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000
FXUS65 KGJT 210505
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1105 PM MDT WED AUG 20 2014

.UPDATE...
ISSUED AT 846 PM MDT WED AUG 20 2014

SOME SHOWERS AND STORMS CONTINUING THIS EVENING AS A WEAK WAVE
MOVES OVERHEAD ESPECIALLY FOR NORTHERN AREAS. PLENTY OF CONVECTION
ALSO CONTINUES SOUTH OF SALT LAKE CITY AND IS MOVING TO THE
EAST-NORTHEAST. IF THE CONVECTION HOLDS TOGETHER...WE CAN EXPECT
TO SEE A BIT MORE PRECIPITATION FOR THE NEXT COUPLE OF HOURS SO
BUMPED UP POPS TO ACCOUNT FOR THIS POSSIBILITY NORTH OF I-70. THE
REST OF THE CWA MAY SEE A PASSING SHOWER BUT NOT EXPECTING MUCH
QPF.

&&

.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 308 PM MDT WED AUG 20 2014

DRIER AIR IS ENTRAINING INTO THE AREA FROM THE SOUTHWEST AND THIS
APPEARS TO BE HELPING HOLD DOWN VERTICAL DEVELOPMENT OVER CENTRAL
AND SW CO AND SE UT. A WEAK UPPER TROUGH IS DRAGGING ACROSS NW CO
AND THIS WILL CONTINUE TO PROVIDE THE EXTRA LIFT NEEDED FOR SINGLE
CELL THUNDERSTORMS TO FORM...MAINLY OVER HIGHER TERRAIN. STILL...
WITH A FEW MORE HOURS OF SUN AVAILABLE THE REST OF THE
AFTERNOON...SCATTERED SHOWERS AND TSTMS SHOULD DEVELOP OVER THE
MOUNTAINS OF CENTRAL CO AFTER ABOUT 22Z AND CONTINUE UNTIL
SUNSET...WITH ISOLATED DEVELOPMENT ELSEWHERE.

CONTINUED DRYING IS EXPECTED LATE TONIGHT THROUGH THU NGT WITH
LOWER POPS AND CLOUD COVER EXPECTED. THE INTERESTING THING TO
WATCH WILL BE THE INTERACTION OF MOISTURE FROM TROPICAL STORM
LOWELL IN THE ERN PACIFIC WITH THE APPROACH TROUGH FROM THE NW.
SOME MOISTURE IS BEING DRAWN NORTH OVER BAJA CALIFORNIA AND IS
DRAWING A BEAD ON THE FOUR CORNERS. BY THU NIGHT THE NAM12
COMBINES THIS MOISTURE WITH THE NEXT MONSOONAL SURGE COMING UP
FROM NW MEXICO.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 308 PM MDT WED AUG 20 2014

TS LOWELL IS FORECAST TO REMAIN NEARLY STATIONARY OFF OF THE
COAST OF BAJA CALIFORNIA AND CONTINUE TO FEED SOME MID TO HIGH
LEVEL MOISTURE INTO THE FOUR CORNERS REGION. ANOTHER CLOSED LOW
IS FORECAST TO DROP INTO THE PACIFIC NORTHWEST AS AN OFFSHOOT OF
THE HIGH AMPLITUDE WESTERN US TROUGH IN PLACE. AS THIS CLOSED LOW
DIVES INTO THE INTERMOUNTAIN WEST THIS WEEKEND...TS LOWELL WILL
SLOWLY SHIFT TO THE WEST AND HAVE LESS OF AN INFLUENCE ON MOISTURE
IN THE REGION. FRIDAY NIGHT...THE APPROACHING LONGWAVE TROUGH WILL
BRING THE COUPLING OF A BAROCLINIC ZONE AND UPPER LEVEL JET WHICH
SHOULD BRING NOCTURNAL ACTIVITY TO THE NORTHERN PART OF THE GJT
CWA. QG FORCING IS MODERATE WITH THIS BOUNDARY. EXPECTING RAIN
AND STORMS FRIDAY NIGHT THROUGH SATURDAY MORNING ACROSS NORTHERN
UTAH AND COLORADO...WITH SCATTERED PRECIPITATION OVER THE
MOUNTAINS ELSEWHERE.

THIS TROUGHY PATTERN WILL CONTINUE THROUGH EARLY NEXT WEEK...WITH
MONDAY NIGHT/TUESDAY LOOKING LIKE THE NEXT SOMEWHAT ACTIVE
WEATHER DAY AFTER FRIDAY NIGHT/SATURDAY. THERE IS CONSIDERABLY
GOOD AGREEMENT BETWEEN THE GFS AND EC IN THE LONG TERM...AND THE
CURRENT MODELS SUGGEST HIGH PRESSURE MAY ARRIVE BY THE END OF NEXT
WEEK.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1058 PM MDT WED AUG 20 2014

PRECIP HAS JUST ABOUT ENDED ACROSS THE CWA WITH VFR CONDITIONS
BECOMING PREDOMINANT. MORE STORMS AND SHOWERS EXPECTED AGAIN
TOMORROW BUT STILL THINKING COVERAGE WILL BE LESS WITH ONLY
KASE...KEGE AND KTEX MAYBE SEEING SOME PRECIP. VCSH FOR KASE AND
KEGE WITH VCTS FOR KTEX IN THE AFTERNOON LOOKS A SAFE BET FOR NOW
WITH LOW TO MEDIUM CONFIDENCE. REMAINING TAF SITES SHOULD REMAIN
VFR WITH SOME HIGH CIGS MOVING IN DURING THE AFTERNOON.

&&

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

$$

UPDATE...TGR
SHORT TERM...CC
LONG TERM...JAM
AVIATION...TGR




000
FXUS65 KGJT 210505
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1105 PM MDT WED AUG 20 2014

.UPDATE...
ISSUED AT 846 PM MDT WED AUG 20 2014

SOME SHOWERS AND STORMS CONTINUING THIS EVENING AS A WEAK WAVE
MOVES OVERHEAD ESPECIALLY FOR NORTHERN AREAS. PLENTY OF CONVECTION
ALSO CONTINUES SOUTH OF SALT LAKE CITY AND IS MOVING TO THE
EAST-NORTHEAST. IF THE CONVECTION HOLDS TOGETHER...WE CAN EXPECT
TO SEE A BIT MORE PRECIPITATION FOR THE NEXT COUPLE OF HOURS SO
BUMPED UP POPS TO ACCOUNT FOR THIS POSSIBILITY NORTH OF I-70. THE
REST OF THE CWA MAY SEE A PASSING SHOWER BUT NOT EXPECTING MUCH
QPF.

&&

.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 308 PM MDT WED AUG 20 2014

DRIER AIR IS ENTRAINING INTO THE AREA FROM THE SOUTHWEST AND THIS
APPEARS TO BE HELPING HOLD DOWN VERTICAL DEVELOPMENT OVER CENTRAL
AND SW CO AND SE UT. A WEAK UPPER TROUGH IS DRAGGING ACROSS NW CO
AND THIS WILL CONTINUE TO PROVIDE THE EXTRA LIFT NEEDED FOR SINGLE
CELL THUNDERSTORMS TO FORM...MAINLY OVER HIGHER TERRAIN. STILL...
WITH A FEW MORE HOURS OF SUN AVAILABLE THE REST OF THE
AFTERNOON...SCATTERED SHOWERS AND TSTMS SHOULD DEVELOP OVER THE
MOUNTAINS OF CENTRAL CO AFTER ABOUT 22Z AND CONTINUE UNTIL
SUNSET...WITH ISOLATED DEVELOPMENT ELSEWHERE.

CONTINUED DRYING IS EXPECTED LATE TONIGHT THROUGH THU NGT WITH
LOWER POPS AND CLOUD COVER EXPECTED. THE INTERESTING THING TO
WATCH WILL BE THE INTERACTION OF MOISTURE FROM TROPICAL STORM
LOWELL IN THE ERN PACIFIC WITH THE APPROACH TROUGH FROM THE NW.
SOME MOISTURE IS BEING DRAWN NORTH OVER BAJA CALIFORNIA AND IS
DRAWING A BEAD ON THE FOUR CORNERS. BY THU NIGHT THE NAM12
COMBINES THIS MOISTURE WITH THE NEXT MONSOONAL SURGE COMING UP
FROM NW MEXICO.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 308 PM MDT WED AUG 20 2014

TS LOWELL IS FORECAST TO REMAIN NEARLY STATIONARY OFF OF THE
COAST OF BAJA CALIFORNIA AND CONTINUE TO FEED SOME MID TO HIGH
LEVEL MOISTURE INTO THE FOUR CORNERS REGION. ANOTHER CLOSED LOW
IS FORECAST TO DROP INTO THE PACIFIC NORTHWEST AS AN OFFSHOOT OF
THE HIGH AMPLITUDE WESTERN US TROUGH IN PLACE. AS THIS CLOSED LOW
DIVES INTO THE INTERMOUNTAIN WEST THIS WEEKEND...TS LOWELL WILL
SLOWLY SHIFT TO THE WEST AND HAVE LESS OF AN INFLUENCE ON MOISTURE
IN THE REGION. FRIDAY NIGHT...THE APPROACHING LONGWAVE TROUGH WILL
BRING THE COUPLING OF A BAROCLINIC ZONE AND UPPER LEVEL JET WHICH
SHOULD BRING NOCTURNAL ACTIVITY TO THE NORTHERN PART OF THE GJT
CWA. QG FORCING IS MODERATE WITH THIS BOUNDARY. EXPECTING RAIN
AND STORMS FRIDAY NIGHT THROUGH SATURDAY MORNING ACROSS NORTHERN
UTAH AND COLORADO...WITH SCATTERED PRECIPITATION OVER THE
MOUNTAINS ELSEWHERE.

THIS TROUGHY PATTERN WILL CONTINUE THROUGH EARLY NEXT WEEK...WITH
MONDAY NIGHT/TUESDAY LOOKING LIKE THE NEXT SOMEWHAT ACTIVE
WEATHER DAY AFTER FRIDAY NIGHT/SATURDAY. THERE IS CONSIDERABLY
GOOD AGREEMENT BETWEEN THE GFS AND EC IN THE LONG TERM...AND THE
CURRENT MODELS SUGGEST HIGH PRESSURE MAY ARRIVE BY THE END OF NEXT
WEEK.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1058 PM MDT WED AUG 20 2014

PRECIP HAS JUST ABOUT ENDED ACROSS THE CWA WITH VFR CONDITIONS
BECOMING PREDOMINANT. MORE STORMS AND SHOWERS EXPECTED AGAIN
TOMORROW BUT STILL THINKING COVERAGE WILL BE LESS WITH ONLY
KASE...KEGE AND KTEX MAYBE SEEING SOME PRECIP. VCSH FOR KASE AND
KEGE WITH VCTS FOR KTEX IN THE AFTERNOON LOOKS A SAFE BET FOR NOW
WITH LOW TO MEDIUM CONFIDENCE. REMAINING TAF SITES SHOULD REMAIN
VFR WITH SOME HIGH CIGS MOVING IN DURING THE AFTERNOON.

&&

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

$$

UPDATE...TGR
SHORT TERM...CC
LONG TERM...JAM
AVIATION...TGR





000
FXUS65 KGJT 210254
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
854 PM MDT WED AUG 20 2014

.UPDATE...
ISSUED AT 846 PM MDT WED AUG 20 2014

SOME SHOWERS AND STORMS CONTINUING THIS EVENING AS A WEAK WAVE
MOVES OVERHEAD ESPECIALLY FOR NORTHERN AREAS. PLENTY OF CONVECTION
ALSO CONTINUES SOUTH OF SALT LAKE CITY AND IS MOVING TO THE
EAST-NORTHEAST. IF THE CONVECTION HOLDS TOGETHER...WE CAN EXPECT
TO SEE A BIT MORE PRECIPITATION FOR THE NEXT COUPLE OF HOURS SO
BUMPED UP POPS TO ACCOUNT FOR THIS POSSIBILITY NORTH OF I-70. THE
REST OF THE CWA MAY SEE A PASSING SHOWER BUT NOT EXPECTING MUCH
QPF.

&&

.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 308 PM MDT WED AUG 20 2014

DRIER AIR IS ENTRAINING INTO THE AREA FROM THE SOUTHWEST AND THIS
APPEARS TO BE HELPING HOLD DOWN VERTICAL DEVELOPMENT OVER CENTRAL
AND SW CO AND SE UT. A WEAK UPPER TROUGH IS DRAGGING ACROSS NW CO
AND THIS WILL CONTINUE TO PROVIDE THE EXTRA LIFT NEEDED FOR SINGLE
CELL THUNDERSTORMS TO FORM...MAINLY OVER HIGHER TERRAIN. STILL...
WITH A FEW MORE HOURS OF SUN AVAILABLE THE REST OF THE
AFTERNOON...SCATTERED SHOWERS AND TSTMS SHOULD DEVELOP OVER THE
MOUNTAINS OF CENTRAL CO AFTER ABOUT 22Z AND CONTINUE UNTIL
SUNSET...WITH ISOLATED DEVELOPMENT ELSEWHERE.

CONTINUED DRYING IS EXPECTED LATE TONIGHT THROUGH THU NGT WITH
LOWER POPS AND CLOUD COVER EXPECTED. THE INTERESTING THING TO
WATCH WILL BE THE INTERACTION OF MOISTURE FROM TROPICAL STORM
LOWELL IN THE ERN PACIFIC WITH THE APPROACH TROUGH FROM THE NW.
SOME MOISTURE IS BEING DRAWN NORTH OVER BAJA CALIFORNIA AND IS
DRAWING A BEAD ON THE FOUR CORNERS. BY THU NIGHT THE NAM12
COMBINES THIS MOISTURE WITH THE NEXT MONSOONAL SURGE COMING UP
FROM NW MEXICO.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 308 PM MDT WED AUG 20 2014

TS LOWELL IS FORECAST TO REMAIN NEARLY STATIONARY OFF OF THE
COAST OF BAJA CALIFORNIA AND CONTINUE TO FEED SOME MID TO HIGH
LEVEL MOISTURE INTO THE FOUR CORNERS REGION. ANOTHER CLOSED LOW
IS FORECAST TO DROP INTO THE PACIFIC NORTHWEST AS AN OFFSHOOT OF
THE HIGH AMPLITUDE WESTERN US TROUGH IN PLACE. AS THIS CLOSED LOW
DIVES INTO THE INTERMOUNTAIN WEST THIS WEEKEND...TS LOWELL WILL
SLOWLY SHIFT TO THE WEST AND HAVE LESS OF AN INFLUENCE ON MOISTURE
IN THE REGION. FRIDAY NIGHT...THE APPROACHING LONGWAVE TROUGH WILL
BRING THE COUPLING OF A BAROCLINIC ZONE AND UPPER LEVEL JET WHICH
SHOULD BRING NOCTURNAL ACTIVITY TO THE NORTHERN PART OF THE GJT
CWA. QG FORCING IS MODERATE WITH THIS BOUNDARY. EXPECTING RAIN
AND STORMS FRIDAY NIGHT THROUGH SATURDAY MORNING ACROSS NORTHERN
UTAH AND COLORADO...WITH SCATTERED PRECIPITATION OVER THE
MOUNTAINS ELSEWHERE.

THIS TROUGHY PATTERN WILL CONTINUE THROUGH EARLY NEXT WEEK...WITH
MONDAY NIGHT/TUESDAY LOOKING LIKE THE NEXT SOMEWHAT ACTIVE
WEATHER DAY AFTER FRIDAY NIGHT/SATURDAY. THERE IS CONSIDERABLY
GOOD AGREEMENT BETWEEN THE GFS AND EC IN THE LONG TERM...AND THE
CURRENT MODELS SUGGEST HIGH PRESSURE MAY ARRIVE BY THE END OF NEXT
WEEK.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 528 PM MDT WED AUG 20 2014

SOME ISOLATED CONVECTION HAS FIRED THIS AFTERNOON AFFECTING KVEL
AND KCNY WITH VCTS AND -TSRA ON STATION WITH REPORTS OF SOME GUSTY
WINDS OF 35 TO 40 MPH. A WEAK WAVE IS MOVING OVERHEAD WHICH MAY
CAUSE MORE CONVECTION TO FIRE THROUGH 06Z THOUGH TAF SITES WILL
LIKELY REMAIN UNAFFECTED. SOME ISOLD CONVECTION POSSIBLE THURSDAY
BUT COVERAGE LOOKS TO BE ON THE LOW SIDE WITH AERODROMES LIKELY
REMAINING VFR THROUGH THE DAY.


&&

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

$$

UPDATE...TGR
SHORT TERM...CC
LONG TERM...JAM
AVIATION...TGR





000
FXUS65 KGJT 210254
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
854 PM MDT WED AUG 20 2014

.UPDATE...
ISSUED AT 846 PM MDT WED AUG 20 2014

SOME SHOWERS AND STORMS CONTINUING THIS EVENING AS A WEAK WAVE
MOVES OVERHEAD ESPECIALLY FOR NORTHERN AREAS. PLENTY OF CONVECTION
ALSO CONTINUES SOUTH OF SALT LAKE CITY AND IS MOVING TO THE
EAST-NORTHEAST. IF THE CONVECTION HOLDS TOGETHER...WE CAN EXPECT
TO SEE A BIT MORE PRECIPITATION FOR THE NEXT COUPLE OF HOURS SO
BUMPED UP POPS TO ACCOUNT FOR THIS POSSIBILITY NORTH OF I-70. THE
REST OF THE CWA MAY SEE A PASSING SHOWER BUT NOT EXPECTING MUCH
QPF.

&&

.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 308 PM MDT WED AUG 20 2014

DRIER AIR IS ENTRAINING INTO THE AREA FROM THE SOUTHWEST AND THIS
APPEARS TO BE HELPING HOLD DOWN VERTICAL DEVELOPMENT OVER CENTRAL
AND SW CO AND SE UT. A WEAK UPPER TROUGH IS DRAGGING ACROSS NW CO
AND THIS WILL CONTINUE TO PROVIDE THE EXTRA LIFT NEEDED FOR SINGLE
CELL THUNDERSTORMS TO FORM...MAINLY OVER HIGHER TERRAIN. STILL...
WITH A FEW MORE HOURS OF SUN AVAILABLE THE REST OF THE
AFTERNOON...SCATTERED SHOWERS AND TSTMS SHOULD DEVELOP OVER THE
MOUNTAINS OF CENTRAL CO AFTER ABOUT 22Z AND CONTINUE UNTIL
SUNSET...WITH ISOLATED DEVELOPMENT ELSEWHERE.

CONTINUED DRYING IS EXPECTED LATE TONIGHT THROUGH THU NGT WITH
LOWER POPS AND CLOUD COVER EXPECTED. THE INTERESTING THING TO
WATCH WILL BE THE INTERACTION OF MOISTURE FROM TROPICAL STORM
LOWELL IN THE ERN PACIFIC WITH THE APPROACH TROUGH FROM THE NW.
SOME MOISTURE IS BEING DRAWN NORTH OVER BAJA CALIFORNIA AND IS
DRAWING A BEAD ON THE FOUR CORNERS. BY THU NIGHT THE NAM12
COMBINES THIS MOISTURE WITH THE NEXT MONSOONAL SURGE COMING UP
FROM NW MEXICO.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 308 PM MDT WED AUG 20 2014

TS LOWELL IS FORECAST TO REMAIN NEARLY STATIONARY OFF OF THE
COAST OF BAJA CALIFORNIA AND CONTINUE TO FEED SOME MID TO HIGH
LEVEL MOISTURE INTO THE FOUR CORNERS REGION. ANOTHER CLOSED LOW
IS FORECAST TO DROP INTO THE PACIFIC NORTHWEST AS AN OFFSHOOT OF
THE HIGH AMPLITUDE WESTERN US TROUGH IN PLACE. AS THIS CLOSED LOW
DIVES INTO THE INTERMOUNTAIN WEST THIS WEEKEND...TS LOWELL WILL
SLOWLY SHIFT TO THE WEST AND HAVE LESS OF AN INFLUENCE ON MOISTURE
IN THE REGION. FRIDAY NIGHT...THE APPROACHING LONGWAVE TROUGH WILL
BRING THE COUPLING OF A BAROCLINIC ZONE AND UPPER LEVEL JET WHICH
SHOULD BRING NOCTURNAL ACTIVITY TO THE NORTHERN PART OF THE GJT
CWA. QG FORCING IS MODERATE WITH THIS BOUNDARY. EXPECTING RAIN
AND STORMS FRIDAY NIGHT THROUGH SATURDAY MORNING ACROSS NORTHERN
UTAH AND COLORADO...WITH SCATTERED PRECIPITATION OVER THE
MOUNTAINS ELSEWHERE.

THIS TROUGHY PATTERN WILL CONTINUE THROUGH EARLY NEXT WEEK...WITH
MONDAY NIGHT/TUESDAY LOOKING LIKE THE NEXT SOMEWHAT ACTIVE
WEATHER DAY AFTER FRIDAY NIGHT/SATURDAY. THERE IS CONSIDERABLY
GOOD AGREEMENT BETWEEN THE GFS AND EC IN THE LONG TERM...AND THE
CURRENT MODELS SUGGEST HIGH PRESSURE MAY ARRIVE BY THE END OF NEXT
WEEK.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 528 PM MDT WED AUG 20 2014

SOME ISOLATED CONVECTION HAS FIRED THIS AFTERNOON AFFECTING KVEL
AND KCNY WITH VCTS AND -TSRA ON STATION WITH REPORTS OF SOME GUSTY
WINDS OF 35 TO 40 MPH. A WEAK WAVE IS MOVING OVERHEAD WHICH MAY
CAUSE MORE CONVECTION TO FIRE THROUGH 06Z THOUGH TAF SITES WILL
LIKELY REMAIN UNAFFECTED. SOME ISOLD CONVECTION POSSIBLE THURSDAY
BUT COVERAGE LOOKS TO BE ON THE LOW SIDE WITH AERODROMES LIKELY
REMAINING VFR THROUGH THE DAY.


&&

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

$$

UPDATE...TGR
SHORT TERM...CC
LONG TERM...JAM
AVIATION...TGR




000
FXUS65 KGJT 202336
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
536 PM MDT WED AUG 20 2014

.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 308 PM MDT WED AUG 20 2014

DRIER AIR IS ENTRAINING INTO THE AREA FROM THE SOUTHWEST AND THIS
APPEARS TO BE HELPING HOLD DOWN VERTICAL DEVELOPMENT OVER CENTRAL
AND SW CO AND SE UT. A WEAK UPPER TROUGH IS DRAGGING ACROSS NW CO
AND THIS WILL CONTINUE TO PROVIDE THE EXTRA LIFT NEEDED FOR SINGLE
CELL THUNDERSTORMS TO FORM...MAINLY OVER HIGHER TERRAIN. STILL...
WITH A FEW MORE HOURS OF SUN AVAILABLE THE REST OF THE
AFTERNOON...SCATTERED SHOWERS AND TSTMS SHOULD DEVELOP OVER THE
MOUNTAINS OF CENTRAL CO AFTER ABOUT 22Z AND CONTINUE UNTIL
SUNSET...WITH ISOLATED DEVELOPMENT ELSEWHERE.

CONTINUED DRYING IS EXPECTED LATE TONIGHT THROUGH THU NGT WITH
LOWER POPS AND CLOUD COVER EXPECTED. THE INTERESTING THING TO
WATCH WILL BE THE INTERACTION OF MOISTURE FROM TROPICAL STORM
LOWELL IN THE ERN PACIFIC WITH THE APPROACH TROUGH FROM THE NW.
SOME MOISTURE IS BEING DRAWN NORTH OVER BAJA CALIFORNIA AND IS
DRAWING A BEAD ON THE FOUR CORNERS. BY THU NIGHT THE NAM12
COMBINES THIS MOISTURE WITH THE NEXT MONSOONAL SURGE COMING UP
FROM NW MEXICO.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 308 PM MDT WED AUG 20 2014

TS LOWELL IS FORECAST TO REMAIN NEARLY STATIONARY OFF OF THE
COAST OF BAJA CALIFORNIA AND CONTINUE TO FEED SOME MID TO HIGH
LEVEL MOISTURE INTO THE FOUR CORNERS REGION. ANOTHER CLOSED LOW
IS FORECAST TO DROP INTO THE PACIFIC NORTHWEST AS AN OFFSHOOT OF
THE HIGH AMPLITUDE WESTERN US TROUGH IN PLACE. AS THIS CLOSED LOW
DIVES INTO THE INTERMOUNTAIN WEST THIS WEEKEND...TS LOWELL WILL
SLOWLY SHIFT TO THE WEST AND HAVE LESS OF AN INFLUENCE ON MOISTURE
IN THE REGION. FRIDAY NIGHT...THE APPROACHING LONGWAVE TROUGH WILL
BRING THE COUPLING OF A BAROCLINIC ZONE AND UPPER LEVEL JET WHICH
SHOULD BRING NOCTURNAL ACTIVITY TO THE NORTHERN PART OF THE GJT
CWA. QG FORCING IS MODERATE WITH THIS BOUNDARY. EXPECTING RAIN
AND STORMS FRIDAY NIGHT THROUGH SATURDAY MORNING ACROSS NORTHERN
UTAH AND COLORADO...WITH SCATTERED PRECIPITATION OVER THE
MOUNTAINS ELSEWHERE.

