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000
FXUS65 KGJT 140522
AFDGJT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1122 PM MDT MON MAY 13 2013

.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 402 PM MDT MON MAY 13 2013

WARM DAYTIME TEMPERATURES HAVE RESULTED IN ISOLATED TO SCATTERED
CONVECTION OVER THE HIGHER COLORADO MOUNTAINS THIS AFTERNOON. THIS
ACTIVITY WILL CONTINUE THIS EVENING...QUICKLY DIMINISHING WITH THE
SUNSET. OTHERWISE THE UPPER LEVEL FLOW WILL CONTINUE TO CARRY HIGH
CLOUDS IN A CLOCKWISE DIRECTION ACROSS THROUGHOUT THE NIGHT.

THESE RELATIVELY THIN HIGH CLOUDS WILL KEEP TEMPERATURES WARM
OVERNIGHT...ESPECIALLY AFTER THE WARM HIGH READINGS TODAY.

THEN THE RIDGE WILL FLATTEN LATE TONIGHT AND ON TUE AS SHORTWAVE
ENERGY RIDES ALONG THE U.S./CANADIAN BORDER. ALSO A COLD FRONT WILL
APPROACH FROM THE NORTH...BUT NOT REALLY MAKE IT INTO OUR AREA. IN
ADDITION A WEAK UPPER LOW THAT HAS BEEN SITTING OVER NORTHWEST
MEXICO WILL OPEN UP AND MOVE NORTHEAST ON TUE. WHILE OUR FORECAST
AREA WILL SIT BETWEEN THESE FEATURES...WE SHOULD SEE SOME SUBTLE
DIFFERENCES IN THE SENSIBLE WEATHER. FOR ONE...GRADIENT WINDS WILL
INCREASE A LITTLE OVER THE NORTH...WITH A WESTERLY FLOW DEVELOPING
AND A FEW AFTERNOON GUSTS. THE STRONGEST WINDS WILL BE ALONG THE
WYOMING BORDER. ALSO THE OPENING SOUTHERN LOW WILL BRUSH OUR
SOUTH...PROVIDING A BOOST TO OUR AFTERNOON CONVECTION. THIS
BOOST...COMBINED WITH PLENTY OF DAYTIME HEATING WILL ALLOW BETTER
CONVECTIVE COVERAGE. BUT STILL MOST ACTIVITY WILL BE CONFINED TO THE
MOUNTAINS.

THE RIDGE TEMPORARILY REBOUNDS AS ANOTHER RELATIVELY WEAK SHORTWAVE
MOVES INTO THE GREAT BASIN. CONVECTIVE ACTIVITY WILL AGAIN DIMINISH
WITH THE LOSS OF DAYTIME HEATING.

ABOVE NORMAL TEMPERATURES WILL PERSIST WITH TEMPERATURES 5-10
DEGREES OR BETTER ABOVE NORMAL.

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 402 PM MDT MON MAY 13 2013

WATER VAPOR IMAGERY SHOWS A WAVE MOVING INTO THE PACIFIC NORTHWEST
THIS AFTERNOON WITH A TRAILING WAVE JUST OFF THE NORTHERN CALIFORNIA
COAST. NOT MUCH IMPACT ON OUR AREA FROM THE NORTHERN STRING OF
ENERGY EXCEPT TO FLATTEN THE BROAD RIDGE OVER THE NORTHERN AND
CANADIAN ROCKIES BY WEDNESDAY MORNING. THE TRAILING
WAVE...UNHOOKED FROM THE FASTER WESTERLIES...WILL NOT ARRIVE INTO
THE GREAT BASIN UNTIL WEDNESDAY AFTERNOON. THIS WAVE WILL BE
WEAKENING ON IT WAY WEST. LIMITED ASCENT AND SUPPORT OVER OUR CWA
ASSOCIATED WITH THIS PIECE OF ENERGY SO EXPECT THE CONVECTION TO
REMAIN ON THE LIMITED TO SCATTERED SIDE AND MAINLY ANCHORED TO THE
TERRAIN. THIS WAVE WILL HOWEVER LEAD TO SOME BETTER MIXING AND
SOME AFTERNOON GUSTY WINDS CAN BE EXPECTED AS HUMIDITIES DROP.
ATTM CRITICAL FIRE WEATHER CONCERNS LOOK LIMITED AS GREEN UP IS
OCCURRING OVER MANY LOWER ELEVATIONS. HIGHS LOOK TO BE JUST A TAD
LOWER AS COOLER AIR WORKS IN ALOFT...BUT STILL REMAIN WELL ABOVE
NORMAL FOR MID MAY.

THE CONVECTION SHOULD WANE DURING THE LATE EVENING HOURS ON
WEDNESDAY AS THE FLOW BEGINS TO SLOWLY BACK TO THE SOUTHWEST THROUGH
THE DAY THURSDAY. THIS FLOW INITIALLY WILL BE DRAGGING IN DRIER AND
WARMER AIR WHICH WILL BE LIMITING THE CONVECTIVE POTENTIAL THURSDAY
AFTERNOON SO A DOWNTURN IN POPS LOOKS ON TRACK FROM PREVIOUS
FORECASTS. TEMPERATURES AND WINDS SHOULD RESPOND TO THE AIRMASS BY
WARMING AND BRINGING DOWN SOME STRONGER WIND GUSTS IN THE AFTERNOON.
AGAIN THE MAIN CONCERN WILL BE FOCUSED ON CRITICAL FIRE WEATHER
CONDITIONS. CONDITIONS REMAIN SIMILAR GOING INTO FRIDAY AS THE TROF
PUSHES INTO THE EASTERN GREAT BASIN. A TIGHTER GRADIENT ALOFT WILL
KEEP THINGS ON THE DRY AND WINDY CONDITIONS WITH SOUNDINGS SHOWING
ANY TRAPPED ABOVE 550MB SO VIRGA AND ISOLATED SHOWERS SEEM MORE
LIKELY THEN SIGNIFICANT PCPN ATTM.

