPROACHES FROM THE WEST. IN
ADDITION...MOISTURE HAS INCREASED A LITTLE THROUGH THE DAY...BUT
HAS REMAINED AT THE MID AND UPPER LEVELS. TEMPERATURES WILL AGAIN
BE VERY MILD TONIGHT.

WED`S SHORTWAVE WILL RESULT IN A BETTER COVERAGE OF SHOWERS AND
THUNDERSTORMS. MODELS ARE CONSISTENT IN BRINGING THE TROUGH AXIS
ACROSS DURING THE EVENING. THEREFORE INSTABILITY ASSOCIATED
WITH/AHEAD OF THE DISTURBANCE WILL BE ENHANCED BY DAYTIME HEATING.
MOISTURE WILL CONTINUE TO INCREASE THROUGH THE DAY...HOWEVER IT
WILL TAKE AWHILE FOR THE LOWER LEVELS TO SATURATE. AS A
RESULT...SHOWERS AND THUNDERSTORMS WILL REMAIN SCATTERED...AND
MAINLY OVER THE HIGHER TERRAIN. INCREASED CLOUD COVER WILL MEAN
HIGH TEMPERATURES WILL FALL A COUPLE DEGREES AS COMPARED TO
TODAY`S.

BY MIDNIGHT MOST SHOWER ACTIVITY WILL HAVE ENDED AS A DRIER AIR
MASS MOVES IN BEHIND THE SHORTWAVE. EXPECT LOW TEMPERATURES WILL
FALL A COUPLE DEGREES DUE TO THE DRIER AND MORE STABLE CONDITIONS.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 353 PM MDT TUE MAY 14 2013

THE UPPER HIGH THAT HAS BEEN OVER THE CENTRAL ROCKIES THE PAST FEW
DAYS LOOKS TO BE FORCED INTO THE PLAINS BY THURSDAY AFTERNOON. THIS
BREAK DOWN OF THE RIDGE OVER OUR AREA WILL LEAD TO A BACKING AND
INCREASE IN THE SOUTHERLY FLOW PRODUCED BY THE APPROACH OF AN
UPSTREAM TROF INTO THE WESTERN STATES. THETA SURFACES NEAR 315K
CONTINUE TO SHOW SOME MOISTURE TRANSPORT INTO OUR NORTHERN CWA
THURSDAY AFTERNOON BUT MAINLY AOA 500MB. WITH WEAKER FORCING AND A
LACK OF SURFACE FOCUS THE STORMS FORMATION SHOULD STILL FAVOR THE
TERRAIN THROUGH THE MID AFTERNOON...WITH SOME CHANCE OF ENOUGH
ORGANIZATION TO MOVE SOME ISOLATED STORMS INTO THE NORTHERN VALLEYS.
HIGHS WILL REMAIN WELL ABOVE NORMAL AND PERSISTENT TO THOSE SEEN THE
PAST FEW DAYS. THE MAIN CONCERN WILL CONTINUE TO BE FIRE WEATHER
RELATED AS BUFKIT SHOWS MIXING UP TO NEAR 500MB WHICH COULD PRODUCE
SOME GUSTY AFTERNOON WINDS IN THE DRY ATMOSPHERE.

THE DIURNALLY DRIVEN STORMS SHOULD DISSIPATE QUICKLY AS PWAT PLOTS
SHOW A STRONG PUSH OF DRY AIR THURSDAY NIGHT WHICH DOESN/T LOOK TO
RECOVER INTO SATURDAY WITH THE PUSH OF THE MAIN TROF. A WINDIER AND
WARM DAY CAN BE EXPECTED AGAIN FRIDAY AS THE WESTERN TROF MOVES INTO
THE GREAT BASIN...TIGHTENING THE PRESSURE GRADIENT. THIS SHOULD
BRING AN INCREASE TO THE GENERAL WINDS WITH GUSTS POTENTIAL
INCREASING AS WELL DUE TO THE STRONGER WINDS ALOFT. CONVECTION
REALLY LIMITED TO ISOLATED DUE TO THE LACK OF MOISTURE AND SHOULD BE
LIMITED TO THE HIGHEST TERRAIN. TEMPERATURE GUIDANCE LOOKS ON THE LOW
SIDE IN THIS PATTERN SO DID TWEAK ABOVE MOST AREAS.