THIS TROUGHY PATTERN WILL CONTINUE THROUGH EARLY NEXT WEEK...WITH
MONDAY NIGHT/TUESDAY LOOKING LIKE THE NEXT SOMEWHAT ACTIVE
WEATHER DAY AFTER FRIDAY NIGHT/SATURDAY. THERE IS CONSIDERABLY
GOOD AGREEMENT BETWEEN THE GFS AND EC IN THE LONG TERM...AND THE
CURRENT MODELS SUGGEST HIGH PRESSURE MAY ARRIVE BY THE END OF NEXT
WEEK.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 528 PM MDT WED AUG 20 2014

SOME ISOLATED CONVECTION HAS FIRED THIS AFTERNOON AFFECTING KVEL
AND KCNY WITH VCTS AND -TSRA ON STATION WITH REPORTS OF SOME GUSTY
WINDS OF 35 TO 40 MPH. A WEAK WAVE IS MOVING OVERHEAD WHICH MAY
CAUSE MORE CONVECTION TO FIRE THROUGH 06Z THOUGH TAF SITES WILL
LIKELY REMAIN UNAFFECTED. SOME ISOLD CONVECTION POSSIBLE THURSDAY
BUT COVERAGE LOOKS TO BE ON THE LOW SIDE WITH AERODROMES LIKELY
REMAINING VFR THROUGH THE DAY.

&&

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

$$

SHORT TERM...CC
LONG TERM...JAM
AVIATION...TGR





000
FXUS65 KGJT 202336
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
536 PM MDT WED AUG 20 2014

.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 308 PM MDT WED AUG 20 2014

DRIER AIR IS ENTRAINING INTO THE AREA FROM THE SOUTHWEST AND THIS
APPEARS TO BE HELPING HOLD DOWN VERTICAL DEVELOPMENT OVER CENTRAL
AND SW CO AND SE UT. A WEAK UPPER TROUGH IS DRAGGING ACROSS NW CO
AND THIS WILL CONTINUE TO PROVIDE THE EXTRA LIFT NEEDED FOR SINGLE
CELL THUNDERSTORMS TO FORM...MAINLY OVER HIGHER TERRAIN. STILL...
WITH A FEW MORE HOURS OF SUN AVAILABLE THE REST OF THE
AFTERNOON...SCATTERED SHOWERS AND TSTMS SHOULD DEVELOP OVER THE
MOUNTAINS OF CENTRAL CO AFTER ABOUT 22Z AND CONTINUE UNTIL
SUNSET...WITH ISOLATED DEVELOPMENT ELSEWHERE.

CONTINUED DRYING IS EXPECTED LATE TONIGHT THROUGH THU NGT WITH
LOWER POPS AND CLOUD COVER EXPECTED. THE INTERESTING THING TO
WATCH WILL BE THE INTERACTION OF MOISTURE FROM TROPICAL STORM
LOWELL IN THE ERN PACIFIC WITH THE APPROACH TROUGH FROM THE NW.
SOME MOISTURE IS BEING DRAWN NORTH OVER BAJA CALIFORNIA AND IS
DRAWING A BEAD ON THE FOUR CORNERS. BY THU NIGHT THE NAM12
COMBINES THIS MOISTURE WITH THE NEXT MONSOONAL SURGE COMING UP
FROM NW MEXICO.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 308 PM MDT WED AUG 20 2014

TS LOWELL IS FORECAST TO REMAIN NEARLY STATIONARY OFF OF THE
COAST OF BAJA CALIFORNIA AND CONTINUE TO FEED SOME MID TO HIGH
LEVEL MOISTURE INTO THE FOUR CORNERS REGION. ANOTHER CLOSED LOW
IS FORECAST TO DROP INTO THE PACIFIC NORTHWEST AS AN OFFSHOOT OF
THE HIGH AMPLITUDE WESTERN US TROUGH IN PLACE. AS THIS CLOSED LOW
DIVES INTO THE INTERMOUNTAIN WEST THIS WEEKEND...TS LOWELL WILL
SLOWLY SHIFT TO THE WEST AND HAVE LESS OF AN INFLUENCE ON MOISTURE
IN THE REGION. FRIDAY NIGHT...THE APPROACHING LONGWAVE TROUGH WILL
BRING THE COUPLING OF A BAROCLINIC ZONE AND UPPER LEVEL JET WHICH
SHOULD BRING NOCTURNAL ACTIVITY TO THE NORTHERN PART OF THE GJT
CWA. QG FORCING IS MODERATE WITH THIS BOUNDARY. EXPECTING RAIN
AND STORMS FRIDAY NIGHT THROUGH SATURDAY MORNING ACROSS NORTHERN
UTAH AND COLORADO...WITH SCATTERED PRECIPITATION OVER THE
MOUNTAINS ELSEWHERE.

THIS TROUGHY PATTERN WILL CONTINUE THROUGH EARLY NEXT WEEK...WITH
MONDAY NIGHT/TUESDAY LOOKING LIKE THE NEXT SOMEWHAT ACTIVE
WEATHER DAY AFTER FRIDAY NIGHT/SATURDAY. THERE IS CONSIDERABLY
GOOD AGREEMENT BETWEEN THE GFS AND EC IN THE LONG TERM...AND THE
CURRENT MODELS SUGGEST HIGH PRESSURE MAY ARRIVE BY THE END OF NEXT
WEEK.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 528 PM MDT WED AUG 20 2014

SOME ISOLATED CONVECTION HAS FIRED THIS AFTERNOON AFFECTING KVEL
AND KCNY WITH VCTS AND -TSRA ON STATION WITH REPORTS OF SOME GUSTY
WINDS OF 35 TO 40 MPH. A WEAK WAVE IS MOVING OVERHEAD WHICH MAY
CAUSE MORE CONVECTION TO FIRE THROUGH 06Z THOUGH TAF SITES WILL
LIKELY REMAIN UNAFFECTED. SOME ISOLD CONVECTION POSSIBLE THURSDAY
BUT COVERAGE LOOKS TO BE ON THE LOW SIDE WITH AERODROMES LIKELY
REMAINING VFR THROUGH THE DAY.

&&

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

$$

SHORT TERM...CC
LONG TERM...JAM
AVIATION...TGR




000
FXUS65 KGJT 202113
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
313 PM MDT WED AUG 20 2014

.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 308 PM MDT WED AUG 20 2014

DRIER AIR IS ENTRAINING INTO THE AREA FROM THE SOUTHWEST AND THIS
APPEARS TO BE HELPING HOLD DOWN VERTICAL DEVELOPMENT OVER CENTRAL
AND SW CO AND SE UT. A WEAK UPPER TROUGH IS DRAGGING ACROSS NW CO
AND THIS WILL CONTINUE TO PROVIDE THE EXTRA LIFT NEEDED FOR SINGLE
CELL THUNDERSTORMS TO FORM...MAINLY OVER HIGHER TERRAIN. STILL...
WITH A FEW MORE HOURS OF SUN AVAILABLE THE REST OF THE
AFTERNOON...SCATTERED SHOWERS AND TSTMS SHOULD DEVELOP OVER THE
MOUNTAINS OF CENTRAL CO AFTER ABOUT 22Z AND CONTINUE UNTIL
SUNSET...WITH ISOLATED DEVELOPMENT ELSEWHERE.

CONTINUED DRYING IS EXPECTED LATE TONIGHT THROUGH THU NGT WITH
LOWER POPS AND CLOUD COVER EXPECTED. THE INTERESTING THING TO
WATCH WILL BE THE INTERACTION OF MOISTURE FROM TROPICAL STORM
LOWELL IN THE ERN PACIFIC WITH THE APPROACH TROUGH FROM THE NW.
SOME MOISTURE IS BEING DRAWN NORTH OVER BAJA CALIFORNIA AND IS
DRAWING A BEAD ON THE FOUR CORNERS. BY THU NIGHT THE NAM12
COMBINES THIS MOISTURE WITH THE NEXT MONSOONAL SURGE COMING UP
FROM NW MEXICO.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 308 PM MDT WED AUG 20 2014

TS LOWELL IS FORECAST TO REMAIN NEARLY STATIONARY OFF OF THE
COAST OF BAJA CALIFORNIA AND CONTINUE TO FEED SOME MID TO HIGH
LEVEL MOISTURE INTO THE FOUR CORNERS REGION. ANOTHER CLOSED LOW
IS FORECAST TO DROP INTO THE PACIFIC NORTHWEST AS AN OFFSHOOT OF
THE HIGH AMPLITUDE WESTERN US TROUGH IN PLACE. AS THIS CLOSED LOW
DIVES INTO THE INTERMOUNTAIN WEST THIS WEEKEND...TS LOWELL WILL
SLOWLY SHIFT TO THE WEST AND HAVE LESS OF AN INFLUENCE ON MOISTURE
IN THE REGION. FRIDAY NIGHT...THE APPROACHING LONGWAVE TROUGH WILL
BRING THE COUPLING OF A BAROCLINIC ZONE AND UPPER LEVEL JET WHICH
SHOULD BRING NOCTURNAL ACTIVITY TO THE NORTHERN PART OF THE GJT
CWA. QG FORCING IS MODERATE WITH THIS BOUNDARY. EXPECTING RAIN
AND STORMS FRIDAY NIGHT THROUGH SATURDAY MORNING ACROSS NORTHERN
UTAH AND COLORADO...WITH SCATTERED PRECIPITATION OVER THE
MOUNTAINS ELSEWHERE.

THIS TROUGHY PATTERN WILL CONTINUE THROUGH EARLY NEXT WEEK...WITH
MONDAY NIGHT/TUESDAY LOOKING LIKE THE NEXT SOMEWHAT ACTIVE
WEATHER DAY AFTER FRIDAY NIGHT/SATURDAY. THERE IS CONSIDERABLY
GOOD AGREEMENT BETWEEN THE GFS AND EC IN THE LONG TERM...AND THE
CURRENT MODELS SUGGEST HIGH PRESSURE MAY ARRIVE BY THE END OF NEXT
WEEK.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1031 AM MDT WED AUG 20 2014

A DISTURBANCE ALOFT WILL CONTINUE SWEEPING ACROSS NW CO AND NE UT
AND GENERATE SCATTERED SHOWERS AND THUNDERSTORMS THROUGH EARLY THIS
AFTERNOON...GENERALLY NORTH OF THE I-70 CORRIDOR. HIGH MOISTURE
CONTENT AND GENERALLY THICK LOW AND MID LEVEL CLOUD COVER WILL
SUPPRESS STORM DEVELOPMENT OVER MUCH OF THE AREA UNTIL ABOUT
20Z. THEN CLEARING SKIES WILL SPREAD FROM THE SW TO NE...ALLOWING
STORM COVERAGE AND INTENSITY TO INCREASE. MOUNTAINS WILL BE
OBSCURED AT TIMES. TAF SITES ALONG THE I-70 CORRIDOR FACE A GOOD
CHANCE FOR THUNDERSTORM ACTIVITY WITH BRIEF MVFR/IFR VSBY POSSIBLE
IN HEAVY RAIN. THERE IS ONLY A SLIGHT CHANCE THAT THE REMAINDER OF
THE TAF SITES WILL BE DIRECTLY IMPACTED BY THUNDERSTORMS...THOUGH
THERE IS A GOOD CHANCE THAT THUNDERSTORMS WILL BE IN THE VICINITY
THROUGHOUT THE AFTERNOON AND INTO THE EVENING. SHOWERS AND
THUNDERSTORMS WILL LARGELY DIMINISH THIS EVENING WITH VFR
CONDITIONS RETURNING REGION WIDE.

&&

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

$$

SHORT TERM...CC
LONG TERM...JAM
AVIATION...CC




000
FXUS65 KGJT 202113
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
313 PM MDT WED AUG 20 2014

.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 308 PM MDT WED AUG 20 2014

DRIER AIR IS ENTRAINING INTO THE AREA FROM THE SOUTHWEST AND THIS
APPEARS TO BE HELPING HOLD DOWN VERTICAL DEVELOPMENT OVER CENTRAL
AND SW CO AND SE UT. A WEAK UPPER TROUGH IS DRAGGING ACROSS NW CO
AND THIS WILL CONTINUE TO PROVIDE THE EXTRA LIFT NEEDED FOR SINGLE
CELL THUNDERSTORMS TO FORM...MAINLY OVER HIGHER TERRAIN. STILL...
WITH A FEW MORE HOURS OF SUN AVAILABLE THE REST OF THE
AFTERNOON...SCATTERED SHOWERS AND TSTMS SHOULD DEVELOP OVER THE
MOUNTAINS OF CENTRAL CO AFTER ABOUT 22Z AND CONTINUE UNTIL
SUNSET...WITH ISOLATED DEVELOPMENT ELSEWHERE.

CONTINUED DRYING IS EXPECTED LATE TONIGHT THROUGH THU NGT WITH
LOWER POPS AND CLOUD COVER EXPECTED. THE INTERESTING THING TO
WATCH WILL BE THE INTERACTION OF MOISTURE FROM TROPICAL STORM
LOWELL IN THE ERN PACIFIC WITH THE APPROACH TROUGH FROM THE NW.
SOME MOISTURE IS BEING DRAWN NORTH OVER BAJA CALIFORNIA AND IS
DRAWING A BEAD ON THE FOUR CORNERS. BY THU NIGHT THE NAM12
COMBINES THIS MOISTURE WITH THE NEXT MONSOONAL SURGE COMING UP
FROM NW MEXICO.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 308 PM MDT WED AUG 20 2014

TS LOWELL IS FORECAST TO REMAIN NEARLY STATIONARY OFF OF THE
COAST OF BAJA CALIFORNIA AND CONTINUE TO FEED SOME MID TO HIGH
LEVEL MOISTURE INTO THE FOUR CORNERS REGION. ANOTHER CLOSED LOW
IS FORECAST TO DROP INTO THE PACIFIC NORTHWEST AS AN OFFSHOOT OF
THE HIGH AMPLITUDE WESTERN US TROUGH IN PLACE. AS THIS CLOSED LOW
DIVES INTO THE INTERMOUNTAIN WEST THIS WEEKEND...TS LOWELL WILL
SLOWLY SHIFT TO THE WEST AND HAVE LESS OF AN INFLUENCE ON MOISTURE
IN THE REGION. FRIDAY NIGHT...THE APPROACHING LONGWAVE TROUGH WILL
BRING THE COUPLING OF A BAROCLINIC ZONE AND UPPER LEVEL JET WHICH
SHOULD BRING NOCTURNAL ACTIVITY TO THE NORTHERN PART OF THE GJT
CWA. QG FORCING IS MODERATE WITH THIS BOUNDARY. EXPECTING RAIN
AND STORMS FRIDAY NIGHT THROUGH SATURDAY MORNING ACROSS NORTHERN
UTAH AND COLORADO...WITH SCATTERED PRECIPITATION OVER THE
MOUNTAINS ELSEWHERE.

THIS TROUGHY PATTERN WILL CONTINUE THROUGH EARLY NEXT WEEK...WITH
MONDAY NIGHT/TUESDAY LOOKING LIKE THE NEXT SOMEWHAT ACTIVE
WEATHER DAY AFTER FRIDAY NIGHT/SATURDAY. THERE IS CONSIDERABLY
GOOD AGREEMENT BETWEEN THE GFS AND EC IN THE LONG TERM...AND THE
CURRENT MODELS SUGGEST HIGH PRESSURE MAY ARRIVE BY THE END OF NEXT
WEEK.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1031 AM MDT WED AUG 20 2014

A DISTURBANCE ALOFT WILL CONTINUE SWEEPING ACROSS NW CO AND NE UT
AND GENERATE SCATTERED SHOWERS AND THUNDERSTORMS THROUGH EARLY THIS
AFTERNOON...GENERALLY NORTH OF THE I-70 CORRIDOR. HIGH MOISTURE
CONTENT AND GENERALLY THICK LOW AND MID LEVEL CLOUD COVER WILL
SUPPRESS STORM DEVELOPMENT OVER MUCH OF THE AREA UNTIL ABOUT
20Z. THEN CLEARING SKIES WILL SPREAD FROM THE SW TO NE...ALLOWING
STORM COVERAGE AND INTENSITY TO INCREASE. MOUNTAINS WILL BE
OBSCURED AT TIMES. TAF SITES ALONG THE I-70 CORRIDOR FACE A GOOD
CHANCE FOR THUNDERSTORM ACTIVITY WITH BRIEF MVFR/IFR VSBY POSSIBLE
IN HEAVY RAIN. THERE IS ONLY A SLIGHT CHANCE THAT THE REMAINDER OF
THE TAF SITES WILL BE DIRECTLY IMPACTED BY THUNDERSTORMS...THOUGH
THERE IS A GOOD CHANCE THAT THUNDERSTORMS WILL BE IN THE VICINITY
THROUGHOUT THE AFTERNOON AND INTO THE EVENING. SHOWERS AND
THUNDERSTORMS WILL LARGELY DIMINISH THIS EVENING WITH VFR
CONDITIONS RETURNING REGION WIDE.

&&

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

$$

SHORT TERM...CC
LONG TERM...JAM
AVIATION...CC





000
FXUS65 KGJT 201641
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1041 AM MDT WED AUG 20 2014

.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 357 AM MDT WED AUG 20 2014

LIGHT SHOWERS CONTINUED OVER PORTIONS OF CENTRAL AND NORTHWEST
COLORADO AND NORTHEAST UTAH EARLY THIS MORNING. LIFT ASSOCIATED
WITH THE LEFT EXIT REGION OF A JET STREAK ON THE EASTERN SIDE OF
A CLOSED LOW CIRCULATION OFF THE SOUTHERN CALIFORNIA COAST
APPEARED TO BE RESPONSIBLE FOR SUSTAINING MOIST CONVECTION.

THE INFLUENCE OF JET LEVEL DIVERGENCE DIMINISHES LATE TONIGHT INTO
WEDNESDAY MORNING. THEREAFTER...A SHORTWAVE WHICH WAS OVER WEST-
CENTRAL UTAH EARLY THIS MORNING WILL BECOME ENTRAINED IN THE
NORTHERLY STREAM...MOVING ACROSS NORTHEAST UTAH INTO NORTHWEST
COLORADO THIS MORNING. CONSEQUENTLY...SHOWERS AND EMBEDDED
THUNDERSTORMS WILL BE FAVORED ACROSS THE NORTH BEFORE NOON. A
MORE SHEARED SECONDARY WAVE WILL MOVE ALONG THE NORTHERN BORDER
AREA DURING THE AFTERNOON CONTINUING TO FOCUS SHOWERS AND
THUNDERSTORMS ACROSS THAT PORTION OF THE FORECAST AREA.

ELSEWHERE...DAYTIME WARMING WILL SPARK SCATTERED SHOWERS AND
THUNDERSTORMS...MAINLY OVER THE HIGHER TERRAIN. CLOUD COVER WILL
REMAIN PRETTY EXPANSIVE LIMITING INSOLATION AND IN TURN...STORM
STRENGTH. PRECIPITABLE WATER VALUES WILL BE FALLING BELOW AN INCH
AS DRIER MID-LEVEL FLOW MOVES IN. THIS...COMBINED WITH STEERING
WINDS STILL AVERAGING NEAR 20 KTS WILL LIMIT THE THREAT OF
EXCESSIVE RAINFALL AND FLOODING. HOWEVER...LOCALIZED FLOODING
CANNOT BE COMPLETELY RULED OUT. CLOUD COVER AND SHOWERS WILL
CONTINUE TO BRING COOLER THAN NORMAL AFTERNOON HIGHS AND MOS
GUIDANCE SEEMED TO CAPTURE THIS WELL.

THE UPPER LOW OVER SOUTHERN CALIFORNIA WILL BEGIN TO WEAKEN AND
SHIFT INLAND LATE TONIGHT THROUGH THU. THIS KEEPS THE AREA UNDER
A SOUTH-SOUTHWEST FLOW. WHILE THIS FLOW REGIME IS FAVORABLE FOR
KEEPING THE SUB-TROPICAL TAP OPEN...IT DOES LOOK LIKE THERE WILL
BE A MODEST DOWNTURN IN MOISTURE THROUGH THURSDAY. PWAT VALUES
WILL BE MOSTLY BETWEEN HALF AND THREE QUARTERS INCH. AFTER THE
DIURNAL ACTIVITY DIMINISHES THIS EVENING...EXPECT A FEW NOCTURNAL
SHOWERS AND THUNDERSTORMS OVERNIGHT TONIGHT. THEN WITH DAYTIME
HEATING ON THU...MOSTLY SCATTERED SHOWERS AND THUNDERSTORMS WILL
DEVELOP IN THE AFTERNOON FOR THE MOUNTAINS...WITH LESS COVERAGE
IN THE VALLEYS.

.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 357 AM MDT WED AUG 20 2014

THERE ARE STILL SOME DIFFERENCES IN THE TIMING OF WHEN THE
WEAKENED SOUTHERN CALIFORNIA LOW WILL PASS OVER THE AREA. THE
FASTER GFS SHOWS IT OVER THE FOUR CORNERS AT 12Z/6AM MDT
FRI...WITH THE NAM/EC ABOUT 9-12 HOURS LATER. MODELS ALSO
INDICATED THAT SOME MOISTURE FROM TROPICAL STORM LOWELL COULD GET
ENTRAINED IN THE SOUTHWEST FLOW AHEAD OF THE LOW. ESPECIALLY IF
THE GFS VERIFIES...THU NIGHT COULD BE RELATIVELY ACTIVE WITH
NIGHTTIME CONVECTION INCREASING AFTER MIDNIGHT. BUT EVEN THE
SLOWER NAM/EC SOLUTIONS WOULD ENHANCE INSTABILITY TOWARDS MORNING.
THEN DAYTIME HEATING WILL ADD TO THE MIX ON FRI...FOR BETTER
AFTERNOON SHOWERS AND THUNDERSTORMS. TEMPERATURES WILL REMAIN
BELOW NORMAL.

THE UNSEASONABLE LONG-WAVE TROUGH REMAINS OVER THE ROCKIES FROM
SATURDAY INTO TUESDAY WITH A SERIES OF SHORTWAVES MOVING THROUGH
DURING THIS TIME FRAME. LITTLE SKILL IN TIMING OF THOSE
DISTURBANCES THIS FAR OUT...SO WILL CONTINUE TO FORECAST MAINLY
DIURNAL SHOWERS AND THUNDERSTORMS...FAVORING THE MOUNTAINS...THIS
WEEKEND THROUGH EARLY NEXT WEEK. MOISTURE DEPTH AND STORM MOTION
NOT FAVORABLE FOR SIGNIFICANT HEAVY RAIN. STAGNANT PATTERN FAVORS
LITTLE CHANGE IN TEMPERATURES WHICH SHOULD REMAIN COOL DURING
THIS PERIOD.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1031 AM MDT WED AUG 20 2014

A DISTURBANCE ALOFT WILL CONTINUE SWEEPING ACROSS NW CO AND NE UT
AND GENERATE SCATTERED SHOWERS AND THUNDERSTORMS THROUGH EARLY THIS
AFTERNOON...GENERALLY NORTH OF THE I-70 CORRIDOR. HIGH MOISTURE
CONTENT AND GENERALLY THICK LOW AND MID LEVEL CLOUD COVER WILL
SUPPRESS STORM DEVELOPMENT OVER MUCH OF THE AREA UNTIL ABOUT
20Z. THEN CLEARING SKIES WILL SPREAD FROM THE SW TO NE...ALLOWING
STORM COVERAGE AND INTENSITY TO INCREASE. MOUNTAINS WILL BE
OBSCURED AT TIMES. TAF SITES ALONG THE I-70 CORRIDOR FACE A GOOD
CHANCE FOR THUNDERSTORM ACTIVITY WITH BRIEF MVFR/IFR VSBY POSSIBLE
IN HEAVY RAIN. THERE IS ONLY A SLIGHT CHANCE THAT THE REMAINDER OF
THE TAF SITES WILL BE DIRECTLY IMPACTED BY THUNDERSTORMS...THOUGH
THERE IS A GOOD CHANCE THAT THUNDERSTORMS WILL BE IN THE VICINITY
THROUGHOUT THE AFTERNOON AND INTO THE EVENING. SHOWERS AND
THUNDERSTORMS WILL LARGELY DIMINISH THIS EVENING WITH VFR
CONDITIONS RETURNING REGION WIDE.

