000
FXUS65 KGJT 251947
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
147 PM MDT SAT MAY 25 2013

.UPDATE...
ISSUED AT 147 PM MDT SAT MAY 25 2013

UPDATED TO UPGRADE FIRE WEATHER WATCH SUNDAY AFTERNOON AND EVENING
TO A RED FLAG WARNING. SEE UPDATED FIRE WEATHER SECTION BELOW AND
RFWGJT FOR DETAILS.

&&

.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 430 AM MDT SAT MAY 25 2013

CO AND UT WILL BE UNDER MODERATE SOUTHWEST FLOW ALOFT TODAY AS LOW
PRESSURE REMAINS STATIONARY OVER THE PACIFIC NW. CONDITIONS WILL
BE WARM AND DRY...WITH WINDS JUST STRONG FOR FIRE WEATHER
CONCERNS. OVER SOUTHWEST CO THE FUELS REMAIN DRY AND TODAY WINDS
AND LOW HUMIDITY WILL PRODUCE RED FLAG CONDITIONS AT LOWER
ELEVATIONS. TEMPERATURES WILL AVERAGE ABOUT 5 DEGREES ABOVE NORMAL
ACROSS THE FORECAST AREA. A WEAK VORT MAX PASSING OVER THE
CO/UT/WY TRIPLE POINT WILL PRODUCE SOME MID AND HI CLOUD THIS
MORNING BUT THESE WILL MOVE NORTH AND EAST OF THE AREA BY NOON.

TONIGHT AND SUNDAY...WINDS WILL DIMINISH THIS EVENING AFTER SUNSET
AS THE ATMOSPHERE DECOUPLES WITH THE LOSS OF HEATING.

ENERGY WILL CONTINUE TO ROTATE AROUND THE PAC NW LOW ON SUNDAY AND
MAINTAIN DRY SOUTHWEST FLOW ACROSS THE FORECAST AREA. MODELS SHOW AN
UPSTREAM PACIFIC DISTURBANCE DIGGING FARTHER SOUTH INTO NORTHWEST NV
BY SUNDAY AFTERNOON...WHILE A SHORTWAVE TROUGH IN THE SOUTHERN
STREAM ENTERS SRN CA. HIGH CLOUDS WILL INCREASE SUNDAY AFTERNOON
AS THE NOSE OF A WEAK UPPER JET MOVES IN FROM THE SOUTHWEST. DAYTIME
HEATING WILL AGAIN PROVIDE A GUSTY CHARACTERISTIC TO THE AFTERNOON
WINDS. WARMER THAN NORMAL TEMPERATURES CONTINUE.

.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 430 AM MDT SAT MAY 25 2013

SUNDAY NIGHT AND MONDAY...THE SRN CA DISTURBANCE WILL MOVE
ACROSS THE 4 CORNERS TOWARD MIDDAY ON MONDAY. THE SHORTWAVE
DISTURBANCE THAT MOVES INTO NV LATE SUNDAY WILL LIFT ACROSS SRN
ID/WRN WY ON MONDAY AS IT ROTATES AROUND THE UPPER LOW STILL
LOCATED OVER THE PACIFIC NW. THESE SHOULD BRING A BIT MORE CLOUDS
TO THE AREA ON MONDAY AND IN TURN A FEW DEGREES OF COOLING...BUT
NO PRECIPITATION.

MONDAY THROUGH FRIDAY...THE TROUGH ALONG THE WEST COAST WILL BEGIN
MOVING INLAND MONDAY. THE UPPER WINDS OVER THE FORECAST AREA WILL
BECOME MORE SOUTHERLY MONDAY AND MONDAY NIGHT. BY SUNRISE TUE THE
NEGATIVE TILT TROF WILL BE OVER THE GREAT BASIN WITH INCREASING
MID AND HI CLOUD SPREADING OVER EASTERN UT AND WESTERN CO. THE
REMAINS OF A WEAK SURFACE FRONT IS PROJECTED TO MOVE THROUGH THE
FORECAST AREA LATE TUE AFTERNOON AND TUE EVENING. WITH THE
INCREASING HIGH MOISTURE AND GREATER INSTABILITY...DRY
THUNDERSTORMS WILL BE A POSSIBILITY TUE AFTERNOON AND EVENING.

THE SURFACE FRONT SHOULD BE EAST OF THE FORECAST AREA BY WED
MORNING WITH NORTHWEST FLOW AND A BETTER CHANCE OF PRECIPITATION
TUE NIGHT AND WED. WESTERN FLOW WILL DEVELOP OVER THE AREA WED
AFTERNOON AND THURSDAY AS THE POLAR JET RIDES JUST SOUTH OF THE
FOUR CORNERS. DRIER AIR WITH NW FLOW WILL SPREAD ACROSS THE AREA
THU NIGHT AND FRIDAY.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1041 AM MDT SAT MAY 25 2013

VFR CONDITIONS WILL CONTINUE ACROSS THE REGION FOR THE NEXT 24
HOURS. BREEZY SOUTHWEST WINDS RANGING FROM 15 TO 25 MPH ON AVERAGE
WILL RESULT IN AREAS MODERATE MECHANICAL TURBULENCE THROUGH 03Z
SUNDAY.


&&

.FIRE WEATHER...
ISSUED AT 147 PM MDT SAT MAY 25 2013

RED FLAG CONDITIONS WILL CONTINUE THIS AFTERNOON AND EVENING
ACROSS CO ZONES 207 AND 291 WHERE FUELS ARE CRITICAL...AS DRY AND
WARM SOUTHWEST FLOW PERSISTS OVER EASTERN UTAH AND WESTERN
COLORADO. THE CRITICAL FIRE WEATHER CONDITIONS WILL EASE AFTER
SUNSET TONIGHT AS WINDS DIMINISH.

UPGRADED FIRE WEATHER WATCH TO RED FLAG WARNING FOR THESE SAME
ZONES...207 AND 291...FOR SUNDAY AFTERNOON/EVENING FOR LOW
HUMIDITY...GUSTY WINDS...AND A HAINES INDEX OF 6. LATEST GUIDANCE
INDICATED A DECREASE IN HIGH CLOUDS DURING THE AFTERNOON WHICH...
IN CONJUNCTION WITH WEAK SHORTWAVE TROUGH...WILL ALLOW FOR WHAT
APPEARS TO BE SUFFICIENTLY DEEP MIXING TO GENERATE WIDESPREAD
WIND GUSTS OVER 25 MPH. AIRMASS WILL REMAIN WARM AND DRY SO RH
BELOW 15 PERCENT ALMOST CERTAIN.

AS THE LARGER-SCALE WESTERN TROUGH BEGINS TO MOVE INLAND NEXT
WEEK....AN INCREASE IN THE WINDS AND HIGH/MID LEVEL MOISTURE MAY
LEAD TO MORE FIRE WEATHER ISSUES INCLUDING DRY THUNDERSTORM ACTIVITY
ABOUT TUESDAY. COOLER CONDITIONS ARE EXPECTED AFTER WEDNESDAY.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR COZ207-291.
     RED FLAG WARNING FROM NOON TO 9 PM MDT SUNDAY FOR COZ207-291.

UT...NONE.

&&

$$

UPDATE...NL
SHORT TERM...CC/JAD
LONG TERM...CC/JAD
AVIATION...NL
FIRE WEATHER...CC/JAD/NL