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000
FXUS65 KGJT 170904
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
304 AM MDT MON JUN 17 2013

.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 302 AM MDT MON JUN 17 2013

CONVECTION STILL CONTINUES...MUCH LIKE YESTERDAY...THOUGH LATEST
SATELLITE AND RADAR IMAGERY STRONGLY SUGGESTS IT WON/T LAST MUCH
LONGER. THE PUSH OF DRY AIR ANTICIPATED FOR TODAY DID NOT
MATERIALIZE FOR AREAS NORTH OF I-70 AS INDICATED BY 00Z GJT
SOUNDING OF .51 INCHES OF PWAT. HOWEVER...NAM12/GFS TIME SERIES OF
PWATS DOES SHOW A DECREASE THROUGH THE DAY WHICH MATCHES UP WITH
THE DRY AIR TRYING TO ENTER THE REST OF THE CWA. DIFFICULT TO
PINPOINT THE CULPRIT FOR THE CONTINUED CONVECTION THIS MORNING AS JET
REMAINS TO OUR SOUTH WITH LITTLE UPPER LEVEL DIVERGENCE OVERHEAD.
A STRONG VORT MAX IS MOVING OVER SRN WY WHILE A WEAK MAX IS MOVING
ACROSS SRN UT SO BELIEVE THIS LITTLE WAVE IS WORKING ON AVAILABLE
MOISTURE TO KEEP THE SHOWERS GOING. REGARDLESS...BY DAYBREAK ALL
PRECIP SHOULD BE OVER BEFORE ANOTHER ROUND OF CONVECTION KICKS OFF
DUE TO DAYTIME HEATING AND AVAILABLE MOISTURE THIS AFTERNOON.
BUMPED UP POPS SOMEWHAT SINCE NAM12...WHICH HAS BEEN DOING WELL
LATELY...CONTINUES TO FAVOR THE HIGHER TERRAIN ESPECIALLY THE SAN
JUANS.

THE BULK OF THE CONVECTION WILL DIMINISH THIS EVENING AFTER
SUNSET...BUT LIKE THE PREVIOUS FEW NIGHTS...A FEW ISOLATED SHOWERS
OR STORMS MAY PERSIST PAST MIDNIGHT.

A LARGE PACIFIC UPPER LOW WILL SLOWLY APPROACH THE PACIFIC NORTHWEST
COAST TUESDAY WHILE A WEAK 60KT UPPER JET IN THE SOUTHERN STREAM
CROSSES SOUTHERN CA TO THE 4 CORNERS. MODELS HAVE BEEN CONSISTENT
IN KEEPING THE PAC LOW OFFSHORE THROUGH TUESDAY. HOWEVER...A
RIDGE FROM SOUTHWESTERN CANADA DOWN TO NORTHERN MEXICO WILL
PREVENT THE GRADIENT FROM REALLY TIGHTENING OVER OUR AREA. WE
WILL LIKELY EXPERIENCE SOME GUSTINESS TUESDAY MAINLY FROM DAYTIME
MIXING ON A HOT SUMMER DAY BUT THINK THE STRONGER WINDS WILL HOLD
OFF UNTIL THE PAC LOW MAKES LANDFALL. THE EXCEPTION MAY BE
SOUTHEAST UT UNDERNEATH THE NOSE OF THAT ENCROACHING UPPER JET.

WEST TO SOUTHWEST FLOW ACROSS OUR AREA WILL CONTINUE THE DRYING
TREND TUESDAY. TIME-HEIGHT SECTIONS SHOW THE MID-LEVEL MOISTURE
LAYER SHRINKING AND ISENTROPIC ANALYSES HAVE THE BULK OF THE
MOISTURE SHIFTING EAST AS WELL. WILL CARRY ONLY ISOLATED AFTERNOON
THUNDERSTORMS OVER THE CO MTNS NEARER THE DIVIDE. AS THE THERMAL
RIDGE ALOFT MOVES OVERHEAD...WARMING ALOFT SHOULD BEGIN TO INHIBIT
DEEP CONVECTION. HIGH TEMPS WILL CONTINUE TO CREEP UPWARD.