&&

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

$$

SHORT TERM...NL/EH
LONG TERM...EH/NL
AVIATION...CC




000
FXUS65 KGJT 201641
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1041 AM MDT WED AUG 20 2014

.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 357 AM MDT WED AUG 20 2014

LIGHT SHOWERS CONTINUED OVER PORTIONS OF CENTRAL AND NORTHWEST
COLORADO AND NORTHEAST UTAH EARLY THIS MORNING. LIFT ASSOCIATED
WITH THE LEFT EXIT REGION OF A JET STREAK ON THE EASTERN SIDE OF
A CLOSED LOW CIRCULATION OFF THE SOUTHERN CALIFORNIA COAST
APPEARED TO BE RESPONSIBLE FOR SUSTAINING MOIST CONVECTION.

THE INFLUENCE OF JET LEVEL DIVERGENCE DIMINISHES LATE TONIGHT INTO
WEDNESDAY MORNING. THEREAFTER...A SHORTWAVE WHICH WAS OVER WEST-
CENTRAL UTAH EARLY THIS MORNING WILL BECOME ENTRAINED IN THE
NORTHERLY STREAM...MOVING ACROSS NORTHEAST UTAH INTO NORTHWEST
COLORADO THIS MORNING. CONSEQUENTLY...SHOWERS AND EMBEDDED
THUNDERSTORMS WILL BE FAVORED ACROSS THE NORTH BEFORE NOON. A
MORE SHEARED SECONDARY WAVE WILL MOVE ALONG THE NORTHERN BORDER
AREA DURING THE AFTERNOON CONTINUING TO FOCUS SHOWERS AND
THUNDERSTORMS ACROSS THAT PORTION OF THE FORECAST AREA.

ELSEWHERE...DAYTIME WARMING WILL SPARK SCATTERED SHOWERS AND
THUNDERSTORMS...MAINLY OVER THE HIGHER TERRAIN. CLOUD COVER WILL
REMAIN PRETTY EXPANSIVE LIMITING INSOLATION AND IN TURN...STORM
STRENGTH. PRECIPITABLE WATER VALUES WILL BE FALLING BELOW AN INCH
AS DRIER MID-LEVEL FLOW MOVES IN. THIS...COMBINED WITH STEERING
WINDS STILL AVERAGING NEAR 20 KTS WILL LIMIT THE THREAT OF
EXCESSIVE RAINFALL AND FLOODING. HOWEVER...LOCALIZED FLOODING
CANNOT BE COMPLETELY RULED OUT. CLOUD COVER AND SHOWERS WILL
CONTINUE TO BRING COOLER THAN NORMAL AFTERNOON HIGHS AND MOS
GUIDANCE SEEMED TO CAPTURE THIS WELL.

THE UPPER LOW OVER SOUTHERN CALIFORNIA WILL BEGIN TO WEAKEN AND
SHIFT INLAND LATE TONIGHT THROUGH THU. THIS KEEPS THE AREA UNDER
A SOUTH-SOUTHWEST FLOW. WHILE THIS FLOW REGIME IS FAVORABLE FOR
KEEPING THE SUB-TROPICAL TAP OPEN...IT DOES LOOK LIKE THERE WILL
BE A MODEST DOWNTURN IN MOISTURE THROUGH THURSDAY. PWAT VALUES
WILL BE MOSTLY BETWEEN HALF AND THREE QUARTERS INCH. AFTER THE
DIURNAL ACTIVITY DIMINISHES THIS EVENING...EXPECT A FEW NOCTURNAL
SHOWERS AND THUNDERSTORMS OVERNIGHT TONIGHT. THEN WITH DAYTIME
HEATING ON THU...MOSTLY SCATTERED SHOWERS AND THUNDERSTORMS WILL
DEVELOP IN THE AFTERNOON FOR THE MOUNTAINS...WITH LESS COVERAGE
IN THE VALLEYS.

.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 357 AM MDT WED AUG 20 2014

THERE ARE STILL SOME DIFFERENCES IN THE TIMING OF WHEN THE
WEAKENED SOUTHERN CALIFORNIA LOW WILL PASS OVER THE AREA. THE
FASTER GFS SHOWS IT OVER THE FOUR CORNERS AT 12Z/6AM MDT
FRI...WITH THE NAM/EC ABOUT 9-12 HOURS LATER. MODELS ALSO
INDICATED THAT SOME MOISTURE FROM TROPICAL STORM LOWELL COULD GET
ENTRAINED IN THE SOUTHWEST FLOW AHEAD OF THE LOW. ESPECIALLY IF
THE GFS VERIFIES...THU NIGHT COULD BE RELATIVELY ACTIVE WITH
NIGHTTIME CONVECTION INCREASING AFTER MIDNIGHT. BUT EVEN THE
SLOWER NAM/EC SOLUTIONS WOULD ENHANCE INSTABILITY TOWARDS MORNING.
THEN DAYTIME HEATING WILL ADD TO THE MIX ON FRI...FOR BETTER
AFTERNOON SHOWERS AND THUNDERSTORMS. TEMPERATURES WILL REMAIN
BELOW NORMAL.

THE UNSEASONABLE LONG-WAVE TROUGH REMAINS OVER THE ROCKIES FROM
SATURDAY INTO TUESDAY WITH A SERIES OF SHORTWAVES MOVING THROUGH
DURING THIS TIME FRAME. LITTLE SKILL IN TIMING OF THOSE
DISTURBANCES THIS FAR OUT...SO WILL CONTINUE TO FORECAST MAINLY
DIURNAL SHOWERS AND THUNDERSTORMS...FAVORING THE MOUNTAINS...THIS
WEEKEND THROUGH EARLY NEXT WEEK. MOISTURE DEPTH AND STORM MOTION
NOT FAVORABLE FOR SIGNIFICANT HEAVY RAIN. STAGNANT PATTERN FAVORS
LITTLE CHANGE IN TEMPERATURES WHICH SHOULD REMAIN COOL DURING
THIS PERIOD.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1031 AM MDT WED AUG 20 2014

A DISTURBANCE ALOFT WILL CONTINUE SWEEPING ACROSS NW CO AND NE UT
AND GENERATE SCATTERED SHOWERS AND THUNDERSTORMS THROUGH EARLY THIS
AFTERNOON...GENERALLY NORTH OF THE I-70 CORRIDOR. HIGH MOISTURE
CONTENT AND GENERALLY THICK LOW AND MID LEVEL CLOUD COVER WILL
SUPPRESS STORM DEVELOPMENT OVER MUCH OF THE AREA UNTIL ABOUT
20Z. THEN CLEARING SKIES WILL SPREAD FROM THE SW TO NE...ALLOWING
STORM COVERAGE AND INTENSITY TO INCREASE. MOUNTAINS WILL BE
OBSCURED AT TIMES. TAF SITES ALONG THE I-70 CORRIDOR FACE A GOOD
CHANCE FOR THUNDERSTORM ACTIVITY WITH BRIEF MVFR/IFR VSBY POSSIBLE
IN HEAVY RAIN. THERE IS ONLY A SLIGHT CHANCE THAT THE REMAINDER OF
THE TAF SITES WILL BE DIRECTLY IMPACTED BY THUNDERSTORMS...THOUGH
THERE IS A GOOD CHANCE THAT THUNDERSTORMS WILL BE IN THE VICINITY
THROUGHOUT THE AFTERNOON AND INTO THE EVENING. SHOWERS AND
THUNDERSTORMS WILL LARGELY DIMINISH THIS EVENING WITH VFR
CONDITIONS RETURNING REGION WIDE.

&&

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

$$

SHORT TERM...NL/EH
LONG TERM...EH/NL
AVIATION...CC





000
FXUS65 KGJT 200957
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
357 AM MDT WED AUG 20 2014

.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 357 AM MDT WED AUG 20 2014

LIGHT SHOWERS CONTINUED OVER PORTIONS OF CENTRAL AND NORTHWEST
COLORADO AND NORTHEAST UTAH EARLY THIS MORNING. LIFT ASSOCIATED
WITH THE LEFT EXIT REGION OF A JET STREAK ON THE EASTERN SIDE OF
A CLOSED LOW CIRCULATION OFF THE SOUTHERN CALIFORNIA COAST
APPEARED TO BE RESPONSIBLE FOR SUSTAINING MOIST CONVECTION.

THE INFLUENCE OF JET LEVEL DIVERGENCE DIMINISHES LATE TONIGHT INTO
WEDNESDAY MORNING. THEREAFTER...A SHORTWAVE WHICH WAS OVER WEST-
CENTRAL UTAH EARLY THIS MORNING WILL BECOME ENTRAINED IN THE
NORTHERLY STREAM...MOVING ACROSS NORTHEAST UTAH INTO NORTHWEST
COLORADO THIS MORNING. CONSEQUENTLY...SHOWERS AND EMBEDDED
THUNDERSTORMS WILL BE FAVORED ACROSS THE NORTH BEFORE NOON. A
MORE SHEARED SECONDARY WAVE WILL MOVE ALONG THE NORTHERN BORDER
AREA DURING THE AFTERNOON CONTINUING TO FOCUS SHOWERS AND
THUNDERSTORMS ACROSS THAT PORTION OF THE FORECAST AREA.

ELSEWHERE...DAYTIME WARMING WILL SPARK SCATTERED SHOWERS AND
THUNDERSTORMS...MAINLY OVER THE HIGHER TERRAIN. CLOUD COVER WILL
REMAIN PRETTY EXPANSIVE LIMITING INSOLATION AND IN TURN...STORM
STRENGTH. PRECIPITABLE WATER VALUES WILL BE FALLING BELOW AN INCH
AS DRIER MID-LEVEL FLOW MOVES IN. THIS...COMBINED WITH STEERING
WINDS STILL AVERAGING NEAR 20 KTS WILL LIMIT THE THREAT OF
EXCESSIVE RAINFALL AND FLOODING. HOWEVER...LOCALIZED FLOODING
CANNOT BE COMPLETELY RULED OUT. CLOUD COVER AND SHOWERS WILL
CONTINUE TO BRING COOLER THAN NORMAL AFTERNOON HIGHS AND MOS
GUIDANCE SEEMED TO CAPTURE THIS WELL.

THE UPPER LOW OVER SOUTHERN CALIFORNIA WILL BEGIN TO WEAKEN AND
SHIFT INLAND LATE TONIGHT THROUGH THU. THIS KEEPS THE AREA UNDER
A SOUTH-SOUTHWEST FLOW. WHILE THIS FLOW REGIME IS FAVORABLE FOR
KEEPING THE SUB-TROPICAL TAP OPEN...IT DOES LOOK LIKE THERE WILL
BE A MODEST DOWNTURN IN MOISTURE THROUGH THURSDAY. PWAT VALUES
WILL BE MOSTLY BETWEEN HALF AND THREE QUARTERS INCH. AFTER THE
DIURNAL ACTIVITY DIMINISHES THIS EVENING...EXPECT A FEW NOCTURNAL
SHOWERS AND THUNDERSTORMS OVERNIGHT TONIGHT. THEN WITH DAYTIME
HEATING ON THU...MOSTLY SCATTERED SHOWERS AND THUNDERSTORMS WILL
DEVELOP IN THE AFTERNOON FOR THE MOUNTAINS...WITH LESS COVERAGE
IN THE VALLEYS.

.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 357 AM MDT WED AUG 20 2014

THERE ARE STILL SOME DIFFERENCES IN THE TIMING OF WHEN THE
WEAKENED SOUTHERN CALIFORNIA LOW WILL PASS OVER THE AREA. THE
FASTER GFS SHOWS IT OVER THE FOUR CORNERS AT 12Z/6AM MDT
FRI...WITH THE NAM/EC ABOUT 9-12 HOURS LATER. MODELS ALSO
INDICATED THAT SOME MOISTURE FROM TROPICAL STORM LOWELL COULD GET
ENTRAINED IN THE SOUTHWEST FLOW AHEAD OF THE LOW. ESPECIALLY IF
THE GFS VERIFIES...THU NIGHT COULD BE RELATIVELY ACTIVE WITH
NIGHTTIME CONVECTION INCREASING AFTER MIDNIGHT. BUT EVEN THE
SLOWER NAM/EC SOLUTIONS WOULD ENHANCE INSTABILITY TOWARDS MORNING.
THEN DAYTIME HEATING WILL ADD TO THE MIX ON FRI...FOR BETTER
AFTERNOON SHOWERS AND THUNDERSTORMS. TEMPERATURES WILL REMAIN
BELOW NORMAL.

THE UNSEASONABLE LONG-WAVE TROUGH REMAINS OVER THE ROCKIES FROM
SATURDAY INTO TUESDAY WITH A SERIES OF SHORTWAVES MOVING THROUGH
DURING THIS TIME FRAME. LITTLE SKILL IN TIMING OF THOSE
DISTURBANCES THIS FAR OUT...SO WILL CONTINUE TO FORECAST MAINLY
DIURNAL SHOWERS AND THUNDERSTORMS...FAVORING THE MOUNTAINS...THIS
WEEKEND THROUGH EARLY NEXT WEEK. MOISTURE DEPTH AND STORM MOTION
NOT FAVORABLE FOR SIGNIFICANT HEAVY RAIN. STAGNANT PATTERN FAVORS
LITTLE CHANGE IN TEMPERATURES WHICH SHOULD REMAIN COOL DURING
THIS PERIOD.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 357 AM MDT WED AUG 20 2014

A DISTURBANCE SWEEPING ACROSS THE NORTH WILL CONTINUE TO GENERATE
SHOWERS OVER NORTHWEST COLORADO NORTH OF THE I-70 CORRIDOR EARLY
THIS MORNING. AS TEMPERATURES RISE A FEW EMBEDDED THUNDERSTORMS
WILL DEVELOP FROM 15Z TO 18Z. COVERAGE AND INTENSITY OF STORMS
INCREASES THIS AFTERNOON AS TEMPERATURES REACH THEIR PEAK.
MOUNTAINS WILL BE OBSCURED AT TIMES. TAF SITES ALONG THE I-70
CORRIDOR FACE A GOOD CHANCE FOR THUNDERSTORM ACTIVITY WITH BRIEF
MVFR/IFR VSBY POSSIBLE IN HEAVY RAIN. THERE IS ONLY A SLIGHT
CHANCE THAT THE REMAINDER OF THE TAF SITES WILL BE DIRECTLY
IMPACTED BY THUNDERSTORMS...THOUGH THERE IS A GOOD CHANCE THAT
THUNDERSTORMS WILL BE IN THE VICINITY THROUGHOUT THE AFTERNOON AND
INTO THE EVENING. SHOWERS AND THUNDERSTORMS WILL LARGELY DIMINISH
THIS EVENING WITH VFR CONDITIONS RETURNING REGION WIDE.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

SHORT TERM...NL/EH
LONG TERM...EH/NL
AVIATION...NL





000
FXUS65 KGJT 200957
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
357 AM MDT WED AUG 20 2014

.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 357 AM MDT WED AUG 20 2014

LIGHT SHOWERS CONTINUED OVER PORTIONS OF CENTRAL AND NORTHWEST
COLORADO AND NORTHEAST UTAH EARLY THIS MORNING. LIFT ASSOCIATED
WITH THE LEFT EXIT REGION OF A JET STREAK ON THE EASTERN SIDE OF
A CLOSED LOW CIRCULATION OFF THE SOUTHERN CALIFORNIA COAST
APPEARED TO BE RESPONSIBLE FOR SUSTAINING MOIST CONVECTION.

THE INFLUENCE OF JET LEVEL DIVERGENCE DIMINISHES LATE TONIGHT INTO
WEDNESDAY MORNING. THEREAFTER...A SHORTWAVE WHICH WAS OVER WEST-
CENTRAL UTAH EARLY THIS MORNING WILL BECOME ENTRAINED IN THE
NORTHERLY STREAM...MOVING ACROSS NORTHEAST UTAH INTO NORTHWEST
COLORADO THIS MORNING. CONSEQUENTLY...SHOWERS AND EMBEDDED
THUNDERSTORMS WILL BE FAVORED ACROSS THE NORTH BEFORE NOON. A
MORE SHEARED SECONDARY WAVE WILL MOVE ALONG THE NORTHERN BORDER
AREA DURING THE AFTERNOON CONTINUING TO FOCUS SHOWERS AND
THUNDERSTORMS ACROSS THAT PORTION OF THE FORECAST AREA.

ELSEWHERE...DAYTIME WARMING WILL SPARK SCATTERED SHOWERS AND
THUNDERSTORMS...MAINLY OVER THE HIGHER TERRAIN. CLOUD COVER WILL
REMAIN PRETTY EXPANSIVE LIMITING INSOLATION AND IN TURN...STORM
STRENGTH. PRECIPITABLE WATER VALUES WILL BE FALLING BELOW AN INCH
AS DRIER MID-LEVEL FLOW MOVES IN. THIS...COMBINED WITH STEERING
WINDS STILL AVERAGING NEAR 20 KTS WILL LIMIT THE THREAT OF
EXCESSIVE RAINFALL AND FLOODING. HOWEVER...LOCALIZED FLOODING
CANNOT BE COMPLETELY RULED OUT. CLOUD COVER AND SHOWERS WILL
CONTINUE TO BRING COOLER THAN NORMAL AFTERNOON HIGHS AND MOS
GUIDANCE SEEMED TO CAPTURE THIS WELL.

THE UPPER LOW OVER SOUTHERN CALIFORNIA WILL BEGIN TO WEAKEN AND
SHIFT INLAND LATE TONIGHT THROUGH THU. THIS KEEPS THE AREA UNDER
A SOUTH-SOUTHWEST FLOW. WHILE THIS FLOW REGIME IS FAVORABLE FOR
KEEPING THE SUB-TROPICAL TAP OPEN...IT DOES LOOK LIKE THERE WILL
BE A MODEST DOWNTURN IN MOISTURE THROUGH THURSDAY. PWAT VALUES
WILL BE MOSTLY BETWEEN HALF AND THREE QUARTERS INCH. AFTER THE
DIURNAL ACTIVITY DIMINISHES THIS EVENING...EXPECT A FEW NOCTURNAL
SHOWERS AND THUNDERSTORMS OVERNIGHT TONIGHT. THEN WITH DAYTIME
HEATING ON THU...MOSTLY SCATTERED SHOWERS AND THUNDERSTORMS WILL
DEVELOP IN THE AFTERNOON FOR THE MOUNTAINS...WITH LESS COVERAGE
IN THE VALLEYS.

.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 357 AM MDT WED AUG 20 2014

THERE ARE STILL SOME DIFFERENCES IN THE TIMING OF WHEN THE
WEAKENED SOUTHERN CALIFORNIA LOW WILL PASS OVER THE AREA. THE
FASTER GFS SHOWS IT OVER THE FOUR CORNERS AT 12Z/6AM MDT
FRI...WITH THE NAM/EC ABOUT 9-12 HOURS LATER. MODELS ALSO
INDICATED THAT SOME MOISTURE FROM TROPICAL STORM LOWELL COULD GET
ENTRAINED IN THE SOUTHWEST FLOW AHEAD OF THE LOW. ESPECIALLY IF
THE GFS VERIFIES...THU NIGHT COULD BE RELATIVELY ACTIVE WITH
NIGHTTIME CONVECTION INCREASING AFTER MIDNIGHT. BUT EVEN THE
SLOWER NAM/EC SOLUTIONS WOULD ENHANCE INSTABILITY TOWARDS MORNING.
THEN DAYTIME HEATING WILL ADD TO THE MIX ON FRI...FOR BETTER
AFTERNOON SHOWERS AND THUNDERSTORMS. TEMPERATURES WILL REMAIN
BELOW NORMAL.

THE UNSEASONABLE LONG-WAVE TROUGH REMAINS OVER THE ROCKIES FROM
SATURDAY INTO TUESDAY WITH A SERIES OF SHORTWAVES MOVING THROUGH
DURING THIS TIME FRAME. LITTLE SKILL IN TIMING OF THOSE
DISTURBANCES THIS FAR OUT...SO WILL CONTINUE TO FORECAST MAINLY
DIURNAL SHOWERS AND THUNDERSTORMS...FAVORING THE MOUNTAINS...THIS
WEEKEND THROUGH EARLY NEXT WEEK. MOISTURE DEPTH AND STORM MOTION
NOT FAVORABLE FOR SIGNIFICANT HEAVY RAIN. STAGNANT PATTERN FAVORS
LITTLE CHANGE IN TEMPERATURES WHICH SHOULD REMAIN COOL DURING
THIS PERIOD.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 357 AM MDT WED AUG 20 2014

A DISTURBANCE SWEEPING ACROSS THE NORTH WILL CONTINUE TO GENERATE
SHOWERS OVER NORTHWEST COLORADO NORTH OF THE I-70 CORRIDOR EARLY
THIS MORNING. AS TEMPERATURES RISE A FEW EMBEDDED THUNDERSTORMS
WILL DEVELOP FROM 15Z TO 18Z. COVERAGE AND INTENSITY OF STORMS
INCREASES THIS AFTERNOON AS TEMPERATURES REACH THEIR PEAK.
MOUNTAINS WILL BE OBSCURED AT TIMES. TAF SITES ALONG THE I-70
CORRIDOR FACE A GOOD CHANCE FOR THUNDERSTORM ACTIVITY WITH BRIEF
MVFR/IFR VSBY POSSIBLE IN HEAVY RAIN. THERE IS ONLY A SLIGHT
CHANCE THAT THE REMAINDER OF THE TAF SITES WILL BE DIRECTLY
IMPACTED BY THUNDERSTORMS...THOUGH THERE IS A GOOD CHANCE THAT
THUNDERSTORMS WILL BE IN THE VICINITY THROUGHOUT THE AFTERNOON AND
INTO THE EVENING. SHOWERS AND THUNDERSTORMS WILL LARGELY DIMINISH
THIS EVENING WITH VFR CONDITIONS RETURNING REGION WIDE.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

SHORT TERM...NL/EH
LONG TERM...EH/NL
AVIATION...NL




000
FXUS65 KGJT 200434
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1034 PM MDT TUE AUG 19 2014

.UPDATE...
ISSUED AT 947 PM MDT TUE AUG 19 2014

MAINLY STRATIFORM PRECIPITATION CONTINUES THIS EVENING WITH A FEW
RUMBLES OF THUNDER THANKS TO EMBEDDED CONVECTION. LATEST NAM12 RUN
NOT INTIALIZING WELL...NOR IS THE GFS WITH BOTH SHOWING WIDESPREAD
AND HEAVY PRECIP OVERNIGHT WHILE HRRR IS CAPTURING PRECIP IN OUR
AREA PRETTY WELL. HRRR ALSO SHOWS SOME SHOWERY ACTIVITY
CONTINUING OVERNIGHT BUT COVERAGE IS ISOLATED AT BEST. LOOKING
UPSTREAM...RADAR MOSAIC SHOWING CONVECTION OVER EXTREME WRN UT/ERN
NV WITH NOT MUCH IN BETWEEN. IR IMAGERY IS ALSO SHOWING WARMING
CLOUD TOPS ACROSS OUR CWA INDICATING STRONGEST CONVECTION HAVING
ENDED. DO HAVE SOME CONCERN THAT UPPER LEVEL JET MOVING OVERHEAD
MAY FIRE OFF MORE CONVECTION OVERNIGHT BUT WITH DIVERGENCE
WEAKENING...WILL GO WITH MORE SCT TO ISOLD COVERAGE.

&&

.SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT)
ISSUED AT 344 PM MDT TUE AUG 19 2014

CURRENT IR SATELLITE SHOWS TWO PRECIPITATION HOT SPOTS - ONE WEST
OF VERNAL AND THE OTHER DOWN BY THE FOUR CORNERS. RADAR RETURNS
SHOW THE OUTER PERIPHERY OF THE ENHANCEMENT AT BLANDING UTAH AT
315PM. THIS RAIN WILL EXPAND TO THE NORTHEAST THROUGH THE LATE
AFTERNOON AND EVENING AS PRECIPITABLE WATER VALUES REACH THEIR
MAXIMUM OF ONE INCH TO 1.2 INCHES ACROSS THE REGION. A SERIES OF
H5 VORT MAXES ALONG WITH AN APPROACHING H3 50KT JET WILL MOVE
INTO THE AREA THIS EVENING...HELPING TO SUSTAIN SHOWERS AND
OCCASIONAL EMBEDDED THUNDERSTORMS. STORM MOTION STILL LOOKS TO BE
20 TO 30 KTS WITH MINIMAL TRAINING OCCURRING SO FAR.

