FXUS65 KGJT 100412 AAA AFDGJT AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE GRAND JUNCTION CO 911 PM MST FRI JAN 9 2004 .UPDATED...FOG HAS RETURNED TO ALL THE ZONES THAT WERE SOCKED IN LAST NIGHT. ADVISORY EXPANDED TO INCLUDE THE UNCOMPAHGRE RIVER AND UINTA BASINS. PERSISTENCE TO PROBABLY WORK WELL ON SATURDAY WITH THE FOG LIFTING LATE MORNING...MELTING A BIT OF SNOW TO FEED THE LOW- LEVEL MOISTURE...WHICH WILL REFORM THE DENSE FOG BY LATE AFTERNOON. ALL THE WHILE THE MOUNTAIN FOLK ARE BASKING UNDER MOSTLY CLEAR SKIES AND MILD TEMPS. RAMEY && .DISCUSSION... SHORT TERM (TONIGHT THROUGH SATURDAY NIGHT)... OVERNIGHT LOW TEMPS APPEAR TO BE THE BIGGEST CHALLENGE IN THE SHORT- TERM. IN SOME LOCATIONS LAST NIGHT...FOG AND STATUS REMAINED THICK AND INSULATED THE NEAR SURFACE AIR PREVENTING SIGNIFICANT COOLING. IN OTHER AREAS THE FOG AND STATUS WAS JUST AS THICK BUT THE LOW TEMPS COOLED OFF DRAMATICALLY AGAIN. MODEL MOS GUIDANCE SEEMS TO HAVE NO REAL HANDLE ON IT. FOG APPEARS TO BE THINNING EARLY THIS AFTERNOON IN WEST-CNTRL CO VALLEYS AND IN THE UTAH GRAND FLAT. MORE THAN LIKELY THE SUN WILL MELT SOME OF THE SNOWCOVER AND EVAPORATE MOISTURE BACK INTO THE LOWER ATMOS...SO BELIEVE FOG WILL RETURN SHORTLY AFTER SUNSET AND PERSIST THROUGH SAT MORNING. WITH RIDGE AT THE SURFACE AND ALOFT...SAT WILL BE A REPEAT OF TODAY WITH GRADUAL LIFTING AND BURNING OFF OF THE FOG/STATUS DECK TRAPPED IN THE VALLEYS...FOLLOWED BY A RETURN OF THE FOG SAT NIGHT. WILL NOT REISSUE DENSE FOG ADVY UNTIL HAVE A BETTER IDEA OF THE FOG DENSITY WHEN IT BEGINS TO REFORM. THE MOUNTAINS OF EASTERN UTAH AND COLORADO AND MOST OTHER AREAS OUTSIDE OF CO ZONES 6/7/11 AND UT ZONES 24/27 WILL REMAIN MOSTLY CLEAR THROUGH THE PERIOD WITH A WARMING TREND. LONG TERM (SUNDAY THROUGH FRIDAY)...OVERALL MEDIUM RANGE MDLS IN GOOD AGREEMENT ALTHO GFS IS SHOWING A LITTLE MORE ENERGY WITH SHORTWAVE THAT MOVES THROUGH THE PACIFIC NORTHWEST MON-TUE. INCLINED TO SIDE WITH THE GFS AS NEWEST ETA FOLLOWS THIS TREND TOWARD THE END OF ITS CYCLE. SUNDAY AND MONDAY...A RIDGE OF HIGH PRESSURE WILL PERSIST THROUGH THIS PERIOD...AND ACTUALLY INTENSIFY SOME SUNDAY AFTERNOON. THIS WILL MAINTAIN STRONG VALLEY INVERSIONS WITHIN THE COLORADO AND GUNNISON RIVER VALLEYS PLUS THE UINTA BASIN. ABOVE THE INVERSIONS WARMER THAN NORMAL TEMPERATURES WILL PREVAIL. POPS DURING THIS PERIOD WILL BE NIL EXCEPT FOR SLIGHT CHANCE OVER THE UINTA MTNS DURING THE AFTERNOON AS NEXT UPSTREAM SYSTEM APPROACHES. TUESDAY...A FAIRLY ENERGETIC SHORT WAVE WILL DROP QUICKLY SOUTHWARD FROM MONTANA. MOISTURE WITH THIS SYSTEM WILL BE LIMITED BUT THE ASSOCIATED SFC FRONT MAY PROVIDE ENUF LIFT TO PRODUCE SCATTERED SHOWERS MAINLY OVER THE NRN MTNS. CAA MAY ALSO BE STRONG ENOUGH TO TEMPORARILY SCOUR FOGGY VALLEYS. NORTHWEST FLOW PERSISTS WEDNESDAY AND THURSDAY WITH EMBEDDED MINOR WAVES BRINGING A SLIGHT CHANCE OF SNOW TO THE NORTHERN MOUNTAINS. MOST AREAS WILL HAVE SOME COOLING...EXCEPT FOR WARMING IN THE GRAND VALLEY WITH EXPECTED MIXING. THE GFS INDICATES A STRONGER SHORT WAVE AND ASSOCIATED COLD FRONT ON FRIDAY. EXPECT FUTURE MODEL RUNS TO SHOW VARYING SOLUTIONS ON THE STRENGTH AND TIMING OF COLD FRONT...BUT THE TREND OF LOWER TEMPERATURES AND POSSIBLE SNOW ACCEPTED AS EASTERN CONUS LONG WAVE TROUGH MAY SHIFT WESTWARD. && .GJT WATCHES/WARNINGS/ADVISORIES... .CO...DENSE FOG ADVISORY FOR ZONES 6/11UNTIL 10 AM SATURDAY. .UT...DENSE FOG ADVISORY FOR ZONES 24/27 UNTIL 10 AM SATURDAY. && JOE/JDC/CJC/MC/PF