.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 302 AM MDT MON JUN 17 2013

THE UPPER LOW MOVES INLAND OVER THE NORTHWEST STATES BY WEDNESDAY
MORNING. A SHORTWAVE ROTATING AROUND THE LOW LIFTS ACROSS ID DURING
THE DAY ON WEDNESDAY TIGHTENING THE GRADIENT WHILE AN ASSOCIATED
DRY COLD FRONT PUSHES ACROSS NRN UT. SOUTHWEST WINDS WILL STRENGTHEN
WEDNESDAY IN RESPONSE WITH DAYTIME MIXING BRINGING THE STRONGER
WINDS ALOFT DOWN TO THE SURFACE FOR GUSTY AFTERNOON WINDS AND
HEIGHTENED WILDFIRE CONCERNS. STRONGEST WINDS WILL BE FROM
SOUTHEAST UT UP ACROSS NORTHWEST CO. WEDNESDAY LOOKS DRY WITH
PRECIPITABLE WATER VALUES BELOW 1/4 INCH AND WARM AIR ALOFT
LIMITS DEEP CONVECTION.

FROM THURSDAY ONWARD...NO SENSIBLE WX IS EXPECTED OVER THE CWA
THOUGH WE WILL STILL BE AFFECTED BY THE AREA OF LOW PRESSURE TO
OUR NORTH. SWLY FLOW WILL CONTINUE WITH GUSTY AFTERNOON WINDS AS
GRADIENT REMAINS FAIRLY TIGHT THROUGH THE PERIOD. FIRE WEATHER
CONCERNS WILL CONTINUE UNDER THIS REGIME. TEMPERATURES WILL SEE
LITTLE VARIATION DAY TO DAY...RUNNING 2 TO 4 DEGREES ABOVE NORMAL.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 302 AM MDT MON JUN 17 2013

VISUAL FLIGHT RULES WILL CONTINUE FOR THE NEXT 24 HOURS. SOME
AFTERNOON CONVECTION IS EXPECTED THIS AFTERNOON WITH MOUNTAIN TAF
SITES...KEGE AND KASE...POSSIBLY SEEING SOME VCTS. SAN JUANS ARE
FAVORED AT THIS TIME AS IS THE DIVIDE THOUGH COVERAGE SHOULD BE
LESS THAN SEEN THE LAST FEW DAYS. REMAINING TAF SITES WILL SEE
MAINLY SCT SKIES AND GENERALLY LIGHT DIURNALLY DRIVEN WINDS.

&&

.FIRE WEATHER...
ISSUED AT 302 AM MDT MON JUN 17 2013

UPPER RIDGING WITH A GRADUALLY DRYING SOUTHWEST FLOW WILL PERSIST
INTO TUESDAY AFTERNOON OVER THE INTERMOUNTAIN WEST AND WESTERN
SLOPE. LOW PRESSURE MOVING INTO THE NORTHWEST STATES AND NORTHERN
ROCKIES BY MID WEEK WILL BEGIN TO BREAK DOWN THE RIDGE AND PUSH IT
EAST OF THE ROCKIES. THIS IN TURN WILL BRING IN STRONGER WINDS
ALOFT AS THE GRADIENT TIGHTENS BETWEEN THE DEPARTING RIDGE AND
APPROACHING UPPER LOW. ABOVE NORMAL TEMPERATURES AND NEAR ZERO
WETTING RAIN CHANCES WILL PERSIST EARLY THIS WEEK WHICH WILL
CONTINUE TO AFFECT FUEL MOISTURE. AREAS OF CRITICAL FIRE WEATHER
CONDITIONS MAY BEGIN TO INCREASE LATE TUESDAY IN THE FAR WESTERN
CWA AND COULD BECOME WIDESPREAD BY WEDNESDAY IN THIS FAVORABLE
PATTERN. THE DRY AND WINDY CONDITIONS MAY SURVIVE INTO THE LATE
WEEK PERIOD. FUEL SPECIALISTS AND FIRE MANAGERS ARE URGED TO KEEP
FUEL STATUS UPDATED.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...FIRE WEATHER WATCH FROM WEDNESDAY MORNING THROUGH WEDNESDAY
     EVENING FOR COZ200-202-203-207-290>293.

UT...FIRE WEATHER WATCH FROM WEDNESDAY MORNING THROUGH WEDNESDAY
     EVENING FOR UTZ483.

&&

$$

SHORT TERM...TGR/JAD
LONG TERM...TGR/JAD
AVIATION...TGR
FIRE WEATHER...TGR