SOME SUBSIDENCE OVER THE REGION TOMORROW WILL HINDER HIGH
LIKELIHOOD OF SHOWERS AND THUNDERSTORMS...HOWEVER FORECAST CIN IS
LOW OR NONEXISTENT BY THE AFTERNOON...AND AMPLE MOISTURE AND
BREAKS IN THE CLOUDS WILL BE IN PLACE TO INITIATE
ISOLATED/SCATTERED CONVECTION IN THE AFTERNOON. STEERING FLOW WILL
SLOW BY MIDDAY TO 10 TO 15 KTS. EXPECTING ACTIVITY TO OCCUR
EARLIER IN THE AFTERNOON AND TAPER OFF FOR THE MOST PART IN THE
EVENING.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 344 PM MDT TUE AUG 19 2014

WEATHER THE LAST HALF OF THE WEEK DEPENDS LARGELY ON THE UPPER LOW
CURRENTLY DROPPING SOUTH ALONG THE CA COAST. MODELS CONTINUE TO
HAVE SOME DIFFICULTY HANDLING THIS LOW. THE GFS REMAINS THE MOST
PROGRESSIVE...SWINGING IT IN INLAND ACROSS SRN CA THU AND UP
THROUGH ERN UT/WRN CO THU NIGHT. THE NAM AND ECMWF ARE SLOWER BY
ABOUT 12-24 HRS ON A TRACK A LITTLE FARTHER SOUTH. NUDGED POPS
UPWARD THU-FRI BUT REMAINED CONSERVATIVE DUE TO THE TIMING
DIFFERENCES.

SOME STORMS COULD BE RATHER STRONG THU-FRI GIVEN THAT THE DEEP LAYER
Q-G FORCING MAXIMA MOVES ACROSS THE AREA...AND 0-6KM VERTICAL WIND
SHEAR INCREASES WITH TROUGH PASSAGE...REGARDLESS OF MODEL. MODELS
ALSO HINT AT BRIEF ENTRAINMENT OF SOME MOISTURE FROM TROPICAL
STORM LOWELL...REFLECTED MORE IN THE 320K/325K ISENTROPIC SURFACE
HUMIDITY THAN PRECIPITABLE WATER FORECAST.

CONCURRENTLY...SHORTWAVE ENERGY SHARPENS AN UPPER TROUGH OVER THE
PAC NW AND NRN ROCKIES LATE IN THE WEEK. THIS TROUGH THEN SLOWLY
MIGRATES EASTWARD TO THE NORTHERN PLAINS AND SOUTHERN CANADA BY
MONDAY AFTERNOON. THIS SHOULD RESULT IN SOMEWHAT DRIER WESTERLY FLOW
ACROSS OUR AREA BY SUNDAY FOR A DOWNTURN IN SHOWER AND STORM
ACTIVITY THIS WEEKEND THROUGH EARLY NEXT WEEK.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 947 PM MDT TUE AUG 19 2014

-RA BEING REPORTED ALONG AND N OF I-70 THIS EVENING WITH KRIL
COMING IN WITH SOME MVFR CIGS WHILE REMAINING TAF SITES REPORTING
CIGS AROUND 6 TO 7K. AS THIS PRECIP CONTINUES SHIFTING TO THE NE...VFR
CONDITIONS ARE EXPECTED WITH BKN TO OVC SKIES. LATEST GUIDANCE
SHOWING MORE OF A DOWN DAY TOMORROW WITH SOME ISOLD CONVECTION TO
CONTEND WITH ACROSS THE CWA WITH MTN TAF SITES AND POSSIBLY SOME
VALLEY SITES SEEING SOME -RA...VCTS...OR A PASSING -TSRA.

&&

.HYDROLOGY...
ISSUED AT 344 PM MDT TUE AUG 19 2014

MONSOONAL MOISTURE IS RETURNING THIS EVENING AS AN UPPER LEVEL
LOW OVER CALIFORNIA PULLS DEEP SUBTROPICAL MOISTURE INTO THE
REGION. SHOWERS AND THUNDERSTORMS WILL INCREASE IN COVERAGE FROM
WEST TO EAST THIS EVENING...PEAKING THIS EVENING THEN CONTINUING
OVERNIGHT INTO WEDNESDAY MORNING. EXPECT SOME SMALL STREAM AND
ARROYO FLOOD ISSUES BY WEDNESDAY MORNING IN THE USUAL PROBLEM
AREAS. HOWEVER...DO NOT EXPECT SUFFICIENTLY WIDESPREAD COVERAGE OF
TORRENTIAL DOWNPOURS TO WARRANT FLASH FLOOD WATCH.

&&

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

$$

UPDATE...TGR
SHORT TERM...JAM
LONG TERM...JAD
AVIATION...TGR
HYDROLOGY...NL/JAM




000
FXUS65 KGJT 200434
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1034 PM MDT TUE AUG 19 2014

.UPDATE...
ISSUED AT 947 PM MDT TUE AUG 19 2014

MAINLY STRATIFORM PRECIPITATION CONTINUES THIS EVENING WITH A FEW
RUMBLES OF THUNDER THANKS TO EMBEDDED CONVECTION. LATEST NAM12 RUN
NOT INTIALIZING WELL...NOR IS THE GFS WITH BOTH SHOWING WIDESPREAD
AND HEAVY PRECIP OVERNIGHT WHILE HRRR IS CAPTURING PRECIP IN OUR
AREA PRETTY WELL. HRRR ALSO SHOWS SOME SHOWERY ACTIVITY
CONTINUING OVERNIGHT BUT COVERAGE IS ISOLATED AT BEST. LOOKING
UPSTREAM...RADAR MOSAIC SHOWING CONVECTION OVER EXTREME WRN UT/ERN
NV WITH NOT MUCH IN BETWEEN. IR IMAGERY IS ALSO SHOWING WARMING
CLOUD TOPS ACROSS OUR CWA INDICATING STRONGEST CONVECTION HAVING
ENDED. DO HAVE SOME CONCERN THAT UPPER LEVEL JET MOVING OVERHEAD
MAY FIRE OFF MORE CONVECTION OVERNIGHT BUT WITH DIVERGENCE
WEAKENING...WILL GO WITH MORE SCT TO ISOLD COVERAGE.

&&

.SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT)
ISSUED AT 344 PM MDT TUE AUG 19 2014

CURRENT IR SATELLITE SHOWS TWO PRECIPITATION HOT SPOTS - ONE WEST
OF VERNAL AND THE OTHER DOWN BY THE FOUR CORNERS. RADAR RETURNS
SHOW THE OUTER PERIPHERY OF THE ENHANCEMENT AT BLANDING UTAH AT
315PM. THIS RAIN WILL EXPAND TO THE NORTHEAST THROUGH THE LATE
AFTERNOON AND EVENING AS PRECIPITABLE WATER VALUES REACH THEIR
MAXIMUM OF ONE INCH TO 1.2 INCHES ACROSS THE REGION. A SERIES OF
H5 VORT MAXES ALONG WITH AN APPROACHING H3 50KT JET WILL MOVE
INTO THE AREA THIS EVENING...HELPING TO SUSTAIN SHOWERS AND
OCCASIONAL EMBEDDED THUNDERSTORMS. STORM MOTION STILL LOOKS TO BE
20 TO 30 KTS WITH MINIMAL TRAINING OCCURRING SO FAR.

SOME SUBSIDENCE OVER THE REGION TOMORROW WILL HINDER HIGH
LIKELIHOOD OF SHOWERS AND THUNDERSTORMS...HOWEVER FORECAST CIN IS
LOW OR NONEXISTENT BY THE AFTERNOON...AND AMPLE MOISTURE AND
BREAKS IN THE CLOUDS WILL BE IN PLACE TO INITIATE
ISOLATED/SCATTERED CONVECTION IN THE AFTERNOON. STEERING FLOW WILL
SLOW BY MIDDAY TO 10 TO 15 KTS. EXPECTING ACTIVITY TO OCCUR
EARLIER IN THE AFTERNOON AND TAPER OFF FOR THE MOST PART IN THE
EVENING.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 344 PM MDT TUE AUG 19 2014

WEATHER THE LAST HALF OF THE WEEK DEPENDS LARGELY ON THE UPPER LOW
CURRENTLY DROPPING SOUTH ALONG THE CA COAST. MODELS CONTINUE TO
HAVE SOME DIFFICULTY HANDLING THIS LOW. THE GFS REMAINS THE MOST
PROGRESSIVE...SWINGING IT IN INLAND ACROSS SRN CA THU AND UP
THROUGH ERN UT/WRN CO THU NIGHT. THE NAM AND ECMWF ARE SLOWER BY
ABOUT 12-24 HRS ON A TRACK A LITTLE FARTHER SOUTH. NUDGED POPS
UPWARD THU-FRI BUT REMAINED CONSERVATIVE DUE TO THE TIMING
DIFFERENCES.

SOME STORMS COULD BE RATHER STRONG THU-FRI GIVEN THAT THE DEEP LAYER
Q-G FORCING MAXIMA MOVES ACROSS THE AREA...AND 0-6KM VERTICAL WIND
SHEAR INCREASES WITH TROUGH PASSAGE...REGARDLESS OF MODEL. MODELS
ALSO HINT AT BRIEF ENTRAINMENT OF SOME MOISTURE FROM TROPICAL
STORM LOWELL...REFLECTED MORE IN THE 320K/325K ISENTROPIC SURFACE
HUMIDITY THAN PRECIPITABLE WATER FORECAST.

CONCURRENTLY...SHORTWAVE ENERGY SHARPENS AN UPPER TROUGH OVER THE
PAC NW AND NRN ROCKIES LATE IN THE WEEK. THIS TROUGH THEN SLOWLY
MIGRATES EASTWARD TO THE NORTHERN PLAINS AND SOUTHERN CANADA BY
MONDAY AFTERNOON. THIS SHOULD RESULT IN SOMEWHAT DRIER WESTERLY FLOW
ACROSS OUR AREA BY SUNDAY FOR A DOWNTURN IN SHOWER AND STORM
ACTIVITY THIS WEEKEND THROUGH EARLY NEXT WEEK.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 947 PM MDT TUE AUG 19 2014

-RA BEING REPORTED ALONG AND N OF I-70 THIS EVENING WITH KRIL
COMING IN WITH SOME MVFR CIGS WHILE REMAINING TAF SITES REPORTING
CIGS AROUND 6 TO 7K. AS THIS PRECIP CONTINUES SHIFTING TO THE NE...VFR
CONDITIONS ARE EXPECTED WITH BKN TO OVC SKIES. LATEST GUIDANCE
SHOWING MORE OF A DOWN DAY TOMORROW WITH SOME ISOLD CONVECTION TO
CONTEND WITH ACROSS THE CWA WITH MTN TAF SITES AND POSSIBLY SOME
VALLEY SITES SEEING SOME -RA...VCTS...OR A PASSING -TSRA.

&&

.HYDROLOGY...
ISSUED AT 344 PM MDT TUE AUG 19 2014

MONSOONAL MOISTURE IS RETURNING THIS EVENING AS AN UPPER LEVEL
LOW OVER CALIFORNIA PULLS DEEP SUBTROPICAL MOISTURE INTO THE
REGION. SHOWERS AND THUNDERSTORMS WILL INCREASE IN COVERAGE FROM
WEST TO EAST THIS EVENING...PEAKING THIS EVENING THEN CONTINUING
OVERNIGHT INTO WEDNESDAY MORNING. EXPECT SOME SMALL STREAM AND
ARROYO FLOOD ISSUES BY WEDNESDAY MORNING IN THE USUAL PROBLEM
AREAS. HOWEVER...DO NOT EXPECT SUFFICIENTLY WIDESPREAD COVERAGE OF
TORRENTIAL DOWNPOURS TO WARRANT FLASH FLOOD WATCH.

&&

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

$$

UPDATE...TGR
SHORT TERM...JAM
LONG TERM...JAD
AVIATION...TGR
HYDROLOGY...NL/JAM





000
FXUS65 KGJT 192338
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
538 PM MDT TUE AUG 19 2014

.SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT)
ISSUED AT 344 PM MDT TUE AUG 19 2014

CURRENT IR SATELLITE SHOWS TWO PRECIPITATION HOT SPOTS - ONE WEST
OF VERNAL AND THE OTHER DOWN BY THE FOUR CORNERS. RADAR RETURNS
SHOW THE OUTER PERIPHERY OF THE ENHANCEMENT AT BLANDING UTAH AT
315PM. THIS RAIN WILL EXPAND TO THE NORTHEAST THROUGH THE LATE
AFTERNOON AND EVENING AS PRECIPITABLE WATER VALUES REACH THEIR
MAXIMUM OF ONE INCH TO 1.2 INCHES ACROSS THE REGION. A SERIES OF
H5 VORT MAXES ALONG WITH AN APPROACHING H3 50KT JET WILL MOVE
INTO THE AREA THIS EVENING...HELPING TO SUSTAIN SHOWERS AND
OCCASIONAL EMBEDDED THUNDERSTORMS. STORM MOTION STILL LOOKS TO BE
20 TO 30 KTS WITH MINIMAL TRAINING OCCURRING SO FAR.

SOME SUBSIDENCE OVER THE REGION TOMORROW WILL HINDER HIGH
LIKELIHOOD OF SHOWERS AND THUNDERSTORMS...HOWEVER FORECAST CIN IS
LOW OR NONEXISTENT BY THE AFTERNOON...AND AMPLE MOISTURE AND
BREAKS IN THE CLOUDS WILL BE IN PLACE TO INITIATE
ISOLATED/SCATTERED CONVECTION IN THE AFTERNOON. STEERING FLOW WILL
SLOW BY MIDDAY TO 10 TO 15 KTS. EXPECTING ACTIVITY TO OCCUR
EARLIER IN THE AFTERNOON AND TAPER OFF FOR THE MOST PART IN THE
EVENING.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 344 PM MDT TUE AUG 19 2014

WEATHER THE LAST HALF OF THE WEEK DEPENDS LARGELY ON THE UPPER LOW
CURRENTLY DROPPING SOUTH ALONG THE CA COAST. MODELS CONTINUE TO
HAVE SOME DIFFICULTY HANDLING THIS LOW. THE GFS REMAINS THE MOST
PROGRESSIVE...SWINGING IT IN INLAND ACROSS SRN CA THU AND UP
THROUGH ERN UT/WRN CO THU NIGHT. THE NAM AND ECMWF ARE SLOWER BY
ABOUT 12-24 HRS ON A TRACK A LITTLE FARTHER SOUTH. NUDGED POPS
UPWARD THU-FRI BUT REMAINED CONSERVATIVE DUE TO THE TIMING
DIFFERENCES.

SOME STORMS COULD BE RATHER STRONG THU-FRI GIVEN THAT THE DEEP LAYER
Q-G FORCING MAXIMA MOVES ACROSS THE AREA...AND 0-6KM VERTICAL WIND
SHEAR INCREASES WITH TROUGH PASSAGE...REGARDLESS OF MODEL. MODELS
ALSO HINT AT BRIEF ENTRAINMENT OF SOME MOISTURE FROM TROPICAL
STORM LOWELL...REFLECTED MORE IN THE 320K/325K ISENTROPIC SURFACE
HUMIDITY THAN PRECIPITABLE WATER FORECAST.

CONCURRENTLY...SHORTWAVE ENERGY SHARPENS AN UPPER TROUGH OVER THE
PAC NW AND NRN ROCKIES LATE IN THE WEEK. THIS TROUGH THEN SLOWLY
MIGRATES EASTWARD TO THE NORTHERN PLAINS AND SOUTHERN CANADA BY
MONDAY AFTERNOON. THIS SHOULD RESULT IN SOMEWHAT DRIER WESTERLY FLOW
ACROSS OUR AREA BY SUNDAY FOR A DOWNTURN IN SHOWER AND STORM
ACTIVITY THIS WEEKEND THROUGH EARLY NEXT WEEK.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 530 PM MDT TUE AUG 19 2014

PLENTY OF RAIN AND STORMS CONTINUING THIS EVENING WITH ALL
AERODROMES POSSIBLY SEEING -RA OR -TSRA ON STATION. MODELS
CONTINUE TO SHOW PRECIP CONTINUING OVERNIGHT...EVEN INCREASING
AFTER 03Z BEFORE SLACKENING OFF SOME AFTER 12Z. EXPECT CONDITIONS
TO REMAIN THE SAME THEN THROUGH THIS EVENING INTO THE OVERNIGHT WITH
IFR/MVFR OCCURRING FROM TIME TO TIME DUE TO HEAVIER RAINFALL
DROPPING VISIBILITIES. THERE WILL BE OCCNL BREAKS BUT FLIGHT
CONDITIONS WILL BE AFFECTED FOR QUITE SOME TIME. MTN OBSCURATIONS
WILL ALSO OCCUR AS WILL OCCNL GUSTY SURFACE WINDS.

&&

.HYDROLOGY...
ISSUED AT 344 PM MDT TUE AUG 19 2014

MONSOONAL MOISTURE IS RETURNING THIS EVENING AS AN UPPER LEVEL
LOW OVER CALIFORNIA PULLS DEEP SUBTROPICAL MOISTURE INTO THE
REGION. SHOWERS AND THUNDERSTORMS WILL INCREASE IN COVERAGE FROM
WEST TO EAST THIS EVENING...PEAKING THIS EVENING THEN CONTINUING
OVERNIGHT INTO WEDNESDAY MORNING. EXPECT SOME SMALL STREAM AND
ARROYO FLOOD ISSUES BY WEDNESDAY MORNING IN THE USUAL PROBLEM
AREAS. HOWEVER...DO NOT EXPECT SUFFICIENTLY WIDESPREAD COVERAGE OF
TORRENTIAL DOWNPOURS TO WARRANT FLASH FLOOD WATCH.

&&

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

$$

SHORT TERM...JAM
LONG TERM...JAD
AVIATION...TGR
HYDROLOGY...NL/JAM




000
FXUS65 KGJT 192338
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
538 PM MDT TUE AUG 19 2014

.SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT)
ISSUED AT 344 PM MDT TUE AUG 19 2014

CURRENT IR SATELLITE SHOWS TWO PRECIPITATION HOT SPOTS - ONE WEST
OF VERNAL AND THE OTHER DOWN BY THE FOUR CORNERS. RADAR RETURNS
SHOW THE OUTER PERIPHERY OF THE ENHANCEMENT AT BLANDING UTAH AT
315PM. THIS RAIN WILL EXPAND TO THE NORTHEAST THROUGH THE LATE
AFTERNOON AND EVENING AS PRECIPITABLE WATER VALUES REACH THEIR
MAXIMUM OF ONE INCH TO 1.2 INCHES ACROSS THE REGION. A SERIES OF
H5 VORT MAXES ALONG WITH AN APPROACHING H3 50KT JET WILL MOVE
INTO THE AREA THIS EVENING...HELPING TO SUSTAIN SHOWERS AND
OCCASIONAL EMBEDDED THUNDERSTORMS. STORM MOTION STILL LOOKS TO BE
20 TO 30 KTS WITH MINIMAL TRAINING OCCURRING SO FAR.

SOME SUBSIDENCE OVER THE REGION TOMORROW WILL HINDER HIGH
LIKELIHOOD OF SHOWERS AND THUNDERSTORMS...HOWEVER FORECAST CIN IS
LOW OR NONEXISTENT BY THE AFTERNOON...AND AMPLE MOISTURE AND
BREAKS IN THE CLOUDS WILL BE IN PLACE TO INITIATE
ISOLATED/SCATTERED CONVECTION IN THE AFTERNOON. STEERING FLOW WILL
SLOW BY MIDDAY TO 10 TO 15 KTS. EXPECTING ACTIVITY TO OCCUR
EARLIER IN THE AFTERNOON AND TAPER OFF FOR THE MOST PART IN THE
EVENING.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 344 PM MDT TUE AUG 19 2014

WEATHER THE LAST HALF OF THE WEEK DEPENDS LARGELY ON THE UPPER LOW
CURRENTLY DROPPING SOUTH ALONG THE CA COAST. MODELS CONTINUE TO
HAVE SOME DIFFICULTY HANDLING THIS LOW. THE GFS REMAINS THE MOST
PROGRESSIVE...SWINGING IT IN INLAND ACROSS SRN CA THU AND UP
THROUGH ERN UT/WRN CO THU NIGHT. THE NAM AND ECMWF ARE SLOWER BY
ABOUT 12-24 HRS ON A TRACK A LITTLE FARTHER SOUTH. NUDGED POPS
UPWARD THU-FRI BUT REMAINED CONSERVATIVE DUE TO THE TIMING
DIFFERENCES.

SOME STORMS COULD BE RATHER STRONG THU-FRI GIVEN THAT THE DEEP LAYER
Q-G FORCING MAXIMA MOVES ACROSS THE AREA...AND 0-6KM VERTICAL WIND
SHEAR INCREASES WITH TROUGH PASSAGE...REGARDLESS OF MODEL. MODELS
ALSO HINT AT BRIEF ENTRAINMENT OF SOME MOISTURE FROM TROPICAL
STORM LOWELL...REFLECTED MORE IN THE 320K/325K ISENTROPIC SURFACE
HUMIDITY THAN PRECIPITABLE WATER FORECAST.

CONCURRENTLY...SHORTWAVE ENERGY SHARPENS AN UPPER TROUGH OVER THE
PAC NW AND NRN ROCKIES LATE IN THE WEEK. THIS TROUGH THEN SLOWLY
MIGRATES EASTWARD TO THE NORTHERN PLAINS AND SOUTHERN CANADA BY
MONDAY AFTERNOON. THIS SHOULD RESULT IN SOMEWHAT DRIER WESTERLY FLOW
ACROSS OUR AREA BY SUNDAY FOR A DOWNTURN IN SHOWER AND STORM
ACTIVITY THIS WEEKEND THROUGH EARLY NEXT WEEK.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 530 PM MDT TUE AUG 19 2014

PLENTY OF RAIN AND STORMS CONTINUING THIS EVENING WITH ALL
AERODROMES POSSIBLY SEEING -RA OR -TSRA ON STATION. MODELS
CONTINUE TO SHOW PRECIP CONTINUING OVERNIGHT...EVEN INCREASING
AFTER 03Z BEFORE SLACKENING OFF SOME AFTER 12Z. EXPECT CONDITIONS
TO REMAIN THE SAME THEN THROUGH THIS EVENING INTO THE OVERNIGHT WITH
IFR/MVFR OCCURRING FROM TIME TO TIME DUE TO HEAVIER RAINFALL
DROPPING VISIBILITIES. THERE WILL BE OCCNL BREAKS BUT FLIGHT
CONDITIONS WILL BE AFFECTED FOR QUITE SOME TIME. MTN OBSCURATIONS
WILL ALSO OCCUR AS WILL OCCNL GUSTY SURFACE WINDS.

&&

.HYDROLOGY...
ISSUED AT 344 PM MDT TUE AUG 19 2014

MONSOONAL MOISTURE IS RETURNING THIS EVENING AS AN UPPER LEVEL
LOW OVER CALIFORNIA PULLS DEEP SUBTROPICAL MOISTURE INTO THE
REGION. SHOWERS AND THUNDERSTORMS WILL INCREASE IN COVERAGE FROM
WEST TO EAST THIS EVENING...PEAKING THIS EVENING THEN CONTINUING
OVERNIGHT INTO WEDNESDAY MORNING. EXPECT SOME SMALL STREAM AND
ARROYO FLOOD ISSUES BY WEDNESDAY MORNING IN THE USUAL PROBLEM
AREAS. HOWEVER...DO NOT EXPECT SUFFICIENTLY WIDESPREAD COVERAGE OF
TORRENTIAL DOWNPOURS TO WARRANT FLASH FLOOD WATCH.

&&

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

$$

SHORT TERM...JAM
LONG TERM...JAD
AVIATION...TGR
HYDROLOGY...NL/JAM





000
FXUS65 KGJT 192144
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
344 PM MDT TUE AUG 19 2014

.SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT)
ISSUED AT 344 PM MDT TUE AUG 19 2014

CURRENT IR SATELLITE SHOWS TWO PRECIPITATION HOT SPOTS - ONE WEST
OF VERNAL AND THE OTHER DOWN BY THE FOUR CORNERS. RADAR RETURNS
SHOW THE OUTER PERIPHERY OF THE ENHANCEMENT AT BLANDING UTAH AT
315PM. THIS RAIN WILL EXPAND TO THE NORTHEAST THROUGH THE LATE
AFTERNOON AND EVENING AS PRECIPITABLE WATER VALUES REACH THEIR
MAXIMUM OF ONE INCH TO 1.2 INCHES ACROSS THE REGION. A SERIES OF
H5 VORT MAXES ALONG WITH AN APPROACHING H3 50KT JET WILL MOVE
INTO THE AREA THIS EVENING...HELPING TO SUSTAIN SHOWERS AND
OCCASIONAL EMBEDDED THUNDERSTORMS. STORM MOTION STILL LOOKS TO BE
20 TO 30 KTS WITH MINIMAL TRAINING OCCURRING SO FAR.