A DEFINITE CHANGE TO THE PATTERN WILL COME BY THE WEEKEND AS THE
WESTERN TROF MOVES INTO THEN ACROSS OUR CWA. MOISTURE TRANSPORT
VECTORS SHOW SOME MOISTURE WRAPPING AHEAD OF THIS TROF BUT PWATS
LOOK TO REMAIN NEAR TO JUST SLIGHTLY ABOVE NORMAL. THE MODELS ARE
SHOWING THE ENERGY IN THE TROF SPLITTING FRIDAY AFTERNOON AND THEN
ARE SPLIT ON WHICH PORTION OF THE TROF WILL CARRY THE STRONGER PIECE
OF ENERGY. IT SEEMS EITHER WAY THE BEST LIFT WILL BE MOVING OUR CWA
FRIDAY NIGHT OUTSIDE OF THE TIME OF PEAK HEATING WHICH WILL LIMIT
SOME OF THE BETTER PRECIPITATION POTENTIAL. FOR NOW WILL KEEP POPS
ON THE LOWER SIDE AND RUN WITH THE BLENDED MODEL SOLUTIONS. MORE
CERTAIN IS THE COOLER AIR FILTERING IN BEHIND THIS TROF AND SURFACE
COLD FRONT WHICH WILL DROP HIGHS BACK INTO THE NORMAL TO BELOW
NORMAL READING OVER THE WEEKEND INTO EARLY NEXT WEEK. THE LATE
FORECAST MODEL SOLUTION REMAIN OUT OF PHASE WITH RESPECT TO SWINGING
ANOTHER BATCH OF NORTHERN STREAM ENERGY AROUND THE BACK OF THE TROF
ON SUNDAY WITH THE EURO THE MORE AGGRESSIVE SOLUTION. FOR NOW JUST
LOW END POPS ACROSS THE NORTHERN CWA WILL BE IN PLACE. ATTM MONDAY
LOOKS TO BE THE TRANSITION DAY BEFORE RIDGING AGAIN TAKES PLACE
ACROSS THE WEST AND BRING BACK WARMER TEMPERATURES TO THE CWA.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1120 PM MDT MON MAY 13 2013

VFR WILL PREVAIL ACROSS THE LOWER ELEVATIONS THROUGHOUT THE PERIOD
...AND ACROSS THE MOUNTAINS THROUGH TUE MORNING. ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS WILL REDEVELOP OVER THE
MOUNTAINS TUE AFTERNOON...WITH MOUNTAIN OBSCURATIONS AND GUSTY
OUTFLOW WINDS POSSIBLE. THE HIGHER COLORADO MOUNTAINS NEAR THE
DIVIDE...AND THE EASTERN UINTA MOUNTAINS WILL BE FAVORED.

&&

.FIRE WEATHER...(TONIGHT THROUGH MONDAY)
ISSUED AT 403 PM MDT MON MAY 13 2013

ABOVE NORMAL WARMTH AND MOSTLY DRY CONDITIONS ARE EXPECTED DURING
THE UPCOMING WEEK WHICH COULD QUICKLY RAISE FIRE WEATHER CONCERNS.
MUCH WILL BE DEPENDENT ON FUEL CONDITIONS...AND LAND AGENCIES ARE
ENCOURAGED TO KEEP THEIR FUELS STATUS UPDATED.

GUSTY SOUTHWEST WINDS SHOULD DEVELOP ON TUESDAY IN ADVANCE OF A DRY
BUT WEAK COLD FRONT. LOCALIZED CRITICAL WIND/LOW HUMIDITY CRITERIA
ARE POSSIBLE TUESDAY AFTERNOON MAINLY NORTH OF I-70 WHERE THE
STRONGER GUSTS ARE EXPECTED. CURRENT FUEL STATUS PRECLUDES ANY FIRE
WEATHER HIGHLIGHT AT THE MOMENT. THE FOCUS WILL THEN SHIFT TO
SOUTHWEST COLORADO ON WEDNESDAY BUT CRITICAL FIRE WEATHER
CONDITIONS WILL BE IN CHECK DUE TO GREEN UP CONDITIONS. STRONGER
AND MORE WIDESPREAD WIND WITH LOW HUMIDITY IS ANTICIPATED THURSDAY
AND FRIDAY AHEAD OF ANOTHER PACIFIC SYSTEM MOVING INLAND.

ISOLATED TO SCATTERED DIURNAL SHOWERS AND THUNDERSTORMS ARE EXPECTED
MAINLY OVER THE MTNS ON MOST DAYS THIS WEEK. STORMS WILL BE MAINLY
HIGH-BASED AND LIKELY TO PRODUCE MORE WIND THAN RAIN.

&&

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

$$

SHORT TERM...EH
LONG TERM...15
AVIATION...JDC
FIRE WEATHER...15