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000
FXUS65 KGJT 251753
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1153 AM MDT FRI JUL 25 2014

.UPDATE...
ISSUED AT 1024 AM MDT FRI JUL 25 2014

MADE MINOR ADJUSTMENTS TO POP FORECAST GRIDS FOR INCREASING CLOUD
TOPS OVER EAST CENTRAL UTAH. EXPECTING MORE ACTIVITY IN NORTHERN
COLORADO TODAY THAN YESTERDAY...BUT STILL EXPECTING THE SAN JUANS
TO BE BUSY THIS AFTERNOON DUE TO DAYTIME HEATING AND INSTABILITY.

&&

.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 415 AM MDT FRI JUL 25 2014

MONSOONAL MOISTURE CONTINUES TO STREAM OVER THE FORECAST AREA
TODAY. PRECIPITABLE WATER REMAINS HIGH WITH VALUES EXCEEDING AN
INCH IN THE DESERT VALLEYS. ISOLATED NOCTURNAL STORMS PERSIST IN
THIS ENVIRONMENTAL...NO EXCEPTION THIS MORNING WITH AS A CLUSTER
OF CELLS MOVED ACROSS MOFFAT AND ROUTT COUNTY. A SMALLER CLUSTER
OF CELLS DEVELOPED OVER GRAND COUNTY IN UTAH AND CURRENTLY MOVING
INTO MESA COUNTY. RADAR IS PICKING UP SOME RETURNS ACROSS THE FAR
SOUTH...BUT NO LIGHTNING HAS BEEN OBSERVED.

MORE SHOWERS AND THUNDER IS EXPECTED TODAY WITH CELLS MOVING FROM
WSW TO ENE. CELL MOVEMENT IS FAST ENOUGH THAT THE CHANCE FOR ANY
PROLONGED HEAVY RAIN IS QUITE SMALL. HOWEVER THE STRONGEST CELLS
MAY MANAGE HEAVY RAINS TO CAUSE LOCALIZED MUD DEBRIS FLOWS AND
ROCK SLIDES IN THE STEEPEST TERRAIN.

ALONG THE WYOMING BORDER...THE THREAT OF CONVECTIVE STORMS DIMINISHES
AS A TRAILING SHORT WAVE ADVECTS DRIER MORE STABLE AIR FROM THE
WEST.

MOST CONVECTION WILL CONTINUE INTO THE EVENING HOURS BUT BY AROUND
9PM...STORMS AND SHOWERS WILL SLOWLY START DYING OFF. EVEN SO...A
FEW STRAY SHOWERS AND WEAK STORMS WILL PERSIST MUCH LIKE THURSDAY
NIGHT. AS HAS BEEN THE CASE LATELY...AREAS SOUTH OF I-70 REMAIN FAVORED
ESPECIALLY THE SAN JUANS. THE LOCATION OF THE HIGH PRESSURE ON
SATURDAY APPEARS TO PUSH MONSOONAL MOISTURE MORE INTO UTAH WHICH
ALSO SHOWS UP WITH FORECAST PWATS BEING A BIT LOWER THAN FRIDAY.
HOWEVER...PLENTY OF MOISTURE WILL REMAIN IN THE ATMOSPHERE FOR
ANOTHER ROUND OF CONVECTION TO FIRE WITH THE ROAN/TAVAPUTS...BOOKCLIFFS
AND AREAS SOUTH FAVORED YET AGAIN.

.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 415 AM MDT FRI JUL 25 2014

THE AREA OF HIGH PRESSURE WILL CONTINUE TO WOBBLE OVER SRN CO AND
NRN NM WITH MODELS HINTING AT A MORE DEFINITE PUSH OF MONSOONAL
MOISTURE TO OUR WEST. PWATS LOOK TO DROP TO ABOUT .8 INCHES
WHICH IS STILL ABOUT 120 PERCENT OF NORMAL. THAT BEING
SAID...MORE CONVECTION ON THE WAY THOUGH COVERAGE WILL BE LESS
THAN SEEN THE LAST FEW DAYS...FAVORING THE HIGHER TERRAIN.

MONDAY THROUGH THURSDAY...NO SIGNIFICANT PATTERN CHANGE AS THE
DESERT SOUTHWEST MONSOON STAYS ACTIVE. MEDIUM RANGE MODEL DO SHOW
EASTERLY WAVES THAT ROTATE AROUND THE HIGH PRESSURE CENTER...BUT
DIFFICULT TO FINE TUNE THESE DETAILS SEVERAL DAYS IN ADVANCE. THE
BROADBRUSH APPROACH IS THE BEST FORECAST...THIS CURRENT PATTERN
FAVORS AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS WITH LOCALIZED
HEAVY RAINS AND ISOLATED NOCTURNAL STORMS. AFTERNOON TEMPS WILL BE
NEAR AVERAGE...BUT NIGHTS WILL BE MILD/WARM AS NOCTURNAL BREEZES
PREVENT ANY PRONOUNCED COOLING.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1024 AM MDT FRI JUL 25 2014

ALL TAF SITES CAN EXPECT SHOWERS AND/OR THUNDERSTORMS IN THE
VICINITY THROUGH 04Z TONIGHT. THE MAIN THREAT FROM THUNDERSTORMS
ARE EXPECTED TO BE BRIEF HEAVY RAIN AND ERRATIC WIND GUSTS 30-40
KTS...WITH MVFR CIGS AND MOUNTAIN OBSCURATIONS POSSIBLE FROM
PASSING +SHRA/+TSRA. DECREASING -SHRA/-TSRA ARE EXPECTED AFTER 04Z
TONIGHT. AFTER A MORNING LULL...ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS WILL DEVELOP AFTER 18Z SAT AFTERNOON.

&&

.FIRE WEATHER...
ISSUED AT 415 AM MDT FRI JUL 25 2014

WINDS AND RH VALUES MAY BECOME NEAR CRITICAL FOR A FEW HOURS
THIS AFTERNOON IN THE LITTLE SNAKE FORECAST AREA OF NORTHWESTERN
COLORADO. AN UPPER LOW WILL TRACK OVER THE NORTHERN ROCKIES WILL
TIGHTEN THE UPPER GRADIENT AND BRING DRIER AIR OVER NORTHWESTERN
COLORADO. THE LOW WILL MOVE INTO THE NORTHERN PLAINS AND WINDS
WILL RELAX AGAIN ON SATURDAY.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&

$$

UPDATE...JAM
SHORT TERM...PF/TGR
LONG TERM...TGR/PF
AVIATION...JAM
FIRE WEATHER...AS