SOME SUBSIDENCE OVER THE REGION TOMORROW WILL HINDER HIGH
LIKELIHOOD OF SHOWERS AND THUNDERSTORMS...HOWEVER FORECAST CIN IS
LOW OR NONEXISTENT BY THE AFTERNOON...AND AMPLE MOISTURE AND
BREAKS IN THE CLOUDS WILL BE IN PLACE TO INITIATE
ISOLATED/SCATTERED CONVECTION IN THE AFTERNOON. STEERING FLOW WILL
SLOW BY MIDDAY TO 10 TO 15 KTS. EXPECTING ACTIVITY TO OCCUR
EARLIER IN THE AFTERNOON AND TAPER OFF FOR THE MOST PART IN THE
EVENING.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 344 PM MDT TUE AUG 19 2014

WEATHER THE LAST HALF OF THE WEEK DEPENDS LARGELY ON THE UPPER LOW
CURRENTLY DROPPING SOUTH ALONG THE CA COAST. MODELS CONTINUE TO
HAVE SOME DIFFICULTY HANDLING THIS LOW. THE GFS REMAINS THE MOST
PROGRESSIVE...SWINGING IT IN INLAND ACROSS SRN CA THU AND UP
THROUGH ERN UT/WRN CO THU NIGHT. THE NAM AND ECMWF ARE SLOWER BY
ABOUT 12-24 HRS ON A TRACK A LITTLE FARTHER SOUTH. NUDGED POPS
UPWARD THU-FRI BUT REMAINED CONSERVATIVE DUE TO THE TIMING
DIFFERENCES.

SOME STORMS COULD BE RATHER STRONG THU-FRI GIVEN THAT THE DEEP LAYER
Q-G FORCING MAXIMA MOVES ACROSS THE AREA...AND 0-6KM VERTICAL WIND
SHEAR INCREASES WITH TROUGH PASSAGE...REGARDLESS OF MODEL. MODELS
ALSO HINT AT BRIEF ENTRAINMENT OF SOME MOISTURE FROM TROPICAL
STORM LOWELL...REFLECTED MORE IN THE 320K/325K ISENTROPIC SURFACE
HUMIDITY THAN PRECIPITABLE WATER FORECAST.

CONCURRENTLY...SHORTWAVE ENERGY SHARPENS AN UPPER TROUGH OVER THE
PAC NW AND NRN ROCKIES LATE IN THE WEEK. THIS TROUGH THEN SLOWLY
MIGRATES EASTWARD TO THE NORTHERN PLAINS AND SOUTHERN CANADA BY
MONDAY AFTERNOON. THIS SHOULD RESULT IN SOMEWHAT DRIER WESTERLY FLOW
ACROSS OUR AREA BY SUNDAY FOR A DOWNTURN IN SHOWER AND STORM
ACTIVITY THIS WEEKEND THROUGH EARLY NEXT WEEK.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1055 AM MDT TUE AUG 19 2014

LIGHT TO MODERATE RAIN SHOWERS OVER NORTHWESTERN COLORADO WILL
CONTINUE TO MOVE NORTHEAST. VCSH IS MOST LIKELY AT
KRIL...KGJT...KASE...AND KEGE THROUGH 20Z. KCNY WILL HAVE ON AND
OFF SHOWERS THROUGH 19Z BUT THEN SHOULD GET A SHORT BREAK EARLY
THIS AFTERNOON. THE FOUR CORNERS WILL HAVE -SHRA AND -TSRA
POPPING UP BEGINNING AT ABOUT 18Z AND CONTINUING ON AND OFF
THROUGHOUT THE NEXT 18 HOURS OR SO. MONSOONAL WILL INCREASE
THROUGHOUT THE AFTERNOON SO THE ACTIVE WEATHER WILL BECOME MORE
WIDESPREAD AFTER 22Z FROM WEST TO EAST. RA AND TS WILL OBSCURE
MANY MOUNTAIN LOCATIONS UNTIL 12Z. STORMS WILL BE CAPABLE OF
PRODUCING MVFR/IFR VSBY IN HEAVY RAIN AT MANY TAF LOCATIONS OVER
THE NEXT 24 HOURS.


&&

.HYDROLOGY...
ISSUED AT 344 PM MDT TUE AUG 19 2014

MONSOONAL MOISTURE IS RETURNING THIS EVENING AS AN UPPER LEVEL
LOW OVER CALIFORNIA PULLS DEEP SUBTROPICAL MOISTURE INTO THE
REGION. SHOWERS AND THUNDERSTORMS WILL INCREASE IN COVERAGE FROM
WEST TO EAST THIS EVENING...PEAKING THIS EVENING THEN CONTINUING
OVERNIGHT INTO WEDNESDAY MORNING. EXPECT SOME SMALL STREAM AND
ARROYO FLOOD ISSUES BY WEDNESDAY MORNING IN THE USUAL PROBLEM
AREAS. HOWEVER...DO NOT EXPECT SUFFICIENTLY WIDESPREAD COVERAGE OF
TORRENTIAL DOWNPOURS TO WARRANT FLASH FLOOD WATCH.

&&

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

$$

SHORT TERM...JAM
LONG TERM...JAD
AVIATION...JAM
HYDROLOGY...NL/JAM





000
FXUS65 KGJT 192144
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
344 PM MDT TUE AUG 19 2014

.SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT)
ISSUED AT 344 PM MDT TUE AUG 19 2014

CURRENT IR SATELLITE SHOWS TWO PRECIPITATION HOT SPOTS - ONE WEST
OF VERNAL AND THE OTHER DOWN BY THE FOUR CORNERS. RADAR RETURNS
SHOW THE OUTER PERIPHERY OF THE ENHANCEMENT AT BLANDING UTAH AT
315PM. THIS RAIN WILL EXPAND TO THE NORTHEAST THROUGH THE LATE
AFTERNOON AND EVENING AS PRECIPITABLE WATER VALUES REACH THEIR
MAXIMUM OF ONE INCH TO 1.2 INCHES ACROSS THE REGION. A SERIES OF
H5 VORT MAXES ALONG WITH AN APPROACHING H3 50KT JET WILL MOVE
INTO THE AREA THIS EVENING...HELPING TO SUSTAIN SHOWERS AND
OCCASIONAL EMBEDDED THUNDERSTORMS. STORM MOTION STILL LOOKS TO BE
20 TO 30 KTS WITH MINIMAL TRAINING OCCURRING SO FAR.

SOME SUBSIDENCE OVER THE REGION TOMORROW WILL HINDER HIGH
LIKELIHOOD OF SHOWERS AND THUNDERSTORMS...HOWEVER FORECAST CIN IS
LOW OR NONEXISTENT BY THE AFTERNOON...AND AMPLE MOISTURE AND
BREAKS IN THE CLOUDS WILL BE IN PLACE TO INITIATE
ISOLATED/SCATTERED CONVECTION IN THE AFTERNOON. STEERING FLOW WILL
SLOW BY MIDDAY TO 10 TO 15 KTS. EXPECTING ACTIVITY TO OCCUR
EARLIER IN THE AFTERNOON AND TAPER OFF FOR THE MOST PART IN THE
EVENING.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 344 PM MDT TUE AUG 19 2014

WEATHER THE LAST HALF OF THE WEEK DEPENDS LARGELY ON THE UPPER LOW
CURRENTLY DROPPING SOUTH ALONG THE CA COAST. MODELS CONTINUE TO
HAVE SOME DIFFICULTY HANDLING THIS LOW. THE GFS REMAINS THE MOST
PROGRESSIVE...SWINGING IT IN INLAND ACROSS SRN CA THU AND UP
THROUGH ERN UT/WRN CO THU NIGHT. THE NAM AND ECMWF ARE SLOWER BY
ABOUT 12-24 HRS ON A TRACK A LITTLE FARTHER SOUTH. NUDGED POPS
UPWARD THU-FRI BUT REMAINED CONSERVATIVE DUE TO THE TIMING
DIFFERENCES.

SOME STORMS COULD BE RATHER STRONG THU-FRI GIVEN THAT THE DEEP LAYER
Q-G FORCING MAXIMA MOVES ACROSS THE AREA...AND 0-6KM VERTICAL WIND
SHEAR INCREASES WITH TROUGH PASSAGE...REGARDLESS OF MODEL. MODELS
ALSO HINT AT BRIEF ENTRAINMENT OF SOME MOISTURE FROM TROPICAL
STORM LOWELL...REFLECTED MORE IN THE 320K/325K ISENTROPIC SURFACE
HUMIDITY THAN PRECIPITABLE WATER FORECAST.

CONCURRENTLY...SHORTWAVE ENERGY SHARPENS AN UPPER TROUGH OVER THE
PAC NW AND NRN ROCKIES LATE IN THE WEEK. THIS TROUGH THEN SLOWLY
MIGRATES EASTWARD TO THE NORTHERN PLAINS AND SOUTHERN CANADA BY
MONDAY AFTERNOON. THIS SHOULD RESULT IN SOMEWHAT DRIER WESTERLY FLOW
ACROSS OUR AREA BY SUNDAY FOR A DOWNTURN IN SHOWER AND STORM
ACTIVITY THIS WEEKEND THROUGH EARLY NEXT WEEK.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1055 AM MDT TUE AUG 19 2014

LIGHT TO MODERATE RAIN SHOWERS OVER NORTHWESTERN COLORADO WILL
CONTINUE TO MOVE NORTHEAST. VCSH IS MOST LIKELY AT
KRIL...KGJT...KASE...AND KEGE THROUGH 20Z. KCNY WILL HAVE ON AND
OFF SHOWERS THROUGH 19Z BUT THEN SHOULD GET A SHORT BREAK EARLY
THIS AFTERNOON. THE FOUR CORNERS WILL HAVE -SHRA AND -TSRA
POPPING UP BEGINNING AT ABOUT 18Z AND CONTINUING ON AND OFF
THROUGHOUT THE NEXT 18 HOURS OR SO. MONSOONAL WILL INCREASE
THROUGHOUT THE AFTERNOON SO THE ACTIVE WEATHER WILL BECOME MORE
WIDESPREAD AFTER 22Z FROM WEST TO EAST. RA AND TS WILL OBSCURE
MANY MOUNTAIN LOCATIONS UNTIL 12Z. STORMS WILL BE CAPABLE OF
PRODUCING MVFR/IFR VSBY IN HEAVY RAIN AT MANY TAF LOCATIONS OVER
THE NEXT 24 HOURS.


&&

.HYDROLOGY...
ISSUED AT 344 PM MDT TUE AUG 19 2014

MONSOONAL MOISTURE IS RETURNING THIS EVENING AS AN UPPER LEVEL
LOW OVER CALIFORNIA PULLS DEEP SUBTROPICAL MOISTURE INTO THE
REGION. SHOWERS AND THUNDERSTORMS WILL INCREASE IN COVERAGE FROM
WEST TO EAST THIS EVENING...PEAKING THIS EVENING THEN CONTINUING
OVERNIGHT INTO WEDNESDAY MORNING. EXPECT SOME SMALL STREAM AND
ARROYO FLOOD ISSUES BY WEDNESDAY MORNING IN THE USUAL PROBLEM
AREAS. HOWEVER...DO NOT EXPECT SUFFICIENTLY WIDESPREAD COVERAGE OF
TORRENTIAL DOWNPOURS TO WARRANT FLASH FLOOD WATCH.

&&

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

$$

SHORT TERM...JAM
LONG TERM...JAD
AVIATION...JAM
HYDROLOGY...NL/JAM




000
FXUS65 KGJT 191659
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1059 AM MDT TUE AUG 19 2014

.UPDATE...
ISSUED AT 1055 AM MDT TUE AUG 19 2014

THE SHIELD OF RAIN SHOWERS IN NORTHWESTERN COLORADO WILL CONTINUE
TO MOVE TO THE NORTHEAST LATE THIS MORNING AND INTO THE EARLY
AFTERNOON. THERE ARE ALREADY SIGNS OF SHOWERS TRAINING IN EAST-
CENTRAL UTAH...AND THOSE RAINFALL RATES ARE LIGHT AT THIS
TIME...ANY RAIN THIS MORNING WILL HELP TO SATURATE THE GROUND FOR
THE HEAVIER RAIN EXPECTED LATER TODAY AND TONIGHT. PRECIPITATION
VALUES RECORDED HAVE GENERALLY BEEN LESS THAN A TENTH OF AN INCH
OVERNIGHT AND THIS MORNING.

FORECAST ON TRACK WITH CLOUD COVER OVER THE CWA KEEPING
STRONG SHOWERS/STORMS SUPPRESSED SO FAR. THERE IS SOME CLEARING
DOWN AT THE FOUR CORNERS WHICH WILL BE SUSCEPTIBLE TO STORMS
DEVELOPING DUE TO DAYTIME HEATING AS WE NEAR THE AFTERNOON.

&&

.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 345 AM MDT TUE AUG 19 2014

PER PREVIOUS DISCUSSION...MONSOONAL SURGE ONGOING EARLY THIS
MORNING WITH DEEP SUBTROPICAL MOISTURE CARRIED NORTHWARD INTO
THE REGION AHEAD OF A LOW PRESSURE SYSTEM OFF THE CENTRAL
CALIFORNIA COAST. A SHORTWAVE EJECTED FROM THE LOW WAS RESPONSIBLE
FOR SHOWERS AND A FEW EMBEDDED THUNDERSTORMS OVER THE SOUTHERN
PORTION OF THE FORECAST AREA EARLY THIS MORNING. CONTINUED MOIST
ADVECTION...DAYTIME WARMING AND THE NORTHWARD TRANSIT OF THE
SHORTWAVE WILL BRING INCREASED SHOWERS AND THUNDERSTORMS FROM LATE
MORNING THROUGH THE AFTERNOON. LATEST BUFR SOUNDINGS INDICATED
PRECIPITABLE WATER VALUES IN EXCESS OF 1 INCH ACROSS SOUTHEAST
UTAH AND EXTREME WEST-CENTRAL AND SOUTHWEST COLORADO THIS
AFTERNOON RAISING THE POTENTIAL FOR HEAVY RAIN. HOWEVER...CONCUR
WITH PREVIOUS FORECAST ASSESSMENT THAT FLASH FLOOD POTENTIAL
MITIGATED BY CLOUD COVER AND FAVORABLE STORM MOTION IN EXCESS OF
15 TO 25 MPH. THAT SAID...LOCALIZED HEAVY RAIN MAY STILL RESULT IN
LOCALIZED FLOODING. AS ALLUDED TO EARLIER...CLOUD COVER WILL KEEP
AFTERNOON HIGHS COOLER AS COMPARED TO YESTERDAY AVERAGING AROUND
10 DEGREES LOWER ON AVERAGE.

AN UNUSUAL SEASONAL CHANGE TO THE SYNOPTIC PATTERN AS THE
SUBTROPICAL RIDGE GETS SHUNTED TO THE GULF COAST AND A PACIFIC
TROUGH DOMINATES. TONIGHT DISORGANIZED ENERGY EJECTS OFF THE
SOUTHERN CALIFORNIA LOW WITH AN ASSOCIATED JET STREAK ORIENTED
SW-NE OVER NE UTAH. SOUTH OF THIS FEATURE MOISTURE IS IMPRESSIVE
ERODING FROM 1.2 INCHES TO AROUND AN INCH TOWARDS WEDNESDAY
MORNING. NOCTURNAL STORMS WILL BE PRODUCING HEAVY RAIN AT TIMES
BUT STORM MOTION WILL BE TO THE ENE AT 20KTS. THIS SPEED WILL
REQUIRE TRAINING OF WET CELLS TO PRODUCE FLOODING ISSUES. STILL
WHERE HEAVY RAIN FALLS TODAY WILL BE THE THREATENED AREAS FOR
POTENTIAL FLOODING TONIGHT. MOISTURE DECREASES TOWARDS THE NE SO
THE PARK/GORE/STEAMBOAT AREA LOOKS LESS LIKELY TO GET HEAVIER
SHOWERS. EVEN THERE THE POTENTIAL IS NOT ZERO. GUSTY STORM WINDS
WILL LIKELY BE WIDESPREAD WITH SMALL HAIL IN THE HOTTEST CELLS.

WEDNESDAY THE CALIFORNIA LOW WORKS OVER SAN DIEGO WITH A
DEFORMATION AXIS STRETCHED INTO NE UTAH AND BEYOND. MOISTURE
ERODES TO AROUND 0.75 INCH WHICH WILL PRODUCE SCATTERED LATE-DAY
CONVECTION. TEMPERATURES REMAIN WELL BELOW NORMAL.

.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 345 AM MDT TUE AUG 19 2014

AT THE SYNOPTIC SCALE THE MODELS ARE STILL NOT IN GOOD AGREEMENT
ON HOW TO HANDLE THE UNUSUAL FOR AUGUST WEST COAST TROUGH. TIMING
OF ITS SLOW PROGRESSION IS IN DOUBT. BUT THROUGH THURSDAY NIGHT WE
REMAIN IN A PERTURBED SW FLOW WITH A WEAK JET STREAK OVER UTAH.
PRECIP WATER VALUES REMAIN NEAR AN INCH IN THE FOUR CORNERS TO
AROUND 0.75 INCH FURTHER NORTH. THIS IS SUFFICIENT FOR SCATTERED
DIURNAL THUNDERSTORMS AND ISOLATED NOCTURNAL STORMS FAVORING THE
SOUTHERN ZONES. THE TROUGH AXIS APPROACHES THE REGION THURSDAY
NIGHT FOR ENHANCED DYNAMICAL SUPPORT AND PERHAPS INCREASED
NIGHTTIME THUNDERSTORMS. GUSTY WINDS AND SMALL HAIL REMAIN A
THREAT WITH STRONGER CELLS.

MODELS CONTINUED TO HANG ONTO LONGWAVE TROUGH OVER THE WEST
THROUGH THE REMAINDER OF THE WEEK. ECMWF DEVELOPS MORE OF A SPLIT
BY FRIDAY ALLOWING SUBTROPICAL MOISTURE TO CONTINUE TO MOVE INTO
THE AREA. THE TROUGH IN THE GFS WAS MORE COHERENT AND THUS FLOW
INDICATED TO BE MORE WESTERLY AND DRIER. REGARDLESS...BOTH
SOLUTIONS CONTAIN ENOUGH MOISTURE FOR DIURNAL SHOWERS AND
THUNDERSTORMS DURING THE LATTER PART OF THE WEEK. UNSETTLED
CONDITIONS LIKELY TO CONTINUE INTO THE WEEKEND. ECMWF NEAR
STAGNANT WITH VERY LITTLE CHANGE RELATIVE TO THAT DESCRIBED
EARLIER. MEANWHILE...GFS REMAINED MORE ZONAL. GIVEN POSITIONING
OF THE TROUGH...COMBINED WITH DAILY SHOWERS AND THUNDERSTORMS
...EXPECT TEMPERATURES WILL REMAIN BELOW NORMAL THURSDAY THROUGH
THE WEEKEND.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1055 AM MDT TUE AUG 19 2014

LIGHT TO MODERATE RAIN SHOWERS OVER NORTHWESTERN COLORADO WILL
CONTINUE TO MOVE NORTHEAST. VCSH IS MOST LIKELY AT
KRIL...KGJT...KASE...AND KEGE THROUGH 20Z. KCNY WILL HAVE ON AND
OFF SHOWERS THROUGH 19Z BUT THEN SHOULD GET A SHORT BREAK EARLY
THIS AFTERNOON. THE FOUR CORNERS WILL HAVE -SHRA AND -TSRA
POPPING UP BEGINNING AT ABOUT 18Z AND CONTINUING ON AND OFF
THROUGHOUT THE NEXT 18 HOURS OR SO. MONSOONAL WILL INCREASE
THROUGHOUT THE AFTERNOON SO THE ACTIVE WEATHER WILL BECOME MORE
WIDESPREAD AFTER 22Z FROM WEST TO EAST. RA AND TS WILL OBSCURE
MANY MOUNTAIN LOCATIONS UNTIL 12Z. STORMS WILL BE CAPABLE OF
PRODUCING MVFR/IFR VSBY IN HEAVY RAIN AT MANY TAF LOCATIONS OVER
THE NEXT 24 HOURS.

&&

.HYDROLOGY...
ISSUED AT 345 AM MDT TUE AUG 19 2014

MONSOONAL MOISTURE WILL RETURN TODAY AS AN UPPER LEVEL LOW OVER
CALIFORNIA PULLS DEEP SUBTROPICAL MOISTURE INTO THE REGION.
SHOWERS AND THUNDERSTORMS WILL INCREASE IN COVERAGE FROM WEST TO
EAST THROUGHOUT THE DAY...PEAKING DURING THE LATE AFTERNOON AND
EVENING THEN CONTINUING OVERNIGHT INTO WEDNESDAY MORNING. EXPECT
SOME SMALL STREAM AND ARROYO FLOOD ISSUES BY WEDNESDAY MORNING IN
THE USUAL PROBLEM AREAS. HOWEVER...DO NOT EXPECT SUFFICIENTLY
WIDESPREAD COVERAGE OF TORRENTIAL DOWNPOURS TO WARRANT FLASH FLOOD
WATCH.

&&

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

$$

UPDATE...JAM
SHORT TERM...NL/JOE
LONG TERM...JOE/NL
AVIATION...JAM
HYDROLOGY...NL/JAM




000
FXUS65 KGJT 191659
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1059 AM MDT TUE AUG 19 2014

.UPDATE...
ISSUED AT 1055 AM MDT TUE AUG 19 2014

THE SHIELD OF RAIN SHOWERS IN NORTHWESTERN COLORADO WILL CONTINUE
TO MOVE TO THE NORTHEAST LATE THIS MORNING AND INTO THE EARLY
AFTERNOON. THERE ARE ALREADY SIGNS OF SHOWERS TRAINING IN EAST-
CENTRAL UTAH...AND THOSE RAINFALL RATES ARE LIGHT AT THIS
TIME...ANY RAIN THIS MORNING WILL HELP TO SATURATE THE GROUND FOR
THE HEAVIER RAIN EXPECTED LATER TODAY AND TONIGHT. PRECIPITATION
VALUES RECORDED HAVE GENERALLY BEEN LESS THAN A TENTH OF AN INCH
OVERNIGHT AND THIS MORNING.

FORECAST ON TRACK WITH CLOUD COVER OVER THE CWA KEEPING
STRONG SHOWERS/STORMS SUPPRESSED SO FAR. THERE IS SOME CLEARING
DOWN AT THE FOUR CORNERS WHICH WILL BE SUSCEPTIBLE TO STORMS
DEVELOPING DUE TO DAYTIME HEATING AS WE NEAR THE AFTERNOON.

&&

.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 345 AM MDT TUE AUG 19 2014

PER PREVIOUS DISCUSSION...MONSOONAL SURGE ONGOING EARLY THIS
MORNING WITH DEEP SUBTROPICAL MOISTURE CARRIED NORTHWARD INTO
THE REGION AHEAD OF A LOW PRESSURE SYSTEM OFF THE CENTRAL
CALIFORNIA COAST. A SHORTWAVE EJECTED FROM THE LOW WAS RESPONSIBLE
FOR SHOWERS AND A FEW EMBEDDED THUNDERSTORMS OVER THE SOUTHERN
PORTION OF THE FORECAST AREA EARLY THIS MORNING. CONTINUED MOIST
ADVECTION...DAYTIME WARMING AND THE NORTHWARD TRANSIT OF THE
SHORTWAVE WILL BRING INCREASED SHOWERS AND THUNDERSTORMS FROM LATE
MORNING THROUGH THE AFTERNOON. LATEST BUFR SOUNDINGS INDICATED
PRECIPITABLE WATER VALUES IN EXCESS OF 1 INCH ACROSS SOUTHEAST
UTAH AND EXTREME WEST-CENTRAL AND SOUTHWEST COLORADO THIS
AFTERNOON RAISING THE POTENTIAL FOR HEAVY RAIN. HOWEVER...CONCUR
WITH PREVIOUS FORECAST ASSESSMENT THAT FLASH FLOOD POTENTIAL
MITIGATED BY CLOUD COVER AND FAVORABLE STORM MOTION IN EXCESS OF
15 TO 25 MPH. THAT SAID...LOCALIZED HEAVY RAIN MAY STILL RESULT IN
LOCALIZED FLOODING. AS ALLUDED TO EARLIER...CLOUD COVER WILL KEEP
AFTERNOON HIGHS COOLER AS COMPARED TO YESTERDAY AVERAGING AROUND
10 DEGREES LOWER ON AVERAGE.