THE MODELS AGREEMENT STILL SOMEWHAT SCATTERED COME FRIDAY NIGHT INTO
THE WEEKEND THOUGH THE END RESULT WILL GENERALLY BE UNSETTLED
WEATHER WITH AFTERNOON CONVECTION GOING INTO SUNDAY. THE GFS HAS
TAKEN A STRONGER TURN TODAY DROPPING THE MAIN ENERGY SOUTH TOWARD
THE 4 CORNERS FRI NITE INTO SATURDAY WHILE THE LESS AMPLIFIED EURO
CARRIES THIS ENERGY QUICKLY ACROSS THE NORTHERN CWA FRIDAY EVENING
AND OVERNIGHT. COOLER AIR WITH THE TROF PASSAGE ON SATURDAY SHOULD
LEAD TO UNSTABLE CONDITIONS AND SCATTERED CONVECTION WITH BOTH
SOLUTIONS GOING INTO THE DAY. MOISTURE RETURN WITH THIS TROF IS NOT
OVERLY IMPRESSIVE AND MUCH OF THE LIFT MAY BE USED TO RE-SATURATE THE
LOWER ATMOSPHERE. AS SUCH POPS STILL REMAIN IN THE CHANCE CATEGORY
WITH CONFIDENCE STILL SOMEWHAT LOW. MORE CERTAIN WILL BE THE DROP IN
TEMPERATURES BACK TO AND BELOW NORMAL SATURDAY INTO SUNDAY.

GOING INTO EARLY NEXT WEEK THE MED RANGE MODELS STILL REMAIN OUT OF
SYNC WITH RESPECT TO DROPPING ENERGY IN BEHIND THIS DEPARTING TROF.
THE EURO CONTINUES TO BE THE STRONGER OF THE SOLUTION WITH THE GFS
TRENDING THIS WAY SOMEWHAT TODAY. THIS MEANS MONDAY SHOULD REMAIN ON
THE COOLER SIDE WITH THE WARM UP BACK TO NORMAL OR ABOVE COMING
TOWARD MID WEEK. FORECAST POPS WILL REMAIN VERY LOW UNTIL BETTER
AGREEMENT INCREASES CONFIDENCE FOR THE LATE FORECAST PERIODS.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1006 PM MDT TUE MAY 14 2013

ISOLATED SHOWERS ENDING BY 06Z. DRY CONDITIONS ARE EXPECTED
THROUGH THE REMAINDER OF THE NIGHT AND THROUGH EARLY WED MORNING.
ISOLATED TO SCATTERED MAINLY MOUNTAIN SHOWERS AND THUNDERSTORMS
WILL AGAIN DEVELOP AFTER 18Z WEDNESDAY AND INTO WEDNESDAY EVENING.

VFR WILL DOMINATE IN THE LOWER ELEVATIONS THROUGHOUT THE PERIOD.
THE ONLY EXCEPTION WILL BE THE POSSIBILITY OF BRIEF MVFR
CONDITIONS AS A SHOWER OR THUNDERSTORM MOVES OFF THE HIGHER
TERRAIN UNTIL AROUND 03Z THIS EVENING...AND AGAIN AFTER 18Z WED.

&&

.FIRE WEATHER...(TONIGHT THROUGH MONDAY)
ISSUED AT 353 PM MDT TUE MAY 14 2013

ABOVE NORMAL WARMTH AND MOSTLY DRY CONDITIONS ARE EXPECTED DURING
THE UPCOMING WEEK WHICH COULD QUICKLY RAISE FIRE WEATHER CONCERNS.
MUCH WILL BE DEPENDENT ON FUEL CONDITIONS...AND LAND AGENCIES ARE
ENCOURAGED TO KEEP THEIR FUELS STATUS UPDATED.

THE FOCUS FOR ISOLATED CRITICAL FIRE WEATHER CONDITIONS WILL
BE IN SOUTHWEST COLORADO ON WEDNESDAY BUT CRITICAL FIRE WEATHER
CONDITIONS WILL IN PLACE OVER MOST OF THESE AREAS DUE TO GREEN
UP. STRONGER AND MORE WIDESPREAD WIND WITH LOW HUMIDITY IS
ANTICIPATED THURSDAY AND ESPECIALLY FRIDAY AHEAD OF ANOTHER
PACIFIC SYSTEM MOVING INLAND. A FIRE WEATHER WATCH HAS BEEN ISSUED
FOR THE ZONE 203 IN COLORADO BELOW 8000 FEET WITH THE MAIN AREA OF
CONCERN WITH GUSTY WINDS POSSIBLE ALONG THE I-70 CORRIDOR.

ISOLATED TO SCATTERED DIURNAL SHOWERS AND THUNDERSTORMS ARE
EXPECTED MAINLY OVER THE MTNS ON MOST DAYS THIS WEEK. THE STORMS
SHOULD BE STORMS WILL BE MAINLY HIGH-BASED AND LIKELY TO PRODUCE
MORE WIND THAN RAIN.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...FIRE WEATHER WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY
     EVENING FOR COZ203.

UT...NONE.
&&

$$

UPDATE...PF
SHORT TERM...EH
LONG TERM...15
AVIATION...PF
FIRE WEATHER...15