Area Forecast Discussion
Issued by NWS Grand Junction, CO

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS65 KGJT 302303
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
503 PM MDT SAT AUG 30 2014

.SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT)
ISSUED AT 226 PM MDT SAT AUG 30 2014

NICE BAROCLINIC LEAF SHOWING UP ON SATELLITE IMAGERY FROM MT TO
UT. EASTERN UT AND WESTERN CO WILL REMAIN UNSETTLED IN ADVANCE OF
THE LONGWAVE TROUGH AXIS MOVING EAST ACROSS THE GREAT BASIN/NRN
ROCKIES TONIGHT...THEN ACROSS CO SUNDAY. PRECIP WATER VALUES WILL
PEAK TONIGHT AROUND 0.80 INCH. DIFFERENTIAL VORTICITY ADVECTION
AND QG FORCING IN PLACE OVER THE AREA TONIGHT. LATE TONIGHT INTO
SUN MORNING 100 KT UPPER JET WILL PROVIDE THE ATMOSPHERE OVER NORTHEAST
UT AND NRN CO WITH ADDITIONAL LIFT. CONVECTION ALREADY FIRING OVER
THE HIGHER TERRAIN THIS AFTERNOON AND EXPECT IT TO REMAIN ISOLATED
TO SCATTERED...WITH GREATEST COVERAGE ACROSS THE NORTHERN HALF OF
THE AREA. WILL SEE SOME DECREASE IN COVERAGE OVERNIGHT...BUT NOT A
TOTAL CESSATION. GREATEST CHANCES SUNDAY WILL LIKELY MAX OUT
AROUND MIDDAY WITH SUBSIDENCE AND DRYING IN THE WAKE OF THE UPPER
TROUGH HELPING TO DIMINISH COVERAGE LATER IN THE DAY. WITH
STEERING WINDS AND SPEED SHEAR RATHER STRONG...EXPECT STORMS TO BE
MAINTAIN THEMSELVES AND MOVE ALONG AT A PRETTY GOOD CLIP.
THUNDERSTORMS WILL HAVE TO BE WATCHED FOR STRONG GUST POTENTIAL
THOUGH THE OVERALL WEAK CAPE WILL LIMIT POTENTIAL FOR SEVERE
GUSTS.

.LONG TERM...(LABOR DAY THROUGH SATURDAY)
ISSUED AT 226 PM MDT SAT AUG 30 2014

MONDAY BEGINS WITH THE UPPER JET ALONG THE CO/WY BORDER. THE JET
QUICKLY SHIFTS EAST AS A WEAK IMPULSE PASSES TO OUR NORTH EARLY
IN THE DAY. WHILE THE POSITION OF THE UPPER JET AND THE WEAK
DISTURBANCE WILL KEEP A MODERATE WEST-NORTHWEST FLOW OVER THE
NORTH THROUGH THE DAY...SURFACE WINDS WILL BE LIGHTER THAN THIS
WEEKEND`S. BUT WE WILL STILL FEEL SOME MODERATE BREEZES OVER THE
NORTH. THE AIR MASS DRIES AS THE FLOW BECOMES MORE NORTHWEST
DURING THE AFTERNOON...AND COMBINED WITH WARMING ALOFT...
CONVECTION WILL BE VERY LIMITED TO NON-EXISTENT.

THE SUB-TROPICAL RIDGE BUILDS DURING THE NEXT COUPLE OF DAYS WITH
A DRY WESTERLY FLOW OVER OUR FORECAST AREA THROUGH MIDWEEK. BY
THU THE FLOW BECOMES SOUTHWEST AS THE NEXT LOW PRESSURE TROUGH
DEVELOPS OVER THE WEST COAST. MODELS INDICATE THAT ANY EJECTING
SHORTWAVES WILL BE TOO FAR NORTH TO AFFECT OUR CWA. THE SOUTHWEST
FLOW HOWEVER WILL RESULT A SLOW INCREASE IN MOISTURE AS THE DOOR
IS OPENED TO THE SOUTH. LATE IN THE PERIOD...MODEL CONSISTENCY
DROPS. THE GFS KEEPS THE TROUGH TO OUR WEST THROUGH SATURDAY.
WHILE THE ECMWF SHOWS THE MAIN TROUGH GREATLY WEAKENING BY SAT AS
MORE ENERGY WILL HAVE SPLIT OFF PIECEMEAL DURING THE SECOND HALF
OF THE WORK WEEK.

MON MORNING PROMISES TO BE RELATIVELY COOL...WITH THE SOME OF THE
HIGHER AND NORTHERN VALLEYS DIPPING INTO THE 30S. TEMPERATURES
WILL THEN WARM TO NORMAL OR ABOVE BY MIDWEEK.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 503 PM MDT SAT AUG 30 2014

A WEAK DISTURBANCE WILL CONTINUE TO BRING SHOWERS AND
THUNDERSTORMS TO AREAS EAST OF KDWX TO KDRO LINE THROUGH 03Z.
THESE STORMS WILL BE CAPABLE OF GENERATING WIND GUSTS TO 40 MPH
ALONG WITH BRIEF HEAVY RAIN. KASE AND KRIL HAVE A GOOD CHANCE OF
EXPERIENCING SHOWERS...THOUGH ITS UNLIKELY THAT THE FLIGHT
CATEGORY WILL DROP BELOW VFR. EXPECT DRY AND QUIET CONDITIONS FOR
ALL BUT THE NORTHERNMOST PORTION OF THE FORECAST AREA FROM 06Z TO
18Z/SUNDAY. ANOTHER FAST MOVING DISTURBANCE WILL GENERATE
ADDITIONAL SHOWERS ALONG THE SOUTHERN WYOMING BORDER AREA LATE
TONIGHT. THIS ACTIVITY WILL MOVE INTO THE NORTHERN COLORADO
MOUNTAINS FROM 12Z TO 18Z. DAYTIME HEATING COMBINED WITH THIS
DISTURBANCE WILL CAUSE STORMS TO SPREAD INTO THE CENTRAL MOUNTAINS
AND SURROUNDING AREAS AS WELL.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...NONE.
UT...NONE.

&&

$$

SHORT TERM...BEN
LONG TERM...EH
AVIATION...NL



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.