AN UNUSUAL SEASONAL CHANGE TO THE SYNOPTIC PATTERN AS THE
SUBTROPICAL RIDGE GETS SHUNTED TO THE GULF COAST AND A PACIFIC
TROUGH DOMINATES. TONIGHT DISORGANIZED ENERGY EJECTS OFF THE
SOUTHERN CALIFORNIA LOW WITH AN ASSOCIATED JET STREAK ORIENTED
SW-NE OVER NE UTAH. SOUTH OF THIS FEATURE MOISTURE IS IMPRESSIVE
ERODING FROM 1.2 INCHES TO AROUND AN INCH TOWARDS WEDNESDAY
MORNING. NOCTURNAL STORMS WILL BE PRODUCING HEAVY RAIN AT TIMES
BUT STORM MOTION WILL BE TO THE ENE AT 20KTS. THIS SPEED WILL
REQUIRE TRAINING OF WET CELLS TO PRODUCE FLOODING ISSUES. STILL
WHERE HEAVY RAIN FALLS TODAY WILL BE THE THREATENED AREAS FOR
POTENTIAL FLOODING TONIGHT. MOISTURE DECREASES TOWARDS THE NE SO
THE PARK/GORE/STEAMBOAT AREA LOOKS LESS LIKELY TO GET HEAVIER
SHOWERS. EVEN THERE THE POTENTIAL IS NOT ZERO. GUSTY STORM WINDS
WILL LIKELY BE WIDESPREAD WITH SMALL HAIL IN THE HOTTEST CELLS.

WEDNESDAY THE CALIFORNIA LOW WORKS OVER SAN DIEGO WITH A
DEFORMATION AXIS STRETCHED INTO NE UTAH AND BEYOND. MOISTURE
ERODES TO AROUND 0.75 INCH WHICH WILL PRODUCE SCATTERED LATE-DAY
CONVECTION. TEMPERATURES REMAIN WELL BELOW NORMAL.

.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 345 AM MDT TUE AUG 19 2014

AT THE SYNOPTIC SCALE THE MODELS ARE STILL NOT IN GOOD AGREEMENT
ON HOW TO HANDLE THE UNUSUAL FOR AUGUST WEST COAST TROUGH. TIMING
OF ITS SLOW PROGRESSION IS IN DOUBT. BUT THROUGH THURSDAY NIGHT WE
REMAIN IN A PERTURBED SW FLOW WITH A WEAK JET STREAK OVER UTAH.
PRECIP WATER VALUES REMAIN NEAR AN INCH IN THE FOUR CORNERS TO
AROUND 0.75 INCH FURTHER NORTH. THIS IS SUFFICIENT FOR SCATTERED
DIURNAL THUNDERSTORMS AND ISOLATED NOCTURNAL STORMS FAVORING THE
SOUTHERN ZONES. THE TROUGH AXIS APPROACHES THE REGION THURSDAY
NIGHT FOR ENHANCED DYNAMICAL SUPPORT AND PERHAPS INCREASED
NIGHTTIME THUNDERSTORMS. GUSTY WINDS AND SMALL HAIL REMAIN A
THREAT WITH STRONGER CELLS.

MODELS CONTINUED TO HANG ONTO LONGWAVE TROUGH OVER THE WEST
THROUGH THE REMAINDER OF THE WEEK. ECMWF DEVELOPS MORE OF A SPLIT
BY FRIDAY ALLOWING SUBTROPICAL MOISTURE TO CONTINUE TO MOVE INTO
THE AREA. THE TROUGH IN THE GFS WAS MORE COHERENT AND THUS FLOW
INDICATED TO BE MORE WESTERLY AND DRIER. REGARDLESS...BOTH
SOLUTIONS CONTAIN ENOUGH MOISTURE FOR DIURNAL SHOWERS AND
THUNDERSTORMS DURING THE LATTER PART OF THE WEEK. UNSETTLED
CONDITIONS LIKELY TO CONTINUE INTO THE WEEKEND. ECMWF NEAR
STAGNANT WITH VERY LITTLE CHANGE RELATIVE TO THAT DESCRIBED
EARLIER. MEANWHILE...GFS REMAINED MORE ZONAL. GIVEN POSITIONING
OF THE TROUGH...COMBINED WITH DAILY SHOWERS AND THUNDERSTORMS
...EXPECT TEMPERATURES WILL REMAIN BELOW NORMAL THURSDAY THROUGH
THE WEEKEND.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1055 AM MDT TUE AUG 19 2014

LIGHT TO MODERATE RAIN SHOWERS OVER NORTHWESTERN COLORADO WILL
CONTINUE TO MOVE NORTHEAST. VCSH IS MOST LIKELY AT
KRIL...KGJT...KASE...AND KEGE THROUGH 20Z. KCNY WILL HAVE ON AND
OFF SHOWERS THROUGH 19Z BUT THEN SHOULD GET A SHORT BREAK EARLY
THIS AFTERNOON. THE FOUR CORNERS WILL HAVE -SHRA AND -TSRA
POPPING UP BEGINNING AT ABOUT 18Z AND CONTINUING ON AND OFF
THROUGHOUT THE NEXT 18 HOURS OR SO. MONSOONAL WILL INCREASE
THROUGHOUT THE AFTERNOON SO THE ACTIVE WEATHER WILL BECOME MORE
WIDESPREAD AFTER 22Z FROM WEST TO EAST. RA AND TS WILL OBSCURE
MANY MOUNTAIN LOCATIONS UNTIL 12Z. STORMS WILL BE CAPABLE OF
PRODUCING MVFR/IFR VSBY IN HEAVY RAIN AT MANY TAF LOCATIONS OVER
THE NEXT 24 HOURS.

&&

.HYDROLOGY...
ISSUED AT 345 AM MDT TUE AUG 19 2014

MONSOONAL MOISTURE WILL RETURN TODAY AS AN UPPER LEVEL LOW OVER
CALIFORNIA PULLS DEEP SUBTROPICAL MOISTURE INTO THE REGION.
SHOWERS AND THUNDERSTORMS WILL INCREASE IN COVERAGE FROM WEST TO
EAST THROUGHOUT THE DAY...PEAKING DURING THE LATE AFTERNOON AND
EVENING THEN CONTINUING OVERNIGHT INTO WEDNESDAY MORNING. EXPECT
SOME SMALL STREAM AND ARROYO FLOOD ISSUES BY WEDNESDAY MORNING IN
THE USUAL PROBLEM AREAS. HOWEVER...DO NOT EXPECT SUFFICIENTLY
WIDESPREAD COVERAGE OF TORRENTIAL DOWNPOURS TO WARRANT FLASH FLOOD
WATCH.

&&

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

$$

UPDATE...JAM
SHORT TERM...NL/JOE
LONG TERM...JOE/NL
AVIATION...JAM
HYDROLOGY...NL/JAM





000
FXUS65 KGJT 190945
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
345 AM MDT TUE AUG 19 2014

.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 345 AM MDT TUE AUG 19 2014

PER PREVIOUS DISCUSSION...MONSOONAL SURGE ONGOING EARLY THIS
MORNING WITH DEEP SUBTROPICAL MOISTURE CARRIED NORTHWARD INTO
THE REGION AHEAD OF A LOW PRESSURE SYSTEM OFF THE CENTRAL
CALIFORNIA COAST. A SHORTWAVE EJECTED FROM THE LOW WAS RESPONSIBLE
FOR SHOWERS AND A FEW EMBEDDED THUNDERSTORMS OVER THE SOUTHERN
PORTION OF THE FORECAST AREA EARLY THIS MORNING. CONTINUED MOIST
ADVECTION...DAYTIME WARMING AND THE NORTHWARD TRANSIT OF THE
SHORTWAVE WILL BRING INCREASED SHOWERS AND THUNDERSTORMS FROM LATE
MORNING THROUGH THE AFTERNOON. LATEST BUFR SOUNDINGS INDICATED
PRECIPITABLE WATER VALUES IN EXCESS OF 1 INCH ACROSS SOUTHEAST
UTAH AND EXTREME WEST-CENTRAL AND SOUTHWEST COLORADO THIS
AFTERNOON RAISING THE POTENTIAL FOR HEAVY RAIN. HOWEVER...CONCUR
WITH PREVIOUS FORECAST ASSESSMENT THAT FLASH FLOOD POTENTIAL
MITIGATED BY CLOUD COVER AND FAVORABLE STORM MOTION IN EXCESS OF
15 TO 25 MPH. THAT SAID...LOCALIZED HEAVY RAIN MAY STILL RESULT IN
LOCALIZED FLOODING. AS ALLUDED TO EARLIER...CLOUD COVER WILL KEEP
AFTERNOON HIGHS COOLER AS COMPARED TO YESTERDAY AVERAGING AROUND
10 DEGREES LOWER ON AVERAGE.

AN UNUSUAL SEASONAL CHANGE TO THE SYNOPTIC PATTERN AS THE
SUBTROPICAL RIDGE GETS SHUNTED TO THE GULF COAST AND A PACIFIC
TROUGH DOMINATES. TONIGHT DISORGANIZED ENERGY EJECTS OFF THE
SOUTHERN CALIFORNIA LOW WITH AN ASSOCIATED JET STREAK ORIENTED
SW-NE OVER NE UTAH. SOUTH OF THIS FEATURE MOISTURE IS IMPRESSIVE
ERODING FROM 1.2 INCHES TO AROUND AN INCH TOWARDS WEDNESDAY
MORNING. NOCTURNAL STORMS WILL BE PRODUCING HEAVY RAIN AT TIMES
BUT STORM MOTION WILL BE TO THE ENE AT 20KTS. THIS SPEED WILL
REQUIRE TRAINING OF WET CELLS TO PRODUCE FLOODING ISSUES. STILL
WHERE HEAVY RAIN FALLS TODAY WILL BE THE THREATENED AREAS FOR
POTENTIAL FLOODING TONIGHT. MOISTURE DECREASES TOWARDS THE NE SO
THE PARK/GORE/STEAMBOAT AREA LOOKS LESS LIKELY TO GET HEAVIER
SHOWERS. EVEN THERE THE POTENTIAL IS NOT ZERO. GUSTY STORM WINDS
WILL LIKELY BE WIDESPREAD WITH SMALL HAIL IN THE HOTTEST CELLS.

WEDNESDAY THE CALIFORNIA LOW WORKS OVER SAN DIEGO WITH A
DEFORMATION AXIS STRETCHED INTO NE UTAH AND BEYOND. MOISTURE
ERODES TO AROUND 0.75 INCH WHICH WILL PRODUCE SCATTERED LATE-DAY
CONVECTION. TEMPERATURES REMAIN WELL BELOW NORMAL.

.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 345 AM MDT TUE AUG 19 2014

AT THE SYNOPTIC SCALE THE MODELS ARE STILL NOT IN GOOD AGREEMENT
ON HOW TO HANDLE THE UNUSUAL FOR AUGUST WEST COAST TROUGH. TIMING
OF ITS SLOW PROGRESSION IS IN DOUBT. BUT THROUGH THURSDAY NIGHT WE
REMAIN IN A PERTURBED SW FLOW WITH A WEAK JET STREAK OVER UTAH.
PRECIP WATER VALUES REMAIN NEAR AN INCH IN THE FOUR CORNERS TO
AROUND 0.75 INCH FURTHER NORTH. THIS IS SUFFICIENT FOR SCATTERED
DIURNAL THUNDERSTORMS AND ISOLATED NOCTURNAL STORMS FAVORING THE
SOUTHERN ZONES. THE TROUGH AXIS APPROACHES THE REGION THURSDAY
NIGHT FOR ENHANCED DYNAMICAL SUPPORT AND PERHAPS INCREASED
NIGHTTIME THUNDERSTORMS. GUSTY WINDS AND SMALL HAIL REMAIN A
THREAT WITH STRONGER CELLS.

MODELS CONTINUED TO HANG ONTO LONGWAVE TROUGH OVER THE WEST
THROUGH THE REMAINDER OF THE WEEK. ECMWF DEVELOPS MORE OF A SPLIT
BY FRIDAY ALLOWING SUBTROPICAL MOISTURE TO CONTINUE TO MOVE INTO
THE AREA. THE TROUGH IN THE GFS WAS MORE COHERENT AND THUS FLOW
INDICATED TO BE MORE WESTERLY AND DRIER. REGARDLESS...BOTH
SOLUTIONS CONTAIN ENOUGH MOISTURE FOR DIURNAL SHOWERS AND
THUNDERSTORMS DURING THE LATTER PART OF THE WEEK. UNSETTLED
CONDITIONS LIKELY TO CONTINUE INTO THE WEEKEND. ECMWF NEAR
STAGNANT WITH VERY LITTLE CHANGE RELATIVE TO THAT DESCRIBED
EARLIER. MEANWHILE...GFS REMAINED MORE ZONAL. GIVEN POSITIONING
OF THE TROUGH...COMBINED WITH DAILY SHOWERS AND THUNDERSTORMS
...EXPECT TEMPERATURES WILL REMAIN BELOW NORMAL THURSDAY THROUGH
THE WEEKEND.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 345 AM MDT TUE AUG 19 2014

A SURGE OF MONSOONAL MOISTURE WILL BRING AN INCREASE IN SHOWER AND
THUNDERSTORM ACTIVITY TODAY. THE DEEPEST MOISTURE WILL IMPACT
EASTERN UTAH AND EXTREME WESTERN COLORADO FIRST WITH STORMS FIRING
AFTER 15Z. THIS ACTIVITY WILL SPREAD EASTWARD AND BECOME MORE
WIDESPREAD AS THE AIRMASS BECOMES WARMER...WETTER...AND MORE
UNSTABLE DURING THE AFTERNOON. MOUNTAINS WILL BE FREQUENTLY
OBSCURED AND TAF SITES WILL HAVE THUNDERSTORMS IN THE VICINITY AND
FACE A GOOD CHANCE OF HAVING STORMS MOVE OVERHEAD. THESE STORMS
WILL BE CAPABLE OF PRODUCING MVFR/IFR VSBY IN HEAVY RAIN. A
DISTURBANCE IMPACTING THE REGION OVERNIGHT WILL KEEP SHOWER AND
THUNDERSTORM ACTIVITY CONTINUING THROUGH 12Z/WED.

&&

.HYDROLOGY...
ISSUED AT 345 AM MDT TUE AUG 19 2014

MONSOONAL MOISTURE WILL RETURN TODAY AS AN UPPER LEVEL LOW OVER
CALIFORNIA PULLS DEEP SUBTROPICAL MOISTURE INTO THE REGION.
SHOWERS AND THUNDERSTORMS WILL INCREASE IN COVERAGE FROM WEST TO
EAST THROUGHOUT THE DAY...PEAKING DURING THE LATE AFTERNOON AND
EVENING THEN CONTINUING OVERNIGHT INTO WEDNESDAY MORNING. EXPECT
SOME SMALL STREAM AND ARROYO FLOOD ISSUES BY WEDNESDAY MORNING IN
THE USUAL PROBLEM AREAS. HOWEVER...DO NOT EXPECT SUFFICIENTLY
WIDESPREAD COVERAGE OF TORRENTIAL DOWNPOURS TO WARRANT FLASH FLOOD
WATCH.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

SHORT TERM...NL/JOE
LONG TERM...JOE/NL
AVIATION...NL
HYDROLOGY...NL/JAM




000
FXUS65 KGJT 190945
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
345 AM MDT TUE AUG 19 2014

.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 345 AM MDT TUE AUG 19 2014

PER PREVIOUS DISCUSSION...MONSOONAL SURGE ONGOING EARLY THIS
MORNING WITH DEEP SUBTROPICAL MOISTURE CARRIED NORTHWARD INTO
THE REGION AHEAD OF A LOW PRESSURE SYSTEM OFF THE CENTRAL
CALIFORNIA COAST. A SHORTWAVE EJECTED FROM THE LOW WAS RESPONSIBLE
FOR SHOWERS AND A FEW EMBEDDED THUNDERSTORMS OVER THE SOUTHERN
PORTION OF THE FORECAST AREA EARLY THIS MORNING. CONTINUED MOIST
ADVECTION...DAYTIME WARMING AND THE NORTHWARD TRANSIT OF THE
SHORTWAVE WILL BRING INCREASED SHOWERS AND THUNDERSTORMS FROM LATE
MORNING THROUGH THE AFTERNOON. LATEST BUFR SOUNDINGS INDICATED
PRECIPITABLE WATER VALUES IN EXCESS OF 1 INCH ACROSS SOUTHEAST
UTAH AND EXTREME WEST-CENTRAL AND SOUTHWEST COLORADO THIS
AFTERNOON RAISING THE POTENTIAL FOR HEAVY RAIN. HOWEVER...CONCUR
WITH PREVIOUS FORECAST ASSESSMENT THAT FLASH FLOOD POTENTIAL
MITIGATED BY CLOUD COVER AND FAVORABLE STORM MOTION IN EXCESS OF
15 TO 25 MPH. THAT SAID...LOCALIZED HEAVY RAIN MAY STILL RESULT IN
LOCALIZED FLOODING. AS ALLUDED TO EARLIER...CLOUD COVER WILL KEEP
AFTERNOON HIGHS COOLER AS COMPARED TO YESTERDAY AVERAGING AROUND
10 DEGREES LOWER ON AVERAGE.

AN UNUSUAL SEASONAL CHANGE TO THE SYNOPTIC PATTERN AS THE
SUBTROPICAL RIDGE GETS SHUNTED TO THE GULF COAST AND A PACIFIC
TROUGH DOMINATES. TONIGHT DISORGANIZED ENERGY EJECTS OFF THE
SOUTHERN CALIFORNIA LOW WITH AN ASSOCIATED JET STREAK ORIENTED
SW-NE OVER NE UTAH. SOUTH OF THIS FEATURE MOISTURE IS IMPRESSIVE
ERODING FROM 1.2 INCHES TO AROUND AN INCH TOWARDS WEDNESDAY
MORNING. NOCTURNAL STORMS WILL BE PRODUCING HEAVY RAIN AT TIMES
BUT STORM MOTION WILL BE TO THE ENE AT 20KTS. THIS SPEED WILL
REQUIRE TRAINING OF WET CELLS TO PRODUCE FLOODING ISSUES. STILL
WHERE HEAVY RAIN FALLS TODAY WILL BE THE THREATENED AREAS FOR
POTENTIAL FLOODING TONIGHT. MOISTURE DECREASES TOWARDS THE NE SO
THE PARK/GORE/STEAMBOAT AREA LOOKS LESS LIKELY TO GET HEAVIER
SHOWERS. EVEN THERE THE POTENTIAL IS NOT ZERO. GUSTY STORM WINDS
WILL LIKELY BE WIDESPREAD WITH SMALL HAIL IN THE HOTTEST CELLS.

WEDNESDAY THE CALIFORNIA LOW WORKS OVER SAN DIEGO WITH A
DEFORMATION AXIS STRETCHED INTO NE UTAH AND BEYOND. MOISTURE
ERODES TO AROUND 0.75 INCH WHICH WILL PRODUCE SCATTERED LATE-DAY
CONVECTION. TEMPERATURES REMAIN WELL BELOW NORMAL.

.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 345 AM MDT TUE AUG 19 2014

AT THE SYNOPTIC SCALE THE MODELS ARE STILL NOT IN GOOD AGREEMENT
ON HOW TO HANDLE THE UNUSUAL FOR AUGUST WEST COAST TROUGH. TIMING
OF ITS SLOW PROGRESSION IS IN DOUBT. BUT THROUGH THURSDAY NIGHT WE
REMAIN IN A PERTURBED SW FLOW WITH A WEAK JET STREAK OVER UTAH.
PRECIP WATER VALUES REMAIN NEAR AN INCH IN THE FOUR CORNERS TO
AROUND 0.75 INCH FURTHER NORTH. THIS IS SUFFICIENT FOR SCATTERED
DIURNAL THUNDERSTORMS AND ISOLATED NOCTURNAL STORMS FAVORING THE
SOUTHERN ZONES. THE TROUGH AXIS APPROACHES THE REGION THURSDAY
NIGHT FOR ENHANCED DYNAMICAL SUPPORT AND PERHAPS INCREASED
NIGHTTIME THUNDERSTORMS. GUSTY WINDS AND SMALL HAIL REMAIN A
THREAT WITH STRONGER CELLS.

MODELS CONTINUED TO HANG ONTO LONGWAVE TROUGH OVER THE WEST
THROUGH THE REMAINDER OF THE WEEK. ECMWF DEVELOPS MORE OF A SPLIT
BY FRIDAY ALLOWING SUBTROPICAL MOISTURE TO CONTINUE TO MOVE INTO
THE AREA. THE TROUGH IN THE GFS WAS MORE COHERENT AND THUS FLOW
INDICATED TO BE MORE WESTERLY AND DRIER. REGARDLESS...BOTH
SOLUTIONS CONTAIN ENOUGH MOISTURE FOR DIURNAL SHOWERS AND
THUNDERSTORMS DURING THE LATTER PART OF THE WEEK. UNSETTLED
CONDITIONS LIKELY TO CONTINUE INTO THE WEEKEND. ECMWF NEAR
STAGNANT WITH VERY LITTLE CHANGE RELATIVE TO THAT DESCRIBED
EARLIER. MEANWHILE...GFS REMAINED MORE ZONAL. GIVEN POSITIONING
OF THE TROUGH...COMBINED WITH DAILY SHOWERS AND THUNDERSTORMS
...EXPECT TEMPERATURES WILL REMAIN BELOW NORMAL THURSDAY THROUGH
THE WEEKEND.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 345 AM MDT TUE AUG 19 2014

A SURGE OF MONSOONAL MOISTURE WILL BRING AN INCREASE IN SHOWER AND
THUNDERSTORM ACTIVITY TODAY. THE DEEPEST MOISTURE WILL IMPACT
EASTERN UTAH AND EXTREME WESTERN COLORADO FIRST WITH STORMS FIRING
AFTER 15Z. THIS ACTIVITY WILL SPREAD EASTWARD AND BECOME MORE
WIDESPREAD AS THE AIRMASS BECOMES WARMER...WETTER...AND MORE
UNSTABLE DURING THE AFTERNOON. MOUNTAINS WILL BE FREQUENTLY
OBSCURED AND TAF SITES WILL HAVE THUNDERSTORMS IN THE VICINITY AND
FACE A GOOD CHANCE OF HAVING STORMS MOVE OVERHEAD. THESE STORMS
WILL BE CAPABLE OF PRODUCING MVFR/IFR VSBY IN HEAVY RAIN. A
DISTURBANCE IMPACTING THE REGION OVERNIGHT WILL KEEP SHOWER AND
THUNDERSTORM ACTIVITY CONTINUING THROUGH 12Z/WED.

&&

.HYDROLOGY...
ISSUED AT 345 AM MDT TUE AUG 19 2014

MONSOONAL MOISTURE WILL RETURN TODAY AS AN UPPER LEVEL LOW OVER
CALIFORNIA PULLS DEEP SUBTROPICAL MOISTURE INTO THE REGION.
SHOWERS AND THUNDERSTORMS WILL INCREASE IN COVERAGE FROM WEST TO
EAST THROUGHOUT THE DAY...PEAKING DURING THE LATE AFTERNOON AND
EVENING THEN CONTINUING OVERNIGHT INTO WEDNESDAY MORNING. EXPECT
SOME SMALL STREAM AND ARROYO FLOOD ISSUES BY WEDNESDAY MORNING IN
THE USUAL PROBLEM AREAS. HOWEVER...DO NOT EXPECT SUFFICIENTLY
WIDESPREAD COVERAGE OF TORRENTIAL DOWNPOURS TO WARRANT FLASH FLOOD
WATCH.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

SHORT TERM...NL/JOE
LONG TERM...JOE/NL
AVIATION...NL
HYDROLOGY...NL/JAM





000
FXUS65 KGJT 190502
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1102 PM MDT MON AUG 18 2014

.SHORT TERM...(TONIGHT THROUGH TUESDAY NIGHT)
ISSUED AT 333 PM MDT MON AUG 18 2014

BIG CHANGES WILL OCCUR OVER THE NEXT 24 HOURS AS AN UNSEASONABLY
STRONG AND NEARLY VERTICALLY STACKED TROUGH...CURRENTLY OVER
CALIFORNIA...MOVES EAST INTO THE GREAT BASIN. THIS BRINGS EASTERN
UTAH AND WESTERN COLORADO INTO IDEAL POSITION FOR DEEP
SUBTROPICAL MOISTURE TO ADVECT INTO THE REGION. PRECIPITABLE
WATER VALUES OF 1 TO 1.3 INCH ARE EXPECTED TO COVER EASTERN UTAH
AND EVEN EXTREME WESTERN COLORADO BY LATE TUESDAY AFTERNOON. THIS
IS ALMOST 2 STANDARD DEVIATIONS ABOVE NORMAL FOR THIS TIME OF
YEAR.

