FXUS65 KGJT 082101
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
301 PM MDT TUE JUL 8 2008

.SHORT TERM...TONIGHT THROUGH THURSDAY...
WIDELY SCATTERED THUNDERSTORMS FIRED OVER THE NORTHERN...CENTRAL AND
SOUTHERN MOUNTAINS OF COLORADO...AS WELL AS THE ABAJO MOUNTAINS IN
SOUTHEAST UTAH EARLY THIS AFTERNOON. MEANWHILE...THE NORTHWEST HALF
OF THE CWFA WAS DRY AND STABLE.

FALLING DEWPOINTS ACROSS THE NORTHWEST PROVIDED SOME EVIDENCE OF
DRYING TREND POINTED TO IN EARLIER FORECASTS. MEANWHILE...RESIDUAL
MOISTURE AND DIURNAL HEATING RESPONSIBLE FOR PULSE STORMS OVER THE
MOUNTAINS ALONG THE DIVIDE AND IN SOUTHEAST UTAH.

BROAD EAST-WEST ORIENTED RIDGE OVER THE WESTERN U.S. WILL CONTINUE
TO SHUNT DEEP SUBTROPICAL MOISTURE TO THE EAST OVER THE NEXT FEW
DAYS BRINGING A CONTINUED PATTERN OF ISOLATED AFTERNOON/EVENING TSTMS
ALONG THE DIVIDE THROUGH THURSDAY. AREAL COVERAGE WILL SLOWLY
DECREASE EACH DAY AS MOISTURE WANES. CONVERSELY...TEMPERATURES WILL
RISE IN RESPONSE TO INCREASED INSOLATION WHICH MOS GUIDANCE APPEARED
TO HANDLE WELL.

.LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...
LONG TERM MODELS REMAIN IN VERY GOOD AGREEMENT...ESPECIALLY FOR THE
WARM SEASON. A DRY AND WARM WORK-WEEK GIVES WAY TO WHAT MAY BE A
SIGNIFICANT MONSOONAL BURST BY SUNDAY INTO MONDAY.

THURSDAY NIGHT-FRIDAY...NW FLOW REMAINS OVER THE AREA KEEPING DEEP
SUBTROPICAL MOISTURE TO THE SOUTH OF THE FOUR CORNERS. WE ARE TALKING
DEEP MOISTURE...WITH PRECIPITABLE WATER (PW) VALUES OF 2.3 INCHES IN
THE YUMA AREA. THETA-E RIDGE REMAINS IN PLACE ALONG THE SOUTHERN
CONTINENTAL DIVIDE FOR THE BEST CHANCE OF THUNDERSHOWERS IN MEAGER
MOISTURE. FRIDAY AFTERNOON TEMPERATURES WILL RIVAL THE 4TH OF
JULY FOR THE WARMEST DAY OF THE YEAR THUS FAR.

FRIDAY NIGHT...THE LEADING EDGE OF THIS MOISTURE BEGINS TO MOVE INTO
THE SAN JUAN REGION. SATURDAY AFTERNOON PW VALUES ARE UP TO 0.75 INCH
ACROSS MUCH OF EASTERN UTAH WITH 1 INCH VALUES AT THE FOUR CORNERS.
BEST UPPER FORCING REMAINS IN AZ BUT THE SOUTHERN MTNS WILL
INITIATE INCREASED THUNDERSTORM COVERAGE THAT WILL MOVE OVER THE
SOUTHERN VALLEYS LATE IN THE DAY. MOISTURE ADVECTION CONTINUES
SATURDAY NIGHT THAT MAY KEEP ISOLATED STORMS GOING OVERNIGHT.

SUNDAY-MONDAY NIGHT...PW VALUES NOW PROGGED OVER 0.8 INCHES FOR ALL
BUT THE PARK RANGE...AND UP TO AROUND 1 INCH ON MONDAY. IN ADDITION
BOTH THE GFS AND WRF ROTATE A PERSISTENT CENTER OF UPPER FORCING SEEN
IN THE Q AND 2-3 DIVERGENCE FIELDS ALONG THE UTAH-COLORADO BORDER.
THEREFORE HAVE INCREASED POPS AGAIN FOR THESE PERIODS WITH NOCTURNAL
STORMS A GOOD POSSIBILITY. THERE IS THE POTENTIAL FOR LOCALLY HEAVY
SHOWERS FAVORING THE SOUTHERN ZONES. DIURNAL TEMPERATURE RANGE
LIMITED ON BOTH ENDS.

TUESDAY...A DRIER WEST FLOW BEGINS TO ERODE THE SUBTROPICAL
MOISTURE...BUT WETTING RAINS WILL STILL FAVOR THE EASTERN ZONES.

&&

.AVIATION...VFR CONDITIONS WILL PREVAIL TONIGHT...EXCEPT OVER THE SAN
JUAN MOUNTAINS AND THE CENTRAL COLORADO MOUNTAINS SOUTH OF I-70 WHERE
ISOLATED EARLY EVENING THUNDERSTORMS WILL CAUSE LOCAL MVFR CIGS.

&&

.HYDROLOGY...
MOUNTAIN SNOWPACK CONTINUES TO DWINDLE AND RUNOFF WILL GRADUALLY
DECREASE RESULTING IN A SLOW LOWERING OF RIVER AND STREAM FLOWS
THROUGH THIS WEEK. ALTHOUGH WATER LEVELS ARE DECREASING...FLOWS
REMAIN COLD...SWIFT...AND TURBULENT. CAUTION IS URGED AROUND
RIVERS AND STREAMS.

&&

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

$$

SHORT TERM.....NL
LONG TERM......JOE+ELH
AVIATION.......NL
HYDROLOGY......TGJT

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