MODELS ARE FORECASTING MULTIPLE VORT MAXES TO REACH THE UT/CO
BORDER THROUGHOUT THE DAY FROM NOON TO MIDNIGHT. THERE IS SOME
UNCERTAINTY ON THE TIMING OF H3 JET SUPPORT OF 60KTS REACHING THE
AREA...WHICH WILL HELP TO PROVIDE ASCENT IN THE UNIMPRESSIVE CAPE
AND SHEAR ENVIRONMENT. EXPECTING CLOUD COVER TO HINDER INSTABILITY
DURING THE DAY...HOWEVER THIS SCENARIO COULD CHANGE IF SUFFICIENT
CLEAR AIR IS ABOUND BY LATE MORNING. THE RAP SHOWS JET SUPPORT
INCHING INTO EASTERN UTAH AND SOUTHWEST COLORADO DURING THE
MORNING ON TUESDAY...HOWEVER THE NAM AND GFS SHOW THE BEST JET
SUPPORT ON TUESDAY NIGHT AND WEDNESDAY MORNING. STORM MOTION WILL
BE DECENT FOR TUESDAY - ABOUT 20 TO 30 KTS...SO COULD NOT JUSTIFY
A FLASH FLOOD WATCH AT THIS TIME. IT WILL RAIN IN MANY LOCATIONS
BY TUESDAY NIGHT...BUT ONLY EXPECTING MODERATE TO HEAVY RAIN
MULTICELLULAR STORMS CAUSING NUISANCE/SMALL STREAM FLOODING AT
THIS TIME. SEE HYDRO SECTION FOR MORE.

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 333 PM MDT MON AUG 18 2014

THE FORECAST AREA REMAINS UNDER SW FLOW WED-THU WITH THE JET AXIS
OVERHEAD. MONSOONAL MOISTURE PLUME WEAKENS WITH PRECIPITABLE WATER
VALUES DROPPING UNDER 1 INCH. NAM/GFS SHOW A WEAK 300 MB JET MAX
ARRIVING ON WED FOR POTENTIAL SUPPORT AND INCREASED VERTICAL
SHEAR....AND SHOULD IT ENTRAIN SOME DRIER MIDLEVEL AIR OVER HIGHER
MOISTURE NEAR THE SURFACE...IT COULD LEAD TO SOME STRONGER STORMS
WED AFTERNOON.

MODELS STILL HAVING TROUBLE HANDLING THE UPPER LOW THAT IS
CURRENTLY DROPPING SOUTH ALONG THE NRN CA COAST...WHICH LOWERS
FORECAST CONFIDENCE AFTER MIDWEEK. BUT AT LEAST THE GFS AND ECWMF
NOW BOTH BRING THE 500 MB LOW INLAND...JUST TIMING AND TRACK ARE
DIFFERENT. THE 12Z GFS SWINGS THE LOW INLAND ACROSS SRN CA WED AND
THEN LIFTS IT NE ACROSS UT AS AN OPEN WAVE ON THU. THIS COULD ADD
SOME DYNAMIC PUNCH TO STORM DEVELOPMENT ON THU. THE 12Z ECMWF IS
SLOWER BRINGING IT INLAND AND TRACKS IT FARTHER SOUTH ACROSS AZ
AND NWRN NM. THE 12Z CANADIAN HAS IT SHEARING OUT ALONG THE SRN CA
COAST THU-FRI. MODELS ALSO SHOW ENERGY DROPPING OUT OF THE GULF OF
AK LATE IN THE WEEK THAT SHOULD MAINTAIN TROUGHING OVER THE PAC
NW/NRN ROCKIES.

FOR NOW...WITH FOLLOW THE CONSENSUS MODEL TREND...WHICH SHOWS A
LESSENING OF STORM COVERAGE THE LAST HALF OF THE WEEK BUT NOT A
COMPLETE CESSATION. LOWER LEVEL MOISTURE LIKELY TO LINGER WITH SOME
SMALLER EMBEDDED WAVES IN THE FLOW THAT COULD TRIGGER ISOLATED-
SCATTERED ACTIVITY ABOUT EACH DAY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1057 PM MDT MON AUG 18 2014

PLENTY OF CONVECTION CONTINUES THIS MORNING WITH SHOWERS AND OCCNL
RUMBLES OF THUNDER. THIS WILL LIKELY CONTINUE THROUGH 09Z WITH A
SLIGHT DOWNTICK AFTER THAT. SHOWERS AND STORMS WILL PICK UP AGAIN
WITH HEAVY RAIN...HAIL...AND GUSTY OUTFLOW WINDS OVERSPREADING THE
AREA FROM NOON ONWARDS WITH WIDEST COVERAGE FROM 21Z ONWARDS.
IFR/MVFR MAY OCCUR OVER AERODROMES DUE TO HEAVIER SHOWERS DROPPING
VIS AND ALSO DROPPING CIGS. MODELS CONTINUE PRECIP OVERNIGHT SO
EXPECT THESE CONDITIONS TO PERSIST THROUGH 06Z TOMORROW. MTN
OBSCURATIONS WILL ALSO BE COMMON.

&&

.HYDROLOGY...
ISSUED AT 333 PM MDT MON AUG 18 2014

MONSOONAL MOISTURE WILL RETURN TOMORROW AS AN UPPER LEVEL LOW OVER
CALIFORNIA PULLS DEEP SUBTROPICAL MOISTURE INTO THE REGION.
SHOWERS AND THUNDERSTORMS WILL INCREASE IN COVERAGE FROM WEST TO
EAST THROUGHOUT THE AFTERNOON AND PEAK DURING THE LATE HOURS OF
THE DAY AND OVERNIGHT INTO WEDNESDAY MORNING. EXPECTING TO HAVE
SMALL STREAM AND ARROYO FLOOD ISSUES BY WEDNESDAY MORNING IN THE
USUAL PROBLEM AREAS...BUT AT THIS NOT EXPECTING HIGH COVERAGE OF
TORRENTIAL DOWNPOURS DUE TO THUNDERSTORMS. THEREFORE...NO WATCHES
HAVE BEEN ISSUED AT THIS TIME.

&&

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

$$

SHORT TERM...JAM
LONG TERM...JAD
AVIATION...TGR
HYDROLOGY...JAM




000
FXUS65 KGJT 190502
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1102 PM MDT MON AUG 18 2014

.SHORT TERM...(TONIGHT THROUGH TUESDAY NIGHT)
ISSUED AT 333 PM MDT MON AUG 18 2014

BIG CHANGES WILL OCCUR OVER THE NEXT 24 HOURS AS AN UNSEASONABLY
STRONG AND NEARLY VERTICALLY STACKED TROUGH...CURRENTLY OVER
CALIFORNIA...MOVES EAST INTO THE GREAT BASIN. THIS BRINGS EASTERN
UTAH AND WESTERN COLORADO INTO IDEAL POSITION FOR DEEP
SUBTROPICAL MOISTURE TO ADVECT INTO THE REGION. PRECIPITABLE
WATER VALUES OF 1 TO 1.3 INCH ARE EXPECTED TO COVER EASTERN UTAH
AND EVEN EXTREME WESTERN COLORADO BY LATE TUESDAY AFTERNOON. THIS
IS ALMOST 2 STANDARD DEVIATIONS ABOVE NORMAL FOR THIS TIME OF
YEAR.

MODELS ARE FORECASTING MULTIPLE VORT MAXES TO REACH THE UT/CO
BORDER THROUGHOUT THE DAY FROM NOON TO MIDNIGHT. THERE IS SOME
UNCERTAINTY ON THE TIMING OF H3 JET SUPPORT OF 60KTS REACHING THE
AREA...WHICH WILL HELP TO PROVIDE ASCENT IN THE UNIMPRESSIVE CAPE
AND SHEAR ENVIRONMENT. EXPECTING CLOUD COVER TO HINDER INSTABILITY
DURING THE DAY...HOWEVER THIS SCENARIO COULD CHANGE IF SUFFICIENT
CLEAR AIR IS ABOUND BY LATE MORNING. THE RAP SHOWS JET SUPPORT
INCHING INTO EASTERN UTAH AND SOUTHWEST COLORADO DURING THE
MORNING ON TUESDAY...HOWEVER THE NAM AND GFS SHOW THE BEST JET
SUPPORT ON TUESDAY NIGHT AND WEDNESDAY MORNING. STORM MOTION WILL
BE DECENT FOR TUESDAY - ABOUT 20 TO 30 KTS...SO COULD NOT JUSTIFY
A FLASH FLOOD WATCH AT THIS TIME. IT WILL RAIN IN MANY LOCATIONS
BY TUESDAY NIGHT...BUT ONLY EXPECTING MODERATE TO HEAVY RAIN
MULTICELLULAR STORMS CAUSING NUISANCE/SMALL STREAM FLOODING AT
THIS TIME. SEE HYDRO SECTION FOR MORE.

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 333 PM MDT MON AUG 18 2014

THE FORECAST AREA REMAINS UNDER SW FLOW WED-THU WITH THE JET AXIS
OVERHEAD. MONSOONAL MOISTURE PLUME WEAKENS WITH PRECIPITABLE WATER
VALUES DROPPING UNDER 1 INCH. NAM/GFS SHOW A WEAK 300 MB JET MAX
ARRIVING ON WED FOR POTENTIAL SUPPORT AND INCREASED VERTICAL
SHEAR....AND SHOULD IT ENTRAIN SOME DRIER MIDLEVEL AIR OVER HIGHER
MOISTURE NEAR THE SURFACE...IT COULD LEAD TO SOME STRONGER STORMS
WED AFTERNOON.

MODELS STILL HAVING TROUBLE HANDLING THE UPPER LOW THAT IS
CURRENTLY DROPPING SOUTH ALONG THE NRN CA COAST...WHICH LOWERS
FORECAST CONFIDENCE AFTER MIDWEEK. BUT AT LEAST THE GFS AND ECWMF
NOW BOTH BRING THE 500 MB LOW INLAND...JUST TIMING AND TRACK ARE
DIFFERENT. THE 12Z GFS SWINGS THE LOW INLAND ACROSS SRN CA WED AND
THEN LIFTS IT NE ACROSS UT AS AN OPEN WAVE ON THU. THIS COULD ADD
SOME DYNAMIC PUNCH TO STORM DEVELOPMENT ON THU. THE 12Z ECMWF IS
SLOWER BRINGING IT INLAND AND TRACKS IT FARTHER SOUTH ACROSS AZ
AND NWRN NM. THE 12Z CANADIAN HAS IT SHEARING OUT ALONG THE SRN CA
COAST THU-FRI. MODELS ALSO SHOW ENERGY DROPPING OUT OF THE GULF OF
AK LATE IN THE WEEK THAT SHOULD MAINTAIN TROUGHING OVER THE PAC
NW/NRN ROCKIES.

FOR NOW...WITH FOLLOW THE CONSENSUS MODEL TREND...WHICH SHOWS A
LESSENING OF STORM COVERAGE THE LAST HALF OF THE WEEK BUT NOT A
COMPLETE CESSATION. LOWER LEVEL MOISTURE LIKELY TO LINGER WITH SOME
SMALLER EMBEDDED WAVES IN THE FLOW THAT COULD TRIGGER ISOLATED-
SCATTERED ACTIVITY ABOUT EACH DAY.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1057 PM MDT MON AUG 18 2014

PLENTY OF CONVECTION CONTINUES THIS MORNING WITH SHOWERS AND OCCNL
RUMBLES OF THUNDER. THIS WILL LIKELY CONTINUE THROUGH 09Z WITH A
SLIGHT DOWNTICK AFTER THAT. SHOWERS AND STORMS WILL PICK UP AGAIN
WITH HEAVY RAIN...HAIL...AND GUSTY OUTFLOW WINDS OVERSPREADING THE
AREA FROM NOON ONWARDS WITH WIDEST COVERAGE FROM 21Z ONWARDS.
IFR/MVFR MAY OCCUR OVER AERODROMES DUE TO HEAVIER SHOWERS DROPPING
VIS AND ALSO DROPPING CIGS. MODELS CONTINUE PRECIP OVERNIGHT SO
EXPECT THESE CONDITIONS TO PERSIST THROUGH 06Z TOMORROW. MTN
OBSCURATIONS WILL ALSO BE COMMON.

&&

.HYDROLOGY...
ISSUED AT 333 PM MDT MON AUG 18 2014

MONSOONAL MOISTURE WILL RETURN TOMORROW AS AN UPPER LEVEL LOW OVER
CALIFORNIA PULLS DEEP SUBTROPICAL MOISTURE INTO THE REGION.
SHOWERS AND THUNDERSTORMS WILL INCREASE IN COVERAGE FROM WEST TO
EAST THROUGHOUT THE AFTERNOON AND PEAK DURING THE LATE HOURS OF
THE DAY AND OVERNIGHT INTO WEDNESDAY MORNING. EXPECTING TO HAVE
SMALL STREAM AND ARROYO FLOOD ISSUES BY WEDNESDAY MORNING IN THE
USUAL PROBLEM AREAS...BUT AT THIS NOT EXPECTING HIGH COVERAGE OF
TORRENTIAL DOWNPOURS DUE TO THUNDERSTORMS. THEREFORE...NO WATCHES
HAVE BEEN ISSUED AT THIS TIME.

&&

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

$$

SHORT TERM...JAM
LONG TERM...JAD
AVIATION...TGR
HYDROLOGY...JAM





000
FXUS65 KGJT 182323
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
523 PM MDT MON AUG 18 2014

.SHORT TERM...(TONIGHT THROUGH TUESDAY NIGHT)
ISSUED AT 333 PM MDT MON AUG 18 2014

BIG CHANGES WILL OCCUR OVER THE NEXT 24 HOURS AS AN UNSEASONABLY
STRONG AND NEARLY VERTICALLY STACKED TROUGH...CURRENTLY OVER
CALIFORNIA...MOVES EAST INTO THE GREAT BASIN. THIS BRINGS EASTERN
UTAH AND WESTERN COLORADO INTO IDEAL POSITION FOR DEEP
SUBTROPICAL MOISTURE TO ADVECT INTO THE REGION. PRECIPITABLE
WATER VALUES OF 1 TO 1.3 INCH ARE EXPECTED TO COVER EASTERN UTAH
AND EVEN EXTREME WESTERN COLORADO BY LATE TUESDAY AFTERNOON. THIS
IS ALMOST 2 STANDARD DEVIATIONS ABOVE NORMAL FOR THIS TIME OF
YEAR.

MODELS ARE FORECASTING MULTIPLE VORT MAXES TO REACH THE UT/CO
BORDER THROUGHOUT THE DAY FROM NOON TO MIDNIGHT. THERE IS SOME
UNCERTAINTY ON THE TIMING OF H3 JET SUPPORT OF 60KTS REACHING THE
AREA...WHICH WILL HELP TO PROVIDE ASCENT IN THE UNIMPRESSIVE CAPE
AND SHEAR ENVIRONMENT. EXPECTING CLOUD COVER TO HINDER INSTABILITY
DURING THE DAY...HOWEVER THIS SCENARIO COULD CHANGE IF SUFFICIENT
CLEAR AIR IS ABOUND BY LATE MORNING. THE RAP SHOWS JET SUPPORT
INCHING INTO EASTERN UTAH AND SOUTHWEST COLORADO DURING THE
MORNING ON TUESDAY...HOWEVER THE NAM AND GFS SHOW THE BEST JET
SUPPORT ON TUESDAY NIGHT AND WEDNESDAY MORNING. STORM MOTION WILL
BE DECENT FOR TUESDAY - ABOUT 20 TO 30 KTS...SO COULD NOT JUSTIFY
A FLASH FLOOD WATCH AT THIS TIME. IT WILL RAIN IN MANY LOCATIONS
BY TUESDAY NIGHT...BUT ONLY EXPECTING MODERATE TO HEAVY RAIN
MULTICELLULAR STORMS CAUSING NUISANCE/SMALL STREAM FLOODING AT
THIS TIME. SEE HYDRO SECTION FOR MORE.

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 333 PM MDT MON AUG 18 2014

THE FORECAST AREA REMAINS UNDER SW FLOW WED-THU WITH THE JET AXIS
OVERHEAD. MONSOONAL MOISTURE PLUME WEAKENS WITH PRECIPITABLE WATER
VALUES DROPPING UNDER 1 INCH. NAM/GFS SHOW A WEAK 300 MB JET MAX
ARRIVING ON WED FOR POTENTIAL SUPPORT AND INCREASED VERTICAL
SHEAR....AND SHOULD IT ENTRAIN SOME DRIER MIDLEVEL AIR OVER HIGHER
MOISTURE NEAR THE SURFACE...IT COULD LEAD TO SOME STRONGER STORMS
WED AFTERNOON.

MODELS STILL HAVING TROUBLE HANDLING THE UPPER LOW THAT IS
CURRENTLY DROPPING SOUTH ALONG THE NRN CA COAST...WHICH LOWERS
FORECAST CONFIDENCE AFTER MIDWEEK. BUT AT LEAST THE GFS AND ECWMF
NOW BOTH BRING THE 500 MB LOW INLAND...JUST TIMING AND TRACK ARE
DIFFERENT. THE 12Z GFS SWINGS THE LOW INLAND ACROSS SRN CA WED AND
THEN LIFTS IT NE ACROSS UT AS AN OPEN WAVE ON THU. THIS COULD ADD
SOME DYNAMIC PUNCH TO STORM DEVELOPMENT ON THU. THE 12Z ECMWF IS
SLOWER BRINGING IT INLAND AND TRACKS IT FARTHER SOUTH ACROSS AZ
AND NWRN NM. THE 12Z CANADIAN HAS IT SHEARING OUT ALONG THE SRN CA
COAST THU-FRI. MODELS ALSO SHOW ENERGY DROPPING OUT OF THE GULF OF
AK LATE IN THE WEEK THAT SHOULD MAINTAIN TROUGHING OVER THE PAC
NW/NRN ROCKIES.

FOR NOW...WITH FOLLOW THE CONSENSUS MODEL TREND...WHICH SHOWS A
LESSENING OF STORM COVERAGE THE LAST HALF OF THE WEEK BUT NOT A
COMPLETE CESSATION. LOWER LEVEL MOISTURE LIKELY TO LINGER WITH SOME
SMALLER EMBEDDED WAVES IN THE FLOW THAT COULD TRIGGER ISOLATED-
SCATTERED ACTIVITY ABOUT EACH DAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 519 PM MDT MON AUG 18 2014

MOST CONVECTION IS EXPECTED TO DIE DOWN OVERNIGHT THOUGH SOME
LINGERING SHOWERS...MAYBE A QUICK RUMBLE OF THUNDER...IS POSSIBLE
THROUGH 09Z. FLYING CONDITIONS WILL DETERIORATE TOMORROW AS A
DISTURBANCE MOVES OVERHEAD WITH MID LEVEL BKN TO OCCNL OVC CIGS
EXPECTED FROM 18Z ONWARDS. MANY AREAS WILL SEE VCSH BECOMING VCTS
AS THE AFTERNOON PROGRESSES. THE STRONGER CELLS WILL PRODUCE MVFR
TO POSSIBLY IFR VIS AT TIMES DUE TO LOWERED VISIBILITIES. GUSTY
OUTFLOW WINDS ARE ALSO POSSIBLE REACHING 40+ MPH IN THE AFTERNOON
AND EVENING HOURS. MTN TOPS WILL LIKELY BE OBSCURED FOR MOST OF
THE FORECAST AREA. CONVECTION IS EXPECTED TO CONTINUE OVERNIGHT
THOUGH COVERAGE WILL LESS THAN SEEN DURING THE DAY.

&&

.HYDROLOGY...
ISSUED AT 333 PM MDT MON AUG 18 2014

MONSOONAL MOISTURE WILL RETURN TOMORROW AS AN UPPER LEVEL LOW OVER
CALIFORNIA PULLS DEEP SUBTROPICAL MOISTURE INTO THE REGION.
SHOWERS AND THUNDERSTORMS WILL INCREASE IN COVERAGE FROM WEST TO
EAST THROUGHOUT THE AFTERNOON AND PEAK DURING THE LATE HOURS OF
THE DAY AND OVERNIGHT INTO WEDNESDAY MORNING. EXPECTING TO HAVE
SMALL STREAM AND ARROYO FLOOD ISSUES BY WEDNESDAY MORNING IN THE
USUAL PROBLEM AREAS...BUT AT THIS NOT EXPECTING HIGH COVERAGE OF
TORRENTIAL DOWNPOURS DUE TO THUNDERSTORMS. THEREFORE...NO WATCHES
HAVE BEEN ISSUED AT THIS TIME.

&&

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

$$

SHORT TERM...JAM
LONG TERM...JAD
AVIATION...TGR
HYDROLOGY...JAM





000
FXUS65 KGJT 182323
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
523 PM MDT MON AUG 18 2014

.SHORT TERM...(TONIGHT THROUGH TUESDAY NIGHT)
ISSUED AT 333 PM MDT MON AUG 18 2014

BIG CHANGES WILL OCCUR OVER THE NEXT 24 HOURS AS AN UNSEASONABLY
STRONG AND NEARLY VERTICALLY STACKED TROUGH...CURRENTLY OVER
CALIFORNIA...MOVES EAST INTO THE GREAT BASIN. THIS BRINGS EASTERN
UTAH AND WESTERN COLORADO INTO IDEAL POSITION FOR DEEP
SUBTROPICAL MOISTURE TO ADVECT INTO THE REGION. PRECIPITABLE
WATER VALUES OF 1 TO 1.3 INCH ARE EXPECTED TO COVER EASTERN UTAH
AND EVEN EXTREME WESTERN COLORADO BY LATE TUESDAY AFTERNOON. THIS
IS ALMOST 2 STANDARD DEVIATIONS ABOVE NORMAL FOR THIS TIME OF
YEAR.

MODELS ARE FORECASTING MULTIPLE VORT MAXES TO REACH THE UT/CO
BORDER THROUGHOUT THE DAY FROM NOON TO MIDNIGHT. THERE IS SOME
UNCERTAINTY ON THE TIMING OF H3 JET SUPPORT OF 60KTS REACHING THE
AREA...WHICH WILL HELP TO PROVIDE ASCENT IN THE UNIMPRESSIVE CAPE
AND SHEAR ENVIRONMENT. EXPECTING CLOUD COVER TO HINDER INSTABILITY
DURING THE DAY...HOWEVER THIS SCENARIO COULD CHANGE IF SUFFICIENT
CLEAR AIR IS ABOUND BY LATE MORNING. THE RAP SHOWS JET SUPPORT
INCHING INTO EASTERN UTAH AND SOUTHWEST COLORADO DURING THE
MORNING ON TUESDAY...HOWEVER THE NAM AND GFS SHOW THE BEST JET
SUPPORT ON TUESDAY NIGHT AND WEDNESDAY MORNING. STORM MOTION WILL
BE DECENT FOR TUESDAY - ABOUT 20 TO 30 KTS...SO COULD NOT JUSTIFY
A FLASH FLOOD WATCH AT THIS TIME. IT WILL RAIN IN MANY LOCATIONS
BY TUESDAY NIGHT...BUT ONLY EXPECTING MODERATE TO HEAVY RAIN
MULTICELLULAR STORMS CAUSING NUISANCE/SMALL STREAM FLOODING AT
THIS TIME. SEE HYDRO SECTION FOR MORE.

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 333 PM MDT MON AUG 18 2014

THE FORECAST AREA REMAINS UNDER SW FLOW WED-THU WITH THE JET AXIS
OVERHEAD. MONSOONAL MOISTURE PLUME WEAKENS WITH PRECIPITABLE WATER
VALUES DROPPING UNDER 1 INCH. NAM/GFS SHOW A WEAK 300 MB JET MAX
ARRIVING ON WED FOR POTENTIAL SUPPORT AND INCREASED VERTICAL
SHEAR....AND SHOULD IT ENTRAIN SOME DRIER MIDLEVEL AIR OVER HIGHER
MOISTURE NEAR THE SURFACE...IT COULD LEAD TO SOME STRONGER STORMS
WED AFTERNOON.

MODELS STILL HAVING TROUBLE HANDLING THE UPPER LOW THAT IS
CURRENTLY DROPPING SOUTH ALONG THE NRN CA COAST...WHICH LOWERS
FORECAST CONFIDENCE AFTER MIDWEEK. BUT AT LEAST THE GFS AND ECWMF
NOW BOTH BRING THE 500 MB LOW INLAND...JUST TIMING AND TRACK ARE
DIFFERENT. THE 12Z GFS SWINGS THE LOW INLAND ACROSS SRN CA WED AND
THEN LIFTS IT NE ACROSS UT AS AN OPEN WAVE ON THU. THIS COULD ADD
SOME DYNAMIC PUNCH TO STORM DEVELOPMENT ON THU. THE 12Z ECMWF IS
SLOWER BRINGING IT INLAND AND TRACKS IT FARTHER SOUTH ACROSS AZ
AND NWRN NM. THE 12Z CANADIAN HAS IT SHEARING OUT ALONG THE SRN CA
COAST THU-FRI. MODELS ALSO SHOW ENERGY DROPPING OUT OF THE GULF OF
AK LATE IN THE WEEK THAT SHOULD MAINTAIN TROUGHING OVER THE PAC
NW/NRN ROCKIES.

FOR NOW...WITH FOLLOW THE CONSENSUS MODEL TREND...WHICH SHOWS A
LESSENING OF STORM COVERAGE THE LAST HALF OF THE WEEK BUT NOT A
COMPLETE CESSATION. LOWER LEVEL MOISTURE LIKELY TO LINGER WITH SOME
SMALLER EMBEDDED WAVES IN THE FLOW THAT COULD TRIGGER ISOLATED-
SCATTERED ACTIVITY ABOUT EACH DAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 519 PM MDT MON AUG 18 2014

MOST CONVECTION IS EXPECTED TO DIE DOWN OVERNIGHT THOUGH SOME
LINGERING SHOWERS...MAYBE A QUICK RUMBLE OF THUNDER...IS POSSIBLE
THROUGH 09Z. FLYING CONDITIONS WILL DETERIORATE TOMORROW AS A
DISTURBANCE MOVES OVERHEAD WITH MID LEVEL BKN TO OCCNL OVC CIGS
EXPECTED FROM 18Z ONWARDS. MANY AREAS WILL SEE VCSH BECOMING VCTS
AS THE AFTERNOON PROGRESSES. THE STRONGER CELLS WILL PRODUCE MVFR
TO POSSIBLY IFR VIS AT TIMES DUE TO LOWERED VISIBILITIES. GUSTY
OUTFLOW WINDS ARE ALSO POSSIBLE REACHING 40+ MPH IN THE AFTERNOON
AND EVENING HOURS. MTN TOPS WILL LIKELY BE OBSCURED FOR MOST OF
THE FORECAST AREA. CONVECTION IS EXPECTED TO CONTINUE OVERNIGHT
THOUGH COVERAGE WILL LESS THAN SEEN DURING THE DAY.

&&

.HYDROLOGY...
ISSUED AT 333 PM MDT MON AUG 18 2014

MONSOONAL MOISTURE WILL RETURN TOMORROW AS AN UPPER LEVEL LOW OVER
CALIFORNIA PULLS DEEP SUBTROPICAL MOISTURE INTO THE REGION.
SHOWERS AND THUNDERSTORMS WILL INCREASE IN COVERAGE FROM WEST TO
EAST THROUGHOUT THE AFTERNOON AND PEAK DURING THE LATE HOURS OF
THE DAY AND OVERNIGHT INTO WEDNESDAY MORNING. EXPECTING TO HAVE
SMALL STREAM AND ARROYO FLOOD ISSUES BY WEDNESDAY MORNING IN THE
USUAL PROBLEM AREAS...BUT AT THIS NOT EXPECTING HIGH COVERAGE OF
TORRENTIAL DOWNPOURS DUE TO THUNDERSTORMS. THEREFORE...NO WATCHES
HAVE BEEN ISSUED AT THIS TIME.

&&

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

$$

SHORT TERM...JAM
LONG TERM...JAD
AVIATION...TGR
HYDROLOGY...JAM




000
FXUS65 KGJT 182135
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
335 PM MDT MON AUG 18 2014

.SHORT TERM...(TONIGHT THROUGH TUESDAY NIGHT)
ISSUED AT 333 PM MDT MON AUG 18 2014

BIG CHANGES WILL OCCUR OVER THE NEXT 24 HOURS AS AN UNSEASONABLY
STRONG AND NEARLY VERTICALLY STACKED TROUGH...CURRENTLY OVER
CALIFORNIA...MOVES EAST INTO THE GREAT BASIN. THIS BRINGS EASTERN
UTAH AND WESTERN COLORADO INTO IDEAL POSITION FOR DEEP
SUBTROPICAL MOISTURE TO ADVECT INTO THE REGION. PRECIPITABLE
WATER VALUES OF 1 TO 1.3 INCH ARE EXPECTED TO COVER EASTERN UTAH
AND EVEN EXTREME WESTERN COLORADO BY LATE TUESDAY AFTERNOON. THIS
IS ALMOST 2 STANDARD DEVIATIONS ABOVE NORMAL FOR THIS TIME OF
YEAR.

MODELS ARE FORECASTING MULTIPLE VORT MAXES TO REACH THE UT/CO
BORDER THROUGHOUT THE DAY FROM NOON TO MIDNIGHT. THERE IS SOME
UNCERTAINTY ON THE TIMING OF H3 JET SUPPORT OF 60KTS REACHING THE
AREA...WHICH WILL HELP TO PROVIDE ASCENT IN THE UNIMPRESSIVE CAPE
AND SHEAR ENVIRONMENT. EXPECTING CLOUD COVER TO HINDER INSTABILITY
DURING THE DAY...HOWEVER THIS SCENARIO COULD CHANGE IF SUFFICIENT
CLEAR AIR IS ABOUND BY LATE MORNING. THE RAP SHOWS JET SUPPORT
INCHING INTO EASTERN UTAH AND SOUTHWEST COLORADO DURING THE
MORNING ON TUESDAY...HOWEVER THE NAM AND GFS SHOW THE BEST JET
SUPPORT ON TUESDAY NIGHT AND WEDNESDAY MORNING. STORM MOTION WILL
BE DECENT FOR TUESDAY - ABOUT 20 TO 30 KTS...SO COULD NOT JUSTIFY
A FLASH FLOOD WATCH AT THIS TIME. IT WILL RAIN IN MANY LOCATIONS
BY TUESDAY NIGHT...BUT ONLY EXPECTING MODERATE TO HEAVY RAIN
MULTICELLULAR STORMS CAUSING NUISANCE/SMALL STREAM FLOODING AT
THIS TIME. SEE HYDRO SECTION FOR MORE.

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 333 PM MDT MON AUG 18 2014

THE FORECAST AREA REMAINS UNDER SW FLOW WED-THU WITH THE JET AXIS
OVERHEAD. MONSOONAL MOISTURE PLUME WEAKENS WITH PRECIPITABLE WATER
VALUES DROPPING UNDER 1 INCH. NAM/GFS SHOW A WEAK 300 MB JET MAX
ARRIVING ON WED FOR POTENTIAL SUPPORT AND INCREASED VERTICAL
SHEAR....AND SHOULD IT ENTRAIN SOME DRIER MIDLEVEL AIR OVER HIGHER
MOISTURE NEAR THE SURFACE...IT COULD LEAD TO SOME STRONGER STORMS
WED AFTERNOON.

MODELS STILL HAVING TROUBLE HANDLING THE UPPER LOW THAT IS
CURRENTLY DROPPING SOUTH ALONG THE NRN CA COAST...WHICH LOWERS
FORECAST CONFIDENCE AFTER MIDWEEK. BUT AT LEAST THE GFS AND ECWMF
NOW BOTH BRING THE 500 MB LOW INLAND...JUST TIMING AND TRACK ARE
DIFFERENT. THE 12Z GFS SWINGS THE LOW INLAND ACROSS SRN CA WED AND
THEN LIFTS IT NE ACROSS UT AS AN OPEN WAVE ON THU. THIS COULD ADD
SOME DYNAMIC PUNCH TO STORM DEVELOPMENT ON THU. THE 12Z ECMWF IS
SLOWER BRINGING IT INLAND AND TRACKS IT FARTHER SOUTH ACROSS AZ
AND NWRN NM. THE 12Z CANADIAN HAS IT SHEARING OUT ALONG THE SRN CA
COAST THU-FRI. MODELS ALSO SHOW ENERGY DROPPING OUT OF THE GULF OF
AK LATE IN THE WEEK THAT SHOULD MAINTAIN TROUGHING OVER THE PAC
NW/NRN ROCKIES.

FOR NOW...WITH FOLLOW THE CONSENSUS MODEL TREND...WHICH SHOWS A
LESSENING OF STORM COVERAGE THE LAST HALF OF THE WEEK BUT NOT A
COMPLETE CESSATION. LOWER LEVEL MOISTURE LIKELY TO LINGER WITH SOME
SMALLER EMBEDDED WAVES IN THE FLOW THAT COULD TRIGGER ISOLATED-
SCATTERED ACTIVITY ABOUT EACH DAY.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1108 AM MDT MON AUG 18 2014

A LINE OF -SHRA SOUTH OF KCAG BUT NORTH OF THE BOOKCLIFFS
CONTINUES TO MOVE EAST THROUGH THE AREA THANKS TO A WEAK WEATHER
DISTURBANCE ACROSS NORTHERN COLORADO. ISOLATED -RA/-TSRA WILL
INCREASE IN COVERAGE OVER THE MOUNTAINS AROUND 18Z. KEGE AND KASE
HAVE A SLIGHT CHANCE OF RECEIVING A SHOWER OR THUNDERSTORM TODAY.
MOISTURE WILL INCREASE AFTER 12Z TUESDAY MORNING FROM THE
SOUTHWEST AND INCREASE THE COVERAGE OF RAIN SHOWERS AND
THUNDERSTORMS BY 18Z TUESDAY.


&&

.HYDROLOGY...
ISSUED AT 333 PM MDT MON AUG 18 2014

MONSOONAL MOISTURE WILL RETURN TOMORROW AS AN UPPER LEVEL LOW OVER
CALIFORNIA PULLS DEEP SUBTROPICAL MOISTURE INTO THE REGION.
SHOWERS AND THUNDERSTORMS WILL INCREASE IN COVERAGE FROM WEST TO
EAST THOUGHOUT THE AFTERNOON AND PEAK DURING THE LATE HOURS OF THE
DAY AND OVERNIGHT INTO WEDNESDAY MORNING. EXPECTING TO HAVE SMALL
STREAM AND ARROYO FLOOD ISSUES BY WEDNESDAY MORNING IN THE USUAL
PROBLEM AREAS...BUT AT THIS NOT EXPECTING HIGH COVERAGE OF
TORRENTIAL DOWNPOURS DUE TO THUNDERSTORMS. THEREFORE...NO WATCHES
HAVE BEEN ISSUED AT THIS TIME.

&&

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

$$

SHORT TERM...JAM
LONG TERM...JAD
AVIATION...JAM
HYDROLOGY...JAM




000
FXUS65 KGJT 181708
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1108 AM MDT MON AUG 18 2014

.UPDATE...
ISSUED AT 1108 AM MDT MON AUG 18 2014

A JET STREAK OVER NORTHERN COLORADO CONTINUES TO SUSTAIN SHOWERS
OVER THE UINTA BASIN OF EASTERN UTAH AND FROM ABOUT RANGELY TO
VAIL PASS IN NORTHERN COLORADO. LITTLE PRECIPITATION IS EXPECTED
WITH THESE SHOWERS. ANTICIPATING A FEW SHOWERS DEVELOPING OVER
SOUTHEASTERN UTAH WITHIN THE NEXT FEW HOURS AHEAD OF THE DEEPER
PLUME OF MOISTURE WHICH WILL REACH THE FOUR CORNERS TONIGHT.

&&

.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 241 AM MDT MON AUG 18 2014

TODAY...STARTING OUT OVERNIGHT INTO THE EARLY MORNING WITH A FEW
SHOWERS AND THUNDERSTORMS MAINLY THE NORTHERN PORTION OF THE NW
SAN JUAN MOUNTAINS AND ALSO IN AREAS OF NW CO AND NE UT. THEN
DAYTIME HEATING WILL RESULT IN SCATTERED SHOWERS AND THUNDERSTORMS
THIS AFTERNOON MAINLY MOUNTAINS. WITH PWATS DOWN TO LESS THAN 0.75
INCH TODAY...ONLY EXPECT BRIEF MODERATE RAINFALL FROM STORMS...
THOUGH GUSTY OUTFLOW WINDS COULD BE IN EXCESS OF 45 MPH FROM SOME
STORMS. EXPECT MAX TEMPERATURES ABOUT THE SAME OR SLIGHTLY LOWER
THAN YESTERDAY.

THEN CONFIDENCE IS HIGH FOR THE NEXT MONSOONAL SURGE TONIGHT
THROUGH TUESDAY ESPECIALLY IN EASTERN UTAH AND FAR WESTERN
COLORADO. SEVERAL FACTORS SUPPORT THIS. FIRST AN UNSEASONABLY
VIGOROUS UPPER LOW WORKS DOWN THE CALIFORNIA COAST PUSHING THE
SUBTROPICAL HIGH CENTER OUT INTO TEXAS. 0-6KM SW FLOW ADVECTS DEEP
MOISTURE FROM THE BAJA REGION. SE UTAH PRECIP WATER VALUES CLIMB
OVER AN INCH THIS EVENING REACHING NEAR 1.2 INCHES BY NOON
TUESDAY. A SIGNIFICANT CHUNK OF JET-SUPPORTED ENERGY LIFTS THROUGH
EASTERN UTAH ON TUESDAY WITH THE BEST FORCING IN THE RIGHT
ENTRANCE QUAD OF THE 70KT JET OVER NE UTAH. THE BEST MIXTURE OF
FORCING AND DEEP MOISTURE LOOKS TO BE IN SE-EASTCENTRAL UTAH AND
FAR WESTERN COLORADO. INSTABILITY LOOKS LIMITED DUE TO LESS
SURFACE HEATING. STILL THE STRONGEST CELLS WILL PRODUCE SMALL
HAIL. STORM MOTION WILL BE TO THE NNE AT 20-25KTS SO OUTFLOW WIND
GUSTS OF 30-40 MPH SHOULD BE COMMON IN THE WESTERN CWA. THE
EASTERN CWA IS EXPECTED TO HAVE A LOWER THREAT OF HEAVY RAINS THAN
THE WESTERN PORTION.

.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 241 AM MDT MON AUG 18 2014

TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...
FORCING LIFTS NE OF THIS FORECAST AREA TUESDAY EVENING BUT DEEP
MOISTURE AND BOUNDARY INTERACTION SHOULD KEEP STORMS FIRING BEYOND
MIDNIGHT. WEDNESDAY THE WEST COAST TROUGH SETTLES NEAR SAN DIEGO.
SLIGHTLY DRIER AIR WORKS OVER UTAH. NO ORGANIZED DISTURBANCES SEEN
EJECTING OFF THE SOUTHERN CALIFORNIA LOW BUT MINOR WAVES WILL
LIKELY PROVIDE ADDITIONAL LIFT. STORM MOTION WILL BE TO THE ENE AT
20KTS AGAIN THREATENING GUSTY OUTFLOW WINDS. HEAVY RAIN POTENTIAL
DECREASES SOMEWHAT ON WEDNESDAY. THE MODELS END SHOWERS WEDNESDAY
EVENING. BUT PRECIP WATER VALUES REMAIN OVER 0.75 INCH OVER THE
SOUTHERN 2/3 OF THE CWA SO ISOLATED NOCTURNAL STORMS ARE
ANTICIPATED TO PERSIST THERE.

THURSDAY AND FRIDAY...
MODELS START OUT EARLY THURSDAY WITH CLOSED LOW CENTERED NEAR
SOUTHERN CA COAST...THEN THEY DIVERGE THEREAFTER. THE GFS MOVES
THE UPPER LOW INLAND THURSDAY AND INTO OUR CWA ON FRIDAY AS IT
COMES INTO PHASE WITH THE TROUGH TO THE NORTH. EC AND CANADIAN
MODELS WAIT TO MOVE THE UPPER LOW INLAND UNTIL FRIDAY AND SLOWLY
BRING IT UP TO THE FOUR CORNERS AREA BY SUNDAY. THE GFS SOLUTION
HAS ANOTHER SURGE OF MONSOONAL MOISTURE FOR OUR CWA ON THURSDAY
AND FRIDAY...WITH DRIER WESTERLY FLOW OVER THE WEEKEND. IN
CONTRAST...EC IS DRIER ON THURSDAY AND FRIDAY WITH THE MONSOONAL
MOISTURE FOR OUR CWA FRIDAY NIGHT INTO SUNDAY. NO SINGLE MODEL
SOLUTION PREFERRED AT THIS TIME...AND BELIEVE THE BROAD BRUSH
TREATMENT WITH SCATTERED SHOWERS AND THUNDERSTORMS IS THE BEST
FORECAST DURING THIS TIME PERIOD. MAX TEMPERATURES SHOULD
GENERALLY BE A LITTLE LOWER THAN NORMAL THROUGH THIS PERIOD DUE TO
CLOUDS AND SHOWERS...WHILE MIN TEMPERATURES LIKELY TO BE NEAR OR
A LITTLE ABOVE NORMAL DUE TO CLOUD COVER AND ELEVATED DEW POINT
TEMPERATURES.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1108 AM MDT MON AUG 18 2014

A LINE OF -SHRA SOUTH OF KCAG BUT NORTH OF THE BOOKCLIFFS
CONTINUES TO MOVE EAST THROUGH THE AREA THANKS TO A WEAK WEATHER
DISTURBANCE ACROSS NORTHERN COLORADO. ISOLATED -RA/-TSRA WILL
INCREASE IN COVERAGE OVER THE MOUNTAINS AROUND 18Z. KEGE AND KASE
HAVE A SLIGHT CHANCE OF RECEIVING A SHOWER OR THUNDERSTORM TODAY.
MOISTURE WILL INCREASE AFTER 12Z TUESDAY MORNING FROM THE
SOUTHWEST AND INCREASE THE COVERAGE OF RAIN SHOWERS AND
THUNDERSTORMS BY 18Z TUESDAY.

&&

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

$$

UPDATE...JAM
SHORT TERM...JRP/JOE
LONG TERM...JOE/JRP
AVIATION...JAM




000
FXUS65 KGJT 181708
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1108 AM MDT MON AUG 18 2014

.UPDATE...
ISSUED AT 1108 AM MDT MON AUG 18 2014

A JET STREAK OVER NORTHERN COLORADO CONTINUES TO SUSTAIN SHOWERS
OVER THE UINTA BASIN OF EASTERN UTAH AND FROM ABOUT RANGELY TO
VAIL PASS IN NORTHERN COLORADO. LITTLE PRECIPITATION IS EXPECTED
WITH THESE SHOWERS. ANTICIPATING A FEW SHOWERS DEVELOPING OVER
SOUTHEASTERN UTAH WITHIN THE NEXT FEW HOURS AHEAD OF THE DEEPER
PLUME OF MOISTURE WHICH WILL REACH THE FOUR CORNERS TONIGHT.

&&

.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 241 AM MDT MON AUG 18 2014

TODAY...STARTING OUT OVERNIGHT INTO THE EARLY MORNING WITH A FEW
SHOWERS AND THUNDERSTORMS MAINLY THE NORTHERN PORTION OF THE NW
SAN JUAN MOUNTAINS AND ALSO IN AREAS OF NW CO AND NE UT. THEN
DAYTIME HEATING WILL RESULT IN SCATTERED SHOWERS AND THUNDERSTORMS
THIS AFTERNOON MAINLY MOUNTAINS. WITH PWATS DOWN TO LESS THAN 0.75
INCH TODAY...ONLY EXPECT BRIEF MODERATE RAINFALL FROM STORMS...
THOUGH GUSTY OUTFLOW WINDS COULD BE IN EXCESS OF 45 MPH FROM SOME
STORMS. EXPECT MAX TEMPERATURES ABOUT THE SAME OR SLIGHTLY LOWER
THAN YESTERDAY.

THEN CONFIDENCE IS HIGH FOR THE NEXT MONSOONAL SURGE TONIGHT
THROUGH TUESDAY ESPECIALLY IN EASTERN UTAH AND FAR WESTERN
COLORADO. SEVERAL FACTORS SUPPORT THIS. FIRST AN UNSEASONABLY
VIGOROUS UPPER LOW WORKS DOWN THE CALIFORNIA COAST PUSHING THE
SUBTROPICAL HIGH CENTER OUT INTO TEXAS. 0-6KM SW FLOW ADVECTS DEEP
MOISTURE FROM THE BAJA REGION. SE UTAH PRECIP WATER VALUES CLIMB
OVER AN INCH THIS EVENING REACHING NEAR 1.2 INCHES BY NOON
TUESDAY. A SIGNIFICANT CHUNK OF JET-SUPPORTED ENERGY LIFTS THROUGH
EASTERN UTAH ON TUESDAY WITH THE BEST FORCING IN THE RIGHT
ENTRANCE QUAD OF THE 70KT JET OVER NE UTAH. THE BEST MIXTURE OF
FORCING AND DEEP MOISTURE LOOKS TO BE IN SE-EASTCENTRAL UTAH AND
FAR WESTERN COLORADO. INSTABILITY LOOKS LIMITED DUE TO LESS
SURFACE HEATING. STILL THE STRONGEST CELLS WILL PRODUCE SMALL
HAIL. STORM MOTION WILL BE TO THE NNE AT 20-25KTS SO OUTFLOW WIND
GUSTS OF 30-40 MPH SHOULD BE COMMON IN THE WESTERN CWA. THE
EASTERN CWA IS EXPECTED TO HAVE A LOWER THREAT OF HEAVY RAINS THAN
THE WESTERN PORTION.

.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 241 AM MDT MON AUG 18 2014

TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...
FORCING LIFTS NE OF THIS FORECAST AREA TUESDAY EVENING BUT DEEP
MOISTURE AND BOUNDARY INTERACTION SHOULD KEEP STORMS FIRING BEYOND
MIDNIGHT. WEDNESDAY THE WEST COAST TROUGH SETTLES NEAR SAN DIEGO.
SLIGHTLY DRIER AIR WORKS OVER UTAH. NO ORGANIZED DISTURBANCES SEEN
EJECTING OFF THE SOUTHERN CALIFORNIA LOW BUT MINOR WAVES WILL
LIKELY PROVIDE ADDITIONAL LIFT. STORM MOTION WILL BE TO THE ENE AT
20KTS AGAIN THREATENING GUSTY OUTFLOW WINDS. HEAVY RAIN POTENTIAL
DECREASES SOMEWHAT ON WEDNESDAY. THE MODELS END SHOWERS WEDNESDAY
EVENING. BUT PRECIP WATER VALUES REMAIN OVER 0.75 INCH OVER THE
SOUTHERN 2/3 OF THE CWA SO ISOLATED NOCTURNAL STORMS ARE
ANTICIPATED TO PERSIST THERE.

THURSDAY AND FRIDAY...
MODELS START OUT EARLY THURSDAY WITH CLOSED LOW CENTERED NEAR
SOUTHERN CA COAST...THEN THEY DIVERGE THEREAFTER. THE GFS MOVES
THE UPPER LOW INLAND THURSDAY AND INTO OUR CWA ON FRIDAY AS IT
COMES INTO PHASE WITH THE TROUGH TO THE NORTH. EC AND CANADIAN
MODELS WAIT TO MOVE THE UPPER LOW INLAND UNTIL FRIDAY AND SLOWLY
BRING IT UP TO THE FOUR CORNERS AREA BY SUNDAY. THE GFS SOLUTION
HAS ANOTHER SURGE OF MONSOONAL MOISTURE FOR OUR CWA ON THURSDAY
AND FRIDAY...WITH DRIER WESTERLY FLOW OVER THE WEEKEND. IN
CONTRAST...EC IS DRIER ON THURSDAY AND FRIDAY WITH THE MONSOONAL
MOISTURE FOR OUR CWA FRIDAY NIGHT INTO SUNDAY. NO SINGLE MODEL
SOLUTION PREFERRED AT THIS TIME...AND BELIEVE THE BROAD BRUSH
TREATMENT WITH SCATTERED SHOWERS AND THUNDERSTORMS IS THE BEST
FORECAST DURING THIS TIME PERIOD. MAX TEMPERATURES SHOULD
GENERALLY BE A LITTLE LOWER THAN NORMAL THROUGH THIS PERIOD DUE TO
CLOUDS AND SHOWERS...WHILE MIN TEMPERATURES LIKELY TO BE NEAR OR
A LITTLE ABOVE NORMAL DUE TO CLOUD COVER AND ELEVATED DEW POINT
TEMPERATURES.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1108 AM MDT MON AUG 18 2014

A LINE OF -SHRA SOUTH OF KCAG BUT NORTH OF THE BOOKCLIFFS
CONTINUES TO MOVE EAST THROUGH THE AREA THANKS TO A WEAK WEATHER
DISTURBANCE ACROSS NORTHERN COLORADO. ISOLATED -RA/-TSRA WILL
INCREASE IN COVERAGE OVER THE MOUNTAINS AROUND 18Z. KEGE AND KASE
HAVE A SLIGHT CHANCE OF RECEIVING A SHOWER OR THUNDERSTORM TODAY.
MOISTURE WILL INCREASE AFTER 12Z TUESDAY MORNING FROM THE
SOUTHWEST AND INCREASE THE COVERAGE OF RAIN SHOWERS AND
THUNDERSTORMS BY 18Z TUESDAY.

&&

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

$$

UPDATE...JAM
SHORT TERM...JRP/JOE
LONG TERM...JOE/JRP
AVIATION...JAM





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